drm/tidss: Use DRM_PLANE_COMMIT_ACTIVE_ONLY

At the moment the driver does not use DRM_PLANE_COMMIT_ACTIVE_ONLY, but
still checks for crtc->state->active in tidss_crtc_atomic_flush(), and
skips the flush if the crtc is not active.

The exact reason why DRM_PLANE_COMMIT_ACTIVE_ONLY is not used has been
lost in history. DRM_PLANE_COMMIT_ACTIVE_ONLY does also affect the plane
updates, and I think the issue was related to multi-display systems and
moving planes between the displays. However, it is possible the issue
was only present on the older DSS hardware, handled by the omapdrm
driver (on which the tidss driver is loosely based).

Reviewing the code related to DRM_PLANE_COMMIT_ACTIVE_ONLY does not show
any issues, and testing on J7 EVM with two displays works fine.

Change the driver to use DRM_PLANE_COMMIT_ACTIVE_ONLY.

Reviewed-by: Aradhya Bhatia <a-bhatia1@ti.com>
Link: https://lore.kernel.org/r/20231109-tidss-probe-v2-11-ac91b5ea35c0@ideasonboard.com
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

Revert "drm/tidss: Annotate dma-fence critical section in commit path"

This reverts commit 4d56a4f08391857ba93465de489707b66adad114.

The DMA-fence annotations cause a lockdep warning (see below). As per
https://patchwork.freedesktop.org/patch/462170/ it sounds like the
annotations don't work correctly.

======================================================
WARNING: possible circular locking dependency detected
6.6.0-rc2+ #1 Not tainted
------------------------------------------------------
kmstest/733 is trying to acquire lock:
ffff8000819377f0 (fs_reclaim){+.+.}-{0:0}, at: __kmem_cache_alloc_node+0x58/0x2d4

but task is already holding lock:
ffff800081a06aa0 (dma_fence_map){++++}-{0:0}, at: tidss_atomic_commit_tail+0x20/0xc0 [tidss]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (dma_fence_map){++++}-{0:0}:
__dma_fence_might_wait+0x5c/0xd0
dma_resv_lockdep+0x1a4/0x32c
do_one_initcall+0x84/0x2fc
kernel_init_freeable+0x28c/0x4c4
kernel_init+0x24/0x1dc
ret_from_fork+0x10/0x20

-> #1 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
fs_reclaim_acquire+0x70/0xe4
__kmem_cache_alloc_node+0x58/0x2d4
kmalloc_trace+0x38/0x78
__kthread_create_worker+0x3c/0x150
kthread_create_worker+0x64/0x8c
workqueue_init+0x1e8/0x2f0
kernel_init_freeable+0x11c/0x4c4
kernel_init+0x24/0x1dc
ret_from_fork+0x10/0x20

-> #0 (fs_reclaim){+.+.}-{0:0}:
__lock_acquire+0x1370/0x20d8
lock_acquire+0x1e8/0x308
fs_reclaim_acquire+0xd0/0xe4
__kmem_cache_alloc_node+0x58/0x2d4
__kmalloc_node_track_caller+0x58/0xf0
kmemdup+0x34/0x60
regmap_bulk_write+0x64/0x2c0
tc358768_bridge_pre_enable+0x8c/0x12d0 [tc358768]
drm_atomic_bridge_call_pre_enable+0x68/0x80 [drm]
drm_atomic_bridge_chain_pre_enable+0x50/0x158 [drm]
drm_atomic_helper_commit_modeset_enables+0x164/0x264 [drm_kms_helper]
tidss_atomic_commit_tail+0x58/0xc0 [tidss]
commit_tail+0xa0/0x188 [drm_kms_helper]
drm_atomic_helper_commit+0x1a8/0x1c0 [drm_kms_helper]
drm_atomic_commit+0xa8/0xe0 [drm]
drm_mode_atomic_ioctl+0x9ec/0xc80 [drm]
drm_ioctl_kernel+0xc4/0x170 [drm]
drm_ioctl+0x234/0x4b0 [drm]
drm_compat_ioctl+0x110/0x12c [drm]
__arm64_compat_sys_ioctl+0x128/0x150
invoke_syscall+0x48/0x110
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc_compat+0x1c/0x38
el0_svc_compat+0x48/0xb4
el0t_32_sync_handler+0xb0/0x138
el0t_32_sync+0x194/0x198

other info that might help us debug this:

