From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> commit b2d73debfdc16b742e64948dc4461876af3f8c10 upstream. Looks like skl/bxt/derivatives also need the plane stride stretch w/a when using async flips and VT-d is enabled, or else we get corruption on screen. To my surprise this was even documented in bspec, but only as a note on the CHICHKEN_PIPESL register description rather than on the w/a list. So very much the same thing as on HSW/BDW, except the bits moved yet again. Cc: stable@xxxxxxxxxxxxxxx Cc: Karthik B S <karthik.b.s@xxxxxxxxx> Fixes: 55ea1cb178ef ("drm/i915: Enable async flips in i915") Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20210930190943.17547-1-ville.syrjala@xxxxxxxxxxxxxxx Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx> (cherry picked from commit d08df3b0bdb25546e86dc9a6c4e3ec0c43832299) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_reg.h | 5 +++++ drivers/gpu/drm/i915/intel_pm.c | 12 ++++++++++++ 2 files changed, 17 insertions(+) --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -8150,6 +8150,11 @@ enum { #define HSW_SPR_STRETCH_MAX_X1 REG_FIELD_PREP(HSW_SPR_STRETCH_MAX_MASK, 3) #define HSW_FBCQ_DIS (1 << 22) #define BDW_DPRS_MASK_VBLANK_SRD (1 << 0) +#define SKL_PLANE1_STRETCH_MAX_MASK REG_GENMASK(1, 0) +#define SKL_PLANE1_STRETCH_MAX_X8 REG_FIELD_PREP(SKL_PLANE1_STRETCH_MAX_MASK, 0) +#define SKL_PLANE1_STRETCH_MAX_X4 REG_FIELD_PREP(SKL_PLANE1_STRETCH_MAX_MASK, 1) +#define SKL_PLANE1_STRETCH_MAX_X2 REG_FIELD_PREP(SKL_PLANE1_STRETCH_MAX_MASK, 2) +#define SKL_PLANE1_STRETCH_MAX_X1 REG_FIELD_PREP(SKL_PLANE1_STRETCH_MAX_MASK, 3) #define CHICKEN_PIPESL_1(pipe) _MMIO_PIPE(pipe, _CHICKEN_PIPESL_1_A, _CHICKEN_PIPESL_1_B) #define _CHICKEN_TRANS_A 0x420c0 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -76,6 +76,8 @@ struct intel_wm_config { static void gen9_init_clock_gating(struct drm_i915_private *dev_priv) { + enum pipe pipe; + if (HAS_LLC(dev_priv)) { /* * WaCompressedResourceDisplayNewHashMode:skl,kbl @@ -89,6 +91,16 @@ static void gen9_init_clock_gating(struc SKL_DE_COMPRESSED_HASH_MODE); } + for_each_pipe(dev_priv, pipe) { + /* + * "Plane N strech max must be programmed to 11b (x1) + * when Async flips are enabled on that plane." + */ + if (!IS_GEMINILAKE(dev_priv) && intel_vtd_active()) + intel_uncore_rmw(&dev_priv->uncore, CHICKEN_PIPESL_1(pipe), + SKL_PLANE1_STRETCH_MAX_MASK, SKL_PLANE1_STRETCH_MAX_X1); + } + /* See Bspec note for PSR2_CTL bit 31, Wa#828:skl,bxt,kbl,cfl */ intel_uncore_write(&dev_priv->uncore, CHICKEN_PAR1_1, intel_uncore_read(&dev_priv->uncore, CHICKEN_PAR1_1) | SKL_EDP_PSR_FIX_RDWRAP);