Found this while browsing Bspec. Looks like it applies to both skl and kbl. v2: Also for bxt (Art). Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Sonika Jindal <sonika.jindal@xxxxxxxxx> Cc: Durgadoss R <durgadoss.r@xxxxxxxxx> Cc: "Pandiyan, Dhinakaran" <dhinakaran.pandiyan@xxxxxxxxx> Cc: "Runyan, Arthur J" <arthur.j.runyan@xxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_pm.c | 17 +++++++++++++++-- 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 0f99e67f2114..c51368744e9e 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -6043,6 +6043,7 @@ enum skl_disp_power_wells { #define CHICKEN_PAR1_1 _MMIO(0x42080) #define DPA_MASK_VBLANK_SRD (1 << 15) #define FORCE_ARB_IDLE_PLANES (1 << 14) +#define SKL_EDP_PSR_FIX_RDWRAP (1 << 3) #define _CHICKEN_PIPESL_1_A 0x420b0 #define _CHICKEN_PIPESL_1_B 0x420b4 diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index e0d5405a8b15..8d42261daf1f 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -58,6 +58,10 @@ static void bxt_init_clock_gating(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; + /* See Bspec note for PSR2_CTL bit 31, Wa#828:bxt */ + I915_WRITE(CHICKEN_PAR1_1, + I915_READ(CHICKEN_PAR1_1) | SKL_EDP_PSR_FIX_RDWRAP); + /* WaDisableSDEUnitClockGating:bxt */ I915_WRITE(GEN8_UCGCTL6, I915_READ(GEN8_UCGCTL6) | GEN8_SDEUNIT_CLOCK_GATE_DISABLE); @@ -6845,6 +6849,15 @@ static void gen8_set_l3sqc_credits(struct drm_i915_private *dev_priv, I915_WRITE(GEN7_MISCCPCTL, misccpctl); } +static void skylake_init_clock_gating(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + + /* See Bspec note for PSR2_CTL bit 31, Wa#828:skl,kbl */ + I915_WRITE(CHICKEN_PAR1_1, + I915_READ(CHICKEN_PAR1_1) | SKL_EDP_PSR_FIX_RDWRAP); +} + static void broadwell_init_clock_gating(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; @@ -7307,9 +7320,9 @@ static void nop_init_clock_gating(struct drm_device *dev) void intel_init_clock_gating_hooks(struct drm_i915_private *dev_priv) { if (IS_SKYLAKE(dev_priv)) - dev_priv->display.init_clock_gating = nop_init_clock_gating; + dev_priv->display.init_clock_gating = skylake_init_clock_gating; else if (IS_KABYLAKE(dev_priv)) - dev_priv->display.init_clock_gating = nop_init_clock_gating; + dev_priv->display.init_clock_gating = skylake_init_clock_gating; else if (IS_BROXTON(dev_priv)) dev_priv->display.init_clock_gating = bxt_init_clock_gating; else if (IS_BROADWELL(dev_priv)) -- 2.8.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx