fbdev: Align deferred I/O with naming of helpers

Deferred-I/O generator macros generate callbacks for struct fb_ops
that operate on memory ranges in I/O address space or system address
space. Rename the macros to use the _IOMEM_ and _SYSMEM_ infixes of
their underlying helpers. Adapt all users. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230729193157.15446-5-tzimmermann@suse.de

drm: Remove flag FBINFO_DEFAULT from fbdev emulation

The flag FBINFO_DEFAULT is 0 and has no effect, as struct fbinfo.flags
has been allocated to zero by framebuffer_alloc(). So do not set it.

Flags should signal differences from the default values. After cleaning
up all occurrences of FBINFO_DEFAULT, the token will be removed.

v2:
* fix commit message (Miguel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230715185343.7193-2-tzimmermann@suse.de

drm/client: Send hotplug event after registering a client

Generate a hotplug event after registering a client to allow the
client to configure its display. Remove the hotplug calls from the
existing clients for fbdev emulation. This change fixes a concurrency
bug between registering a client and receiving events from the DRM
core. The bug is present in the fbdev emulation of all drivers.

The fbdev emulation currently generates a hotplug event before
registering the client to the device. For each new output, the DRM
core sends an additional hotplug event to each registered client.

If the DRM core detects first output between sending the artificial
hotplug and registering the device, the output's hotplug event gets
lost. If this is the first output, the fbdev console display remains
dark. This has been observed with amdgpu and fbdev-generic.

Fix this by adding hotplug generation directly to the client's
register helper drm_client_register(). Registering the client and
receiving events are serialized by struct drm_device.clientlist_mutex.
So an output is either configured by the initial hotplug event, or
the client has already been registered.

The bug was originally added in commit 6e3f17ee73f7 ("drm/fb-helper:
generic: Call drm_client_add() after setup is done"), in which adding
a client and receiving a hotplug event switched order. It was hidden,
as most hardware and drivers have at least on static output configured.
Other drivers didn't use the internal DRM client or still had struct
drm_mode_config_funcs.output_poll_changed set. That callback handled
hotplug events as well. After not setting the callback in amdgpu in
commit 0e3172bac3f4 ("drm/amdgpu: Don't set struct
drm_driver.output_poll_changed"), amdgpu did not show a framebuffer
console if output events got lost. The bug got copy-pasted from
fbdev-generic into the other fbdev emulation.

Reported-by: Moritz Duge <MoritzDuge@kolahilft.de>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/2649
Fixes: 6e3f17ee73f7 ("drm/fb-helper: generic: Call drm_client_add() after setup is done")
Fixes: 8ab59da26bc0 ("drm/fb-helper: Move generic fbdev emulation into separate source file")
Fixes: b79fe9abd58b ("drm/fbdev-dma: Implement fbdev emulation for GEM DMA helpers")
Fixes: 63c381552f69 ("drm/armada: Implement fbdev emulation as in-kernel client")
Fixes: 49953b70e7d3 ("drm/exynos: Implement fbdev emulation as in-kernel client")
Fixes: 8f1aaccb04b7 ("drm/gma500: Implement client-based fbdev emulation")
Fixes: 940b869c2f2f ("drm/msm: Implement fbdev emulation as in-kernel client")
Fixes: 9e69bcd88e45 ("drm/omapdrm: Implement fbdev emulation as in-kernel client")
Fixes: e317a69fe891 ("drm/radeon: Implement client-based fbdev emulation")
Fixes: 71ec16f45ef8 ("drm/tegra: Implement fbdev emulation as in-kernel client")
Fixes: 0e3172bac3f4 ("drm/amdgpu: Don't set struct drm_driver.output_poll_changed")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Moritz Duge <MoritzDuge@kolahilft.de>
Tested-by: Torsten Krah <krah.tm@gmail.com>
Tested-by: Paul Schyska <pschyska@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Mikko Perttunen <mperttunen@nvidia.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: amd-gfx@lists.freedesktop.org
Cc: linux-tegra@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> # msm
Link: https://patchwork.freedesktop.org/patch/msgid/20230710091029.27503-1-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/fbdev-generic: Rename symbols

Rename symbols to match the style of other fbdev-emulation source
code. No functional changes.

