They don't fix our problems alone, but we're told to set them.
Signed-off-by: Eric Anholt <eric at anholt.net>
---
I think this is -next material, since it's not clearly fixing a bug.
drivers/gpu/drm/i915/i915_reg.h | 4 ++++
drivers/gpu/drm/i915/intel_display.c | 4 ++++
2 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 9d15474..9a97535 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2883,6 +2883,10 @@
#define ILK_DPFC_DIS1 (1<<8)
#define ILK_DPFC_DIS2 (1<<9)
+#define IVB_CHICKEN3 0x4200c
+# define CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE (1 << 5)
+# define CHICKEN3_DGMG_DONE_FIX_DISABLE (1 << 2)
+
#define DISP_ARB_CTL 0x45000
#define DISP_TILE_SURFACE_SWIZZLING (1<<13)
#define DISP_FBC_WM_DIS (1<<15)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8a61b81..1fe0c67 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8252,6 +8252,10 @@ static void ivybridge_init_clock_gating(struct drm_device *dev)
I915_WRITE(ILK_DSPCLK_GATE, IVB_VRHUNIT_CLK_GATE);
+ I915_WRITE(IVB_CHICKEN3,
+ CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
+ CHICKEN3_DGMG_DONE_FIX_DISABLE);
+
for_each_pipe(pipe) {
I915_WRITE(DSPCNTR(pipe),
I915_READ(DSPCNTR(pipe)) |
--
1.7.7.3
