tty: sysrq: switch sysrq handlers from int to u8

The passed parameter to sysrq handlers is a key (a character). So change
the type from 'int' to 'u8'. Let it specifically be 'u8' for two
reasons:
* unsigned: unsigned values come from the upper layers (devices) and the
tty layer assumes unsigned on most places, and
* 8-bit: as that what's supposed to be one day in all the layers built
on the top of tty. (Currently, we use mostly 'unsigned char' and
somewhere still only 'char'. (But that also translates to the former
thanks to -funsigned-char.))

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Zqiang <qiang.zhang1211@gmail.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de> # DRM
Acked-by: WANG Xuerui <git@xen0n.name> # loongarch
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20230712081811.29004-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/i915: Implement dedicated fbdev I/O helpers

Implement dedicated fbdev helpers for framebuffer I/O instead
of using DRM's helpers. Use an fbdev generator macro for
deferred I/O to create the fbdev callbacks. i915 was the only
caller of the DRM helpers, so remove them from the helper module.

i915's fbdev emulation is still incomplete as it doesn't implement
deferred I/O and damage handling for mmaped pages.

v4:
* generate deferred-I/O helpers
* use initializer macros for fb_ops
v2:
* use FB_IO_HELPERS options

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230530151228.22979-14-tzimmermann@suse.de

drm/fbdev-generic: Implement dedicated fbdev I/O helpers

Implement dedicated fbdev helpers for framebuffer I/O instead
of using DRM's helpers. Use an fbdev generator macro for
deferred I/O to create the callbacks. Fbdev-generic was the
only caller of the DRM helpers, so remove them from the helper
module.

v4:
* generate deferred-I/O helpers
* use initializer macros for fb_ops
v2:
* use FB_SYS_HELPERS_DEFERRED option

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Sui Jingfeng <suijingfeng@loongson.cn>
Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20230530151228.22979-13-tzimmermann@suse.de

drm/fb-helper: Export helpers for marking damage areas

Export drm_fb_helper_damage() and drm_fb_helper_damage_range(), which
handle damage areas for fbdev emulation. This is a temporary export
that allows to move the DRM I/O helpers for fbdev into drivers. Only
fbdev-generic and i915 need them. Both will be updated to implement
damage handling by themselves and the exported functions will be removed.

v4:
* update interfaces

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230530151228.22979-11-tzimmermann@suse.de

drm/fb-helper: Fix height, width, and accel_flags in fb_var

Fbtest contains some very simple validation of the fbdev userspace API
contract. When used with shmob-drm, it reports the following warnings
and errors:

height changed from 68 to 0
height was rounded down
width changed from 111 to 0
width was rounded down
accel_flags changed from 0 to 1

The first part happens because __fill_var() resets the physical
dimensions of the first connector, as filled in by drm_setup_crtcs_fb().
Fix this by retaining the original values.

The last part happens because __fill_var() forces the FB_ACCELF_TEXT
flag on, while fbtest disables all acceleration on purpose, so it can
draw safely to the frame buffer. Fix this by setting accel_flags to
zero, as DRM does not implement any text console acceleration.
Note that this issue can also be seen in the output of fbset, which
reports "accel true".

Fixes: ee4cce0a8f03a333 ("drm/fb-helper: fix input validation gaps in check_var")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/57e6b334dae8148b1b8ae6ef308ce9a83810a850.1684854344.git.geert+renesas@glider.be

drm/fb-helper: Use fb_{cfb,sys}_{read, write}()

Implement DRM fbdev helpers for reading and writing framebuffer
memory with the respective fbdev functions. Removes duplicate
code.

v2:
* rename fb_cfb_() to fb_io_() (Geert)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Sui Jingfeng <suijingfeng@loongson.cn>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230428122452.4856-20-tzimmermann@suse.de

drm/fbdev-generic: prohibit potential out-of-bounds access

The fbdev test of IGT may write after EOF, which lead to out-of-bound
access for drm drivers with fbdev-generic. For example, run fbdev test
on a x86+ast2400 platform, with 1680x1050 resolution, will cause the
linux kernel hang with the following call trace:

Oops: 0000 [#1] PREEMPT SMP PTI
[IGT] fbdev: starting subtest eof
Workqueue: events drm_fb_helper_damage_work [drm_kms_helper]
[IGT] fbdev: starting subtest nullptr

RIP: 0010:memcpy_erms+0xa/0x20
RSP: 0018:ffffa17d40167d98 EFLAGS: 00010246
RAX: ffffa17d4eb7fa80 RBX: ffffa17d40e0aa80 RCX: 00000000000014c0
RDX: 0000000000001a40 RSI: ffffa17d40e0b000 RDI: ffffa17d4eb80000
RBP: ffffa17d40167e20 R08: 0000000000000000 R09: ffff89522ecff8c0
R10: ffffa17d4e4c5000 R11: 0000000000000000 R12: ffffa17d4eb7fa80
R13: 0000000000001a40 R14: 000000000000041a R15: ffffa17d40167e30
FS: 0000000000000000(0000) GS:ffff895257380000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffa17d40e0b000 CR3: 00000001eaeca006 CR4: 00000000001706e0
Call Trace:
<TASK>
? drm_fbdev_generic_helper_fb_dirty+0x207/0x330 [drm_kms_helper]
drm_fb_helper_damage_work+0x8f/0x170 [drm_kms_helper]
process_one_work+0x21f/0x430
worker_thread+0x4e/0x3c0
? __pfx_worker_thread+0x10/0x10
kthread+0xf4/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
CR2: ffffa17d40e0b000
---[ end trace 0000000000000000 ]---

The is because damage rectangles computed by
drm_fb_helper_memory_range_to_clip() function is not guaranteed to be
bound in the screen's active display area. Possible reasons are:

1) Buffers are allocated in the granularity of page size, for mmap system
call support. The shadow screen buffer consumed by fbdev emulation may
also choosed be page size aligned.

2) The DIV_ROUND_UP() used in drm_fb_helper_memory_range_to_clip()
will introduce off-by-one error.

For example, on a 16KB page size system, in order to store a 1920x1080
XRGB framebuffer, we need allocate 507 pages. Unfortunately, the size
1920*1080*4 can not be divided exactly by 16KB.

1920 * 1080 * 4 = 8294400 bytes
506 * 16 * 1024 = 8290304 bytes
507 * 16 * 1024 = 8306688 bytes

line_length = 1920*4 = 7680 bytes

507 * 16 * 1024 / 7680 = 1081.6

off / line_length = 507 * 16 * 1024 / 7680 = 1081
DIV_ROUND_UP(507 * 16 * 1024, 7680) will yeild 1082

memcpy_toio() typically issue the copy line by line, when copy the last
line, out-of-bound access will be happen. Because:

1082 * line_length = 1082 * 7680 = 8309760, and 8309760 > 8306688

Note that userspace may still write to the invisiable area if a larger
buffer than width x stride is exposed. But it is not a big issue as
long as there still have memory resolve the access if not drafting so
far.

- Also limit the y1 (Daniel)
- keep fix patch it to minimal (Daniel)
- screen_size is page size aligned because of it need mmap (Thomas)
- Adding fixes tag (Thomas)

Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
Fixes: aa15c677cc34 ("drm/fb-helper: Fix vertical damage clipping")
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/dri-devel/ad44df29-3241-0d9e-e708-b0338bf3c623@189.cn/
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230420030500.1578756-1-suijingfeng@loongson.cn

drm/fb-helper: fix input validation gaps in check_var

Apparently drivers need to check all this stuff themselves, which for
most things makes sense I guess. And for everything else we luck out,
because modern distros stopped supporting any other fbdev drivers than
drm ones and I really don't want to argue anymore about who needs to
check stuff. Therefore fixing all this just for drm fbdev emulation is
good enough.

Note that var->active is not set or validated. This is just control
flow for fbmem.c and needs to be validated in there as needed.

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404194038.472803-3-daniel.vetter@ffwll.ch

drm/fb-helper: drop redundant pixclock check from drm_fb_helper_set_par()

The fb_check_var hook is supposed to validate all this stuff. Any
errors from fb_set_par are considered driver/hw issues and resulting
in dmesg warnings.

Luckily we do fix up the pixclock already, so this is all fine.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404194038.472803-2-daniel.vetter@ffwll.ch

drm/fb-helper: set x/yres_virtual in drm_fb_helper_check_var

Drivers are supposed to fix this up if needed if they don't outright
reject it. Uncovered by 6c11df58fd1a ("fbmem: Check virtual screen
sizes in fb_set_var()").

Reported-by: syzbot+20dcf81733d43ddff661@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=c5faf983bfa4a607de530cd3bb008888bf06cefc
Cc: stable@vger.kernel.org # v5.4+
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404194038.472803-1-daniel.vetter@ffwll.ch

drm/fb-helper: Consolidate CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM

Consolidate all handling of CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM by
making the module parameter optional in drm_fb_helper.c.

Without the config option, modules can set smem_start in struct
fb_info for internal usage, but not export if to userspace. The
address can only be exported by enabling the option and setting
the module parameter. Also update the comment.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Zack Rusin <zackr@vmware.com>
Tested-by: Sui Jingfeng<suijingfeng@loongson.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20230320150751.20399-8-tzimmermann@suse.de

drm/fb-helper: Support smem_len in deferred I/O

The size of the framebuffer can either be stored in screen_info or
smem_len. Take both into account in the deferred I/O code.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Sui Jingfeng <suijingfeng@loongson.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20230320150751.20399-5-tzimmermann@suse.de

drm/fb-helper: Export drm_fb_helper_release_info()

Export the fb_info release code as drm_fb_helper_release_info(). Will
help with cleaning up failed fbdev probing.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Zack Rusin <zackr@vmware.com>
Tested-by: Sui Jingfeng<suijingfeng@loongson.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20230320150751.20399-4-tzimmermann@suse.de

drm/fb-helper: Remove drm_fb_helper_unprepare() from drm_fb_helper_fini()

Move drm_fb_helper_unprepare() from drm_fb_helper_fini() into the
calling fbdev implementation. Avoids a possible stale mutex with
generic fbdev code.

As indicated by its name, drm_fb_helper_prepare() prepares struct
drm_fb_helper before setting up the fbdev support with a call to
drm_fb_helper_init(). In legacy fbdev emulation, this happens next
to each other. If successful, drm_fb_helper_fini() later tear down
the fbdev device and also unprepare via drm_fb_helper_unprepare().

Generic fbdev emulation prepares struct drm_fb_helper immediately
after allocating the instance. It only calls drm_fb_helper_init()
as part of processing a hotplug event. If the hotplug-handling fails,
it runs drm_fb_helper_fini(). This unprepares the fb-helper instance
and the next hotplug event runs on stale data.

Solve this by moving drm_fb_helper_unprepare() from drm_fb_helper_fini()
into the fbdev implementations. Call it right before freeing the
fb-helper instance.

Fixes: 643231b28380 ("drm/fbdev-generic: Minimize hotplug error handling")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230216140620.17699-1-tzimmermann@suse.de

drm/fb-helper: Initialize fb-helper's preferred BPP in prepare function

Initialize the fb-helper's preferred_bpp field early from within
drm_fb_helper_prepare(); instead of the later client hot-plugging
callback. This simplifies the generic fbdev setup function.

No real changes, but all drivers' fbdev code has to be adapted.

v3:
* build with CONFIG_DRM_FBDEV_EMULATION unset (kernel test bot)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-7-tzimmermann@suse.de

drm/fb-helper: Remove preferred_bpp parameter from fbdev internals

Store the console's preferred BPP value in struct drm_fb_helper
and remove the respective function parameters from the internal
fbdev code.

The BPP value is only required as a fallback and will now always
be available in the fb-helper instance.

No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-6-tzimmermann@suse.de

drm/fb-helper: Introduce drm_fb_helper_unprepare()

Move the fb-helper clean-up code into drm_fb_helper_unprepare(). No
functional changes.

v2:
* declare as static inline (kernel test robot)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-4-tzimmermann@suse.de

drm/fb-helper: Do not allocate unused apertures structure

The apertures field in struct fb_info is not used by DRM drivers. Do
not allocate it.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219160516.23436-7-tzimmermann@suse.de

drm/fb-helper: Replace bpp/depth parameter by color mode

Replace the combination of bpp and depth with a single color-mode
argument. Handle special cases in simpledrm and ofdrm. Hard-code
XRGB8888 as fallback format for cases where no given format works.

The color-mode argument accepts the same values as the kernel's video
parameter. These are mostly bpp values between 1 and 32. The exceptions
are 15, which has a color depth of 15 and a bpp value of 16; and 32,
which has a color depth of 24 and a bpp value of 32.

v4:
* add back lost test for bpp_specified (Maira)
* add Fixes tag (Daniel)
v3:
* fix ofdrm build (Maxime)
v2:
* minimize changes (Daniel)
* use drm_driver_legacy_fb_format() (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Maíra Canal <mcanal@igalia.com> # vc4 and vkms
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Fixes: 37c90d589dc0 ("drm/fb-helper: Fix single-probe color-format selection")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230106112324.22055-1-tzimmermann@suse.de

drm/fb-helper: Fix single-probe color-format selection

Fix the color-format selection of the single-probe helper. Go
through all user-specified values and test each for compatibility
with the driver. If none is supported, use the driver-provided
default. This guarantees that the console is always available in
any color format at least.

Until now, the format selection of the single-probe helper tried
to either use a user-specified format or a 32-bit default format.
If the user-specified format was not supported by the driver, the
selection failed and the display remained blank.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230102112927.26565-12-tzimmermann@suse.de

drm/fh-helper: Split fbdev single-probe helper

Split the single-probe helper's implementation into multiple
functions and get locking and overallocation out of the way of
the surface setup. Simplifies later changes to the setup code.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230102112927.26565-11-tzimmermann@suse.de

Revert "drm/fb-helper: Perform damage handling in deferred-I/O helper"

This reverts commit 5fc586a058babc71c82a038477581b7bfe1c6e2a.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-4-tzimmermann@suse.de

Revert "drm/fb-helper: Schedule deferred-I/O worker after writing to framebuffer"

This reverts commit 7f5cc4a3e5e4c5a38e5748defc952e45278f7a70.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-3-tzimmermann@suse.de

Revert "drm/fb-helper: Remove damage worker"

This reverts commit 27c3e9452d552ea86369a94f23287a9675f2d7a1.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-2-tzimmermann@suse.de

drm/fb-helper: Set framebuffer for vga-switcheroo clients

Set the framebuffer info for drivers that support VGA switcheroo. Only
affects the amdgpu and nouveau drivers, which use VGA switcheroo and
generic fbdev emulation. For other drivers, this does nothing.

This fixes a potential regression in the console code. Both, amdgpu and
nouveau, invoked vga_switcheroo_client_fb_set() from their internal fbdev
code. But the call got lost when the drivers switched to the generic
emulation.

Fixes: 087451f372bf ("drm/amdgpu: use generic fb helpers instead of setting up AMD own's.")
Fixes: 4a16dd9d18a0 ("drm/nouveau/kms: switch to drm fbdev helpers")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Evan Quan <evan.quan@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Hawking Zhang <Hawking.Zhang@amd.com>
Cc: Likun Gao <Likun.Gao@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Stanley Yang <Stanley.Yang@amd.com>
Cc: "Tianci.Yin" <tianci.yin@amd.com>
Cc: Xiaojian Du <Xiaojian.Du@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: YiPeng Chai <YiPeng.Chai@amd.com>
Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
Cc: Bokun Zhang <Bokun.Zhang@amd.com>
Cc: Guchun Chen <guchun.chen@amd.com>
Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Solomon Chiu <solomon.chiu@amd.com>
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Marek Olšák" <marek.olsak@amd.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.17+
Link: https://patchwork.freedesktop.org/patch/msgid/20230116115425.13484-3-tzimmermann@suse.de

Revert "drm/fb-helper: Perform damage handling in deferred-I/O helper"

This reverts commit 5fc586a058babc71c82a038477581b7bfe1c6e2a.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-4-tzimmermann@suse.de
(cherry picked from commit e3ddd2d25533d1cc6f9fea421e4a5f16b60b3434)

Revert "drm/fb-helper: Schedule deferred-I/O worker after writing to framebuffer"

This reverts commit 7f5cc4a3e5e4c5a38e5748defc952e45278f7a70.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-3-tzimmermann@suse.de
(cherry picked from commit 8b83e1a455382dc667898a525a93f4eb6716cc41)

Revert "drm/fb-helper: Remove damage worker"

This reverts commit 27c3e9452d552ea86369a94f23287a9675f2d7a1.

Needed to restore the fbdev damage worker. There have been bug reports
about locking order [1] and incorrectly takens branches. [2] Restore
the damage worker until these problems have been resovled.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://intel-gfx-ci.01.org/tree/drm-tip/fi-kbl-8809g.html # 1
Link: https://lore.kernel.org/dri-devel/20221115115819.23088-6-tzimmermann@suse.de/T/#m06eedc0a468940e4cbbd14ca026733b639bc445a # 2
Link: https://patchwork.freedesktop.org/patch/msgid/20221118133535.9739-2-tzimmermann@suse.de
(cherry picked from commit 7aa3d63e1ad56c174536a5aba76d8a54c4c5acb4)

drm/fb-helper: Remove damage worker

The fbdev damage worker is unused, so remove it.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-7-tzimmermann@suse.de

drm/fb-helper: Schedule deferred-I/O worker after writing to framebuffer

Schedule the deferred-I/O worker instead of the damage worker after
writing to the fbdev framebuffer. The deferred-I/O worker then performs
the dirty-fb update. The fbdev emulation will initialize deferred I/O
for all drivers that require damage updates. It is therefore a valid
assumption that the deferred-I/O worker is present.

It would be possible to perform the damage handling directly from within
the write operation. But doing this could increase the overhead of the
write or interfere with a concurrently scheduled deferred-I/O worker.
Instead, scheduling the deferred-I/O worker with its regular delay of
50 ms removes load off the write operation and allows the deferred-I/O
worker to handle multiple write operations that arrived during the delay
time window.

v3:
* remove unused variable (lkp)
v2:
* keep drm_fb_helper_damage() (Daniel)
* use fb_deferred_io_schedule_flush() (Daniel)
* clarify comments (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-6-tzimmermann@suse.de

drm/fb-helper: Perform damage handling in deferred-I/O helper

Call fb_dirty directly from drm_fb_helper_deferred_io() to avoid the
latency of running the damage worker.