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/20230320150751.20399-9-tzimmermann@suse.de

drm/fbdev-generic: Clean up after failed probing

Clean up fbdev and client state if the probe function fails. It
used to leak allocated resources. Also reorder the individual steps
to simplify cleanup.

v2:
* move screen_size update into separate patches

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/20230320150751.20399-7-tzimmermann@suse.de

drm/fbdev-generic: Set screen size to size of GEM buffer

The size of the screen memory should be equivalent to the size of
the screen's GEM buffer. Don't recalculate the value.

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/20230320150751.20399-6-tzimmermann@suse.de

drm/fbdev-generic: Always use shadow buffering

Remove all codepaths that implement fbdev output directly on GEM
buffers. Always allocate a shadow buffer in system memory and set
up deferred I/O for mmap.

The fbdev code that operated directly on GEM buffers was used by
drivers based on GEM DMA helpers. Those drivers have been migrated
to use fbdev-dma, a dedicated fbdev emulation for DMA memory. All
remaining users of fbdev-generic require shadow buffering.

Memory management of the remaining callers uses TTM, GEM SHMEM
helpers or a variant of GEM DMA helpers that is incompatible with
fbdev-dma. Therefore remove the unused codepaths from fbdev-generic
and simplify the code.

Using a shadow buffer with deferred I/O is probably the best case
for most remaining callers. Some of the TTM-based drivers might
benefit from a dedicated fbdev emulation that operates directly on
the driver's video memory.

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/20230320150751.20399-2-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/fbdev-generic: Rename struct fb_info 'fbi' to 'info'

The generic fbdev emulation names variables of type struct fb_info
both 'fbi' and 'info'. The latter seems to be more common in fbdev
code, so name fbi accordingly.

Also replace the duplicate variable in drm_fbdev_fb_destroy().

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-11-tzimmermann@suse.de

drm/fbdev-generic: Inline clean-up helpers into drm_fbdev_fb_destroy()

The fbdev framebuffer cleanup in drm_fbdev_fb_destroy() calls
drm_fbdev_release() and drm_fbdev_cleanup(). Inline both into the
caller. 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/20230125200415.14123-10-tzimmermann@suse.de

drm/fbdev-generic: Minimize client unregistering

For uninitialized framebuffers, only release the DRM client and
free the fbdev memory. Do not attempt to clean up the framebuffer.

DRM fbdev clients have a two-step initialization: first create
the DRM client; then create the framebuffer device on the first
successful hotplug event. In cases where the client never creates
the framebuffer, only the client state needs to be released. We
can detect which case it is, full or client-only cleanup, by
looking at the presence of fb_helper's info field.

v3:
* fix typo in commit message (Javier)
* release client before unpreparing fbdev
v2:
* remove test for (fbi != NULL) in drm_fbdev_cleanup() (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-9-tzimmermann@suse.de

drm/fbdev-generic: Minimize hotplug error handling

Call drm_fb_helper_fini() in the generic-fbdev hotplug helper
to revert the effects of drm_fb_helper_init(). No full cleanup
is required.

v3:
* fix error in commit message (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-8-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/fbdev-generic: Initialize fb-helper structure in generic setup

Initialize the fb-helper structure immediately after its allocation
in drm_fbdev_generic_setup(). That will make it easier to fill it with
driver-specific values, such as the preferred BPP.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-5-tzimmermann@suse.de

drm/client: Add hotplug_failed flag

Signal failed hotplugging with a flag in struct drm_client_dev. If set,
the client helpers will not further try to set up the fbdev display.

This used to be signalled with a combination of cleared pointers in
struct drm_fb_helper, which prevents us from initializing these pointers
early after allocation.

The change also harmonizes behavior among DRM clients. Additional DRM
clients will now handle failed hotplugging like fbdev does.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-3-tzimmermann@suse.de

drm/client: Test for connectors before sending hotplug event

Test for connectors in the client code and remove a similar test
from the generic fbdev emulation. Do nothing if the test fails.
Not having connectors indicates a driver bug.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-2-tzimmermann@suse.de

drm/fb-helper: Don't use the preferred depth for the BPP default

If no preferred value for bits-per-pixel has been given, fall back
to 32. Never use the preferred depth. The color depth is the number
of color/alpha bits per pixel, while bpp is the overall number of
bits in most cases.

