[Intel-gfx] [PATCH] drm/i915/tgl: Implement Wa_1606931601

[Anusha Srivatsa]

Disable Early Read and Src Swap (bit 14) by setting the chicken
register.

BSpec: 46045,52890

v2: Follow the Bspec implementation for the WA.
v3: Have 2 separate defines for bit 14 and 15.
- Rename register definitions with TGL_ prefix
v4: Bspec changed. Again. Add WA to rcs_ WA list.

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
Reviewed-by: Matt Atwood <matthew.s.atwood at intel.com>
---
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++
 drivers/gpu/drm/i915/i915_reg.h             | 1 +
 2 files changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 61106129287f..310f8e1beaab 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -1326,6 +1326,12 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
 {
 	struct drm_i915_private *i915 = engine->i915;
 
+	if (IS_TGL_REVID(i915, TGL_REVID_A0, REVID_FOREVER)) {
+		/* Wa_1606931601:tgl */
+		wa_write_or(wal,
+			    GEN7_ROW_CHICKEN2,
+			    GEN12_EARLY_READ_SRC0_DISABLE);
+	}
 	if (IS_TGL_REVID(i915, TGL_REVID_A0, TGL_REVID_A0)) {
 		/* Wa_1606700617:tgl */
 		wa_masked_en(wal,
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 0bd431f6a011..c46bec8ebd17 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -9151,6 +9151,7 @@ enum {
 #define   DOP_CLOCK_GATING_DISABLE	(1 << 0)
 #define   PUSH_CONSTANT_DEREF_DISABLE	(1 << 8)
 #define   GEN11_TDL_CLOCK_GATING_FIX_DISABLE	(1 << 1)
+#define   GEN12_EARLY_READ_SRC0_DISABLE		(1 << 14)
 
 #define HSW_ROW_CHICKEN3		_MMIO(0xe49c)
 #define  HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE    (1 << 6)
-- 
2.25.0