drm/amd/display: Fix uninitialized variables in DC

This fixes 29 UNINIT issues reported by Coverity.

Reviewed-by: Hersen Wu <hersenxs.wu@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Enable new interface design for alternate scrambling

[why & how]
To enable a new interface so alternate scrambling can be done via
security module.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Sung Joon Kim <sungjoon.kim@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Add align done check

[WHY]
We Double-check link status if training successful,
but miss the lane align status.

[HOW]
Add the lane align status check

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Zhikai Zhai <zhikai.zhai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Remove Legacy FIXED_VS Transparent LT Sequence

The New sequence has been in use in DCN314 with no regressions
introduced. Therefore, it is safe to enable this sequence for all
devices using FIXED_VS retimers. So, remove the legacy codepath and its
associated config flag.

Reviewed-by: Ovidiu Bunea <ovidiu.bunea@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Add align done check

[WHY]
We Double-check link status if training successful,
but miss the lane align status.

[HOW]
Add the lane align status check

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Zhikai Zhai <zhikai.zhai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: avoid stringop-overflow warnings for dp_decide_lane_settings()

gcc prints a warning about a possible array overflow for a couple of
callers of dp_decide_lane_settings() after commit 1b56c90018f0 ("Makefile:
Enable -Wstringop-overflow globally"):

drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c: In function 'dp_perform_fixed_vs_pe_training_sequence_legacy':
drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c:426:25: error: 'dp_decide_lane_settings' accessing 4 bytes in a region of size 1 [-Werror=stringop-overflow=]
426 | dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
427 | lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c:426:25: note: referencing argument 4 of type 'union dpcd_training_lane[4]'

I'm not entirely sure what caused this, but changing the prototype to expect
a pointer instead of an array avoids the warnings.

Fixes: 7727e7b60f82 ("drm/amd/display: Improve robustness of FIXED_VS link training at DP1 rates")
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Add link encoding to timing BW calculation parameters

[Why]
There certain cases where the timing BW is dependent on the type of link
encoding in use. Thus to calculate the correct BW required for a given
timing, the link encoding should be added as a parameter.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Alan Liu <haoping.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: lower dp link training message level

[Why] some test apps report dp link training waring even dp
training pass. there are 4 tries of lt within
perform_link_training_with_retries. if lt pass within 4 tries,
it will NOT be reated as lt failure. for each try of lt, if lt
fails, current driver implementation prints message at warning
level. this let people think dp lt does not work properly.

[How] for 1st, 2nd and 3rd try of lt, print message at debug
level. for the 4th try of lt, print message at warning level.

Reviewed-by: Jerry Zuo <jerry.zuo@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Apply correct panel mode when reinitializing hardware

[Why]
When link training during engine recovery, ASSR might fail causing panel
mode to be reset to default. This should not happen for eDP as it
will prevent the panel from turning back on.

[How]
Added dp_panel_mode to struct dc_link to remember previously applied
panel mode. Do not reset panel mode to default while performing link
training if previously used panel mode = eDP.

Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Michael Mityushkin <michael.mityushkin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Apply correct panel mode when reinitializing hardware

[Why]
When link training during engine recovery, ASSR might fail causing panel
mode to be reset to default. This should not happen for eDP as it
will prevent the panel from turning back on.

[How]
Added dp_panel_mode to struct dc_link to remember previously applied
panel mode. Do not reset panel mode to default while performing link
training if previously used panel mode = eDP.

Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Michael Mityushkin <michael.mityushkin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Add logging for DP link traning Test Pattern Seqeunces

Add some more logging for DP link traning test pattern seqeunces
for better debugging.

