drm/i915/kbl: Add WaDisableDynamicCreditSharing
Bspec states that we need to turn off dynamic credit
sharing on kbl revid a0 and b0. This happens by writing bit 28
on 0x4ab8.
References: HSD#2225601, HSD#2226938, HSD#2225763
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465309159-30531-15-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit c0b730d572ea00d427f6112b17982c6b9d5e97bb)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 3e16b9d..b7cfb38 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1672,6 +1672,9 @@
#define GEN7_TLB_RD_ADDR _MMIO(0x4700)
+#define GAMT_CHKN_BIT_REG _MMIO(0x4ab8)
+#define GAMT_CHKN_DISABLE_DYNAMIC_CREDIT_SHARING (1<<28)
+
#if 0
#define PRB0_TAIL _MMIO(0x2030)
#define PRB0_HEAD _MMIO(0x2034)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 421e03d..8106a70 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1202,6 +1202,11 @@
I915_WRITE(GEN8_GARBCNTL, (I915_READ(GEN8_GARBCNTL) |
GEN9_GAPS_TSV_CREDIT_DISABLE));
+ /* WaDisableDynamicCreditSharing:kbl */
+ if (IS_KBL_REVID(dev_priv, 0, KBL_REVID_B0))
+ WA_SET_BIT(GAMT_CHKN_BIT_REG,
+ GAMT_CHKN_DISABLE_DYNAMIC_CREDIT_SHARING);
+
/* WaDisableFenceDestinationToSLM:kbl (pre-prod) */
if (IS_KBL_REVID(dev_priv, KBL_REVID_A0, KBL_REVID_A0))
WA_SET_BIT_MASKED(HDC_CHICKEN0,
