From ed3803533c7bf7df88bc3fc9f70bd317e1228ea8 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Timur=20Krist=C3=B3f?= Date: Thu, 28 Aug 2025 17:11:09 +0200 Subject: [PATCH] drm/amd/pm: Disable MCLK switching with non-DC at 120 Hz+ (v2) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit According to pp_pm_compute_clocks the non-DC display code has "issues with mclk switching with refresh rates over 120 hz". The workaround is to disable MCLK switching in this case. Do the same for legacy DPM. Fixes: 6ddbd37f1074 ("drm/amd/pm: optimize the amdgpu_pm_compute_clocks() implementations") Reviewed-by: Alex Deucher Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/pm/amdgpu_dpm_internal.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/amd/pm/amdgpu_dpm_internal.c b/drivers/gpu/drm/amd/pm/amdgpu_dpm_internal.c index 42efe838fa85c..2d2d2d5e67634 100644 --- a/drivers/gpu/drm/amd/pm/amdgpu_dpm_internal.c +++ b/drivers/gpu/drm/amd/pm/amdgpu_dpm_internal.c @@ -66,6 +66,13 @@ u32 amdgpu_dpm_get_vblank_time(struct amdgpu_device *adev) (amdgpu_crtc->v_border * 2)); vblank_time_us = vblank_in_pixels * 1000 / amdgpu_crtc->hw_mode.clock; + + /* we have issues with mclk switching with + * refresh rates over 120 hz on the non-DC code. + */ + if (drm_mode_vrefresh(&amdgpu_crtc->hw_mode) > 120) + vblank_time_us = 0; + break; } } -- 2.47.3