The deferred-I/O helper drm_fb_helper_deferred_io() runs in a worker
thread at regular intervals as part of writing to mmaped framebuffer
memory. It used to schedule the fbdev damage worker to flush the
framebuffer. Changing this to flushing the framebuffer directly avoids
the latency introduced by the damage worker.

v2:
* remove fb_dirty from defio in separate patch (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-5-tzimmermann@suse.de

drm/fb-helper: Remove test for fb_dirty callback from deferred-I/O helper

The helper for processing deferred I/O on pages has no dependency on
the fb_dirty damge-handling callback; so remove the test. In practice,
deferred I/O is only used with damage handling and the damage worker
already guarantees the presence of the fb_dirty callback.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-4-tzimmermann@suse.de

drm/fb-helper: Move dirty-fb update into helper function

Move the dirty-fb update from the damage-worker callback into the
new helper drm_fb_helper_fb_dirty(), so that it can run outside the
damage worker. This change will help to remove the damage worker
entirely. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-3-tzimmermann@suse.de

drm/fb-helper: Set damage-clip area in helper

Set the damage area in the new helper drm_fb_helper_add_damage_clip().
It can now be updated without scheduling the damage worker. This change
will help to remove the damage worker entirely. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221115115819.23088-2-tzimmermann@suse.de

drm/fb-helper: Clarify use of last_close and output_poll_changed

Clarify documentation in the use of struct drm_driver.last_close and
struct drm_mode_config_funcs.output_poll_changed. Those callbacks should
not be said for fbdev implementations on top of struct drm_client_funcs.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-24-tzimmermann@suse.de

drm/fb-helper: Move generic fbdev emulation into separate source file

Move the generic fbdev implementation into its own source and header
file. Adapt drivers. No functional changes, but some of the internal
helpers have been renamed to fit into the drm_fbdev_ naming scheme.

v3:
* rename drm_fbdev.{c,h} to drm_fbdev_generic.{c,h}
* rebase onto vmwgfx changes
* rebase onto xlnx changes
* fix include statements in amdgpu

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-22-tzimmermann@suse.de

drm/fb-helper: Set flag in struct drm_fb_helper for leaking physical addresses

Uncouple the parameter drm_leak_fbdev_smem from the implementation by
setting a flag in struct drm_fb_helper. This will help to move the
generic fbdev emulation into its own source file, while keeping the
parameter in drm_fb_helper.c. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-21-tzimmermann@suse.de

drm/fb-helper: Always initialize generic fbdev emulation

Initialize the generic fbdev emulation even if it has been disabled
on the kernel command line. The hotplug and mode initialization will
fail accordingly.

The kernel parameter can still be changed at runtime and the emulation
will initialize after hotplugging the connector.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-20-tzimmermann@suse.de

drm/fb_helper: Minimize damage-helper overhead

Pull the test for fb_dirty into the caller to avoid extra work
if no callback has been set. In this case no damage handling is
required and no damage area needs to be computed. Print a warning
if the damage worker runs without getting an fb_dirty callback.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-19-tzimmermann@suse.de

drm/fb-helper: Perform all fbdev I/O with the same implementation

Implement the fbdev's read/write helpers with the same functions. Use
the generic fbdev's code as template. Convert all drivers.

DRM's fb helpers must implement regular I/O functionality in struct
fb_ops and possibly perform a damage update. Handle all this in the
same functions and convert drivers. The functionality has been used
as part of the generic fbdev code for some time. The drivers don't
set struct drm_fb_helper.fb_dirty, so they will not be affected by
damage handling.

For I/O memory, fb helpers now provide drm_fb_helper_cfb_read() and
drm_fb_helper_cfb_write(). Several drivers require these. Until now
tegra used I/O read and write, although the memory buffer appears to
be in system memory. So use _sys_ helpers now.

v3:
* fix docs (Javier)
v2:
* rebase onto vmwgfx changes

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-18-tzimmermann@suse.de

drm/fb-helper: Call fb_sync in I/O functions

Call struct fb_ops.fb_sync in drm_fbdev_{read,write}() to mimic the
behavior of fbdev. Fbdev implementations of fb_read and fb_write in
struct fb_ops invoke fb_sync to synchronize with outstanding operations
before I/O. Doing the same in DRM implementations will allow us to use
them throughout DRM drivers.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-17-tzimmermann@suse.de

drm/fb-helper: Disconnect damage worker from update logic

The fbdev helpers implement a damage worker that forwards fbdev
updates to the DRM driver. The worker's update logic depends on
the generic fbdev emulation. Separate the two via function pointer.

The generic fbdev emulation sets struct drm_fb_helper_funcs.fb_dirty,
a new callback that hides the update logic from the damage worker.
It's not possible to use the generic logic with other fbdev emulation,
because it contains additional code for the shadow buffering that
the generic emulation employs.

DRM drivers with internal fbdev emulation can set fb_dirty to their
own implementation if they require damage handling; although no such
drivers currently exist.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-16-tzimmermann@suse.de

drm/fb-helper: Rename drm_fb_helper_unregister_fbi() to use _info postfix

Rename drm_fb_helper_unregister_fbi() to drm_fb_helper_unregister_info()
as part of unifying the naming within fbdev helpers. Adapt drivers. No
functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-15-tzimmermann@suse.de

drm/fb-helper: Rename drm_fb_helper_alloc_fbi() to use _info postfix

Rename drm_fb_helper_alloc_fbi() to drm_fb_helper_alloc_info() as
part of unifying the naming within fbdev helpers. Adapt drivers. No
functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-14-tzimmermann@suse.de

drm/fb_helper: Rename field fbdev to info in struct drm_fb_helper

Rename struct drm_fb_helper.fbdev to info. The current name is
misleading as it overlaps with generic fbdev naming conventions.
Adapt to the usual naming in fbdev drivers by calling the field
'info'. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-13-tzimmermann@suse.de

drm/fb-helper: Add support for DRM_FORMAT_C[124]

Add support for color-indexed frame buffer formats with two, four, and
sixteen colors to the DRM framebuffer helper functions:
1. Add support for 1, 2, and 4 bits per pixel to the damage helper,
2. For color-indexed modes, the length of the color bitfields must be
set to the color depth, else the logo code may pick a logo with too
many colors. Drop the incorrect DAC width comment, which
originates from the i915 driver.
3. Accept C[124] modes when validating or filling in struct
fb_var_screeninfo, and use the correct number of bits per pixel.
4. Set the visual to FB_VISUAL_PSEUDOCOLOR for all color-indexed
modes.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/db3e80b445df661ff0cd7e698507a8d24a4c867e.1657294931.git.geert@linux-m68k.org

drm/fb-helper: Fix out-of-bounds access

Clip memory range to screen-buffer size to avoid out-of-bounds access
in fbdev deferred I/O's damage handling.

Fbdev's deferred I/O can only track pages. From the range of pages, the
damage handler computes the clipping rectangle for the display update.
If the fbdev screen buffer ends near the beginning of a page, that page
could contain more scanlines. The damage handler would then track these
non-existing scanlines as dirty and provoke an out-of-bounds access
during the screen update. Hence, clip the maximum memory range to the
size of the screen buffer.

While at it, rename the variables min/max to min_off/max_off in
drm_fb_helper_deferred_io(). This avoids confusion with the macros of
the same name.

Reported-by: Nuno Gonçalves <nunojpg@gmail.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Nuno Gonçalves <nunojpg@gmail.com>
Fixes: 67b723f5b742 ("drm/fb-helper: Calculate damaged area in separate helper")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: <stable@vger.kernel.org> # v5.18+
Link: https://patchwork.freedesktop.org/patch/msgid/20220621104617.8817-1-tzimmermann@suse.de

drm: Drop drm_framebuffer.h from drm_crtc.h

drm_crtc.h has no need for drm_frambuffer.h, so don't include it.
Avoids useless rebuilds of the entire universe when
touching drm_framebuffer.h.

Quite a few placs do currently depend on drm_framebuffer.h without
actually including it directly. All of those need to be fixed
up.

v2: Fix up msm some more
v2: Deal with ingenic and shmobile as well

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220614095449.29311-1-ville.syrjala@linux.intel.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>

fbdev: Rename pagelist to pagereflist for deferred I/O

Rename various instances of pagelist to pagereflist. The list now
stores pageref structures, so the new name is more appropriate.

In their write-back helpers, several fbdev drivers refer to the
pageref list in struct fb_deferred_io instead of using the one
supplied as argument to the function. Convert them over to the
supplied one. It's the same instance, so no change of behavior
occurs.

v4:
* fix commit message (Javier)

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-5-tzimmermann@suse.de

fbdev: Track deferred-I/O pages in pageref struct

Store the per-page state for fbdev's deferred I/O in struct
fb_deferred_io_pageref. Maintain a list of pagerefs for the pages
that have to be written back to video memory. Update all affected
drivers.

As with pages before, fbdev acquires a pageref when an mmaped page
of the framebuffer is being written to. It holds the pageref in a
list of all currently written pagerefs until it flushes the written
pages to video memory. Writeback occurs periodically. After writeback
fbdev releases all pagerefs and builds up a new dirty list until the
next writeback occurs.

Using pagerefs has a number of benefits.

For pages of the framebuffer, the deferred I/O code used struct
page.lru as an entry into the list of dirty pages. The lru field is
owned by the page cache, which makes deferred I/O incompatible with
some memory pages (e.g., most notably DRM's GEM SHMEM allocator).
struct fb_deferred_io_pageref now provides an entry into a list of
dirty framebuffer pages, freeing lru for use with the page cache.

Drivers also assumed that struct page.index is the page offset into
the framebuffer. This is not true for DRM buffers, which are located
at various offset within a mapped area. struct fb_deferred_io_pageref
explicitly stores an offset into the framebuffer. struct page.index
is now only the page offset into the mapped area.

These changes will allow DRM to use fbdev deferred I/O without an
intermediate shadow buffer.

v3:
* use pageref->offset for sorting
* fix grammar in comment
v2:
* minor fixes in commit message

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-3-tzimmermann@suse.de

fbdev: Put mmap for deferred I/O into drivers

The fbdev mmap function fb_mmap() unconditionally overrides the
driver's implementation if deferred I/O has been activated. This
makes it hard to implement mmap with anything but a vmalloc()'ed
software buffer. That is specifically a problem for DRM, where
video memory is maintained by a memory manager.

Leave the mmap handling to drivers and expect them to call the
helper for deferred I/O by thmeselves.

v4:
* unlock mm_lock in fb_mmap() error path (Dan)
v3:
* fix warning if fb_mmap is missing (kernel test robot)
v2:
* print a helpful error message if the defio setup is
incorrect (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220429100834.18898-2-tzimmermann@suse.de

iosys-map: Add offset to iosys_map_memcpy_to()

In certain situations it's useful to be able to write to an
offset of the mapping. Add a dst_offset to iosys_map_memcpy_to().

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Christian König <christian.koenig@amd.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220216174147.3073235-2-lucas.demarchi@intel.com

drm/fb-helper: Clip damage area horizontally

Clip the damage area horizontally if only a single scanline has been
changed. This is helpful to reduce the memcpy overhead for small writes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-6-tzimmermann@suse.de

drm/fb-helper: Clip damage area to written memory range

Write helpers used to mark the complete screen as dirty. This is
wasteful for writes that only change a small portion of the screen.
Fix the problem by computing the damaged area from the written
memory range and perform damage handling accordingly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-5-tzimmermann@suse.de

drm/fb-helper: Calculate damaged area in separate helper

Add drm_fb_helper_memory_range_to_clip(), a helper function that
accepts an linear range of video memory and converts it into a
rectangle. The computed rectangle describes the damaged area in
terms of scanlines and pixels per scanline.

While at it, make the code more readable by using struct drm_rect
and related helpers.

The code was previously part of the deferred I/O helpers, but is
also useful for damage handling of regular write operations. Update
the deferred I/O code to use the new function.

v2:
* rename helper (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-4-tzimmermann@suse.de

drm/fb-helper: Fix vertical damage clipping

Don't clip the damage rectangle against the viewport. This only
works if the viewport is located at the beginning of the video
memory and the video memory doesn't extend the screen (i.e., if
there's no overallocation).

Fbdev emulation transfers data from write operations into a
possible shadow buffer, then into a GEM buffer object, and finally
via graphics driver onto the screen.

If callers write outside the currently visible area, clipping the
damage rectangle against the viewport will loose these updates in
the shadow buffer and the fbdev's buffer object will contain stale
data. Panning the viewport to the stale area of the buffer will
display obsolete data.

Instead, mark all written areas as damaged, so that the damage
handler updates the buffer object from the shadow buffer for all
such areas. The graphics driver's later has the option of clipping
the damaged area against the viewport when updating the screen
from the buffer object.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-3-tzimmermann@suse.de

drm/fb-helper: Fix clip rectangle height

Computing the clip rectangle is prone to off-by-one errors when writes
happen near the end of a memory page. Point the end of the memory area
to the first trailing byte, so that (end - start) returns the area's
length.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209161617.3553-2-tzimmermann@suse.de

dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.

The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.

The conversion was mostly done with the following semantic patch:

@r1@
@@
- struct dma_buf_map
+ struct iosys_map

@r2@
@@
(
- DMA_BUF_MAP_INIT_VADDR
+ IOSYS_MAP_INIT_VADDR
|
- dma_buf_map_set_vaddr
+ iosys_map_set_vaddr
|
- dma_buf_map_set_vaddr_iomem
+ iosys_map_set_vaddr_iomem
|
- dma_buf_map_is_equal
+ iosys_map_is_equal
|
- dma_buf_map_is_null
+ iosys_map_is_null
|
- dma_buf_map_is_set
+ iosys_map_is_set
|
- dma_buf_map_clear
+ iosys_map_clear
|
- dma_buf_map_memcpy_to
+ iosys_map_memcpy_to
|
- dma_buf_map_incr
+ iosys_map_incr
)

@@
@@
- #include <linux/dma-buf-map.h>
+ #include <linux/iosys-map.h>

Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.

Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.

v2:
- Squash patches

v3:
- Fix wrong removal of dma-buf.h from MAINTAINERS
- Move documentation from dma-buf.rst to device-io.rst

v4:
- Change documentation title and level

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com

drm/fb-helper: Mark screen buffers in system memory with FBINFO_VIRTFB

Mark screen buffers in system memory with FBINFO_VIRTFB. Otherwise, fbdev
deferred I/O marks mmap'ed areas of system memory with VM_IO. (There's an
inverse relationship between the two flags.)

For shadow buffers, also set the FBINFO_READS_FAST hint.

v3:
* change FB_ to FBINFO_ in commit description
v2:
* updated commit description (Daniel)
* added Fixes tag

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: d536540f304c ("drm/fb-helper: Add generic fbdev emulation .fb_probe function")
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.19+
Link: https://patchwork.freedesktop.org/patch/msgid/20220201115305.9333-1-tzimmermann@suse.de

drm/fb-helper: Allocate shadow buffer of surface height

Allocating a shadow buffer of the height of the buffer object does
not support fbdev overallocation. Use surface height instead.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211110103702.374-7-tzimmermann@suse.de

Revert "drm/fb-helper: improve DRM fbdev emulation device names"

This reverts commit b3484d2b03e4c940a9598aa841a52d69729c582a.

That change attempted to improve the DRM drivers fbdev emulation device
names to avoid having confusing names like "simpledrmdrmfb" in /proc/fb.

But unfortunately, there are user-space programs such as pm-utils that
match against the fbdev names and so broke after the mentioned commit.

Since the names in /proc/fb are used by tools that consider it an uAPI,
let's restore the old names even when this lead to silly names like the
one mentioned above.

Fixes: b3484d2b03e4 ("drm/fb-helper: improve DRM fbdev emulation device names")
Reported-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211020165740.3011927-1-javierm@redhat.com

Revert "drm: cleanup: drm_modeset_lock_all() --> DRM_MODESET_LOCK_ALL_BEGIN()"

This reverts commit 7c5f2eecc21f44fba1b1f13ce09c2533db9d781a.

This patchset breaks on intel platforms and was previously NACK'd by
Ville.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Fernando Ramos <greenfoo@u92.eu>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211002154542.15800-13-sean@poorly.run

drm: cleanup: drm_modeset_lock_all() --> DRM_MODESET_LOCK_ALL_BEGIN()

As requested in Documentation/gpu/todo.rst, replace driver calls to
drm_modeset_lock_all() with DRM_MODESET_LOCK_ALL_BEGIN() and
DRM_MODESET_LOCK_ALL_END()

Signed-off-by: Fernando Ramos <greenfoo@u92.eu>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924064324.229457-5-greenfoo@u92.eu

drm/fbdev: Clamp fbdev surface size if too large

Clamp the fbdev surface size of the available maximumi height to avoid
failing to init console emulation. An example error is shown below.

bad framebuffer height 2304, should be >= 768 && <= 768
[drm] Initialized simpledrm 1.0.0 20200625 for simple-framebuffer.0 on minor 0
simple-framebuffer simple-framebuffer.0: [drm] *ERROR* fbdev: Failed to setup generic emulation (ret=-22)

This is especially a problem with drivers that have very small screen
sizes and cannot over-allocate at all.

v2:
* reduce warning level (Ville)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 11e8f5fd223b ("drm: Add simpledrm driver")
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reported-by: Amanoel Dawod <kernel@amanoeldawod.com>
Reported-by: Zoltán Kővágó <dirty.ice.hu@gmail.com>
Reported-by: Michael Stapelberg <michael+lkml@stapelberg.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.14+
Link: https://patchwork.freedesktop.org/patch/msgid/20211005070355.7680-1-tzimmermann@suse.de
Signed-off-by: Dave Airlie <airlied@redhat.com>

drm: Fix typo in comments

fix typo for drm

v1->v2:
respin with the change "iff ==> implies that"

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730132729.376-1-caihuoqing@baidu.com

drm/fb-helper: improve DRM fbdev emulation device names

Framebuffer devices that are registered by DRM drivers for fbdev emulation
have a "drmfb" suffix in their name. But makes them to be quite confusing
for drivers that already have "drm" in their name:

$ cat /proc/fb
0 rockchipdrmdrmfb

$ cat /proc/fb
0 simpledrmdrmfb

Also, there isn't a lot of value in adding these "drmfb" suffices to their
names, since users shouldn't really care if the FB devices were registered
by a real fbdev driver or a DRM driver using the fbdev emulation.

