drm/i915: gen7: Disable the RHWO optimization as it can cause GPU hangs.
The BSpec Workarounds page states that bits 10 and 26 must be set to
avoid 3D ring hangs.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41353
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44610
Tested-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 4e1ee90..03c53fc 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3029,6 +3029,9 @@
#define DISP_FBC_WM_DIS (1<<15)
/* GEN7 chicken */
+#define GEN7_COMMON_SLICE_CHICKEN1 0x7010
+# define GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC ((1<<10) | (1<<26))
+
#define GEN7_L3CNTLREG1 0xB01C
#define GEN7_WA_FOR_GEN7_L3_CONTROL 0x3C4FFF8C
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a527615..d9b042b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8472,6 +8472,10 @@
CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
CHICKEN3_DGMG_DONE_FIX_DISABLE);
+ /* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
+ I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
+ GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
+
/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
I915_WRITE(GEN7_L3CNTLREG1,
GEN7_WA_FOR_GEN7_L3_CONTROL);