Chain exists of:
fs_reclaim --> mmu_notifier_invalidate_range_start --> dma_fence_map

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
rlock(dma_fence_map);
lock(mmu_notifier_invalidate_range_start);
lock(dma_fence_map);
lock(fs_reclaim);

*** DEADLOCK ***

3 locks held by kmstest/733:
#0: ffff800082e5bba0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_mode_atomic_ioctl+0x118/0xc80 [drm]
#1: ffff000004224c88 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0xdc/0x1a0 [drm]
#2: ffff800081a06aa0 (dma_fence_map){++++}-{0:0}, at: tidss_atomic_commit_tail+0x20/0xc0 [tidss]

stack backtrace:
CPU: 0 PID: 733 Comm: kmstest Not tainted 6.6.0-rc2+ #1
Hardware name: Toradex Verdin AM62 on Verdin Development Board (DT)
Call trace:
dump_backtrace+0x98/0x118
show_stack+0x18/0x24
dump_stack_lvl+0x60/0xac
dump_stack+0x18/0x24
print_circular_bug+0x288/0x368
check_noncircular+0x168/0x17c
__lock_acquire+0x1370/0x20d8
lock_acquire+0x1e8/0x308
fs_reclaim_acquire+0xd0/0xe4
__kmem_cache_alloc_node+0x58/0x2d4
__kmalloc_node_track_caller+0x58/0xf0
kmemdup+0x34/0x60
regmap_bulk_write+0x64/0x2c0
tc358768_bridge_pre_enable+0x8c/0x12d0 [tc358768]
drm_atomic_bridge_call_pre_enable+0x68/0x80 [drm]
drm_atomic_bridge_chain_pre_enable+0x50/0x158 [drm]
drm_atomic_helper_commit_modeset_enables+0x164/0x264 [drm_kms_helper]
tidss_atomic_commit_tail+0x58/0xc0 [tidss]
commit_tail+0xa0/0x188 [drm_kms_helper]
drm_atomic_helper_commit+0x1a8/0x1c0 [drm_kms_helper]
drm_atomic_commit+0xa8/0xe0 [drm]
drm_mode_atomic_ioctl+0x9ec/0xc80 [drm]
drm_ioctl_kernel+0xc4/0x170 [drm]
drm_ioctl+0x234/0x4b0 [drm]
drm_compat_ioctl+0x110/0x12c [drm]
__arm64_compat_sys_ioctl+0x128/0x150
invoke_syscall+0x48/0x110
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc_compat+0x1c/0x38
el0_svc_compat+0x48/0xb4
el0t_32_sync_handler+0xb0/0x138
el0t_32_sync+0x194/0x198

Fixes: 4d56a4f08391 ("drm/tidss: Annotate dma-fence critical section in commit path")
Reviewed-by: Aradhya Bhatia <a-bhatia1@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230920-dma-fence-annotation-revert-v1-1-7ebf6f7f5bf6@ideasonboard.com

drm/tidss: Update encoder/bridge chain connect model

With the new encoder/bridge chain model, the display controller driver
is required to create a drm_connector entity instead of asking the
bridge to do so during drm_bridge_attach. Moreover, the controller
driver should create a drm_bridge entity to negotiate bus formats and a
'simple' drm_encoder entity to expose it to userspace.

Update the encoder/bridge initialization sequence in tidss as per the
new model.

Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230606082142.23760-8-a-bhatia1@ti.com

drm/tidss: Remove unnecessary include statements for drm_crtc_helper.h

Several source files include drm_crtc_helper.h without needing it or
only to get its transitive include statements; leading to unnecessary
compile-time dependencies.

Directly include required headers and drop drm_crtc_helper.h where
possible.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230116131235.18917-20-tzimmermann@suse.de

drm/fb-helper: Remove unnecessary include statements

Remove include statements for <drm/drm_fb_helper.h> where it is not
required (i.e., most of them). In a few places include other header
files that are required by the source code.

v3:
* fix amdgpu include statements
* fix rockchip include statements

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-23-tzimmermann@suse.de

drm/tidss: fix repeated words in comments

Delete the redundant word 'to'.

Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220824130450.41703-1-yuanjilin@cdjrlc.com

drm/fb: remove unused includes of drm_fb_cma_helper.h

Quite a lot of drivers include the drm_fb_cma_helper.h header file
without actually making use of it's provided API, hence remove those
includes.

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-2-dakr@redhat.com

drm/bridge: Centralize error message when bridge attach fails

Being informed of a failure to attach a bridge is useful, and many
drivers prints an error message in that case. Move the message to
drm_bridge_attach() to avoid code duplication.

Suggested-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Jyri Sarha <jyri.sarha@iki.fi>

drm/tidss: Annotate dma-fence critical section in commit path

Ends right after hw_done(), totally standard case.

Acked-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210121152959.1725404-12-daniel.vetter@ffwll.ch

drm/tidss: fix modeset init for DPI panels

The connector type for DISPC's DPI videoport was set the LVDS instead of
DPI. This causes any DPI panel setup to fail with tidss, making all DPI
panels unusable.

Fix this by using correct connector type.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Fixes: 32a1795f57eecc39749017 ("drm/tidss: New driver for TI Keystone platform Display SubSystem")
Cc: stable@vger.kernel.org # v5.7+
Link: https://patchwork.freedesktop.org/patch/msgid/20200604080214.107159-1-tomi.valkeinen@ti.com
Reviewed-by: Jyri Sarha <jsarha@ti.com>

drm/tidss: Replace HTTP links with HTTPS ones

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200713123913.34205-1-grandmaster@al2klimov.de

drm/atomic-helper: reset vblank on crtc reset

Only when vblanks are supported ofc.

Some drivers do this already, but most unfortunately missed it. This
opens up bugs after driver load, before the crtc is enabled for the
first time. syzbot spotted this when loading vkms as a secondary
output. Given how many drivers are buggy it's best to solve this once
and for all in shared helper code.

Aside from moving the few existing calls to drm_crtc_vblank_reset into
helpers (i915 doesn't use helpers, so keeps its own) I think the
regression risk is minimal: atomic helpers already rely on drivers
calling drm_crtc_vblank_on/off correctly in their hooks when they
support vblanks. And driver that's failing to handle vblanks after
this is missing those calls already, and vblanks could only work by
accident when enabling a CRTC for the first time right after boot.

Big thanks to Tetsuo for helping track down what's going wrong here.

There's only a few drivers which already had the necessary call and
needed some updating:
- komeda, atmel and tidss also needed to be changed to call
__drm_atomic_helper_crtc_reset() intead of open coding it
- tegra and msm even had it in the same place already, just code
motion, and malidp already uses __drm_atomic_helper_crtc_reset().
- Laurent noticed that rcar-du and omap open-code their crtc reset and
hence would actually be broken by this patch now. So fix them up by
reusing the helpers, which brings the drm_crtc_vblank_reset() back.

Only call left is in i915, which doesn't use drm_mode_config_reset,
but has its own fastboot infrastructure. So that's the only case where
we actually want this in the driver still.