What programs should be interested about is if there's a DRM device, and
there are better ways to query that info than reading this procfs entry.

So let's just remove the suffix, which leads to much better device names:

$ cat /proc/fb
0 rockchipdrm

$ cat /proc/fb
0 simpledrm

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210525151313.3379622-1-javierm@redhat.com

drm/fb-helper: only unmap if buffer not null

drm_fbdev_cleanup() can be called when fb_helper->buffer is null, hence
fb_helper->buffer should be checked before calling
drm_client_buffer_vunmap(). This buffer is also checked in
drm_client_framebuffer_delete(), so we should also do the same thing for
drm_client_buffer_vunmap().

[ 199.128742] RIP: 0010:drm_client_buffer_vunmap+0xd/0x20
[ 199.129031] Code: 43 18 48 8b 53 20 49 89 45 00 49 89 55 08 5b 44 89 e0 41 5c 41 5d 41 5e 5d
c3 0f 1f 00 53 48 89 fb 48 8d 7f 10 e8 73 7d a1 ff <48> 8b 7b 10 48 8d 73 18 5b e9 75 53 fc ff 0
f 1f 44 00 00 48 b8 00
[ 199.130041] RSP: 0018:ffff888103f3fc88 EFLAGS: 00010282
[ 199.130329] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8214d46d
[ 199.130733] RDX: 1ffffffff079c6b9 RSI: 0000000000000246 RDI: ffffffff83ce35c8
[ 199.131119] RBP: ffff888103d25458 R08: 0000000000000001 R09: fffffbfff0791761
[ 199.131505] R10: ffffffff83c8bb07 R11: fffffbfff0791760 R12: 0000000000000000
[ 199.131891] R13: ffff888103d25468 R14: ffff888103d25418 R15: ffff888103f18120
[ 199.132277] FS: 00007f36fdcbb6a0(0000) GS:ffff88815b400000(0000) knlGS:0000000000000000
[ 199.132721] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 199.133033] CR2: 0000000000000010 CR3: 0000000103d26000 CR4: 00000000000006f0
[ 199.133420] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 199.133807] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 199.134195] Call Trace:
[ 199.134333] drm_fbdev_cleanup+0x179/0x1a0
[ 199.134562] drm_fbdev_client_unregister+0x2b/0x40
[ 199.134828] drm_client_dev_unregister+0xa8/0x180
[ 199.135088] drm_dev_unregister+0x61/0x110
[ 199.135315] mgag200_pci_remove+0x38/0x52 [mgag200]
[ 199.135586] pci_device_remove+0x62/0xe0
[ 199.135806] device_release_driver_internal+0x148/0x270
[ 199.136094] driver_detach+0x76/0xe0
[ 199.136294] bus_remove_driver+0x7e/0x100
[ 199.136521] pci_unregister_driver+0x28/0xf0
[ 199.136759] __x64_sys_delete_module+0x268/0x300
[ 199.137016] ? __ia32_sys_delete_module+0x300/0x300
[ 199.137285] ? call_rcu+0x3e4/0x580
[ 199.137481] ? fpregs_assert_state_consistent+0x4d/0x60
[ 199.137767] ? exit_to_user_mode_prepare+0x2f/0x130
[ 199.138037] do_syscall_64+0x33/0x40
[ 199.138237] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 199.138517] RIP: 0033:0x7f36fdc3dcf7

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Fixes: 763aea17bf57 ("drm/fb-helper: Unmap client buffer during shutdown")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210228044625.171151-1-ztong0001@gmail.com
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

drm: remove drm_fb_helper_modinit

drm_fb_helper_modinit has a lot of boilerplate for what is not very
simple functionality. Just open code it in the only caller using
IS_ENABLED and IS_MODULE, and skip the find_module check as a
request_module is harmless if the module is already loaded (and not
other caller has this find_module check either).

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>

drm/fb-helper: Add a FIXME that generic_setup is very confusing

I tried to fix this for real, but it's very sprawling and lots of
drivers get this mildly wrong one way or the other.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Simon Ser <contact@emersion.fr>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211161113.3350061-2-daniel.vetter@ffwll.ch

drm: add legacy support for using degamma for gamma

The DRM core handles legacy gamma-set ioctl by setting GAMMA_LUT and
clearing CTM and DEGAMMA_LUT.

This works fine on HW where we have either:

degamma -> ctm -> gamma -> out

or

ctm -> gamma -> out

However, if the HW has gamma table before ctm, the atomic property
should be DEGAMMA_LUT, and thus we have:

degamma -> ctm -> out

This is fine for userspace which sets gamma table using the properties,
as the userspace can check for the existence of gamma & degamma, but the
legacy gamma-set ioctl does not work.

Change the DRM core to use DEGAMMA_LUT instead of GAMMA_LUT when the
latter is unavailable.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211114237.213288-3-tomi.valkeinen@ti.com

drm/fb-helper: Add missed unlocks in setcmap_legacy()

setcmap_legacy() does not call drm_modeset_unlock_all() in some exits,
add the missed unlocks with goto to fix it.

Fixes: 964c60063bff ("drm/fb-helper: separate the fb_setcmap helper into atomic and legacy paths")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201203144248.418281-1-hslester96@gmail.com

drm/fb-helper: Acquire modeset lock around shadow-buffer flushing

Flushing the fbdev's shadow buffer requires vmap'ing the BO memory, which
in turn requires pinning the BO. While being pinned, the BO cannot be moved
into VRAM for scanout. Consequently, a concurrent modeset operation that
involves the fbdev framebuffer would likely fail.

Resolve this problem be acquiring the modeset lock of the planes that use
the fbdev framebuffer. On non-atomic drivers, also acquire the mode-config
lock. This serializes the flushing of the framebuffer with concurrent
modeset operations.

v2:
* only acquire struct drm_fb_helper.lock in damage blitter (Daniel,
Christian)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-11-tzimmermann@suse.de

drm/fb-helper: Copy dma-buf map before flushing shadow fb

Copy the vmap()'ed instance of struct dma_buf_map before modifying it,
in case the implementation of vunmap() depends on the exact address.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-10-tzimmermann@suse.de

drm/fb-helper: Restore damage area upon errors

If the damage handling fails, restore the damage area. The next invocation
of the damage worker will then perform the update.

v3:
* Use drm_WARN_ONCE() with an error message to print warning
v2:
* print a single warning if dirty callback fails (Daniel, Sebastian)
* update comment

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-9-tzimmermann@suse.de

drm/fb-helper: Move damage blit code and its setup into separate routine

Introduce a separate function for the blit code and its vmap setup. Done
in preparation of additional changes. No functional changes are made.

v3:
* Use drm_WARN_ONCE() with an error message to print warning
v2:
* print a single warning if damage blitter fails

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-8-tzimmermann@suse.de

drm/fb-helper: Separate shadow-buffer flushing and calling dirty callback

Flushing the shadow framebuffer and invoking the dirty callback are two
separate operations, so do them separately. The flush operation is paired
with calls to vmap and vunmap. They are not needed for the dirty callback,
which performs its own invocations if necessary.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-7-tzimmermann@suse.de

drm/fb-helper: Return early in damage worker

Returning early in the damage worker if no update is required. Makes the
code more readable. No functional changes are being made.

v3:
* s/dirty/damage in commit message (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-6-tzimmermann@suse.de

drm/fb-helper: Rename dirty worker to damage worker

The dirty worker handles all damage updates, instead of just calling
the framebuffer's dirty callback. Rename it to damage worker. Also
rename related variables accordingly. No functional changes are made.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-5-tzimmermann@suse.de

drm/fb-helper: Unmap client buffer during shutdown

The fbdev helper's generic probe function establishes a mapping for
framebuffers without shadow buffer. The clean-up function did not unmap
the buffer object. Add the unmap operation.

As fbdev devices are usally released during system shutdown, this has
not been a problem in practice.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-3-tzimmermann@suse.de

drm/fb-helper: Call dirty helper after writing to fbdev

If fbdev uses a shadow framebuffer, call the damage handler. Otherwise
the update might not make it to the screen.

v2:
* mark virtual screen as dirty (Ville)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 222ec45f4c69 ("drm/fb_helper: Support framebuffers in I/O memory")
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: virtualization@lists.linux-foundation.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201120102545.4047-2-tzimmermann@suse.de

drm/fb_helper: Use min_t() to handle size_t and unsigned long

On arm32:

drivers/gpu/drm/drm_fb_helper.c: In function ‘fb_read_screen_base’:
include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
...
drivers/gpu/drm/drm_fb_helper.c:2041:22: note: in expansion of macro ‘min’
2041 | size_t alloc_size = min(count, PAGE_SIZE);
| ^~~
drivers/gpu/drm/drm_fb_helper.c: In function ‘fb_write_screen_base’:
include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
...
drivers/gpu/drm/drm_fb_helper.c:2115:22: note: in expansion of macro ‘min’
2115 | size_t alloc_size = min(count, PAGE_SIZE);
| ^~~

Indeed, on 32-bit size_t is "unsigned int", not "unsigned long".

Fixes: 222ec45f4c69dfa8 ("drm/fb_helper: Support framebuffers in I/O memory")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201110090119.2667326-1-geert+renesas@glider.be

drm/fb_helper: Support framebuffers in I/O memory

At least sparc64 requires I/O-specific access to framebuffers. This
patch updates the fbdev console accordingly.

For drivers with direct access to the framebuffer memory, the callback
functions in struct fb_ops test for the type of memory and call the rsp
fb_sys_ of fb_cfb_ functions. Read and write operations are implemented
internally by DRM's fbdev helper.

For drivers that employ a shadow buffer, fbdev's blit function retrieves
the framebuffer address as struct dma_buf_map, and uses dma_buf_map
interfaces to access the buffer.

The bochs driver on sparc64 uses a workaround to flag the framebuffer as
I/O memory and avoid a HW exception. With the introduction of struct
dma_buf_map, this is not required any longer. The patch removes the rsp
code from both, bochs and fbdev.

v7:
* use min_t(size_t,) (kernel test robot)
* return the number of bytes read/written, if any (fbdev testcase)
v5:
* implement fb_read/fb_write internally (Daniel, Sam)
v4:
* move dma_buf_map changes into separate patch (Daniel)
* TODO list: comment on fbdev updates (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-11-tzimmermann@suse.de

drm/gem: Store client buffer mappings as struct dma_buf_map

Kernel DRM clients now store their framebuffer address in an instance
of struct dma_buf_map. Depending on the buffer's location, the address
refers to system or I/O memory.

Callers of drm_client_buffer_vmap() receive a copy of the value in
the call's supplied arguments. It can be accessed and modified with
dma_buf_map interfaces.

v6:
* don't call page_to_phys() on framebuffers in I/O memory;
warn instead (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-9-tzimmermann@suse.de

drm/fb-helper: Add locking to sysrq handling

We didn't take the kernel_fb_helper_lock mutex, which protects that
code. While at it, simplify the code
- inline the function (originally shared with kgdb I think)
- drop the error tracking and all the complications
- drop the pointless early out, it served nothing

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007133036.1541639-1-daniel.vetter@ffwll.ch

tty/sysrq: Extend the sysrq_key_table to cover capital letters

All slots in sysrq_key_table[] are either used, reserved or at least
commented with their intended use. This patch adds capital letter versions
available, which means adding 26 more entries.

For already existing SysRq operations the user presses Alt-SysRq-<key>, and
for the newly added ones Alt-Shift-SysRq-<key>.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20200818112825.6445-2-andrzej.p@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/drm_fb_helper: fix fbdev with sparc64

Recent kernels have been reported to panic using the bochs_drm
framebuffer under qemu-system-sparc64 which was bisected to
commit 7a0483ac4ffc ("drm/bochs: switch to generic drm fbdev emulation").

The backtrace indicates that the shadow framebuffer copy in
drm_fb_helper_dirty_blit_real() is trying to access the real
framebuffer using a virtual address rather than use an IO access
typically implemented using a physical (ASI_PHYS) access on SPARC.

The fix is to replace the memcpy with memcpy_toio() from io.h.

memcpy_toio() uses writeb() where the original fbdev code
used sbus_memcpy_toio(). The latter uses sbus_writeb().

The difference between writeb() and sbus_memcpy_toio() is
that writeb() writes bytes in little-endian, where sbus_writeb() writes
bytes in big-endian. As endian does not matter for byte writes they are
the same. So we can safely use memcpy_toio() here.

Note that this only fixes bochs, in general fbdev helpers still have
issues with mixing up system memory and __iomem space. Fixing that will
require a lot more work.

v3:
- Improved changelog (Daniel)
- Added FIXME to fbdev_use_iomem (Daniel)

v2:
- Added missing __iomem cast (kernel test robot)
- Made changelog readable and fix typos (Mark)
- Add flag to select iomem - and set it in the bochs driver

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reported-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reported-by: kernel test robot <lkp@intel.com>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200709193016.291267-1-sam@ravnborg.org
Link: https://patchwork.freedesktop.org/patch/msgid/20200725191012.GA434957@ravnborg.org

drm: fb-helper: Convert logging to drm_* functions.

Change logging information from dev_info() to drm_info().

Signed-off-by: Suraj Upadhyay <usuraj35@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/0d37c7a614eb0885f0f0bed18e48a4d26b345a8e.1594136880.git.usuraj35@gmail.com

drm/fb-helper: Fix vt restore

In the past we had a pile of hacks to orchestrate access between fbdev
emulation and native kms clients. We've tried to streamline this, by
always preferring the kms side above fbdev calls when a drm master
exists, because drm master controls access to the display resources.

Unfortunately this breaks existing userspace, specifically Xorg. When
exiting Xorg first restores the console to text mode using the KDSET
ioctl on the vt. This does nothing, because a drm master is still
around. Then it drops the drm master status, which again does nothing,
because logind is keeping additional drm fd open to be able to
orchestrate vt switches. In the past this is the point where fbdev was
restored, as part of the ->lastclose hook on the drm side.

Now to fix this regression we don't want to go back to letting fbdev
restore things whenever it feels like, or to the pile of hacks we've
had before. Instead try and go with a minimal exception to make the
KDSET case work again, and nothing else.

This means that if userspace does a KDSET call when switching between
graphical compositors, there will be some flickering with fbcon
showing up for a bit. But a) that's not a regression and b) userspace
can fix it by improving the vt switching dance - logind should have
all the information it needs.

While pondering all this I'm also wondering wheter we should have a
SWITCH_MASTER ioctl to allow race-free master status handover. But
that's for another day.

v2: Somehow forgot to cc all the fbdev people.

v3: Fix typo Alex spotted.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208179
Cc: shlomo@fastmail.com
Reported-and-Tested-by: shlomo@fastmail.com
Cc: Michel Dänzer <michel@daenzer.net>
Fixes: 64914da24ea9 ("drm/fbdev-helper: don't force restores")
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.7+
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Qiujun Huang <hqjagain@gmail.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200624092910.3280448-1-daniel.vetter@ffwll.ch

drm: constify sysrq_key_op

With earlier commits, the API no longer discards the const-ness of the
sysrq_key_op. As such we can add the notation.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-kernel@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://lore.kernel.org/r/20200513214351.2138580-8-emil.l.velikov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/fb-helper: Remove return value from drm_fbdev_generic_setup()

Generic fbdev emulation is a DRM client. Drivers should invoke the
setup function, but not depend on its success. Hence remove the return
value.

v3:
* document stricter requirements for call sequence
v2:
* warn if fbdev device has not been registered yet
* document the new behavior
* convert the existing warning to the new dev_ interface

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200408082641.590-11-tzimmermann@suse.de

drm/fb-helper: Add TODO for making drm_fb_helper_alloc_fbi fill apertures

Currently drivers using drm_fbdev_generic_setup() end up with a single
empty aperture in their fb_info struct.

Not having the proper info in the apertures list causes
register_framebuffer to not remove conflicting framebuffers,
which some drivers currently workaround by manually calling
drm_fb_helper_remove_conflicting_pci_framebuffers().

Add a TODO as a reminder that we need to fix this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200326151009.102377-1-hdegoede@redhat.com

drm: Remove unused arg from drm_fb_helper_init

The max connector argument for drm_fb_helper_init() isn't used anymore
hence remove it.

All the drm_fb_helper_init() calls are modified with below sementic
patch.

@@
expression E1, E2, E3;
@@
- drm_fb_helper_init(E1,E2, E3)
+ drm_fb_helper_init(E1,E2)

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305120434.111091-2-pankaj.laxminarayan.bharadiya@intel.com

drm/client: Rename _force to _locked

Plus extend the kerneldoc a bit to explain how this should be used.
With the previous patch to drop the force restore the main user of
this function is not emphasis on the "I hold the internal master lock
already" aspect, so rename the function to match.

Suggested by Noralf.

Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-4-daniel.vetter@ffwll.ch

drm/fbdev-helper: don't force restores

Instead check for master status, in case we've raced.

This is the last exception to the general rule that we restore fbcon
only when there's no master active. Compositors are supposed to drop
their master status before they switch to a different console back to
text mode (or just switch to text mode directly, without a vt switch).

This is known to break some subtests of kms_fbcon_fbt in igt, but they're
just wrong - it does a graphics/text mode switch for the vt without
updating the master status.

Also add a comment to the drm_client->restore hook that this is expected
going forward from all clients (there's currently just one).

v2: Also drop the force in pan_display

v3: Restore the _force to pan_display, this actually means _locked in that
path. Spotted by Noralf.

Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204150146.2006481-3-daniel.vetter@ffwll.ch

drm/fb-helper: Round up bits_per_pixel if possible

When userspace requests a video mode parameter value that is not
supported, frame buffer device drivers should round it up to a supported
value, if possible, instead of just rejecting it. This allows
applications to quickly scan for supported video modes.

Currently this rule is not followed for the number of bits per pixel,
causing e.g. "fbset -depth N" to fail, if N is smaller than the current
number of bits per pixel.

Fix this by returning an error only if bits per pixel is too large, and
setting it to the current value otherwise.

See also Documentation/fb/framebuffer.rst, Section 2 (Programmer's View
of /dev/fb*").

Fixes: 865afb11949e5bf4 ("drm/fb-helper: reject any changes to the fbdev")
Cc: stable@vger.kernel.org
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191230132734.4538-1-geert+renesas@glider.be

drm: Handle connector tile support only for modes that match tile size

DRM Fb driver expects multiple CRTCs if it sees connector->has_tile
is set, but we need to handle tile support and look for multiple CRTCs
only for the modes that match the tile size. The other modes should
be able to be displayed without tile support or uisng single CRTC.