Most noteworthy, XRGB8888 has a depth of 24 and a bpp value of 32.
Using depth for bpp would make the value 24 as well and format
selection in fbdev helpers fails. Unfortunately XRGB8888 is the most
common format and the old heuristic therefore fails for most of
the drivers (unless they implement the 24-bit RGB888 format).

Picking a bpp of 32 will later on result in a default depth of 24
and the format XRGB8888. As XRGB8888 is the default format for most
of the current and legacy graphics stack, all drivers must support
it. So it is the safe choice.

v2:
* fix commit-message typo (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123115348.2521-8-tzimmermann@suse.de

drm/fb-helper: Use a per-driver FB deferred I/O handler

The DRM fbdev emulation layer sets the struct fb_info .fbdefio field to
a struct fb_deferred_io pointer, that is shared across all drivers that
use the generic drm_fbdev_generic_setup() helper function.

It is a problem because the fbdev core deferred I/O logic assumes that
the struct fb_deferred_io data is not shared between devices, and it's
stored there state such as the list of pages touched and a mutex that
is use to synchronize between the fb_deferred_io_track_page() function
that track the dirty pages and fb_deferred_io_work() workqueue handler
doing the actual deferred I/O.

The latter can lead to the following error, since it may happen that two
drivers are probed and then one is removed, which causes the mutex bo be
destroyed and not existing anymore by the time the other driver tries to
grab it for the fbdev deferred I/O logic:

[ 369.756553] ------------[ cut here ]------------
[ 369.756604] DEBUG_LOCKS_WARN_ON(lock->magic != lock)
[ 369.756631] WARNING: CPU: 2 PID: 1023 at kernel/locking/mutex.c:582 __mutex_lock+0x348/0x424
[ 369.756744] Modules linked in: nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ip
v6 nf_defrag_ipv4 ip_set nf_tables nfnetlink qrtr btsdio bluetooth sunrpc brcmfmac snd_soc_hdmi_codec cpufreq_dt cfg80211 vfat fat vc4 rfkill brcmutil raspberrypi_cpufreq i2c_bcm2835 iproc_rng200 bcm2711_thermal snd_soc_core snd_pcm_dmaen
gine leds_gpio nvmem_rmem joydev hid_cherry uas usb_storage gpio_raspberrypi_exp v3d snd_pcm raspberrypi_hwmon gpu_sched bcm2835_wdt broadcom bcm_phy_lib snd_timer genet snd mdio_bcm_unimac clk_bcm2711_dvp soundcore drm_display_helper pci
e_brcmstb cec ip6_tables ip_tables fuse
[ 369.757400] CPU: 2 PID: 1023 Comm: fbtest Not tainted 5.19.0-rc6+ #94
[ 369.757455] Hardware name: raspberrypi,4-model-b Raspberry Pi 4 Model B Rev 1.4/Raspberry Pi 4 Model B Rev 1.4, BIOS 2022.10 10/01/2022
[ 369.757538] pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 369.757596] pc : __mutex_lock+0x348/0x424
[ 369.757635] lr : __mutex_lock+0x348/0x424
[ 369.757672] sp : ffff80000953bb00
[ 369.757703] x29: ffff80000953bb00 x28: ffff17fdc087c000 x27: 0000000000000002
[ 369.757771] x26: ffff17fdc349f9b0 x25: fffffc5ff72e0100 x24: 0000000000000000
[ 369.757838] x23: 0000000000000000 x22: 0000000000000002 x21: ffffa618df636f10
[ 369.757903] x20: ffff80000953bb68 x19: ffffa618e0f18138 x18: 0000000000000001
[ 369.757968] x17: 0000000020000000 x16: 0000000000000002 x15: 0000000000000000
[ 369.758032] x14: 0000000000000000 x13: 284e4f5f4e524157 x12: 5f534b434f4c5f47
[ 369.758097] x11: 00000000ffffdfff x10: ffffa618e0c79f88 x9 : ffffa618de472484
[ 369.758162] x8 : 000000000002ffe8 x7 : c0000000ffffdfff x6 : 00000000000affa8
[ 369.758227] x5 : 0000000000001fff x4 : 0000000000000000 x3 : 0000000000000027
[ 369.758292] x2 : 0000000000000001 x1 : ffff17fdc087c000 x0 : 0000000000000028
[ 369.758357] Call trace:
[ 369.758383] __mutex_lock+0x348/0x424
[ 369.758420] mutex_lock_nested+0x4c/0x5c
[ 369.758459] fb_deferred_io_mkwrite+0x78/0x1d8
[ 369.758507] do_page_mkwrite+0x5c/0x19c
[ 369.758550] wp_page_shared+0x70/0x1a0
[ 369.758590] do_wp_page+0x3d0/0x510
[ 369.758628] handle_pte_fault+0x1c0/0x1e0
[ 369.758670] __handle_mm_fault+0x250/0x380
[ 369.758712] handle_mm_fault+0x17c/0x3a4
[ 369.758753] do_page_fault+0x158/0x530
[ 369.758792] do_mem_abort+0x50/0xa0
[ 369.758831] el0_da+0x78/0x19c
[ 369.758864] el0t_64_sync_handler+0xbc/0x150
[ 369.758904] el0t_64_sync+0x190/0x194
[ 369.758942] irq event stamp: 11395
[ 369.758973] hardirqs last enabled at (11395): [<ffffa618de472554>] __up_console_sem+0x74/0x80
[ 369.759042] hardirqs last disabled at (11394): [<ffffa618de47254c>] __up_console_sem+0x6c/0x80
[ 369.760554] softirqs last enabled at (11392): [<ffffa618de330a74>] __do_softirq+0x4c4/0x6b8
[ 369.762060] softirqs last disabled at (11383): [<ffffa618de3c9124>] __irq_exit_rcu+0x104/0x214
[ 369.763564] ---[ end trace 0000000000000000 ]---