Cc: Fangzhi Zuo <Jerry.Zuo@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display : Log DP link training downspread info

Update the existing log with DP LT downspread info:

[Downstream devices shall support down spreading of the link clock.
The down-spread amplitude shall either be disabled (0.0%) or up to 0.5%,
as written by the upstream device to the DOWNSPREAD_CTRL register
(DPCD 00107h). The modulation frequency range shall be 30 to 33 kHz]

Besides, fix checkpatch warning:

CHECK: Alignment should match open parenthesis

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Improve robustness of FIXED_VS link training at DP1 rates

[WHY]
New sequence for transparent mode DP1.x link training was provided by LTTPR
vendor

[HOW]
Implement new FIXED_VS sequence, increase LT retry count to minimize
any potential intermittent lightup failures

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Add support for 6.75 GBps link rate

[Why]
The latest eDP spec version 1.5 defines a new generic link
rate of 6.75 Gbps/Lane, which needs to be supported in the driver.

[How]
Added new element to the dc_link_rate enum

Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Artem Grishin <Artem.Grishin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display/dc/link/protocols/link_dp_training: Remove set but unused variable 'result'

Fixes the following W=1 kernel build warning(s):

drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_training.c: In function ‘perform_link_training_with_retries’:
drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_dp_training.c:1586:38: warning: variable ‘result’ set but not used [-Wunused-but-set-variable]

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Wenjing Liu <wenjing.liu@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: convert link.h functions to function pointer style

[Why & How]
All dc subcomponents should call another dc component via function pointers
stored in a component structure. This is part of dc coding convention since
the beginning. The reason behind this is to improve encapsulation and
polymorphism. The function contract is extracted into a single link service
structure defined in link.h header file and implemented only in link_factory.c instead
of spreading across multiple files in link component file structure.

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Drop unnecessary DCN guards

[Why & How]
DC is littered with many DCN guards that are not needed.
Drop them.

Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: replace all dc_link function call in link with link functions

[why]
Link components should not reply on dc_link_exports to access link function in
other link components.

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move dc_link functions in protocols folder to dc_link_exports

[why]
link component should only have one interface serving dc.

[how]
We are moving dc_link functions exposed to DM to dc_link_exports
and unify link component interface in link.h with function pointer
to match the style of other dc component. This is the third step to move
dc_link functions under protocols folder to dc_link_exports.

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP

[Why & How]
There is no reason we still need a config option for this.

Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: Reduce CPU busy-waiting for long delays

[WHY]
udelay should not be used for long waits since it keeps CPU active,
wasting power.

[HOW]
Use fsleep where acceptable to allow CPU cores to be parked by the scheduler.

Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: break down dc_link.c

[why]
dc_link contains over 30k line of code, the decision is to break it
down to files residing in link folder based on functionality. This
change is the last break down change which will remove dc_link.c
file after everything is broken down.

[how]
Move remaining dc_link.c functions into link_detection, link_dpms,
link_validation, link_resource, and link_fpga and remove dc_link.

Reviewed-by: George Shen <George.Shen@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: merge dc_link_dp into dc_link

[why]
Temporarly merge dc_link_dp functions into dc_link for the
purpose of removing dc_link_dp files. This is a transitional
change for later commits where we will further refactor dc_link
file.

Reviewed-by: George Shen <George.Shen@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move dp irq handler functions from dc_link_dp to link_dp_irq_handler

Create new files link_dp_irq_handler.c and link_dp_irq_handler.h, and
move DP irq handler functions into them.

Reviewed-by: George Shen <George.Shen@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: move eDP panel control logic to link_edp_panel_control

Create new file link_edp_panel_control.c and link_edp_panel_control.h,
and move eDP panel control logic into them.

Reviewed-by: George Shen <George.Shen@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amd/display: create accessories, hwss and protocols sub folders in link

[why]
link component contains three sub folders:

accessories - utilities for improving testability, logging or tracing, doesn't impact
end user use cases.

protocols - specs defined protocols used in end user use cases

hwss - hwss owned link_hwss object, served as an abstraction layer in hwss to
access various types of encoder/phy/dpia endpoints in a unified interface.

sooner we will have files directly under link folder one for the implementation of
each major link behavior such as link_create, link_detect, link_validate
and link_set_dpms.

Reviewed-by: George Shen <George.Shen@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>