I've also reviewed all other drivers which set up vblank support with
drm_vblank_init. After the previous patch fixing mxsfb all atomic
drivers do call drm_crtc_vblank_on/off as they should, the remaining
drivers are either legacy kms or legacy dri1 drivers, so not affected
by this change to atomic helpers.

v2: Use the drm_dev_has_vblank() helper.

v3: Laurent pointed out that omap and rcar-du used drm_crtc_vblank_off
instead of drm_crtc_vblank_reset. Adjust them too.

v4: Laurent noticed that rcar-du and omap open-code their crtc reset
and hence would actually be broken by this patch now. So fix them up
by reusing the helpers, which brings the drm_crtc_vblank_reset() back.

v5: also mention rcar-du and ompadrm in the proper commit message
above (Laurent).

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://syzkaller.appspot.com/bug?id=0ba17d70d062b2595e1f061231474800f076c7cb
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot+0871b14ca2e2fb64f6e3@syzkaller.appspotmail.com
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: "James (Qian) Wang" <james.qian.wang@arm.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Mihail Atanassov <mihail.atanassov@arm.com>
Cc: Brian Starkey <brian.starkey@arm.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.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>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Brian Masney <masneyb@onstation.org>
Cc: Emil Velikov <emil.velikov@collabora.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-tegra@vger.kernel.org
Cc: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612160056.2082681-1-daniel.vetter@ffwll.ch

drm/tidss: Don't use drm_device->dev_private

Upcasting using a container_of macro is more typesafe, faster and
easier for the compiler to optimize.

Tested-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200415074034.175360-25-daniel.vetter@ffwll.ch

drm/tidss: Drop explicit drm_mode_config_cleanup call

It's right above the drm_dev_put().

This is made possible by a preceeding patch which added a drmm_
cleanup action to drm_mode_config_init(), hence all we need to do to
ensure that drm_mode_config_cleanup() is run on final drm_device
cleanup is check the new error code for _init().

Aside: Another driver with a bit much devm_kzalloc, which should
probably use drmm_kzalloc instead ...

I'm pretty sure this one blows up already under KASAN because it's
using devm_drm_dev_init, and later on devm_kzalloc. Hence the memory
will get freed before the final drm_dev_put (all from the devres
code), but the cleanup in that final drm_dev_put will access the just
freed memory.

Unfortunately fixing this properly needs slightly more work, namely
drmm_ versions for all the drm objects (planes, crtc, ...), so that
the cleanup actually happens before even drmm_kzalloc would release
the underlying memory. Not quite there yet.

v2: Explain why this cleanup is possible (Laurent).

v3: Use drmm_mode_config_init() for more clarity (Sam, Thomas)

Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Jyri Sarha <jsarha@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-42-daniel.vetter@ffwll.ch

drm/tidss: dispc: Fix broken plane positioning code

The old implementation of placing planes on the CRTC while configuring
the planes was naive and relied on the order in which the planes were
configured, enabled, and disabled. The situation where a plane's zpos
was changed on the fly was completely broken. The usual symptoms of
this problem was scrambled display and a flood of sync lost errors,
when a plane was active in two layers at the same time, or a missing
plane, in case when a layer was accidentally disabled.

The rewrite takes a more straight forward approach when HW is
concerned. The plane positioning registers are in the CRTC (or
actually OVR) register space and it is more natural to configure them
in a one go when configuring the CRTC. To do this we need make sure we
have all the planes on the updated CRTCs in the new atomic state. The
untouched planes on CRTCs that need plane position update are added to
the atomic state in tidss_atomic_check().

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200227120052.23168-1-jsarha@ti.com

drm/bridge: Extend bridge API to disable connector creation

Most bridge drivers create a DRM connector to model the connector at the
output of the bridge. This model is historical and has worked pretty
well so far, but causes several issues:

- It prevents supporting more complex display pipelines where DRM
connector operations are split over multiple components. For instance a
pipeline with a bridge connected to the DDC signals to read EDID data,
and another one connected to the HPD signal to detect connection and
disconnection, will not be possible to support through this model.

- It requires every bridge driver to implement similar connector
handling code, resulting in code duplication.

