linux.git/drivers/gpu/drm/exynos, branch v6.5

drm/client: Send hotplug event after registering a client

2023-07-11T12:02:01+00:00

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 
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 
Tested-by: Moritz Duge 
Tested-by: Torsten Krah 
Tested-by: Paul Schyska 
Cc: Daniel Vetter 
Cc: David Airlie 
Cc: Noralf Trønnes 
Cc: Maarten Lankhorst 
Cc: Maxime Ripard 
Cc: Javier Martinez Canillas 
Cc: Russell King 
Cc: Inki Dae 
Cc: Seung-Woo Kim 
Cc: Kyungmin Park 
Cc: Krzysztof Kozlowski 
Cc: Patrik Jakobsson 
Cc: Rob Clark 
Cc: Abhinav Kumar 
Cc: Dmitry Baryshkov 
Cc: Tomi Valkeinen 
Cc: Alex Deucher 
Cc: "Christian König" 
Cc: "Pan, Xinhui" 
Cc: Thierry Reding 
Cc: Mikko Perttunen 
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:  # v5.2+
Reviewed-by: Javier Martinez Canillas 
Reviewed-by: Dmitry Baryshkov  # msm
Link: https://patchwork.freedesktop.org/patch/msgid/20230710091029.27503-1-tzimmermann@suse.de

Backmerge tag 'v6.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next

2023-06-19T06:01:25+00:00

Linux 6.4-rc7

Need this to pull in the msm work.

Signed-off-by: Dave Airlie

drm/exynos: fix race condition UAF in exynos_g2d_exec_ioctl

2023-06-07T04:03:16+00:00

If it is async, runqueue_node is freed in g2d_runqueue_worker on another
worker thread. So in extreme cases, if g2d_runqueue_worker runs first, and
then executes the following if statement, there will be use-after-free.

Signed-off-by: Min Li 
Reviewed-by: Andi Shyti 
Signed-off-by: Inki Dae

drm/exynos: vidi: fix a wrong error return

2023-06-07T04:03:17+00:00

Fix a wrong error return by dropping an error return.

When vidi driver is remvoed, if ctx->raw_edid isn't same as fake_edid_info
then only what we have to is to free ctx->raw_edid so that driver removing
can work correctly - it's not an error case.

Signed-off-by: Inki Dae 
Reviewed-by: Andi Shyti

drm/exynos: Use regular fbdev I/O helpers

2023-06-01T10:26:48+00:00

Use the regular fbdev helpers for framebuffer I/O instead of DRM's
helpers. Exynos does not use damage handling, so DRM's fbdev helpers
are mere wrappers around the fbdev code.

By using fbdev helpers directly within each DRM fbdev emulation,
we can eventually remove DRM's wrapper functions entirely.

v4:
	* use initializer macros for struct fb_ops
v3:
	* don't reorder Makefile rules (Sam)
v2:
	* use FB_IO_HELPERS option

Signed-off-by: Thomas Zimmermann 
Acked-by: Sam Ravnborg 
Cc: Inki Dae 
Cc: Seung-Woo Kim 
Cc: Kyungmin Park 
Cc: Krzysztof Kozlowski 
Cc: Alim Akhtar 
Link: https://patchwork.freedesktop.org/patch/msgid/20230530151228.22979-5-tzimmermann@suse.de

drm/exynos: fix g2d_open/close helper function definitions

2023-05-15T05:10:34+00:00

The empty stub functions are defined as global functions, which
causes a warning because of missing prototypes:

drivers/gpu/drm/exynos/exynos_drm_g2d.h:37:5: error: no previous prototype for 'g2d_open'
drivers/gpu/drm/exynos/exynos_drm_g2d.h:42:5: error: no previous prototype for 'g2d_close'

Mark them as 'static inline' to avoid the warning and to make
them behave as intended.

Fixes: eb4d9796fa34 ("drm/exynos: g2d: Convert to driver component API")
Signed-off-by: Arnd Bergmann 
Reviewed-by: Andi Shyti 
Signed-off-by: Inki Dae

drm/exynos: Implement fbdev emulation as in-kernel client

2023-04-17T07:47:55+00:00

Move code from ad-hoc fbdev callbacks into DRM client functions
and remove the old callbacks. The functions instruct the client
to poll for changed output or restore the display. The DRM core
calls both, the old callbacks and the new client helpers, from
the same places. The new functions perform the same operation as
before, so there's no change in functionality.

Replace all code that initializes or releases fbdev emulation
throughout the driver. Instead initialize the fbdev client by a
single call to exynos_fbdev_setup() after exynos has registered its
DRM device. As in most drivers, exynos' fbdev emulation now acts
like a regular DRM client.

The fbdev client setup consists of the initial preparation and the
hot-plugging of the display. The latter creates the fbdev device
and sets up the fbdev framebuffer. The setup performs display
hot-plugging once. If no display can be detected, DRM probe helpers
re-run the detection on each hotplug event.

A call to drm_dev_unregister() releases the client automatically.
No further action is required within exynos. If the fbdev framebuffer
has been fully set up, struct fb_ops.fb_destroy implements the
release. For partially initialized emulation, the fbdev client
reverts the initial setup.

Signed-off-by: Thomas Zimmermann 
Tested-by: Marek Szyprowski 
Signed-off-by: Inki Dae

drm/exynos: Initialize fbdev DRM client

2023-04-17T07:47:55+00:00

Initialize the fbdev client in the fbdev code with empty helper
functions. Also clean up the client. The helpers will later
implement various functionality of the DRM client. No functional
changes.

Signed-off-by: Thomas Zimmermann 
Tested-by: Marek Szyprowski 
Signed-off-by: Inki Dae

drm/exynos: Remove fb_helper from struct exynos_drm_private

2023-04-17T07:47:55+00:00

The DRM device stores a pointer to the fbdev helper. Remove struct
exynos_drm_private.fb_helper, which contains the same value. No
functional changes.

Signed-off-by: Thomas Zimmermann 
Tested-by: Marek Szyprowski 
Signed-off-by: Inki Dae

drm/exynos: Remove struct exynos_drm_fbdev

2023-04-17T07:47:55+00:00

Remove struct exynos_drm_fbdev, which is an empty wrapper around
struct drm_fb_helper. Use the latter directly. No functional changes.

Signed-off-by: Thomas Zimmermann 
Tested-by: Marek Szyprowski 
Signed-off-by: Inki Dae