Fixes: d536540f304c ("drm/fb-helper: Add generic fbdev emulation .fb_probe function")
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230121192418.2814955-4-javierm@redhat.com

drm/fb-helper: Check fb_deferred_io_init() return value

The fb_deferred_io_init() can fail and return an errno code but currently
there is no check for its return value.

Fix that and propagate to errno to the caller in the case of a failure.

Fixes: d536540f304c ("drm/fb-helper: Add generic fbdev emulation .fb_probe function")
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230121192418.2814955-3-javierm@redhat.com

drm/fbdev: Include <linux/vmalloc.h>

Include <linux/vmalloc.h> in fbdev emulation to get vzalloc() and
vfree() on MIPS. The error messages are shown below and bug reports
are at [1] and [2].

drivers/gpu/drm/drm_fbdev_generic.c: In function 'drm_fbdev_cleanup':
drivers/gpu/drm/drm_fbdev_generic.c:63:17: error: implicit declaration of function 'vfree'; did you mean 'kvfree'? [-Werror=implicit-function-declaration]
63 | vfree(shadow);
| ^~~~~
| kvfree
drivers/gpu/drm/drm_fbdev_generic.c: In function 'drm_fbdev_fb_probe':
drivers/gpu/drm/drm_fbdev_generic.c:219:38: error: implicit declaration of function 'vzalloc'; did you mean 'kvzalloc'? [-Werror=implicit-function-declaration]
219 | fbi->screen_buffer = vzalloc(fbi->screen_size);
| ^~~~~~~
| kvzalloc
drivers/gpu/drm/drm_fbdev_generic.c:219:36: warning: assignment to 'char *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
219 | fbi->screen_buffer = vzalloc(fbi->screen_size);

Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 8ab59da26bc0 ("drm/fb-helper: Move generic fbdev emulation into separate source file")
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
Link: https://lore.kernel.org/dri-devel/202211060911.5U76gMtE-lkp@intel.com/T/#u # [1]
Link: https://lore.kernel.org/dri-devel/202211060331.1SoD1tAR-lkp@intel.com/T/#u # [2]
Link: https://patchwork.freedesktop.org/patch/msgid/20221107125329.12842-2-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