kernel/linux.git/drivers/gpu/drm/amd/display/modules, branch v6.18.21

drm/amd/display: Allow VRR params change if unsynced with the stream

2025-11-12T03:50:53+00:00

[Why] When changing resolution (e.g., 4K → FHD) in mirror/clone mode with certain monitors, the monitor blanks and loses connection due to an early exit in vrr_settings_require_update(). The function only checks if VRR state, fixed refresh target, or min/max refresh rate range has changed. During mode changes, if the calculated min/max refresh values remain the same even though the stream's v_total changed, the function returns early without updating vrr_params.adjust.v_total_min/max, leaving the monitor's VRR timing parameters unsynced with the new mode, causing it to blank out. [How] Explicitly adjust VRR parameters to the stream's nominal v_total when VRR is supported, but inactive. Fixes: 6d31602a9f57 ("drm/amd/display: more liberal vmin/vmax update for freesync") Reviewed-by: Aurabindo Pillai Signed-off-by: Ivan Lipski Signed-off-by: Fangzhi Zuo Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 607df8248a011524211ee34850345305a1913f9e)

drm/amd/display: Add HDCP policy control

2025-09-05T21:38:40+00:00

[Why] DM should be able to control HDCP retry limit via configurable parameter. [How] Expose a retry_limit parameter for controlling the maximum number of retries and lift the hardcode out to DM. Reviewed-by: Nicholas Kazlauskas Reviewed-by: Aric Cyr Signed-off-by: Oleh Kuzhylnyi Signed-off-by: Wayne Lin Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Remove redundant ternary operators

2025-09-05T21:38:39+00:00

For ternary operators in the form of "a ? true : false" or "a ? false : true", if 'a' itself returns a boolean result, the ternary operator can be omitted. Remove redundant ternary operators to clean up the code. Signed-off-by: Liao Yuanhong Signed-off-by: Alex Deucher

drm/amd/display: Add null pointer check in mod_hdcp_hdcp1_create_session()

2025-08-18T20:59:29+00:00

The function mod_hdcp_hdcp1_create_session() calls the function get_first_active_display(), but does not check its return value. The return value is a null pointer if the display list is empty. This will lead to a null pointer dereference. Add a null pointer check for get_first_active_display() and return MOD_HDCP_STATUS_DISPLAY_NOT_FOUND if the function return null. This is similar to the commit c3e9826a2202 ("drm/amd/display: Add null pointer check for get_first_active_display()"). Fixes: 2deade5ede56 ("drm/amd/display: Remove hdcp display state with mst fix") Signed-off-by: Chenyuan Yang Reviewed-by: Alex Hung Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Initial support for SmartMux

2025-07-15T18:07:53+00:00

SmartMux is a mechanism to switch the GPU being used for scanout in a hybrid configuration. This is used for devices with an eDP and two GPUs. This is only valid when the system has a physical switch (Multiplexer) in the board to switch between the two GPUs. When a graphically intensive workload like a game is being run, the system can be switch the active display to the dGPU, so that we can avoid copying the buffer from dGPU to APU for scanout. This helps with latency and FPS. When power consumption is preferred, the system can be switched to the APU. Reviewed-by: Alvin Lee Signed-off-by: Aurabindo Pillai Signed-off-by: Ivan Lipski Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Added case for when RR equals panel's max RR using freesync

2025-06-30T15:59:00+00:00

[WHY] Rounding error sometimes occurs when the refresh rate is equal to a panel's max refresh rate, causing HDMI compliance failures. [HOW] Added a case so that we round up to avoid v_total_min to be below a panel's minimum bound. Reviewed-by: Jun Lei Signed-off-by: Harold Sun Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Remove redundant macro of refresh rate

2025-06-24T13:55:58+00:00

[Why&How] Found that we add redundant macro on refresh rate when calculating vtotal, so we remove it. Reviewed-by: Robin Chen Signed-off-by: Weiguang Li Signed-off-by: Fangzhi Zuo Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Add null pointer check for get_first_active_display()

2025-05-29T14:57:13+00:00

The function mod_hdcp_hdcp1_enable_encryption() calls the function get_first_active_display(), but does not check its return value. The return value is a null pointer if the display list is empty. This will lead to a null pointer dereference in mod_hdcp_hdcp2_enable_encryption(). Add a null pointer check for get_first_active_display() and return MOD_HDCP_STATUS_DISPLAY_NOT_FOUND if the function return null. Fixes: 2deade5ede56 ("drm/amd/display: Remove hdcp display state with mst fix") Signed-off-by: Wentao Liang Reviewed-by: Alex Hung Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org # v5.8

drm/amd/display: HDCP Locality check using DMUB Fused IO

2025-04-07T22:01:07+00:00

[Why] HDCP locality check has strict timing requirements, currently broken due to reliance on msleep which does not guarantee accuracy. The PR moves the write-poll-read sequence into DMUB using new generic Fused IO interface, where the timing accuracy is greatly improved. New flow is enabled using DCN resource capability bit (none for now), or using a debug flag. [How] * Extended mod_hdcp_config with new function for requesting DMUB to execute a sequence of fused I2C/AUX commands and synchronously wait until an outbox reply arrives or a timeout expires. * If the timeout expires, send an abort to DMUB. * Update HDCP to use the DMUB for locality check if supported. * Add DC_HDCP_LC_FORCE_FW_ENABLE and DC_HDCP_LC_ENABLE_SW_FALLBACK. * Make the first enable new flow regardless of resource capabilities. * Make the second enable fallback to old SW flow. * Clean up makefile source file listings for easier updates. Reviewed-by: Alvin Lee Signed-off-by: Dominik Kaszewski Signed-off-by: Roman Li Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Fix BT2020 YCbCr limited/full range input

2025-02-19T20:14:10+00:00

[Why] BT2020 YCbCr input is not handled properly when full range quantization is used and limited range is not supported at all. [How] - Add enums for BT2020 YCbCr limited/full range - Add limited range CSC matrix Reviewed-by: Krunoslav Kovac Signed-off-by: Ilya Bakoulin Signed-off-by: Roman Li Tested-by: Robert Mader Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher