From 80c6d6804f31451848a3956a70c2bcb1f07cfcb0 Mon Sep 17 00:00:00 2001 From: Aurabindo Pillai Date: Wed, 15 Feb 2023 12:51:20 -0500 Subject: drm/amd/display: disable SubVP + DRR to prevent underflow [Why&How] Temporarily disable SubVP+DRR since Xorg has an architectural limitation where freesync will not work in a multi monitor configuration. SubVP+DRR requires that freesync be working. Whether OS has variable refresh setting enabled or not, the state on the crtc remains same unless an application requests VRR. Due to this, there is no way to know whether freesync will actually work or not while we are on the desktop from the kernel's perspective. If userspace does not have a limitation with multi-display freesync (for example wayland), then this feature can be enabled by adding a dcfeaturemask option to amdgpu on the kernel cmdline like: amdgpu.dcfeaturemask=0x200 Signed-off-by: Aurabindo Pillai Reviewed-by: Rodrigo Siqueira Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c') 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 5a2e09e97dd5..c420bce47acb 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1604,6 +1604,11 @@ static int amdgpu_dm_init(struct amdgpu_device *adev) if (amdgpu_dc_feature_mask & DC_DISABLE_LTTPR_DP2_0) init_data.flags.allow_lttpr_non_transparent_mode.bits.DP2_0 = true; + /* Disable SubVP + DRR config by default */ + init_data.flags.disable_subvp_drr = true; + if (amdgpu_dc_feature_mask & DC_ENABLE_SUBVP_DRR) + init_data.flags.disable_subvp_drr = false; + init_data.flags.seamless_boot_edp_requested = false; if (check_seamless_boot_capability(adev)) { -- cgit v1.2.3-70-g09d2