This patch adds the check to match the tile size with requested mode
to handle the tile support.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191211212433.18185-1-manasi.d.navare@intel.com

drm/fb-helper: convert to drm device based logging

Prefer drm_dbg_kms(), drm_info(), and drm_err() over all other
logging. This is about KMS so switch to the KMS category while at it.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191210123050.8799-3-jani.nikula@intel.com

drm: constify fb ops across all drivers

Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/59b43629ac60031c5bbf961d8c49695019bc9c6f.1575390740.git.jani.nikula@intel.com

drm/fb-helper: don't preserve fb_ops across deferred IO use

Deferred IO now preserves the fb_ops.

v2: Remove the no-op vfree, drop a local var (Noralf)

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1eae0b23d4724d5702b886b6a061ec8219eb9284.1575022735.git.jani.nikula@intel.com

drm/fb-helper: Remove drm_fb_helper_unlink_fbi()

There are no callers of drm_fb_helper_unlink_fbi() left. Remove the
function.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191114125106.28347-3-tzimmermann@suse.de

drm/fb-helper: unexport drm_fb_helper_generic_probe

Not sure we don't yet have this as a patch somewhere ...

Motivation is that the automatic lifetime management of the generic fbdev
code is quite tricky, and it'll get even more tricky. Allowing drivers
to just use the fb_probe looks like a recipe for disaster.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191112175048.1581-1-daniel.vetter@ffwll.ch

drm/fb-helper: Remove drm_fb_helper_fbdev_{setup, teardown}()

Both functions are unused and can be removed. Drivers should use
drm_fbdev_generic_setup() instead.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191106124727.11641-3-tzimmermann@suse.de

drm/fb-helper: Remove drm_fb_helper_defio_init() and update docs

There are no users of drm_fb_helper_defio_init(), so we can remove
it. The documentation around defio support is a bit misleading and
should mention compatibility issues with SHMEM helpers. Clarify this.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191025092759.13069-2-tzimmermann@suse.de

drm/fb-helper: Include prototype for drm_fb_helper_modinit()

Sparse complains:
drivers/gpu/drm/drm_fb_helper.c:2409:12: warning: symbol 'drm_fb_helper_modinit' was not declared. Should it be static?

Include the header with the correct prototype.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190710125143.9965-1-ville.syrjala@linux.intel.com
Reviewed-by: Sean Paul <sean@poorly.run>

drm/fb-helper: Instanciate shadow FB if configured in device's mode_config

Generic framebuffer emulation uses a shadow buffer for framebuffers with
dirty() function. If drivers want to use the shadow FB without such a
function, they can now set prefer_shadow or prefer_shadow_fbdev in their
mode_config structures. The former flag is exported to userspace, the
latter flag is fbdev-only.

v3:
* only schedule dirty worker if fbdev uses shadow fb
* test shadow fb settings with boolean operators
* use bool for struct drm_mode_config.prefer_shadow_fbdev
* fix documentation comments

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/315834/
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

drm/fb-helper: Map DRM client buffer only when required

This patch changes DRM clients to not map the buffer by default. The
buffer, like any buffer object, should be mapped and unmapped when
needed.

An unmapped buffer object can be evicted to system memory and does
not consume video ram until displayed. This allows to use generic fbdev
emulation with drivers for low-memory devices, such as ast and mgag200.

This change affects the generic framebuffer console. HW-based consoles
map their console buffer once and keep it mapped. Userspace can mmap this
buffer into its address space. The shadow-buffered framebuffer console
only needs the buffer object to be mapped during updates. While not being
updated from the shadow buffer, the buffer object can remain unmapped.
Userspace will always mmap the shadow buffer.

v2:
* change DRM client to not map buffer by default
* manually map client buffer for fbdev with HW framebuffer

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/315830/
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

drm/fb-helper: Instanciate shadow FB if configured in device's mode_config

Generic framebuffer emulation uses a shadow buffer for framebuffers with
dirty() function. If drivers want to use the shadow FB without such a
function, they can now set prefer_shadow or prefer_shadow_fbdev in their
mode_config structures. The former flag is exported to userspace, the
latter flag is fbdev-only.

v3:
* only schedule dirty worker if fbdev uses shadow fb
* test shadow fb settings with boolean operators
* use bool for struct drm_mode_config.prefer_shadow_fbdev
* fix documentation comments

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/315834/

drm/fb-helper: Map DRM client buffer only when required

This patch changes DRM clients to not map the buffer by default. The
buffer, like any buffer object, should be mapped and unmapped when
needed.

An unmapped buffer object can be evicted to system memory and does
not consume video ram until displayed. This allows to use generic fbdev
emulation with drivers for low-memory devices, such as ast and mgag200.

This change affects the generic framebuffer console. HW-based consoles
map their console buffer once and keep it mapped. Userspace can mmap this
buffer into its address space. The shadow-buffered framebuffer console
only needs the buffer object to be mapped during updates. While not being
updated from the shadow buffer, the buffer object can remain unmapped.
Userspace will always mmap the shadow buffer.

v2:
* change DRM client to not map buffer by default
* manually map client buffer for fbdev with HW framebuffer

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/315830/

drm/client: Change drm_client_panel_rotation name

The drm_client_panel_rotation function has been used so far to set the
default rotation based on the panel orientation.

However, we can have more sources of information to make that decision,
starting with the command line that we will introduce later in this series.

Change the name to remove the panel mention.

Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8cb0f0d9569d41685bbf30a1538da6578cd2769b.1560783090.git-series.maxime.ripard@bootlin.com

drm: Reverse lock order in pan_display_legacy()

Acquiring drm_client_dev.modeset_mutex after the locks in drm_fb_helper.dev
creates a deadlock with drm_setup_crtcs() as shown below:

[ 4.959319] fbcon: radeondrmfb (fb0) is primary device
[ 4.993952] Console: switching to colour frame buffer device 240x67
[ 4.994040]
[ 4.994041] ======================================================
[ 4.994041] WARNING: possible circular locking dependency detected
[ 4.994042] 5.2.0-rc4-1-default+ #39 Tainted: G E
[ 4.994043] ------------------------------------------------------
[ 4.994043] systemd-udevd/369 is trying to acquire lock:
[ 4.994044] 00000000fb622acb (&client->modeset_mutex){+.+.}, at: drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
[ 4.994055]
[ 4.994055] but task is already holding lock:
[ 4.994055] 0000000028767ae4 (crtc_ww_class_mutex){+.+.}, at: drm_modeset_lock+0x42/0xf0 [drm]
[ 4.994072]
[ 4.994072] which lock already depends on the new lock.
[ 4.994072]
[ 4.994072]
[ 4.994072] the existing dependency chain (in reverse order) is:
[ 4.994073]
[ 4.994073] -> #3 (crtc_ww_class_mutex){+.+.}:
[ 4.994076] lock_acquire+0x9e/0x170
[ 4.994079] __ww_mutex_lock.constprop.18+0x97/0xf40
[ 4.994080] ww_mutex_lock+0x30/0x90
[ 4.994091] drm_modeset_lock+0x42/0xf0 [drm]
[ 4.994102] drm_modeset_lock_all_ctx+0x1f/0xe0 [drm]
[ 4.994113] drm_modeset_lock_all+0x5e/0x1a0 [drm]
[ 4.994163] intel_modeset_init+0x60b/0xda0 [i915]
..
[ 4.994253]
[ 4.994253] -> #2 (crtc_ww_class_acquire){+.+.}:
[ 4.994255] lock_acquire+0x9e/0x170
[ 4.994270] drm_modeset_acquire_init+0xcc/0x100 [drm]
[ 4.994280] drm_modeset_lock_all+0x44/0x1a0 [drm]
[ 4.994320] intel_modeset_init+0x60b/0xda0 [i915]
..
[ 4.994403]
[ 4.994403] -> #1 (&dev->mode_config.mutex){+.+.}:
[ 4.994405] lock_acquire+0x9e/0x170
[ 4.994408] __mutex_lock+0x62/0x8c0
[ 4.994413] drm_setup_crtcs+0x17c/0xc50 [drm_kms_helper]
[ 4.994418] __drm_fb_helper_initial_config_and_unlock+0x34/0x530 [drm_kms_helper]
[ 4.994450] radeon_fbdev_init+0x110/0x130 [radeon]
..
[ 4.994535]
[ 4.994535] -> #0 (&client->modeset_mutex){+.+.}:
[ 4.994537] __lock_acquire+0xa85/0xe90
[ 4.994538] lock_acquire+0x9e/0x170
[ 4.994540] __mutex_lock+0x62/0x8c0
[ 4.994545] drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
[ 4.994547] fb_pan_display+0x92/0x120
[ 4.994549] bit_update_start+0x1a/0x40
[ 4.994550] fbcon_switch+0x392/0x580
[ 4.994552] redraw_screen+0x12c/0x220
[ 4.994553] do_bind_con_driver.cold.30+0xe1/0x10d
[ 4.994554] do_take_over_console+0x113/0x190
[ 4.994555] do_fbcon_takeover+0x58/0xb0
[ 4.994557] notifier_call_chain+0x47/0x70
[ 4.994558] blocking_notifier_call_chain+0x44/0x60
[ 4.994559] register_framebuffer+0x231/0x310
[ 4.994564] __drm_fb_helper_initial_config_and_unlock+0x2fd/0x530 [drm_kms_helper]
[ 4.994590] radeon_fbdev_init+0x110/0x130 [radeon]
..

This problem was introduced in

d81294afe drm/fb-helper: Remove drm_fb_helper_crtc

Reversing the lock ordering in pan_display_legacy() fixes the issue.

Fixes: d81294afeecd ("drm/fb-helper: Remove drm_fb_helper_crtc")
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190611115716.7052-1-tzimmermann@suse.de

drm/fb-helper: Move out modeset config code

No functional changes, just moving code as-is and fixing includes.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190608152657.36613-4-noralf@tronnes.org

drm/fb-helper: Prepare to move out modeset config code

This prepares the modeset code so it can be moved out as-is in the next
patch.

v3: Remove stray newline

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190608152657.36613-3-noralf@tronnes.org

drm/fb-helper: Remove drm_fb_helper_connector

All drivers add all their connectors so there's no need to keep around an
array of available connectors. Instead we just put the useable (not
writeback) connectors in a temporary array using
drm_client_for_each_connector_iter() everytime we probe the outputs.
Other places where it's necessary to look at the connectors, we just
iterate over them using the same iterator function.

Rename functions which signature is changed since they will be moved to
drm_client in a later patch.

v6: Improve commit message (Sam Ravnborg)

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190608152657.36613-2-noralf@tronnes.org

drm/fb-helper: Move out commit code

Move the modeset commit code to drm_client_modeset.
No changes except exporting API.

v7: Export drm_client_panel_rotation() (Gerd Hoffmann)
v2: Move to drm_client_modeset.c instead of drm_client.c

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190531140117.37751-5-noralf@tronnes.org

drm/fb-helper: Prepare to move out commit code

This makes the necessary changes so the commit code can be moved out to
drm_client as-is in the next patch. It's split up to ease review.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190531140117.37751-4-noralf@tronnes.org

drm/fb-helper: Remove drm_fb_helper_crtc

struct drm_fb_helper_crtc is now just a wrapper around drm_mode_set so
use that directly instead and attach it as a modeset array onto
drm_client_dev. drm_fb_helper will use this array to store its modesets
which means it will always initialize a drm_client, but it will not
register the client (callbacks) unless it's the generic fbdev emulation.

Code will later be moved to drm_client, so add code there in a new file
drm_client_modeset.c with MIT license to match drm_fb_helper.c.

The modeset connector array size is hardcoded for the cloned case to avoid
having to pass in a value from the driver. A value of 8 is chosen to err
on the safe side. This means that the max connector argument for
drm_fb_helper_init() and drm_fb_helper_fbdev_setup() isn't used anymore,
a todo entry for this is added.

In pan_display_atomic() restore_fbdev_mode_force() is used instead of
restore_fbdev_mode_atomic() because that one will later become internal
to drm_client_modeset.

Locking order:
1. drm_fb_helper->lock
2. drm_master_internal_acquire
3. drm_client_dev->modeset_mutex

v6: Improve commit message (Sam Ravnborg)

v3:
- Use full drm_client_init/release for the modesets (Daniel Vetter)
- drm_client_for_each_modeset: use lockdep_assert_held (Daniel Vetter)
- Hook up to Documentation/gpu/drm-client.rst (Daniel Vetter)

v2:
- Add modesets array to drm_client (Daniel Vetter)
- Use a new file for the modeset code (Daniel Vetter)
- File has to be MIT licensed (Emmanuel Vadot)
- Add copyrights from drm_fb_helper.c

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190531140117.37751-3-noralf@tronnes.org

drm: drop use of drmP.h in drm/*

The use of the drmP.h header file is deprecated.
Remove use from all files in drm/*
so people do not look there and follow a bad example.

Build tested allyesconfig,allmodconfig on x86, arm etc.
Including alpha that is as always more challenging than
the rest.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Link: https://patchwork.freedesktop.org/patch/msgid/20190526173535.32701-8-sam@ravnborg.org

drm: Remove users of drm_format_info_plane_cpp

drm_format_info_plane_cpp() basically just returns the cpp array content
found in the drm_format_info structure.

Since it's pretty trivial, let's remove the function and have the users use
the array directly

Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/c0a78c87cd0410a1819edad2794ad06543c85bb5.1558002671.git-series.maxime.ripard@bootlin.com

drm/fourcc: Pass the format_info pointer to drm_format_plane_cpp

So far, the drm_format_plane_cpp function was operating on the format's
fourcc and was doing a lookup to retrieve the drm_format_info structure and
return the cpp.

However, this is inefficient since in most cases, we will have the
drm_format_info pointer already available so we shouldn't have to perform a
new lookup. Some drm_fourcc functions also already operate on the
drm_format_info pointer for that reason, so the API is quite inconsistent
there.

Let's follow the latter pattern and remove the extra lookup while being a
bit more consistent. In order to be extra consistent, also rename that
function to drm_format_info_plane_cpp and to a static function in the
header to match the current policy.

Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/32aa13e53dbc98a90207fd290aa8e79f785fb11e.1558002671.git-series.maxime.ripard@bootlin.com

drm/fb-helper: Fix drm_fb_helper_hotplug_event() NULL ptr argument

drm_fb_helper_hotplug_event() should tolerate the fb_helper argument being
NULL. Commit 03a9606e7fee ("drm/fb-helper: Avoid race with DRM userspace")
introduced a fb_helper dereference before the NULL check.
Fixup by moving the dereference after the NULL check.

Fixes: 03a9606e7fee ("drm/fb-helper: Avoid race with DRM userspace")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190515132925.48867-1-noralf@tronnes.org

drm/fb-helper: Remove drm_fb_helper_crtc->{x, y, desired_mode}

The values are already present in the modeset.

This is done in preparation for the removal of struct drm_fb_helper_crtc.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190506180139.6913-5-noralf@tronnes.org

drm/fb-helper: No need to cache rotation and sw_rotations

Getting rotation info is cheap so we can do it on demand.

This is done in preparation for the removal of struct drm_fb_helper_crtc.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190506180139.6913-4-noralf@tronnes.org

drm/fb-helper: Avoid race with DRM userspace

drm_fb_helper_is_bound() is used to check if DRM userspace is in control.
This is done by looking at the fb on the primary plane. By the time
fb-helper gets around to committing, it's possible that the facts have
changed.

Avoid this race by holding the drm_device->master_mutex lock while
committing. When DRM userspace does its first open, it will now wait
until fb-helper is done. The helper will stay away if there's a master.

Two igt tests fail with the new 'bail out if master' rule. Work around
this by relaxing this rule for drm_fb_helper_restore_fbdev_mode_unlocked()
until the tests have been fixed. Add todo entry for this.

Locking rule: Always take the fb-helper lock first.

v5: drm_fb_helper_restore_fbdev_mode_unlocked(): Use
restore_fbdev_mode_force()

v2:
- Remove drm_fb_helper_is_bound() (Daniel Vetter)
- No need to check fb_helper->dev->master in
drm_fb_helper_single_fb_probe(), restore_fbdev_mode() has the check.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190506180139.6913-3-noralf@tronnes.org

drm/fb-helper: Fix drm_fb_helper_firmware_config() NULL pointer deref

Non-atomic drivers like ast doesn't have connector->state set resulting
in a NULL pointer deref:

[ 29.609593] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[ 29.609619] Call Trace:
[ 29.609630] ? drm_helper_probe_single_connector_modes+0x27f/0x680
[ 29.609640] drm_setup_crtcs+0x431/0xd80 [drm_kms_helper]
[ 29.753065] __drm_fb_helper_initial_config_and_unlock+0x6f/0x6a0
[ 29.753160] ? drm_modeset_unlock_all+0x31/0x50 [drm]
[ 29.765758] ast_fbdev_init+0xa8/0xc0 [ast]
[ 29.765762] ast_driver_load.cold.7+0x2b3/0xe11 [ast]
[ 29.765775] drm_dev_register+0x111/0x150 [drm]

Fix by bailing out if the driver does not support atomic modesetting.

Fixes: 09ded8af57bc ("drm/i915/fbdev: Move intel_fb_initial_config() to fbdev helper")
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20190423145353.30158-1-noralf@tronnes.org

drm/fb: revert the i915 Actually configure untiled displays from master

This code moved in here in master, so revert it the same way.

This is the same revert as 9fa246256e09 ("Revert "drm/i915/fbdev:
Actually configure untiled displays"") in drm-fixes.

Signed-off-by: Dave Airlie <airlied@redhat.com>

drm/i915/fbdev: Move intel_fb_initial_config() to fbdev helper

It is generic code and having it in the helper will let other drivers
benefit from it.

One change was necessary assuming this to be true:
INTEL_INFO(dev_priv)->num_pipes == dev->mode_config.num_crtc

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: intel-gfx@lists.freedesktop.org
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190407165243.54043-4-noralf@tronnes.org

drm/client: Rename drm_client_add() to drm_client_register()

This is done to stay consistent with our naming scheme of
_register() = others can start calling us from any thread.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190403125658.32389-1-noralf@tronnes.org

drm/fb-helper: generic: Call drm_client_add() after setup is done

Hotplug can happen while drm_fbdev_generic_setup() is running so move
drm_client_add() call after setup is done to avoid
drm_fbdev_client_hotplug() running in two threads at the same time.

