20 Commits

Author SHA1 Message Date
Thomas Zimmermann
da68386d9e drm: Rename dp/ to display/
Rename dp/ to display/ to account for additional display-related
helpers, such as HDMI. Update all related include statements. No
functional changes.

Various drivers, such as i915 and amdgpu, use similar naming scheme
by putting code for video-output standards into a local display/
directory. The new directory's name is aligned with this convention.

v2:
	* update commit message (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220421073108.19226-3-tzimmermann@suse.de
2022-04-25 11:17:45 +02:00
Kees Cook
a2151490cc drm/dp: Fix OOB read when handling Post Cursor2 register
The link_status array was not large enough to read the Adjust Request
Post Cursor2 register, so remove the common helper function to avoid
an OOB read, found with a -Warray-bounds build:

drivers/gpu/drm/drm_dp_helper.c: In function 'drm_dp_get_adjust_request_post_cursor':
drivers/gpu/drm/drm_dp_helper.c:59:27: error: array subscript 10 is outside array bounds of 'const u8[6]' {aka 'const unsigned char[6]'} [-Werror=array-bounds]
   59 |         return link_status[r - DP_LANE0_1_STATUS];
      |                ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/drm_dp_helper.c:147:51: note: while referencing 'link_status'
  147 | u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_LINK_STATUS_SIZE],
      |                                          ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Replace the only user of the helper with an open-coded fetch and decode,
similar to drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c.

Cc: Daniel Vetter <daniel@ffwll.ch>
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: dri-devel@lists.freedesktop.org
Fixes: 79465e0ffeb9 ("drm/dp: Add helper to get post-cursor adjustments")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://lore.kernel.org/r/20220105173507.2420910-1-keescook@chromium.org
Signed-off-by: Thierry Reding <treding@nvidia.com>
2022-02-25 10:24:20 +01:00
Thomas Zimmermann
5b529e8d9c drm/dp: Move public DisplayPort headers into dp/
Move all public DisplayPort headers into dp/ and update users. No
functional changes.

v3:
	* rebased onto latest drm-tip

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114114535.29157-5-tzimmermann@suse.de
2022-01-17 11:25:44 +01:00
Thierry Reding
0472c21b83 drm/tegra: sor: Add DisplayPort support
Add support for regular DisplayPort on Tegra210 and Tegra186.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:54 +01:00
Thierry Reding
078c445733 drm/tegra: dp: Add DisplayPort link training helper
Add a helper that will perform link training as described in the
DisplayPort specification.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:53 +01:00
Thierry Reding
6a127160c4 drm/tegra: dp: Add support for eDP link rates
Parses additional link rates from DPCD if the sink supports eDP 1.4.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:53 +01:00
Thierry Reding
01f09f242e drm/tegra: dp: Add drm_dp_link_choose() helper
This helper chooses an appropriate configuration, according to the
bitrate requirements of the video mode and the capabilities of the
DisplayPort sink.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:52 +01:00
Thierry Reding
c4a2728852 drm/tegra: dp: Enable alternate scrambler reset when supported
If the sink is eDP and supports the alternate scrambler reset, enable
it.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:52 +01:00
Thierry Reding
553769ff8d drm/tegra: dp: Set channel coding on link configuration
Make use of ANSI 8B/10B channel coding if the DisplayPort sink supports
it.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:52 +01:00
Thierry Reding
ad7f2dda38 drm/tegra: dp: Read AUX read interval from DPCD
Store the AUX read interval from DPCD, so that it can be used to wait
for the durations given in the specification during link training.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:52 +01:00
Thierry Reding
7aa3cc540d drm/tegra: dp: Read eDP version from DPCD
If the sink supports eDP, read the eDP revision from it's DPCD.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:45 +01:00
Thierry Reding
4ff9ba5674 drm/tegra: dp: Read alternate scrambler reset capability from sink
Parse from the sink capabilities whether or not the eDP alternate
scrambler reset value of 0xfffe is supported.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:45 +01:00
Thierry Reding
6c651b13e4 drm/tegra: dp: Read channel coding capability from sink
Parse from the sink capabilities whether or not it supports ANSI 8B/10B
channel coding as specified in ANSI X3.230-1994, clause 11.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:45 +01:00
Thierry Reding
db199502fa drm/tegra: dp: Read TPS3 capability from sink
The TPS3 capability can be exposed by DP 1.2 and later sinks if they
support the alternative training pattern for channel equalization.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:45 +01:00
Thierry Reding
cb072eebfa drm/tegra: dp: Read fast training capability from link
While probing the DisplayPort link, query the fast training capability.
If supported, drivers can use the fast link training sequence instead of
the more involved full link training sequence.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:44 +01:00
Thierry Reding
480770440a drm/tegra: dp: Probe link using existing parsing helpers
Use existing parsing helpers to probe a DisplayPort link.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:44 +01:00
Thierry Reding
27ba465ce3 drm/tegra: dp: Turn link capabilities into booleans
Rather than storing capabilities as flags in an integer, use a separate
boolean per capability. This simplifies the code that checks for these
capabilities.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:44 +01:00
Thierry Reding
c728e2d4a6 drm/tegra: dp: Track link capabilities alongside settings
Store capabilities in max_* fields and add separate fields for the
currently selected settings.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:44 +01:00
Thierry Reding
1abd6b3304 drm/tegra: dp: Add drm_dp_link_reset() implementation
Subsequent patches will add non-volatile fields to struct drm_dp_link,
so introduce a function to zero out only the volatile fields.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-10-28 11:18:44 +01:00
Thierry Reding
9a42c7c647 drm/tegra: Move drm_dp_link helpers to Tegra DRM
During the discussion of patches that enhance the drm_dp_link helpers it
was concluded that these helpers aren't very useful to begin with. After
all other drivers have been converted not to use these helpers anymore,
move these helpers into the last remaining user: Tegra DRM.

If at some point these helpers are deemed more widely useful, they can
be moved out into the DRM DP helpers again.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191021143437.1477719-14-thierry.reding@gmail.com
2019-10-23 18:22:10 +02:00