From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> 85x also has a similar AGPBUSY# bit as gen3. Enable it to make sure vblank interrupts don't get dealyed during C3 state. There's also another bit which controls whether AGPBUSY# is asserted based on pending cacheable cycles and interrupts, or just based on pending commands in the ring and interrupts. Select the cacheable cycles mode since that seems to be the new way of doing things in 85x, and it does give slightly better C3 residency numbers with glxgears running. Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_reg.h | 4 ++++ drivers/gpu/drm/i915/intel_pm.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index e6bff6c..cd8e2d5 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -919,6 +919,10 @@ #define MI_ARB_DISPLAY_PRIORITY_A_B (0 << 0) /* display A > display B */ #define MI_ARB_DISPLAY_PRIORITY_B_A (1 << 0) /* display B > display A */ +#define MI_STATE 0x020e4 /* gen2 only */ +#define MI_AGPBUSY_INT_EN (1 << 1) /* 85x only */ +#define MI_AGPBUSY_830_MODE (1 << 0) /* 85x only */ + #define CACHE_MODE_0 0x02120 /* 915+ only */ #define CM0_PIPELINED_RENDER_FLUSH_DISABLE (1<<8) #define CM0_IZ_OPT_DISABLE (1<<6) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index e8b748d..b6ab781 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5130,6 +5130,10 @@ static void i85x_init_clock_gating(struct drm_device *dev) struct drm_i915_private *dev_priv = dev->dev_private; I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE); + + /* interrupts should cause a wake up from C3 */ + I915_WRITE(MI_STATE, _MASKED_BIT_ENABLE(MI_AGPBUSY_INT_EN) | + _MASKED_BIT_DISABLE(MI_AGPBUSY_830_MODE)); } static void i830_init_clock_gating(struct drm_device *dev) -- 1.8.3.2 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx