From 08d0e875aefe72c63076a768a368126ea74a1e3e Mon Sep 17 00:00:00 2001 From: Mahesh Kumar Date: Mon, 9 Apr 2018 09:11:07 +0530 Subject: [PATCH] drm/i915/skl+: nv12 workaround disable WM level 1-7 Display Workaround #0826 (SKL:ALL BXT:ALL) & #1059(CNL:A) Hardware sometimes fails to wake memory from pkg C states fetching the last few lines of planar YUV 420 (NV12) planes. This causes intermittent underflow and corruption. WA: Disable package C states or do not enable latency levels 1 through 7 (WM1 - WM7) on NV12 planes. v2: Addressed review comments by Maarten. v3: Adding reviewed by tag from Shashank Sharma v4: Added reviewed by from Juha-Pekka Heikkila v5: Rebased the series Reviewed-by: Juha-Pekka Heikkila Reviewed-by: Shashank Sharma Reviewed-by: Maarten Lankhorst Signed-off-by: Mahesh Kumar Signed-off-by: Vidya Srinivas Signed-off-by: Maarten Lankhorst Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-9-git-send-email-vidya.srinivas@intel.com --- drivers/gpu/drm/i915/intel_pm.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 707843012dff..9d5a7b3e9716 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4653,6 +4653,17 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv, } } + /* + * Display WA #826 (SKL:ALL, BXT:ALL) & #1059 (CNL:A) + * disable wm level 1-7 on NV12 planes + */ + if (wp->is_planar && level >= 1 && + (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv) || + IS_CNL_REVID(dev_priv, CNL_REVID_A0, CNL_REVID_A0))) { + result->plane_en = false; + return 0; + } + /* The number of lines are ignored for the level 0 watermark. */ result->plane_res_b = res_blocks; result->plane_res_l = res_lines;