Add KUnit tests for amdgpu_dm_link_supports_replay() which
validates panel replay capability based on link DPCD caps,
freesync state, and VSDB info. Nine test cases cover the
positive path and each individual failure condition.

Export the function under CONFIG_DRM_AMD_DC_KUNIT_TEST and
add the amdgpu include path to the tests Makefile so that
amdgpu_dm.h can resolve amdgpu_mode.h types under UML.

Assisted-by: Copilot:Claude-Opus-4.6
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why & How]
Refactors dm to utilize the power module for managing
replay, PSR, and backlight control functionalities.

Key changes:
- Introduced replay / PSR events to enable / disable replay / PSR.
- Implemented replay rate control and power option
- Refactored backlight control by using the power module.
- Enhanced handling of VRR within replay and PSR logic.

Reviewed-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why]
IGT CRC tests fail on replay panels due to invalid CRC values
captured when replay is active.

[How]
- Disable replay when CRC source is enabled; set flag to
  prevent unexpected re-enable
- Reset flag when CRC source is disabled to allow replay

Reviewed-by: ChiaHsuan (Tom) Chung <chiahsuan.chung@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Matthew Stewart <matthew.stewart2@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[WHY]
Panel Replay is not an eDP-specific function.

[HOW]
Create new Panel Replay source files and move the Panel Replay
functions from the eDP files to the new files. Additionally, create
a new link_service construct function to assign the related
function pointers.

Reviewed-by: Robin Chen <robin.chen@amd.com>
Signed-off-by: Peichen Huang <PeiChen.Huang@amd.com>
Signed-off-by: Matthew Stewart <matthew.stewart2@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why & How]
The change is to optimize the Replay power saving by
reducing the refresh rate with frame skipping mode

Reviewed-by: Robin Chen <robin.chen@amd.com>
Signed-off-by: Chuntao Tso <chunttso@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[WHY]
Header file name "link.h" collides with system header when dc is
compiled as a user-mode library

[WHAT]
Rename link.h to link_service.h to avoid name collision

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Signed-off-by: Wesley Chalmers <Wesley.Chalmers@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why]
All files should be properly classified.

[How]
Add missing SPDX-License-Identifier.

Reviewed-by: Sun peng (Leo) Li <sunpeng.li@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why & How]
User can get the panel replay capability and state for debug.

sudo cat /sys/kernel/debug/dri/0/eDP-1/replay_capability
"Sink support: no" - if panel doesn't support Replay
"Sink support: yes" - if panel supports Replay
"Driver support: no\n" - if driver doesn't support Replay
"Driver support: yes\n" - if driver supports Replay

sudo cat /sys/kernel/debug/dri/0/eDP-1/replay_state
It will return current panel replay state

Reviewed-by: Sun peng Li <sunpeng.li@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

[Why]
Enable the Panel Replay if eDP panel and ASIC support.
(prioritize Panel Replay over PSR)

[How]
- Setup the Panel Replay config during the device init
  (prioritize Panel Replay over PSR).
- Separate the Replay init function into two functions
  amdgpu_dm_link_setup_replay() and amdgpu_dm_set_replay_caps()
  to fix the issue in the earlier commit that cause PSR and Replay
  enabled at the same time.

Reviewed-by: Sun peng Li <sunpeng.li@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Fixes the following coccicheck:

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_replay.c:94:102-107: WARNING: conversion to bool not needed here
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_replay.c:102:72-77: WARNING: conversion to bool not needed here

Cc: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>