From: Mario Limonciello mario.limonciello@amd.com
[WHY] DMUB locking is important to make sure that registers aren't accessed while in PSR. Previously it was enabled but caused a deadlock in situations with multiple eDP panels.
[HOW] Detect if multiple eDP panels are in use to decide whether to use lock. Refactor the function so that the first check is for PSR-SU and then replay is in use to prevent having to look up number of eDP panels for those configurations.
Fixes: f245b400a223 ("Revert "drm/amd/display: Use HW lock mgr for PSR1"") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3965 Reviewed-by: ChiaHsuan Chung chiahsuan.chung@amd.com Signed-off-by: Alex Hung alex.hung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org (cherry picked from commit acbf16a6ae775b4db86f537448cc466288aa307e) [superm1: Adjust for missing replay support bfeefe6ea5f1, Adjust for dc_get_edp_links not being renamed from get_edp_links()] Signed-off-by: Mario Limonciello mario.limonciello@amd.com --- .../gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c b/drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c index 3f32e9c3fbaf..13995b6fb865 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c @@ -67,5 +67,17 @@ bool should_use_dmub_lock(struct dc_link *link) { if (link->psr_settings.psr_version == DC_PSR_VERSION_SU_1) return true; + + /* only use HW lock for PSR1 on single eDP */ + if (link->psr_settings.psr_version == DC_PSR_VERSION_1) { + struct dc_link *edp_links[MAX_NUM_EDP]; + int edp_num; + + get_edp_links(link->dc, edp_links, &edp_num); + + if (edp_num == 1) + return true; + } + return false; }
[ Sasha's backport helper bot ]
Hi,
Summary of potential issues: ⚠️ Found matching upstream commit but patch is missing proper reference to it
Found matching upstream commit: acbf16a6ae775b4db86f537448cc466288aa307e
WARNING: Author mismatch between patch and found commit: Backport author: Mario Limonciellosuperm1@kernel.org Commit author: Mario Limonciellomario.limonciello@amd.com
Status in newer kernel trees: 6.13.y | Not found 6.12.y | Not found 6.6.y | Not found
Note: The patch differs from the upstream commit: --- 1: acbf16a6ae775 ! 1: 798c6bedbaa1a drm/amd/display: Use HW lock mgr for PSR1 when only one eDP @@ Commit message Fixes: f245b400a223 ("Revert "drm/amd/display: Use HW lock mgr for PSR1"") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3965 Reviewed-by: ChiaHsuan Chung chiahsuan.chung@amd.com - Signed-off-by: Mario Limonciello mario.limonciello@amd.com Signed-off-by: Alex Hung alex.hung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com - (cherry picked from commit ed569e1279a3045d6b974226c814e071fa0193a6) Cc: stable@vger.kernel.org + (cherry picked from commit acbf16a6ae775b4db86f537448cc466288aa307e) + [superm1: Adjust for missing replay support bfeefe6ea5f1, + Adjust for dc_get_edp_links not being renamed from get_edp_links()] + Signed-off-by: Mario Limonciello mario.limonciello@amd.com
## drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c ## @@ drivers/gpu/drm/amd/display/dc/dce/dmub_hw_lock_mgr.c: bool should_use_dmub_lock(struct dc_link *link) - if (link->replay_settings.replay_feature_enabled) + { + if (link->psr_settings.psr_version == DC_PSR_VERSION_SU_1) return true; - ++ + /* only use HW lock for PSR1 on single eDP */ + if (link->psr_settings.psr_version == DC_PSR_VERSION_1) { + struct dc_link *edp_links[MAX_NUM_EDP]; + int edp_num; + -+ dc_get_edp_links(link->dc, edp_links, &edp_num); ++ get_edp_links(link->dc, edp_links, &edp_num); + + if (edp_num == 1) + return true; ---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-6.1.y | Success | Success |
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Mario Limonciello -
Sasha Levin