Fixes: 9060d7f49376 ("drm/fb-helper: Finish the generic fbdev emulation")
Cc: stable@vger.kernel.org
Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401141358.25309-1-noralf@tronnes.org

drm/fb-helper: dpms_legacy(): Only set on connectors in use

For each enabled crtc the functions sets dpms on all registered connectors.
Limit this to only doing it once and on the connectors actually in use.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Fixes: 023eb571a1d0 ("drm: correctly update connector DPMS status in drm_fb_helper")
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326175546.18126-3-noralf@tronnes.org

drm/fb-helper: Remove unused gamma_size variable

The gamma_size variable has not been used since
commit 4abe35204af8 ("drm/kms/fb: use slow work mechanism for normal hotplug also.")

While in the area move a comment back to its code block.
They got separated by
commit d50ba256b5f1 ("drm/kms: start adding command line interface using fb.").

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326175546.18126-2-noralf@tronnes.org

drm/fb-helper: Fixup fill_info cleanup

I forgot the !CONFIG_FBDEV case. Also some kerneldoc needed more
adjusting.

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190327125819.16478-1-daniel.vetter@ffwll.ch

drm/fb-helper: Unexport fill_{var,info}

Not used by drivers anymore.

v2: Rebase

Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326132008.11781-21-daniel.vetter@ffwll.ch

drm/fb_helper: set info->par in fill_info()

The fbdev emulation helpers pretty much assume that this is set.
Let's do it for everyone.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326132008.11781-3-daniel.vetter@ffwll.ch

drm/fb-helper: set fbi->fix.id in fill_info()

Looking at the oldest/most popular drivers ${driver}drmfb seems to be
the standard, except i915.ko went with "inteldrmfb". I guess renaming
that for consistency won't hurt, it definitely confused me when I
started with kms 10 years ago.

I hope this never became uapi ... worst case drivers can overwrite it
after having called fill_info().

Since subsequent patches change this for some drivers later on in the
series, here's the exhaustive list of where all fix.id is used:
- /proc/fb which prints the minor number and fix.id name.
- per-fb sysfs name file
- getfix ioctl, which is used by fbset only to print out the name when
dumping information
- lots and lots of places in dmesg, anytime anything happens with an
fbdev really

I think minimal to 0 chances that changing this will screw up a config
script or something, since outside of informational message it's not
used by anything to identify which fbdev maps to which minor. After
all the last fbset release is from 1999, and that predates even devfs
I think.

v2: Rebase and amend commit message, thanks to Ilia for pointing out
that this needs to be spelled out.

Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326132008.11781-2-daniel.vetter@ffwll.ch

drm/fb-helper: Add fill_info() functions

The fbdev split between fix and var information is kinda
pointless for drm drivers since everything is fixed: The fbdev
emulation doesn't support changing modes at all.

Create a new simplified helper and use it in the generic fbdev
helper code. Follow-up patches will beef it up more and roll
it out to all drivers.

v2: We need to keep sizes, since they might not match the fb dimensions
(Noralf)

v3: Fix typo in commit message and remove extraneous line in kerneldoc (Noralf)

Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326132008.11781-1-daniel.vetter@ffwll.ch

drm/fbdev: Make skip_vt_switch the default

KMS drivers really should all be able to restore their display state
on resume without fbcon helping out. So make this the default.

Since I'm not entirely foolish, make it only a default, which drivers
can still override. That way when the inevitable regression report
happens I can fix things up with a one-liner plus FIXME comment that
someone should fix up the suspend/resume code in that driver.

But at least all new drivers won't be broken by accident as soon as
you turn off fbcon because "suspend/resume worked when I tested it".

v2: Keep this for radeon because of

commit 18c437caa5b18a235dd65cec224eab54bebcee65
Author: Alex Deucher <alexander.deucher@amd.com>
Date: Tue Nov 14 17:19:29 2017 -0500

Revert "drm/radeon: dont switch vt on suspend"

Thanks to Michel Dänzer for pointing this one out.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Michel Dänzer <michel@daenzer.net>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Sandy Huang <hjc@rock-chips.com>
Cc: "Heiko Stübner" <heiko@sntech.de>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Samuel Li <Samuel.Li@amd.com>
Cc: "Michel Dänzer" <michel.daenzer@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Junwei Zhang <Jerry.Zhang@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Shirish S <shirish.s@amd.com>
Cc: Daniel Stone <daniels@collabora.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: intel-gfx@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Samuel Li <samuel.li@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181127173424.301-1-daniel.vetter@ffwll.ch

drm/fb: avoid setting 0 depth.

If the downscaling fails and we end up with a best_depth of 0,
then ignore it.

This actually works around a cascade of failure, but it the
simplest fix for now.

The scaling patch broke the udl driver, as the udl driver doesn't
expose planes at all, so gets the two default 32-bit formats, but
the udl driver then ask for 16bpp fbdev, and the scaling code falls
over.

This fixes the udl driver since the scaled depth support was added.

Fixes: f4bd542bcaee ("drm/fb-helper: Scale back depth to supported maximum")
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190315014621.21816-2-airlied@gmail.com

drm/fb-helper: generic: Don't take module ref for fbcon

It's now safe to let fbcon unbind automatically on fbdev unregister.
The crash problem was fixed in commit 2122b40580dd
("fbdev: fbcon: Fix unregister crash when more than one framebuffer")

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190210131039.52664-13-noralf@tronnes.org

drm: Trivial comment grammar cleanups

Most of these are just cases where code comments used contractions
(it's, who's) where they actually mean to use a possessive pronoun (its,
whose) or vice-versa.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190202012326.20096-1-matthew.d.roper@intel.com

drm/fb-helper: generic: Fix drm_fbdev_client_restore()

If fbdev setup has failed, lastclose will give a NULL pointer deref:

[ 77.794295] [drm:drm_lastclose]
[ 77.794414] [drm:drm_lastclose] driver lastclose completed
[ 77.794660] Unable to handle kernel NULL pointer dereference at virtual address 00000014
[ 77.809460] pgd = b376b71b
[ 77.818275] [00000014] *pgd=175ba831, *pte=00000000, *ppte=00000000
[ 77.830813] Internal error: Oops: 17 [#1] ARM
[ 77.840963] Modules linked in: mi0283qt mipi_dbi tinydrm raspberrypi_hwmon gpio_backlight backlight snd_bcm2835(C) bcm2835_rng rng_core
[ 77.865203] CPU: 0 PID: 527 Comm: lt-modetest Tainted: G C 5.0.0-rc1+ #1
[ 77.879525] Hardware name: BCM2835
[ 77.889185] PC is at restore_fbdev_mode+0x20/0x164
[ 77.900261] LR is at drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0x9c
[ 78.002446] Process lt-modetest (pid: 527, stack limit = 0x7a3d5c14)
[ 78.291030] Backtrace:
[ 78.300815] [<c04f2d0c>] (restore_fbdev_mode) from [<c04f4708>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0x9c)
[ 78.319095] r9:d8a8a288 r8:d891acf0 r7:d7697910 r6:00000000 r5:d891ac00 r4:d891ac00
[ 78.334432] [<c04f46b4>] (drm_fb_helper_restore_fbdev_mode_unlocked) from [<c04f47e8>] (drm_fbdev_client_restore+0x18/0x20)
[ 78.353296] r8:d76978c0 r7:d7697910 r6:d7697950 r5:d7697800 r4:d891ac00 r3:c04f47d0
[ 78.368689] [<c04f47d0>] (drm_fbdev_client_restore) from [<c051b6b4>] (drm_client_dev_restore+0x7c/0xc0)
[ 78.385982] [<c051b638>] (drm_client_dev_restore) from [<c04f8fd0>] (drm_lastclose+0xc4/0xd4)
[ 78.402332] r8:d76978c0 r7:d7471080 r6:c0e0c088 r5:d8a85e00 r4:d7697800
[ 78.416688] [<c04f8f0c>] (drm_lastclose) from [<c04f9088>] (drm_release+0xa8/0x10c)
[ 78.431929] r5:d8a85e00 r4:d7697800
[ 78.442989] [<c04f8fe0>] (drm_release) from [<c02640c4>] (__fput+0x104/0x1c8)
[ 78.457740] r8:d5ccea10 r7:d96cfb10 r6:00000008 r5:d74c1b90 r4:d8a8a280
[ 78.472043] [<c0263fc0>] (__fput) from [<c02641ec>] (____fput+0x18/0x1c)
[ 78.486363] r10:00000006 r9:d7722000 r8:c01011c4 r7:00000000 r6:c0ebac6c r5:d892a340
[ 78.501869] r4:d8a8a280
[ 78.512002] [<c02641d4>] (____fput) from [<c013ef1c>] (task_work_run+0x98/0xac)
[ 78.527186] [<c013ee84>] (task_work_run) from [<c010cc54>] (do_work_pending+0x4f8/0x570)
[ 78.543238] r7:d7722030 r6:00000004 r5:d7723fb0 r4:00000000
[ 78.556825] [<c010c75c>] (do_work_pending) from [<c0101034>] (slow_work_pending+0xc/0x20)
[ 78.674256] ---[ end trace 70d3a60cf739be3b ]---

Fix by using drm_fb_helper_lastclose() which checks if fbdev is in use.

Fixes: 9060d7f49376 ("drm/fb-helper: Finish the generic fbdev emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190125150300.33268-1-noralf@tronnes.org

drm/cma-helper: Remove unused fbdev code

CMA helper drivers have been converted to drm_fbdev_generic_setup()
so the fbdev code can be removed.

v3: Remove CMA specific conditional in the generic fbdev client

v2: Clean up the includes some more (Laurent)

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114121059.20704-1-noralf@tronnes.org

drm/fb-helper: Scale back depth to supported maximum

The following happened when migrating an old fbdev driver to DRM:

The Integrator/CP PL111 supports 16BPP but only ARGB1555/ABGR1555
or XRGB1555/XBGR1555 i.e. the maximum depth is 15.

This makes the initialization of the framebuffer fail since
the code in drm_fb_helper_single_fb_probe() assigns the same value
to sizes.surface_bpp and sizes.surface_depth. I.e. it simply assumes
a 1-to-1 mapping between BPP and depth, which is true in most cases
but not for this hardware that only support odd formats.

To support the odd case of a driver supporting 16BPP with only 15
bits of depth, this patch will make the code loop over the formats
supported on the primary plane on each CRTC managed by the FB
helper and cap the depth to the maximum supported on any primary
plane.

On the PL110 Integrator, this makes drm_mode_legacy_fb_format()
select DRM_FORMAT_XRGB1555 which is acceptable for this driver, and
thus we get framebuffer, penguin and console on the Integrator/CP.

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190110114049.10618-1-linus.walleij@linaro.org

drm/fb-helper: Ignore the value of fb_var_screeninfo.pixclock

Strict requirement of pixclock to be zero breaks support of SDL 1.2
which contains hardcoded table of supported video modes with non-zero
pixclock values[1].

To better understand which pixclock values are considered valid and how
driver should handle these values, I briefly examined few existing fbdev
drivers and documentation in Documentation/fb/. And it looks like there
are no strict rules on that and actual behaviour varies:

* some drivers treat (pixclock == 0) as "use defaults" (uvesafb.c);
* some treat (pixclock == 0) as invalid value which leads to
-EINVAL (clps711x-fb.c);
* some pass converted pixclock value to hardware (uvesafb.c);
* some are trying to find nearest value from predefined table
(vga16fb.c, video_gx.c).

Given this, I believe that it should be safe to just ignore this value if
changing is not supported. It seems that any portable fbdev application
which was not written only for one specific device working under one
specific kernel version should not rely on any particular behaviour of
pixclock anyway.

However, while enabling SDL1 applications to work out of the box when
there is no /etc/fb.modes with valid settings, this change affects the
video mode choosing logic in SDL. Depending on current screen
resolution, contents of /etc/fb.modes and resolution requested by
application, this may lead to user-visible difference (not always):
image will be displayed in a right way, but it will be aligned to the
left instead of center. There is no "right behaviour" here as well, as
emulated fbdev, opposing to old fbdev drivers, simply ignores any
requsts of video mode changes with resolutions smaller than current.

The easiest way to reproduce this problem is to install sdl-sopwith[2],
remove /etc/fb.modes file if it exists, and then try to run sopwith
from console without X. At least in Fedora 29, sopwith may be simply
installed from standard repositories.

[1] SDL 1.2.15 source code, src/video/fbcon/SDL_fbvideo.c, vesa_timings
[2] http://sdl-sopwith.sourceforge.net/

Signed-off-by: Ivan Mironov <mironov.ivan@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 79e539453b34e ("DRM: i915: add mode setting support")
Fixes: 771fe6b912fca ("drm/radeon: introduce kernel modesetting for radeon hardware")
Fixes: 785b93ef8c309 ("drm/kms: move driver specific fb common code to helper functions (v2)")
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108072353.28078-3-mironov.ivan@gmail.com

drm/fb-helper: Partially bring back workaround for bugs of SDL 1.2

SDL 1.2 sets all fields related to the pixel format to zero in some
cases[1]. Prior to commit db05c48197759 ("drm: fb-helper: Reject all
pixel format changing requests"), there was an unintentional workaround
for this that existed for more than a decade. First in device-specific DRM
drivers, then here in drm_fb_helper.c.

Previous code containing this workaround just ignores pixel format fields
from userspace code. Not a good thing either, as this way, driver may
silently use pixel format different from what client actually requested,
and this in turn will lead to displaying garbage on the screen. I think
that returning EINVAL to userspace in this particular case is the right
option, so I decided to left code from problematic commit untouched
instead of just reverting it entirely.

Here is the steps required to reproduce this problem exactly:
1) Compile fceux[2] with SDL 1.2.15 and without GTK or OpenGL
support. SDL should be compiled with fbdev support (which is
on by default).
2) Create /etc/fb.modes with following contents (values seems
not used, and just required to trigger problematic code in
SDL):

mode "test"
geometry 1 1 1 1 1
timings 1 1 1 1 1 1 1
endmode

3) Create ~/.fceux/fceux.cfg with following contents:

SDL.Hotkeys.Quit = 27
SDL.DoubleBuffering = 1

4) Ensure that screen resolution is at least 1280x960 (e.g.
append "video=Virtual-1:1280x960-32" to the kernel cmdline
for qemu/QXL).

5) Try to run fceux on VT with some ROM file[3]:

# ./fceux color_test.nes

[1] SDL 1.2.15 source code, src/video/fbcon/SDL_fbvideo.c,
FB_SetVideoMode()
[2] http://www.fceux.com
[3] Example ROM: https://github.com/bokuweb/rustynes/blob/master/roms/color_test.nes

Reported-by: saahriktu <mail@saahriktu.org>
Suggested-by: saahriktu <mail@saahriktu.org>
Cc: stable@vger.kernel.org
Fixes: db05c48197759 ("drm: fb-helper: Reject all pixel format changing requests")
Signed-off-by: Ivan Mironov <mironov.ivan@gmail.com>
[danvet: Delete misleading comment.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108072353.28078-2-mironov.ivan@gmail.com
Link: https://patchwork.freedesktop.org/patch/msgid/20190108072353.28078-2-mironov.ivan@gmail.com

drm/fb-helper: fix leaks in error path of drm_fb_helper_fbdev_setup

After drm_fb_helper_fbdev_setup calls drm_fb_helper_init,
"dev->fb_helper" will be initialized (and thus drm_fb_helper_fini will
have some effect). After that, drm_fb_helper_initial_config is called
which may call the "fb_probe" driver callback.

This driver callback may call drm_fb_helper_defio_init (as is done by
drm_fb_helper_generic_probe) or set a framebuffer (as is done by bochs)
as documented. These are normally cleaned up on exit by
drm_fb_helper_fbdev_teardown which also calls drm_fb_helper_fini.

If an error occurs after "fb_probe", but before setup is complete, then
calling just drm_fb_helper_fini will leak resources. This was triggered
by df2052cc922 ("bochs: convert to drm_fb_helper_fbdev_setup/teardown"):

[ 50.008030] bochsdrmfb: enable CONFIG_FB_LITTLE_ENDIAN to support this framebuffer
[ 50.009436] bochs-drm 0000:00:02.0: [drm:drm_fb_helper_fbdev_setup] *ERROR* fbdev: Failed to set configuration (ret=-38)
[ 50.011456] [drm] Initialized bochs-drm 1.0.0 20130925 for 0000:00:02.0 on minor 2
[ 50.013604] WARNING: CPU: 1 PID: 1 at drivers/gpu/drm/drm_mode_config.c:477 drm_mode_config_cleanup+0x280/0x2a0
[ 50.016175] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G T 4.20.0-rc7 #1
[ 50.017732] EIP: drm_mode_config_cleanup+0x280/0x2a0
...
[ 50.023155] Call Trace:
[ 50.023155] ? bochs_kms_fini+0x1e/0x30
[ 50.023155] ? bochs_unload+0x18/0x40

This can be reproduced with QEMU and CONFIG_FB_LITTLE_ENDIAN=n.

Link: https://lkml.kernel.org/r/20181221083226.GI23332@shao2-debian
Link: https://lkml.kernel.org/r/20181223004315.GA11455@al
Fixes: 8741216396b2 ("drm/fb-helper: Add drm_fb_helper_fbdev_setup/teardown()")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20181223005507.28328-1-peter@lekensteyn.nl

drm/fb-helper: generic: Fix setup error path

If register_framebuffer() fails during fbdev setup we will leak the
framebuffer, the GEM buffer and the shadow buffer for defio. This is
because drm_fb_helper_fbdev_setup() just calls drm_fb_helper_fini() on
error not taking into account that register_framebuffer() can fail.

Since the generic emulation uses DRM client for its framebuffer and
backing buffer in addition to a shadow buffer, it's necessary to open code
drm_fb_helper_fbdev_setup() to properly handle the error path.

Error cleanup is removed from .fb_probe and is handled by one function for
all paths.

Fixes: 9060d7f49376 ("drm/fb-helper: Finish the generic fbdev emulation")
Reported-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190105181846.26495-1-noralf@tronnes.org

drm/fb-helper: Fix typo in parameter description

Fix typo in parameter description.

