@@ -2815,6 +2815,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define VLV_GU_CTL0 _MMIO(VLV_DISPLAY_BASE + 0x2030)
#define VLV_GU_CTL1 _MMIO(VLV_DISPLAY_BASE + 0x2034)
#define SCPD0 _MMIO(0x209c) /* 915+ only */
+#define SCPD_FBC_IGNORE_3D (1 << 6)
#define CSTATE_RENDER_CLOCK_GATE_DISABLE (1 << 5)
#define GEN2_IER _MMIO(0x20a0)
#define GEN2_IIR _MMIO(0x20a4)
@@ -7369,6 +7369,16 @@ static void i85x_init_clock_gating(struct drm_i915_private *dev_priv)
I915_WRITE(MEM_MODE,
_MASKED_BIT_ENABLE(MEM_DISPLAY_TRICKLE_FEED_DISABLE));
+
+ /*
+ * Have FBC ignore 3D activity since we use software
+ * render tracking, and otherwise a pure 3D workload
+ * (even if it just renders a single frame and then does
+ * abosultely nothing) would not allow FBC to recompress
+ * until a 2D blit occurs.
+ */
+ I915_WRITE(SCPD0,
+ _MASKED_BIT_ENABLE(SCPD_FBC_IGNORE_3D));
}
static void i830_init_clock_gating(struct drm_i915_private *dev_priv)