- It assumes that a bridge will either be wired to a connector or to
another bridge, but doesn't support bridges that can be used in both
positions very well (although there is some ad-hoc support for this in
the analogix_dp bridge driver).

In order to solve these issues, ownership of the connector should be
moved to the display controller driver (where it can be implemented
using helpers provided by the core).

Extend the bridge API to allow disabling connector creation in bridge
drivers as a first step towards the new model. The new flags argument to
the bridge .attach() operation allows instructing the bridge driver to
skip creating a connector. Unconditionally set the new flags argument to
0 for now to keep the existing behaviour, and modify all existing bridge
drivers to return an error when connector creation is not requested as
they don't support this feature yet.

The change is based on the following semantic patch, with manual review
and edits.

@ rule1 @
identifier funcs;
identifier fn;
@@
struct drm_bridge_funcs funcs = {
...,
.attach = fn
};

@ depends on rule1 @
identifier rule1.fn;
identifier bridge;
statement S, S1;
@@
int fn(
struct drm_bridge *bridge
+ , enum drm_bridge_attach_flags flags
)
{
... when != S
+ if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
+ DRM_ERROR("Fix bridge driver to make connector optional!");
+ return -EINVAL;
+ }
+
S1
...
}

@ depends on rule1 @
identifier rule1.fn;
identifier bridge, flags;
expression E1, E2, E3;
@@
int fn(
struct drm_bridge *bridge,
enum drm_bridge_attach_flags flags
) {
<...
drm_bridge_attach(E1, E2, E3
+ , flags
)
...>
}

@@
expression E1, E2, E3;
@@
drm_bridge_attach(E1, E2, E3
+ , 0
)

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-10-laurent.pinchart@ideasonboard.com

drm/tidss: New driver for TI Keystone platform Display SubSystem

This patch adds a new DRM driver for Texas Instruments DSS IPs used on
Texas Instruments Keystone K2G, AM65x, and J721e SoCs. The new DSS IP is
a major change to the older DSS IP versions, which are supported by
the omapdrm driver. While on higher level the Keystone DSS resembles
the older DSS versions, the registers are completely different and the
internal pipelines differ a lot.

DSS IP found on K2G is an "ultra-light" version, and has only a single
plane and a single output. The K3 DSS IPs are found on AM65x and J721E
SoCs. AM65x DSS has two video ports, one full video plane, and another
"lite" plane without scaling support. J721E has 4 video ports, 2 video
planes and 2 lite planes. AM65x DSS has also an integrated OLDI (LVDS)
output.

Version history:

v2: - rebased on top of drm-next-2019-11-27
- sort all include lines in all files
- remove all include <drm/drmP.h>
- remove select "select VIDEOMODE_HELPERS"
- call dispc_vp_setup() later in tidss_crtc_atomic_flush() (there is no
to call it in new modeset case as it is also called in vp_enable())
- change probe sequence and drm_device allocation (follow example in
drm_drv.c)
- use __maybe_unused instead of #ifdef for pm functions
- remove "struct drm_fbdev_cma *fbdev;" from driver data
- check panel connector type before connecting it

v3: no change

v4: no change

v5: - remove fifo underflow irq handling, it is not an error and
it should be used for debug purposes only
- memory tuning, prefetch plane fifo up to high-threshold value to
minimize possibility of underflows.

v6: - Check CTM and gamma support from dispc_features when creating crtc
- Implement CTM support for k2g and fix k3 CTM implementation
- Remove gamma property persistence and always write color properties
in a new modeset

v7: - Fix checkpatch.pl --strict issues
- Rebase on top of drm-misc-next-2020-01-10

v8: - Remove idle debug prints from dispc_init()
- Add Reviewed-by: Benoit Parrot <bparrot@ti.com>

v9: - Rename dispc_write_irqenable() to dispc_set_irqenable() to avoid
conflict exported omapfb function with same name
- Add Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

Co-developed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/925fbfad58ff828e8e07fdff7073a0ee65750c3d.1580129724.git.jsarha@ti.com