Fixes: 4be9bd10e22d ("drm/fb_helper: Allow leaking fbdev smem_start")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1543905135-35293-1-git-send-email-weiyongjun1@huawei.com

drm/fb-helper: Blacklist writeback when adding connectors to fbdev

Writeback connectors do not produce any on-screen output and require
special care for use. Such connectors are hidden from enumeration in
DRM resources by default, but they are still picked-up by fbdev.
This makes rather little sense since fbdev is not really adapted for
dealing with writeback.

Moreover, this is also a source of issues when userspace disables the
CRTC (and associated plane) without detaching the CRTC from the
connector (which is hidden by default). In this case, the connector is
still using the CRTC, leading to am "enabled/connectors mismatch" and
eventually the failure of the associated atomic commit. This situation
happens with VC4 testing under IGT GPU Tools.

Filter out writeback connectors in the fbdev helper to solve this.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Maxime Ripard <maxime.ripard@bootlin.com>
Fixes: 935774cd71fe ("drm: Add writeback connector type")
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181115163248.21168-1-paul.kocialkowski@bootlin.com

drm/fourcc: Add char_per_block, block_w and block_h in drm_format_info

For some pixel formats .cpp structure in drm_format info it's not
enough to describe the peculiarities of the pixel layout, for example
tiled formats or packed formats at bit level.

What's implemented here is to add three new members to drm_format_info
that could describe such formats:

- char_per_block[3]
- block_w[3]
- block_h[3]

char_per_block will be put in a union alongside cpp, for transparent
compatibility with the existing format descriptions.

Regarding, block_w and block_h they are intended to be used through
their equivalent getters drm_format_info_block_width /
drm_format_info_block_height, the reason of the getters is to abstract
the fact that for normal formats block_w and block_h will be unset/0,
but the methods will be returning 1.

Additionally, convenience function drm_format_info_min_pitch had been
added that computes the minimum required pitch for a given pixel
format and buffer width.

Using that the following drm core functions had been updated to
generically handle both block and non-block formats:

- drm_fb_cma_get_gem_addr: for block formats it will just return the
beginning of the block.
- framebuffer_check: Use the newly added drm_format_info_min_pitch.
- drm_gem_fb_create_with_funcs: Use the newly added
drm_format_info_min_pitch.
- In places where is not expecting to handle block formats, like fbdev
helpers I just added some warnings in case the block width/height
are greater than 1.

Changes since v3:
- Add helper function for computing the minimum required pitch.
- Improve/cleanup documentation

Changes since v8:
- Fixed build on 32bits arm architectures, with:

- return DIV_ROUND_UP((u64)buffer_width * info->char_per_block[plane],
+ return DIV_ROUND_UP_ULL((u64)buffer_width * info->char_per_block[plane],

Reviewed-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alexandru Gheorghe <alexandru-cosmin.gheorghe@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181101170055.5433-1-alexandru-cosmin.gheorghe@arm.com

drm: fb-helper: Reject all pixel format changing requests

drm fbdev emulation doesn't support changing the pixel format at all,
so reject all pixel format changing requests.

Cc: stable@vger.kernel.org
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181003164538.5534-1-Eugeniy.Paltsev@synopsys.com

drm/fb_helper: Allow leaking fbdev smem_start

Since "drm/fb: Stop leaking physical address", the default behaviour of
the DRM fbdev emulation is to set the smem_base to 0 and pass the new
FBINFO_HIDE_SMEM_START flag.

The main reason is to avoid leaking physical addresse to user-space, and
it follows a general move over the kernel code to avoid user-space to
manipulate physical addresses and then use some other mechanisms like
dma-buf to transfer physical buffer handles over multiple subsystems.

But, a lot of devices depends on closed sources binaries to enable
OpenGL hardware acceleration that uses this smem_start value to
pass physical addresses to out-of-tree modules in order to render
into these physical adresses. These should use dma-buf buffers allocated
from the DRM display device instead and stop relying on fbdev overallocation
to gather DMA memory (some HW vendors delivers GBM and Wayland capable
binaries, but older unsupported devices won't have these new binaries
and are doomed until an Open Source solution like Lima finalizes).

Since these devices heavily depends on this kind of software and because
the smem_start population was available for years, it's a breakage to
stop leaking smem_start without any alternative solutions.

This patch adds a Kconfig depending on the EXPERT config and an unsafe
kernel module parameter tainting the kernel when enabled.

A clear comment and Kconfig help text was added to clarify why and when
this patch should be reverted, but in the meantime it's a necessary
feature to keep.

Cc: Dave Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Ben Skeggs <skeggsb@gmail.com>
Cc: Christian König <christian.koenig@amd.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Dave Airlie <airlied@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1538136355-15383-1-git-send-email-narmstrong@baylibre.com

drm/cma-helper: Fix crash in fbdev error path

Sergey Suloev reported a crash happening in drm_client_dev_hotplug()
when fbdev had failed to register.

[ 9.124598] vc4_hdmi 3f902000.hdmi: ASoC: Failed to create component debugfs directory
[ 9.147667] vc4_hdmi 3f902000.hdmi: vc4-hdmi-hifi <-> 3f902000.hdmi mapping ok
[ 9.155184] vc4_hdmi 3f902000.hdmi: ASoC: no DMI vendor name!
[ 9.166544] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
[ 9.173840] vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4])
[ 9.181029] vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
[ 9.188519] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
[ 9.195690] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.203523] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.215032] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.274785] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
[ 9.290246] [drm] Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0
[ 9.297464] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 9.304600] [drm] Driver supports precise vblank timestamp query.
[ 9.382856] vc4-drm soc:gpu: [drm:drm_fb_helper_fbdev_setup [drm_kms_helper]] *ERROR* Failed to set fbdev configuration
[ 10.404937] Unable to handle kernel paging request at virtual address 00330a656369768a
[ 10.441620] [00330a656369768a] address between user and kernel address ranges
[ 10.449087] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 10.454762] Modules linked in: brcmfmac vc4 drm_kms_helper cfg80211 drm rfkill smsc95xx brcmutil usbnet drm_panel_orientation_quirks raspberrypi_hwmon bcm2835_dma crc32_ce pwm_bcm2835 bcm2835_rng virt_dma rng_core i2c_bcm2835 ip_tables x_tables ipv6
[ 10.477296] CPU: 2 PID: 45 Comm: kworker/2:1 Not tainted 4.19.0-rc5 #3
[ 10.483934] Hardware name: Raspberry Pi 3 Model B Rev 1.2 (DT)
[ 10.489966] Workqueue: events output_poll_execute [drm_kms_helper]
[ 10.596515] Process kworker/2:1 (pid: 45, stack limit = 0x000000007e8924dc)
[ 10.603590] Call trace:
[ 10.606259] drm_client_dev_hotplug+0x5c/0xb0 [drm]
[ 10.611303] drm_kms_helper_hotplug_event+0x30/0x40 [drm_kms_helper]
[ 10.617849] output_poll_execute+0xc4/0x1e0 [drm_kms_helper]
[ 10.623616] process_one_work+0x1c8/0x318
[ 10.627695] worker_thread+0x48/0x428
[ 10.631420] kthread+0xf8/0x128
[ 10.634615] ret_from_fork+0x10/0x18
[ 10.638255] Code: 54000220 f9401261 aa1303e0 b4000141 (f9400c21)
[ 10.644456] ---[ end trace c75b4a4b0e141908 ]---

The reason for this is that drm_fbdev_cma_init() removes the drm_client
when fbdev registration fails, but it doesn't remove the client from the
drm_device client list. So the client list now has a pointer that points
into the unknown and we have a 'use after free' situation.

Split drm_client_new() into drm_client_init() and drm_client_add() to fix
removal in the error path.

Fixes: 894a677f4b3e ("drm/cma-helper: Use the generic fbdev emulation")
Reported-by: Sergey Suloev <ssuloev@orpaltech.com>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181001194536.57756-1-noralf@tronnes.org

drm/fb-helper: Improve error reporting in setup

Improve error reporting in drm_fb_helper_fbdev_setup() by printing the
error code. This is useful for drivers that choose to not fall over just
because fbdev doesen't work, but still wants clues to why it failed.
This way they don't have to provide an error message themselves.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180908134648.2582-2-noralf@tronnes.org

drm/fb-helper: Remove set but not used variable 'connector_funcs'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpu/drm/drm_fb_helper.c: In function 'drm_pick_crtcs':
drivers/gpu/drm/drm_fb_helper.c:2373:43: warning:
variable 'connector_funcs' set but not used [-Wunused-but-set-variable]

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1536722130-108819-1-git-send-email-yuehaibing@huawei.com

drm/fb: Stop leaking physical address

For buffer sharing, use dma-buf instead. We can't set smem_start to 0
unconditionally since that's used by the fbdev mmap default
implementation. And we have plenty of userspace which would like to
keep that working.

This might break legit userspace - if it does we need to look at a
case-by-cases basis how to handle that. Worst case I expect overrides
for only specific drivers, since anything remotely modern should be
using dma-buf/prime now (which is about 7 years old now for DRM
drivers).

This issue was uncovered because Noralf's rework to implement a
generic fb_probe also implements it's own fb_mmap callback. Which
means smem_start didn't have to be set anymore, which blew up some
blob in userspace rather badly.

Acked-by: Sean Paul <seanpaul@chromium.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180822085405.10787-4-daniel.vetter@ffwll.ch

drm/fb-helper: improve documentation and print warnings

Clarify the relation between drm_fb_helper_fbdev_setup/teardown. Clarify
requirements for the new generic fbdev emulation API and log some more
details in case the driver does something wrong. Fix related typos.

Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20180906221810.20170-5-peter@lekensteyn.nl
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

drm/fb-helper: Finish the generic fbdev emulation

This adds a drm_fbdev_generic_setup() function that sets up generic
fbdev emulation with client callbacks for restore, hotplug and
unregister.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703160354.59955-7-noralf@tronnes.org

drm/fb-helper: Add generic fbdev emulation .fb_probe function

This is the first step in getting generic fbdev emulation.
A drm_fb_helper_funcs.fb_probe function is added which uses the
DRM client API to get a framebuffer backed by a dumb buffer.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703160354.59955-3-noralf@tronnes.org

drm: Add drm_connector_for_each_possible_encoder()

Add a convenience macro for iterating connector->encoder_ids[].
Isolates the users from the implementation details.

Note that we don't seem to pass the file_priv down to drm_encoder_find()
because encoders apparently don't get leased. No idea why
drm_encoder_finc() even takes the file_priv actually.

Also use ARRAY_SIZE() when populating the array to avoid spreading
knowledge about the array size all over.

v2: Hide the drm_encoder_find() in the macro, and
rename the macro appropriately (Daniel)
v3: Fix kernel docs (Daniel)

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180628131315.14156-4-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/fb-helper: Eliminate the .best_encoder() usage

Instead of using the .best_encoder() hook to figure out whether a given
connector+crtc combo will work, let's instead do what userspace does and
just iterate over all the encoders for the connector, and then check
each crtc against each encoder's possible_crtcs bitmask.

v2: Avoid oopsing on NULL encoders (Daniel)
s/connector_crtc_ok/connector_has_possible_crtc/

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180628131315.14156-2-ville.syrjala@linux.intel.com

drm: Stop updating plane->crtc/fb/old_fb on atomic drivers

Stop playing around with plane->crtc/fb/old_fb with atomic
drivers. Make life a lot simpler when we don't have to do the
magic old_fb vs. fb dance around plane updates. That way we
can't risk plane->fb getting out of sync with plane->state->fb
and we're less likely to leak any refcounts as well.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180525185045.29689-14-ville.syrjala@linux.intel.com
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

drm/fb-helper: Fix typo on kerneldoc

Copypasta mistake.

Fixes: 742547b73d27 ("drm/fb_helper: Create wrappers for blit, copyarea and fillrect funcs")
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180524090105.21196-1-daniel.vetter@ffwll.ch

drm: Add aspect ratio parsing in DRM layer

Current DRM layer functions don't parse aspect ratio information
while converting a user mode->kernel mode or vice versa. This
causes modeset to pick mode with wrong aspect ratio, eventually
causing failures in HDMI compliance test cases, due to wrong VIC.

This patch adds aspect ratio information in DRM's mode conversion
and mode comparision functions, to make sure kernel picks mode
with right aspect ratio (as per the VIC).

Background:
This patch was once reviewed and merged, and later reverted due to
lack of DRM cap protection. This is a re-spin of this patch, this
time with DRM cap protection, to avoid aspect ratio information, when
the client doesn't request for it.

Review link: https://pw-emeril.freedesktop.org/patch/104068/
Background discussion: https://patchwork.kernel.org/patch/9379057/

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Lin, Jia <lin.a.jia@intel.com>
Signed-off-by: Akashdeep Sharma <akashdeep.sharma@intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com> (V2)
Reviewed-by: Jose Abreu <Jose.Abreu@synopsys.com> (V4)

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>

V3: modified the aspect-ratio check in drm_mode_equal as per new flags
provided by Ville. https://patchwork.freedesktop.org/patch/188043/
V4: rebase
V5: rebase
V6: As recommended by Ville, avoided matching of aspect-ratio in
drm_fb_helper, while trying to find a common mode among connectors
for the target clone mode.
V7: rebase
V8: rebase
V9: rebase
V10: rebase
V11: rebase
V12: rebase
V13: rebase
V14: rebase

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1525777785-9740-10-git-send-email-ankit.k.nautiyal@intel.com

drm: Remove now pointelss blob->data casts

Now that blob->data is void* again we don't need the casts anymore.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180223192506.29992-2-ville.syrjala@linux.intel.com
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/framebuffer: Print task that allocated the fb in debug info.

This is is very useful to finding sources of leaked framebufers.
The fbcon fb is annotated with [fbcon], to give it a better name
than kworker.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171220093545.613-3-maarten.lankhorst@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/fb-helper: Add drm_fb_helper_defio_init()

Add helper for initializing fbdev deferred I/O.

The cleanup could have happened in drm_fb_helper_fini(), but that would
have required me to set fb_info->fbdefio to NULL in a couple of drivers
before they call _fini() to avoid double defio cleanup. The problem is
that one of those is vboxvideo which lives in Greg's staging tree.
So I put the cleanup in drm_fb_helper_fbdev_teardown(), not perfect
but not that bad either.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171215175119.36181-6-noralf@tronnes.org

drm/fb-helper: Update DOC with new helpers

Promote new helpers for dealing with fbdev emulation.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171215175119.36181-5-noralf@tronnes.org

drm/fb-helper: Add drm_fb_helper_fbdev_setup/teardown()

Add helpers to setup and teardown fbdev emulation.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171215175119.36181-3-noralf@tronnes.org

drm/fb-helper: Fix potential NULL pointer dereference

fb_helper is being dereferenced before it is null checked,
hence there is a potential null pointer dereference.

Fix this by moving the pointer dereference after fb_helper
has been null checked.

This issue was detected with the help of Coccinelle.

Fixes: c777990fb45b ("drm/fb-helper: Handle function NULL argument")
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171205174628.GA31189@embeddedor.com

drm/fb-helper: Apply panel orientation connector prop to the primary plane, v6.

Apply the "panel orientation" drm connector prop to the primary plane so
that fbcon and fbdev using userspace programs display the right way up.

Changes in v3:
-Use a rotation member in struct drm_fb_helper_crtc and set that from
drm_setup_crtcs instead of looping over all crtc's to find the right one
later
-Since we now no longer look at rotation quirks directly in the fbcon
code, set fb_info.fbcon_rotate_hint when the panel is not mounted upright
and we cannot use hardware rotation

Changes in v4:
-Make drm_fb_helper_init() init drm_fb_helper_crtc.rotation to
DRM_MODE_ROTATE_0 for all crtcs, so that we do not end up setting the
plane_state's rotation to an invalid value for disabled crtcs
(caught by Fi.CI)

Changes in v5:
-Only use hardware (crtc primary plane) rotation for DRM_ROTATE_180,
90 / 270 degree rotation requires special handling which we lack atm
-Add a TODO comment for 90 / 270 degree hardware rotation
-Add some comments to better document the default case when mapping
sw_rotations to fbcon_rotate_hints

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=94894
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171125193553.23986-5-hdegoede@redhat.com

drm/fb_helper: Disable all crtc's when initial setup fails.

Some drivers like i915 start with crtc's enabled, but with deferred
fbcon setup they were no longer disabled as part of fbdev setup.
Headless units could no longer enter pc3 state because the crtc was
still enabled.

Fix this by calling restore_fbdev_mode when we would have called
it otherwise once during initial fbdev setup.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: ca91a2758fce ("drm/fb-helper: Support deferred setup")
Cc: <stable@vger.kernel.org> # v4.14+
Reported-by: Thomas Voegtle <tv@lio96.de>
Tested-by: Thomas Voegtle <tv@lio96.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171128111603.62757-1-maarten.lankhorst@linux.intel.com

drm/fb: add support for not enabling fbcon on non-desktop displays [v2]

We don't want fbcon to get used on non-desktop dislays,
don't pass them as enabled connectors to the fb helper setup.

This prevents my HMD from getting disorted fbcon, and from
affecting other displays console.

v2: Change description from non-standard to non-desktop

Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drm/fb-helper: Add .last_close and .output_poll_changed helpers

This adds helpers for the drm_driver->last_close and the
drm_mode_config_funcs->output_poll_changed callbacks.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030153951.56269-4-noralf@tronnes.org

drm: Add drm_device->fb_helper pointer

drm_fb_helper is *the* way of doing fbdev emulation so add a pointer to
struct drm_device. This makes it possible to add callback helpers for
.last_close and .output_poll_changed further reducing fbdev emulation
footprint in drivers. The pointer is set by drm_fb_helper_init() and
cleared by drm_fb_helper_fini().

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030153951.56269-3-noralf@tronnes.org

drm/fb-helper: Handle function NULL argument

Make functions tolerate that the drm_fb_helper argument is NULL.
This is useful for drivers that continue probing when fbdev emulation
fails and not having to do this check themselves.
Update docs for functions that already handles this.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030153951.56269-2-noralf@tronnes.org

drm: Replace kzalloc with kcalloc

Prefer kcalloc over kzalloc to allocate an array.
This patch fixes checkcpatch issue.

