[PATCH] drm/amdgpu/display: add dc feature mask for psr enablement

[Roman.Li at amd.com]

From: Roman Li <Roman.Li at amd.com>

[Why]
Adding psr mask to dc features allows selectively disable/enable psr.
Current psr implementation may not work with non-pageflipping application.
Until resolved it should be disabled by default.

[How]
Add dcfeaturemask for psr enablement. Disable by default.
To enable set amdgpu.dcfeaturemask=0x8 in grub kernel command line.

Signed-off-by: Roman Li <Roman.Li at amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
 drivers/gpu/drm/amd/include/amd_shared.h          | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 1cf4beb..0f08879 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2424,7 +2424,8 @@ static int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev)
 		} else if (dc_link_detect(link, DETECT_REASON_BOOT)) {
 			amdgpu_dm_update_connector_after_detect(aconnector);
 			register_backlight_device(dm, link);
-			amdgpu_dm_set_psr_caps(link);
+			if (amdgpu_dc_feature_mask & DC_PSR_MASK)
+				amdgpu_dm_set_psr_caps(link);
 		}
 
 
diff --git a/drivers/gpu/drm/amd/include/amd_shared.h b/drivers/gpu/drm/amd/include/amd_shared.h
index 8889aac..1daa221 100644
--- a/drivers/gpu/drm/amd/include/amd_shared.h
+++ b/drivers/gpu/drm/amd/include/amd_shared.h
@@ -143,6 +143,7 @@ enum PP_FEATURE_MASK {
 enum DC_FEATURE_MASK {
 	DC_FBC_MASK = 0x1,
 	DC_MULTI_MON_PP_MCLK_SWITCH_MASK = 0x2,
+	DC_PSR_MASK = 0x8,
 };
 
 enum amd_dpm_forced_level;
-- 
2.7.4