| From 58d7e3e427db1bd68f33025519a9468140280a75 Mon Sep 17 00:00:00 2001 |
| From: Alex Deucher <alexander.deucher@amd.com> |
| Date: Thu, 11 May 2017 13:14:14 -0400 |
| Subject: drm/radeon/ci: disable mclk switching for high refresh rates (v2) |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Alex Deucher <alexander.deucher@amd.com> |
| |
| commit 58d7e3e427db1bd68f33025519a9468140280a75 upstream. |
| |
| Even if the vblank period would allow it, it still seems to |
| be problematic on some cards. |
| |
| v2: fix logic inversion (Nils) |
| |
| bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868 |
| |
| Acked-by: Christian Kรถnig <christian.koenig@amd.com> |
| Signed-off-by: Alex Deucher <alexander.deucher@amd.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/gpu/drm/radeon/ci_dpm.c | 6 ++++++ |
| 1 file changed, 6 insertions(+) |
| |
| --- a/drivers/gpu/drm/radeon/ci_dpm.c |
| +++ b/drivers/gpu/drm/radeon/ci_dpm.c |
| @@ -776,6 +776,12 @@ bool ci_dpm_vblank_too_short(struct rade |
| u32 vblank_time = r600_dpm_get_vblank_time(rdev); |
| u32 switch_limit = pi->mem_gddr5 ? 450 : 300; |
| |
| + /* disable mclk switching if the refresh is >120Hz, even if the |
| + * blanking period would allow it |
| + */ |
| + if (r600_dpm_get_vrefresh(rdev) > 120) |
| + return true; |
| + |
| if (vblank_time < switch_limit) |
| return true; |
| else |
