diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 5a1a984d74c9..2aff1bbcfc83 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -556,6 +556,8 @@ #define IIR 0x020a4 #define IMR 0x020a8 #define ISR 0x020ac +#define VLV_GUNIT_CLOCK_GATE 0x182060 +#define GCFG_DIS (1<<8) #define VLV_IIR_RW 0x182084 #define VLV_IER 0x1820a0 #define VLV_IIR 0x1820a4 diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 871bfe49b913..10e6d6c21960 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3755,6 +3755,13 @@ static void valleyview_init_clock_gating(struct drm_device *dev) PIPEA_HLINE_INT_EN | PIPEA_VBLANK_INT_EN | SPRITEB_FLIPDONE_INT_EN | SPRITEA_FLIPDONE_INT_EN | PLANEA_FLIPDONE_INT_EN); + + /* + * WaDisableVLVClockGating_VBIIssue + * Disable clock gating on th GCFG unit to prevent a delay + * in the reporting of vblank events. + */ + I915_WRITE(VLV_GUNIT_CLOCK_GATE, GCFG_DIS); } static void g4x_init_clock_gating(struct drm_device *dev)