Signed-off-by: Harsha Sharma <harshasharmaiitr@gmail.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013073747.29877-1-harshasharmaiitr@gmail.com
Link: https://patchwork.freedesktop.org/patch/msgid/20171013073747.29877-1-harshasharmaiitr@gmail.com

drm/fb-helper: Avoid NULL ptr dereference in fb_set_suspend()

drm_fb_helper_resume_worker() uses fb_helper->fbdev to call
fb_set_suspend() which dereferences the pointer.
Move sync-canceling of the resume worker in drm_fb_helper_fini() before
setting fb_helper->fbdev to NULL. Move dirty_work as well.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1503940668-25883-2-git-send-email-noralf@tronnes.org

drm/fb-helper: pass physical dimensions to fbdev

The fbdev subsystem has a place for physical dimensions (width and height
in mm) that is readable by userspace. Since DRM also knows these
dimensions, pass this information to the fbdev device.

This has to be done in drm_setup_crtcs_fb() instead of drm_setup_crtcs()
because fb_helper->fbdev may be NULL in drm_setup_crtcs().

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1501863924-7154-1-git-send-email-david@lechnology.com

drm/fb-helper: add new drm_setup_crtcs_fb() function

This adds a new drm_setup_crtcs_fb() function to handle the parts of
drm_setup_crtcs() that touch fb_helper->fb and fb_helper->fbdev. When
drm_setup_crtcs() is called during initialization, these fields are NULL
because they have not been allocated yet.

There is currently a hack at the end of drm_fb_helper_single_fb_probe()
that sets fb_helper->fb, so it is moved to the new drm_setup_crtcs_fb()
function.

This is also done in preparation for addition setup that requires access
to fb_helper->fbdev.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1501777149-8310-2-git-send-email-david@lechnology.com

drm/fb: Fix pointer dereference before null check.

fb_crtc is used before a null check, so move the use after the null check.

This was just identified by inspection. I haven't actually observed a crash
here, so it is possible that the null check could be unnecessary.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1501696813-8807-1-git-send-email-david@lechnology.com

drm/fb-helper: Support deferred setup

FB helper code falls back to a 1024x768 mode if no outputs are connected
or don't report back any modes upon initialization. This can be annoying
because outputs that are added to FB helper later on can't be used with
FB helper if they don't support a matching mode.

The fallback is in place because VGA connectors can happen to report an
unknown connection status even when they are in fact connected.

Some drivers have custom solutions in place to defer FB helper setup
until at least one output is connected. But the logic behind these
solutions is always the same and there is nothing driver-specific about
it, so a better alterative is to fix the FB helper core and add support
for all drivers automatically.

This patch adds support for deferred FB helper setup. It checks all the
connectors for their connection status, and if all of them report to be
disconnected marks the FB helper as needing deferred setup. Whet setup
is deferred, the FB helper core will automatically retry setup after a
hotplug event, and it will keep trying until it succeeds.

v2: Rebase onto my entirely reworked fbdev helper locking. One big
difference is that this version again drops&reacquires the fbdev lock
(which is now fb_helper->lock, but before this patch series it was
mode_config->mutex), because register_framebuffer must be able to
recurse back into fbdev helper code for the initial screen setup.

v3: __drm_fb_helper_initial_config must hold fb_helper->lock upon
return, I've fumbled that in the deferred setup case (Liviu).

v4: I was blind, redo this all. __drm_fb_helper_initial_config
shouldn't need to reacquire fb_helper->lock, that just confuses
callers. I myself got confused by kernel_fb_helper_lock and somehow
thought it's the same as fb_helper->lock. Tsk.

Also simplify the logic a bit (we don't need two functions to probe
connectors), we can stick much closer to the existing code. And update
some comments I've spotted that are outdated.

v5: Don't pass -EAGAIN to drivers, it's just an internal error code
(Liviu).

v6: Add _and_unlock suffix to clarify locking (Maarten)

Cc: Liviu Dudau <liviu@dudau.co.uk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com> (v1)
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Reviewed-by: Liviu Dudau <liviu@dudau.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170706130023.28417-3-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/fb-helper: separate the fb_setcmap helper into atomic and legacy paths

The legacy path implements setcmap in terms of crtc .gamma_set.

The atomic path implements setcmap by directly updating the crtc gamma_lut
property.

This has a couple of benefits:
- it makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
completely obsolete. They are now unused and subject for removal.
- atomic drivers that support clut modes get fbdev support for those from
the drm core. This includes atmel-hlcdc, but perhaps others as well?

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170713162538.22788-4-peda@axentia.se

drm/fb-helper: remove drm_fb_helper_save_lut_atomic

drm_fb_helper_save_lut_atomic is redundant since the .gamma_store is
now always kept up to date by drm_fb_helper_setcmap.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1499164632-5582-4-git-send-email-peda@axentia.se

drm/fb-helper: keep the .gamma_store updated in drm_fb_helper_setcmap

I think the gamma_store can end up invalid on error. But the way I read
it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
this pesky legacy fbdev stuff be any better?

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1499164632-5582-3-git-send-email-peda@axentia.se

drm/fb-helper: factor out pseudo-palette

The pseudo-palette has nothing to do with the crtc, so move it
out of the crtc loop and update the palette once, then break out
early.

Signed-off-by: Peter Rosin <peda@axenita.se>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1499164632-5582-2-git-send-email-peda@axentia.se

drm/fb-helper: Split dpms handling into legacy and atomic paths

Like with panning and modesetting, and like with those, stick with
simple drm_modeset_locking_all for the legacy path, and the full
atomic dance for atomic drivers.

This means a bit more boilerplate since setting up the atomic state
machinery is rather verbose, but then this is shared code for 30+
drivers or so, so meh.

After this patch there's only the LUT/cmap path which is still using
drm_modeset_lock_all for an atomic driver. But Peter is already
locking into reworking that, so I'll leave that code as-is for now.

v2: Squash in patches from Maarten to unify all the various atomic
paths into just one atomic update function for fbdev overall. On top
do one s/restore_fbdev_mode/restore_fbdev_mode_atomic/ so that we have
all-atomic callchains after the first check.

Cc: Peter Rosin <peda@axentia.se>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-10-daniel.vetter@ffwll.ch

drm/fb-helper: Stop using mode_config.mutex for internals

Those are now all protected using fb_helper->lock.

v2: We still need to hold mode_config.mutex right around calling
connector->fill_modes.

v3: I forgot to hold mode_config.mutex while looking at
connector->status and the mode list. Also, we need to patch up the
i915 ->initial_config callback to grab the locks it needs to inspect
the modeset state recovered from the fw.

v4: Don't reorder the probe too much (Ville).

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170705045629.31265-1-daniel.vetter@ffwll.ch

drm/fb-helper: Push locking into restore_fbdev_mode_atomic|legacy

Same game as with the panning function, use drm_modeset_lock_all for
legacy paths, and a proper acquire ctx w/w mutex dance for atomic.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-8-daniel.vetter@ffwll.ch

drm/fb-helper: Push locking into pan_display_atomic|legacy

For the legacy path we'll keep drm_modeset_lock_all, for the atomic
one we drop the use of the magic implicit context and wire it up
properly.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-7-daniel.vetter@ffwll.ch

drm/fb-helper: Drop locking from the vsync wait ioctl code

Like with the drm-native vblank wait ioctl we can entirely rely on the
spinlocks in drm_vblank.c, no need at all to take expensive mutexes.
The only reason we had to take mode_config.mutex was to protect the
fbdev helper's data-structures, but that's now done by
fb_helper->lock.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-6-daniel.vetter@ffwll.ch

drm/fb-helper: Push locking in fb_is_bound

That function only needs to take the individual crtc locks, not all
the kms locks. Push down the locking and then minimize it.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-5-daniel.vetter@ffwll.ch

drm/fb-helper: Add top-level lock

Introduce a new top-level lock for the FB helper code. This will allow
better locking granularity and avoid the need to abuse modeset locking
for this purpose instead.

This patch just adds the new lock everywhere we currently grab
mode_config->mutex (explicitly, or through drm_modeset_lock_all).
Follow-up patches will push the kms locking down into only the places
that need it.

v2:
- use lockdep_assert_held
- use drm_fb_helper_for_each_connector where possible
- use the new top-level lock consistently, i.e. in all the places
we're currently acquiring mode_config.mutex.
- small polish to the kerneldoc

Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com> (v1)
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-4-daniel.vetter@ffwll.ch

drm/fb-helper: Push down modeset lock into FB helpers

Move the modeset locking from drivers into FB helpers.

v2: Also handle intel_connector_add_to_fbdev.

v3: Prevent race in intel_dp_mst with ->detect (Maarten)

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com> (v1)
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170704151833.17304-2-daniel.vetter@ffwll.ch

drm/fb-helper: Remove drm_mode_config_fb.

Remove drm_mode_config_fb, I don't see the point of it.
To make it clear that it's ok to use plane->fb directly,
move up drm_drv_uses_atomic_modeset so the code is skipped for atomic
drivers that require plane_state->fb.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170703115106.18783-1-maarten.lankhorst@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Add DRM_MODE_ROTATE_ and DRM_MODE_REFLECT_ to UAPI

Add DRM_MODE_ROTATE_ and DRM_MODE_REFLECT_ defines to the UAPI
as a convenience.

Ideally the DRM_ROTATE_ and DRM_REFLECT_ property ids are looked up
through the atomic API, but realizing that userspace is likely to take
shortcuts and assume that the enum values are what is sent over the
wire.

As a result these defines are provided purely as a convenience to
userspace applications.

Changes since v3:
- Switched away from past tense in comments
- Add define name change to previously mis-spelled DRM_REFLECT_X comment
- Improved the comment for the DRM_MODE_REFLECT_<axis> comment

Changes since v2:
- Changed define prefix from DRM_MODE_PROP_ to DRM_MODE_
- Fix compilation errors
- Changed comment formatting
- Deduplicated comment lines
- Clarified DRM_MODE_PROP_REFLECT_ comment

Changes since v1:
- Moved defines from drm.h to drm_mode.h
- Changed define prefix from DRM_ to DRM_MODE_PROP_
- Updated uses of the defines to the new prefix
- Removed include from drm_rect.c
- Stopped using the BIT() macro

Signed-off-by: Robert Foss <robert.foss@collabora.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170519205017.23307-2-robert.foss@collabora.com

format-security: move static strings to const

While examining output from trial builds with -Wformat-security enabled,
many strings were found that should be defined as "const", or as a char
array instead of char pointer. This makes some static analysis easier,
by producing fewer false positives.

As these are all trivial changes, it seemed best to put them all in a
single patch rather than chopping them up per maintainer.

Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Jes Sorensen <jes@trained-monkey.org> [runner.c]
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
Cc: Salil Mehta <salil.mehta@huawei.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kejian Yan <yankejian@huawei.com>
Cc: Daode Huang <huangdaode@hisilicon.com>
Cc: Qianqian Xie <xieqianqian@huawei.com>
Cc: Philippe Reynes <tremyfr@gmail.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Christian Gromm <christian.gromm@microchip.com>
Cc: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Cc: Jason Litzinger <jlitzingerdev@gmail.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drm/fb-helper: Extract _legacy kms functions

The goal is to push all the kms locking down into these separate
_atomic and _legacy functions, so that we can correctly pass the
acquire ctx into all atomic drivers. Instead of playing games with
hidden ctx in mode_config.acquire_ctx. All the fbdev state will be
protected by a new fbdev private lock that Thierry is working on.

This here is just prep by creating a clean split between atomic and
legacy paths, which also simplifies the control flow a bit.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-16-daniel.vetter@ffwll.ch

drm: Add acquire ctx to ->gamma_set hook

Atomic helpers really want this instead of the hacked-up legacy
backoff trick, which unfortunately prevents drivers from using their
own private drm_modeset_locks.

Aside: There's a few atomic drivers (nv50, vc4, soon vmwgfx) which
don't yet use the new atomic color mgmt/gamma table stuff. Would be
nice if they could switch over and just hook up
drm_atomic_helper_legacy_gamma_set() instead.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Sinclair Yeh <syeh@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Eric Anholt <eric@anholt.net>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-13-daniel.vetter@ffwll.ch

drm/fb-helper: Give up on kgdb for atomic drivers

It just doesn't work. It probably stopped working way, way before that
(e.g. i915 grabbed random mutexes all over in modeset code at least
since gen6), but with atomic and all the ww_mutex stuff it's indeed
hopeless.

Remove ->mode_set_base_atomic from the 2 atomic drivers (i915 and
nouveau) that still had one (both had dummy implementations already
anyway), and shunt atomic drivers in the helpers debug_enter/leave
functions.

I'll leave the code in for radeon and amdgpu, but I think as soon as
amdgpu is atomic we should think about just ripping it out. Only
having it around for radeon and pre-nv50 is rather pointless. This
would also allow us to nuke all that code from fbdev.

Funny part is that _all_ kms drivers set this hook, despite that no
one else provides the required ->mode_set_base_atomic implementation.

The reason I'm jumping on this is that I want to wire up a full
acquire ctx for the benefit of atomic drivers, everywhere. And the
debug_enter/leave implementations call ->gamma_set. And there's just
no way ever we can create an acquire_ctx in the nmi context of kgdb.

Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-11-daniel.vetter@ffwll.ch

drm/fb-helper: Improve code readability

Add a couple of temporary variables and use shorter names for existing
variables in drm_fb_helper_add_one_connector() for better readability.

Tested-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170329144401.1804-4-thierry.reding@gmail.com

drm/fb-helper: Reshuffle code for subsequent patches

An unlocked version of the drm_fb_helper_add_one_connector() function
will be added in a subsequent patch. Reshuffle the code separately to
make the diff more readable later on.

Tested-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170329144401.1804-3-thierry.reding@gmail.com

drm/fb-helper: Cleanup checkpatch warnings

Fix up a couple of checkpatch warnings, such as whitespace or coding
style issues.

Tested-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170329144401.1804-2-thierry.reding@gmail.com

drm/fb-helper: Allow var->x/yres(_virtual) < fb->width/height again

Otherwise this can also prevent modesets e.g. for switching VTs, when
multiple monitors with different native resolutions are connected.

The depths must match though, so keep the != test for that.

Also update the DRM_DEBUG output to be slightly more accurate, this
doesn't only affect requests from userspace.

Bugzilla: https://bugs.freedesktop.org/99841
Fixes: 865afb11949e ("drm/fb-helper: reject any changes to the fbdev")
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170323085326.20185-1-michel@daenzer.net

drm/fb-helper: implement ioctl FBIO_WAITFORVSYNC

Implement legacy framebuffer ioctl FBIO_WAITFORVSYNC in the generic
framebuffer emulation driver. Legacy framebuffer users like non kms/drm
based OpenGL(ES)/EGL implementations may require the ioctl to
synchronize drawing or buffer flip for double buffering. It is tested on
the i.MX6.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: Rename connector list iterator API

Currently the functions that initialize and tear down a connector
iterator use the _get() and _put() suffixes. However, these suffixes
are typically used by reference counting functions.

Make these function names a little more consistent by changing the
suffixes to _begin() and _end(), which is a fairly common pattern in
the rest of the Linux kernel.

Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-8-thierry.reding@gmail.com

drm: Introduce drm_connector_{get,put}()

For consistency with other reference counting APIs in the kernel, add
drm_connector_get() and drm_connector_put() functions to reference count
connectors.

Compatibility aliases are added to keep existing code working. To help
speed up the transition, all the instances of the old functions in the
DRM core are already replaced in this commit.

The existing semantic patch for mode object reference count conversion
is extended for these new helpers.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-4-thierry.reding@gmail.com

drm/fb-helper: Add multi buffer support for cma fbdev

This patch add a config to support to create multi buffer for cma fbdev.
Such as double buffer and triple buffer.

Cma fbdev is convient to add a legency fbdev. And still many Android
devices use fbdev now and at least double buffer is needed for these
Android devices, so that a buffer flip can be operated. It will need
some time for Android device vendors to abondon legency fbdev. So multi
buffer for fbdev is needed.

Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org>
[s.christ@phytec.de: Picking patch from
https://lkml.org/lkml/2015/9/14/188]
Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/075ffb50cc16ab055b5d47b30163401bb356ab51.1487175046.git-series.maxime.ripard@free-electrons.com

drm: Cancel drm_fb_helper_resume_work on unload

We can not allow the worker to run after its fbdev, or even the module,
has been removed.

Fixes: cfe63423d9be ("drm/fb-helper: Add drm_fb_helper_set_suspend_unlocked()")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170207124956.14954-2-chris@chris-wilson.co.uk

drm: Cancel drm_fb_helper_dirty_work on unload

We can not allow the worker to run after its fbdev, or even the module,
has been removed.

Fixes: eaa434defaca ("drm/fb-helper: Add fb_deferred_io support")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170207124956.14954-1-chris@chris-wilson.co.uk

drm/fb-helper: Automatically clean up fb_info

Noticed that everyone duplicates the same logic here and we could safe
a few lines per driver. Yay for lots of drivers to make such tiny
refactors worth-while!

v2: Forgot to git add everything :(

v3: Actually remove release_fbi (Sean, Emil, Chris) ...

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170207161603.17611-1-daniel.vetter@ffwll.ch

drm/fb-helper: Explain unload sequence a bit better

While reviewing Chris' patches to properly cancel our async workers I
checked that this happens after the fbdev is already unregistered.
That's the case, but I found a small gap in our docs, fill that in.

Note that I don't explain what release_fbi does, because that function
will disappear in the next patch ...

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170207141050.1129-1-daniel.vetter@ffwll.ch

drm: Rely on mode_config data for fb_helper initialization

Instead of receiving the num_crts as a parameter, we can read it
directly from the mode_config structure. I audited the drivers that
invoke this helper and I believe all of them initialize the mode_config
struct accordingly, prior to calling the fb_helper.

I used the following coccinelle hack to make this transformation, except
for the function headers and comment updates. The first and second
rules are split because I couldn't find a way to remove the unused
temporary variables at the same time I removed the parameter.

// <smpl>
@r@
expression A,B,D,E;
identifier C;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)

@@
expression A,B,C,D,E;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)

@@
identifier r.C;
type T;
expression V;
@@
- T C;
<...
when != C
- C = V;
...>
// </smpl>

Changes since v1:
- Rebased on top of the tip of drm-misc-next.
- Remove mention to sti since a proper fix got merged.

Suggested-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170202162640.27261-1-krisman@collabora.co.uk

drm/kms-helpers: Use recommened kerneldoc for struct member refs

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Comments from Gustavo.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Rewiewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-2-daniel.vetter@ffwll.ch

drm: remove useless parameters from drm_pick_cmdline_mode function

drm_pick_cmdline_mode width and height parameters are useless.
Just remove them.

Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483721084-20278-2-git-send-email-vincent.abriou@st.com

drm: Wrap the check for atomic_commit implementation

This check is useful for drivers that do not have DRIVER_ATOMIC set but
have atomic modesetting internally implemented. Wrap the check into a
function since this is used in many places and as a bonus, the function
name helps to document what the check is for.

v2:
Change return type to bool (Ville)
Move the function drm_atomic.h (Daniel)
Fixed comment marker for documentation

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
[danvet: Move back to drmP.h because include hell.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1482396643-32456-1-git-send-email-dhinakaran.pandiyan@intel.com

drm: Convert all helpers to drm_connector_list_iter

Mostly nothing special (except making sure that really all error paths
and friends call iter_put).

v2: Don't forget the raw connector_list walking in
drm_helper_move_panel_connectors_to_head. That one unfortunately can't
be converted to the iterator helpers, but since it's just some list
splicing best to just wrap the entire thing up in one critical
section.

v3: Bail out after iter_put (Harry).

Cc: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161215155843.13408-1-daniel.vetter@ffwll.ch

drm: Nuke fb->bits_per_pixel

Replace uses of fb->bits_per_pixel with fb->format->cpp[0]*8.
Less duplicated information is a good thing.

Note that I didn't put parens around the cpp*8 in the below cocci script,
on account of not wanting spurious parens all over the place. Instead I
did the unsafe way, and tried to look over the entire diff to spot if
any dangerous expressions were produced. I didn't see any.

There are some cases where previously the code did X*bpp/8, so the
division happened after the multiplication. Those are now just X*cpp
so the division effectively happens before the multiplication,
but that is perfectly fine since bpp is always a multiple of 8.

@@
struct drm_framebuffer *FB;
expression E;
@@
drm_helper_mode_fill_fb_struct(...) {
...
- FB->bits_per_pixel = E;
...
}

@@
struct drm_framebuffer *FB;
expression E;
@@
i9xx_get_initial_plane_config(...) {
...
- FB->bits_per_pixel = E;
...
}

@@
struct drm_framebuffer *FB;
expression E;
@@
ironlake_get_initial_plane_config(...) {
...
- FB->bits_per_pixel = E;
...
}

@@
struct drm_framebuffer *FB;
expression E;
@@
skylake_get_initial_plane_config(...) {
...
- FB->bits_per_pixel = E;
...
}

@@
struct drm_framebuffer FB;
expression E;
@@
(
- E * FB.bits_per_pixel / 8
+ E * FB.format->cpp[0]
|
- FB.bits_per_pixel / 8
+ FB.format->cpp[0]
|
- E * FB.bits_per_pixel >> 3
+ E * FB.format->cpp[0]
|
- FB.bits_per_pixel >> 3
+ FB.format->cpp[0]
|
- (FB.bits_per_pixel + 7) / 8
+ FB.format->cpp[0]
|
- FB.bits_per_pixel
+ FB.format->cpp[0] * 8
|
- FB.format->cpp[0] * 8 != 8
+ FB.format->cpp[0] != 1
)

@@
struct drm_framebuffer *FB;
expression E;
@@
(
- E * FB->bits_per_pixel / 8
+ E * FB->format->cpp[0]
|
- FB->bits_per_pixel / 8
+ FB->format->cpp[0]
|
- E * FB->bits_per_pixel >> 3
+ E * FB->format->cpp[0]
|
- FB->bits_per_pixel >> 3
+ FB->format->cpp[0]
|
- (FB->bits_per_pixel + 7) / 8
+ FB->format->cpp[0]
|
- FB->bits_per_pixel
+ FB->format->cpp[0] * 8
|
- FB->format->cpp[0] * 8 != 8
+ FB->format->cpp[0] != 1
)

@@
struct drm_plane_state *state;
expression E;
@@
(
- E * state->fb->bits_per_pixel / 8
+ E * state->fb->format->cpp[0]
|
- state->fb->bits_per_pixel / 8
+ state->fb->format->cpp[0]
|
- E * state->fb->bits_per_pixel >> 3
+ E * state->fb->format->cpp[0]
|
- state->fb->bits_per_pixel >> 3
+ state->fb->format->cpp[0]
|
- (state->fb->bits_per_pixel + 7) / 8
+ state->fb->format->cpp[0]
|
- state->fb->bits_per_pixel
+ state->fb->format->cpp[0] * 8
|
- state->fb->format->cpp[0] * 8 != 8
+ state->fb->format->cpp[0] != 1
)

@@
@@
- (8 * 8)
+ 8 * 8

@@
struct drm_framebuffer FB;
@@
- (FB.format->cpp[0])
+ FB.format->cpp[0]

@@
struct drm_framebuffer *FB;
@@
- (FB->format->cpp[0])
+ FB->format->cpp[0]

@@
@@
struct drm_framebuffer {
...
- int bits_per_pixel;
...
};

v2: Clean up the 'cpp*8 != 8' and '(8 * 8)' cases (Laurent)
v3: Adjusted the semantic patch a bit and regenerated due to code
changes

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Link: http://patchwork.freedesktop.org/patch/msgid/1481751140-18352-1-git-send-email-ville.syrjala@linux.intel.com

drm: Nuke fb->depth

Replace uses of fb->depth with fb->format->depth. Less duplicate
information is a good thing.

@@
struct drm_framebuffer *fb;
expression E;
@@
drm_helper_mode_fill_fb_struct(...) {
...
- fb->depth = E;
...
}

@@
struct nouveau_framebuffer *fb;
@@
- fb->base.depth
+ fb->base.format->depth

@@
struct drm_framebuffer fb;
@@
- fb.depth
+ fb.format->depth

@@
struct drm_framebuffer *fb;
@@
- fb->depth
+ fb->format->depth

@@
struct drm_framebuffer fb;
@@
- (fb.format->depth)
+ fb.format->depth

@@
struct drm_framebuffer *fb;
@@
- (fb->format->depth)
+ fb->format->depth

@@
@@
struct drm_framebuffer {
...
- unsigned int depth;
...
};

v2: Drop the vmw stuff (Daniel)
Rerun spatch due to code changes

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1481751095-18249-1-git-send-email-ville.syrjala@linux.intel.com

drm: Protect fb_helper list manipulation with a mutex

Though we only walk the kernel_fb_helper_list inside a panic (or single
thread debugging), we still need to protect the list manipulation on
creating/removing a framebuffer device in order to prevent list
corruption.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20161129120217.7344-3-chris@chris-wilson.co.uk

drm: Pull together probe + setup for drm_fb_helper

drm_fb_helper_probe_connector_modes() is always called before
drm_setup_crtcs(), so just move the call into drm_setup_crtcs for a
small bit of code compaction.

Note that register_framebuffer will do a modeset (when fbcon is enabled)
and hence must be moved out of the critical section. A follow-up patch
will add new locking for the fb list, hence move all the related
registration code together.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20161129120217.7344-2-chris@chris-wilson.co.uk

drm: Hold mode_config.lock to prevent hotplug whilst setting up crtcs

The fb_helper->connector_count is modified when a new connector is
constructed following a hotplug event (e.g. DP-MST). This causes trouble
for drm_setup_crtcs() and friends that assume that fb_helper is
constant:

[ 1250.872997] BUG: KASAN: slab-out-of-bounds in drm_setup_crtcs+0x320/0xf80 at addr ffff88074cdd2608
[ 1250.873020] Write of size 40 by task kworker/u8:3/480
[ 1250.873039] CPU: 2 PID: 480 Comm: kworker/u8:3 Tainted: G U 4.9.0-rc6+ #285
[ 1250.873043] Hardware name: /NUC6i3SYB, BIOS SYSKLi35.86A.0024.2015.1027.2142 10/27/2015
[ 1250.873050] Workqueue: events_unbound async_run_entry_fn
[ 1250.873056] ffff88070f9d78f0 ffffffff814b72aa ffff88074e40c5c0 ffff88074cdd2608
[ 1250.873067] ffff88070f9d7918 ffffffff8124ff3c ffff88070f9d79b0 ffff88074cdd2600
[ 1250.873079] ffff88074e40c5c0 ffff88070f9d79a0 ffffffff812501e4 0000000000000005
[ 1250.873090] Call Trace:
[ 1250.873099] [<ffffffff814b72aa>] dump_stack+0x67/0x9d
[ 1250.873106] [<ffffffff8124ff3c>] kasan_object_err+0x1c/0x70
[ 1250.873113] [<ffffffff812501e4>] kasan_report_error+0x204/0x4f0
[ 1250.873120] [<ffffffff81698df0>] ? drm_dev_printk+0x140/0x140
[ 1250.873127] [<ffffffff81250ac3>] kasan_report+0x53/0x60
[ 1250.873134] [<ffffffff81688b40>] ? drm_setup_crtcs+0x320/0xf80
[ 1250.873142] [<ffffffff8124f18e>] check_memory_region+0x13e/0x1a0
[ 1250.873147] [<ffffffff8124f5f3>] memset+0x23/0x40
[ 1250.873154] [<ffffffff81688b40>] drm_setup_crtcs+0x320/0xf80
[ 1250.873161] [<ffffffff810be7c5>] ? wake_up_q+0x45/0x80
[ 1250.873169] [<ffffffff81b0c180>] ? mutex_lock_nested+0x5a0/0x5a0
[ 1250.873176] [<ffffffff8168a0e6>] drm_fb_helper_initial_config+0x206/0x7a0
[ 1250.873183] [<ffffffff81689ee0>] ? drm_fb_helper_set_par+0x90/0x90
[ 1250.873303] [<ffffffffa0b68690>] ? intel_fbdev_fini+0x140/0x140 [i915]
[ 1250.873387] [<ffffffffa0b686b2>] intel_fbdev_initial_config+0x22/0x40 [i915]
[ 1250.873391] [<ffffffff810b50ff>] async_run_entry_fn+0x7f/0x270
[ 1250.873394] [<ffffffff810a64b0>] process_one_work+0x3d0/0x960
[ 1250.873398] [<ffffffff810a641d>] ? process_one_work+0x33d/0x960
[ 1250.873401] [<ffffffff810a60e0>] ? max_active_store+0xf0/0xf0
[ 1250.873406] [<ffffffff810f6f9d>] ? do_raw_spin_lock+0x10d/0x1a0
[ 1250.873413] [<ffffffff810a767d>] worker_thread+0x8d/0x840
[ 1250.873419] [<ffffffff810a75f0>] ? create_worker+0x2e0/0x2e0
[ 1250.873426] [<ffffffff810b0454>] kthread+0x194/0x1c0
[ 1250.873432] [<ffffffff810b02c0>] ? kthread_park+0x60/0x60
[ 1250.873438] [<ffffffff810f095d>] ? trace_hardirqs_on+0xd/0x10
[ 1250.873446] [<ffffffff810b02c0>] ? kthread_park+0x60/0x60
[ 1250.873453] [<ffffffff810b02c0>] ? kthread_park+0x60/0x60
[ 1250.873457] [<ffffffff81b12277>] ret_from_fork+0x27/0x40
[ 1250.873460] Object at ffff88074cdd2608, in cache kmalloc-32 size: 32

However, when holding the mode_config.lock around the fb_helper, we have
to be careful of any callbacks that may reenter the fb_helper and so try
to reacquire the mode_config.lock (e.g. register_framebuffer). To avoid
the mutex recursion, we have to rearrange the sequence to move the
registration into the caller outside of the mode_config.lock.

v2: drop the 1; following the lockdep assertion inside the for(;;), I
anticipated an error that doesn't happen!

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98826
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20161129120217.7344-1-chris@chris-wilson.co.uk

drm: Fix shift operations for drm_fb_helper::drm_target_preferred()

smatch correctly warns:

drivers/gpu/drm/drm_fb_helper.c:1960 drm_target_preferred() warn: should '1 << i' be a 64 bit type?
drivers/gpu/drm/drm_fb_helper.c:2001 drm_target_preferred() warn: should '1 << i' be a 64 bit type?

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/fb-helper: fix segfaults in drm_fb_helper_debug_*

A drm driver that is implementing

fb_debug_enter and fb_debug_leave

in struct fb_ops with drm fb helper functions

drm_fb_helper_debug_enter and drm_fb_helper_debug_leave

must also implement the callback 'mode_set_base_atomic' in struct
drm_crtc_helper_funcs. See Documentation/DocBook/kgdb.tmpl. The current
implementation will segfault when 'mode_set_base_atomic' is a NULL
pointer.

Before this patch at least the drm drivers armada, ast, qxl, udl and
virtio do not have a 'mode_set_base_atomic' implementation but using
drm_fb_helper_debug_(enter|leave). So these drivers may segfault when
callbacks fb_debug_(enter|leave) are called.

Avoid the issue by just checking for NULL pointers. So all drivers can
unconditionally implement fb_debug_(enter|leave) with the drm_fb_helper
functions. If callback 'mode_set_base_atomic' is not implemented, the
code in drm_fb_helper_debug_(enter|leave) does effectively nothing.

Signed-off-by: Stefan Christ <contact@stefanchrist.eu>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1479078208-25221-2-git-send-email-contact@stefanchrist.eu

drm/fb-helper: Keep references for the current set of used connectors

The fbdev helper code keeps around two lists of connectors. One is the
list of all connectors it could use, and that list already holds
references for all the connectors. However the other list, or rather
lists, is the one actively being used. That list is tracked per-crtc
and currently doesn't hold any extra references. Let's grab those
extra references to avoid oopsing when the connector vanishes. The
list of all possible connectors should get updated when the hpd happens,
but the list of actively used connectors would not get updated until
the next time the fb-helper picks through the set of possible connectors.
And so we need to hang on to the connectors until that time.

Since we need to clean up in drm_fb_helper_crtc_free() as well,
let's pull the code to a common place. And while at it let's
pull in up the modeset->mode cleanup in there as well. The case
of modeset->fb is a bit less clear. I'm thinking we should probably
hold a reference to it, but for now I just slapped on a FIXME.

v2: Cleanup things drm_fb_helper_crtc_free() too (Chris)
v3: Don't leak modeset->connectors (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Cc: Carlos Santa <carlos.santa@intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: Carlos Santa <carlos.santa@intel.com> (v1)
Tested-by: Kirill A. Shutemov <kirill@shutemov.name> (v1)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97666
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1477492878-4990-1-git-send-email-ville.syrjala@linux.intel.com

drm/fb-helper: Fix connector ref leak on error

We need to drop the connector references already taken when we
abort in the middle of drm_fb_helper_single_add_all_connectors()

Cc: stable@vger.kernel.org
Cc: Carlos Santa <carlos.santa@intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: Carlos Santa <carlos.santa@intel.com>
Tested-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1477472755-15288-2-git-send-email-ville.syrjala@linux.intel.com

drm/fb-helper: Don't call dirty callback for untouched clips

Since 4.7 kernel, we've seen the error messages like

kernel: [TTM] Buffer eviction failed
kernel: qxl 0000:00:02.0: object_init failed for (4026540032, 0x00000001)
kernel: [drm:qxl_alloc_bo_reserved [qxl]] *ERROR* failed to allocate VRAM BO

on QXL when switching and accessing on VT. The culprit was the
generic deferred_io code (qxl driver switched to it since 4.7).
There is a race between the dirty clip update and the call of
callback.

In drm_fb_helper_dirty(), the dirty clip is updated in the spinlock,
while it kicks off the update worker outside the spinlock. Meanwhile
the update worker clears the dirty clip in the spinlock, too. Thus,
when drm_fb_helper_dirty() is called concurrently, schedule_work() is
called after the clip is cleared in the first worker call.

This patch addresses it by validating the clip before calling the
dirty fb callback.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98322
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1003298
Fixes: eaa434defaca ('drm/fb-helper: Add fb_deferred_io support')
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161020150530.5787-1-tiwai@suse.de

drm: RIP mode_config->rotation_property

Now that all drivers have been converted over to the per-plane rotation
property, we can just nuke the global rotation property.

v2: Rebase due to BIT(),__builtin_ffs() & co.
Deal with superfluous code shuffling

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1477077768-4274-4-git-send-email-ville.syrjala@linux.intel.com

drm: Add support for optional per-plane rotation property

Not all planes on the system may support the same rotations/reflections,
so make it possible to create a separate property for each plane.
This way userspace gets told exactly which rotations/reflections are
possible for each plane.

v2: Add drm_plane_create_rotation_property() helper
v3: Drop the BIT(), __builtin_ffs(x) - 1,
Moar WARNs for bad parameters
Deal with superfluous code shuffling

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1474907460-10717-4-git-send-email-ville.syrjala@linux.intel.com

drm/fb-helper: reject any changes to the fbdev

The current fbdev emulation does not allow to push back changes in
width, height or depth to KMS, hence reject any changes with an
error. This makes sure that fbdev ioctl's fail properly and user
space does not assume that changes succeeded.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161011231504.17688-1-stefan@agner.ch

drm: Add reference counting to drm_atomic_state

drm_atomic_state has a complicated single owner model that tracks the
single reference from allocation through to destruction on another
thread - or perhaps on a local error path. We can simplify this tracking
by using reference counting (at a cost of a few more atomics). This is
even more beneficial when the lifetime of the state becomes more
convoluted than being passed to a single worker thread for the commit.

v2: Double check !intel atomic_commit functions for missing gets
v3: Update kerneldocs

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161014121833.439-27-chris@chris-wilson.co.uk

drm/fb-helper: Fix sparse warnings

drm/drm_fb_helper.c:2306:12: warning: symbol 'drm_fb_helper_modinit' was not declared. Should it be static?

While at it, move the lefover static inline to the right place.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1474292035-15695-4-git-send-email-ville.syrjala@linux.intel.com

drm/fb-helper: Make docs for fb_set_suspend wrappers consistent

I figured I might as well go ocd and make them booleans and rename the
locked version too.

v2: Review from Noralf.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Fixes: cfe63423d9be ("drm/fb-helper: Add drm_fb_helper_set_suspend_unlocked()")
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160823152727.31788-1-daniel.vetter@ffwll.ch

drm/fb-helper: Add drm_fb_helper_set_suspend_unlocked()

This adds a function that also takes the console lock before calling
fb_set_suspend() in contrast to drm_fb_helper_set_suspend() which is
a plain wrapper around fb_set_suspend().
Resume is run asynchronously using a worker if the console lock is
already taken. This is modelled after the i915 driver.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1471953246-29602-1-git-send-email-noralf@tronnes.org