[Intel-gfx] [PATCH 12/22] drm/i915/icl: WaAllowUmdWriteTRTTRootTable

[Oscar Mateo]

Required for TR-TT (Tiled Resource Translation Table) support.

Do Linux UMDs make use of this? This change has been security
reviewed and the whitelisting approved. Virtualization of other
OSes could certainly use it.

v2: For whatever reason, this ended up in KBL (??!!)

Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h        | 3 +++
 drivers/gpu/drm/i915/intel_engine_cs.c | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 004a4db..04f2dd5 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -8219,6 +8219,9 @@ enum {
 #define GAMW_ECO_DEV_RW_IA_REG			_MMIO(0x4080)
 #define   GAMW_ECO_DEV_CTX_RELOAD_DISABLE	(1 << 7)
 
+#define TR_VA_TTL3_PTR_DW0		_MMIO(0x4DE0)
+#define TR_VA_TTL3_PTR_DW1		_MMIO(0x4DE4)
+
 /* IVYBRIDGE DPF */
 #define GEN7_L3CDERRST1(slice)		_MMIO(0xB008 + (slice) * 0x200) /* L3CD Error Status 1 */
 #define   GEN7_L3CDERRST1_ROW_MASK	(0x7ff<<14)
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index 7fb7283..9400f4f 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1510,6 +1510,14 @@ static int icl_init_workarounds(struct intel_engine_cs *engine)
 	if (ret)
 		return ret;
 
+	/* WaAllowUmdWriteTRTTRootTable:icl */
+	ret = wa_ring_whitelist_reg(engine, TR_VA_TTL3_PTR_DW0);
+	if (ret)
+		return ret;
+	ret = wa_ring_whitelist_reg(engine, TR_VA_TTL3_PTR_DW1);
+	if (ret)
+		return ret;
+
 	return 0;
 }
 
-- 
1.9.1