drm/i915/gen9: Add WaFlushCoherentL3CacheLinesAtContextSwitch workaround

In Indirect context w/a batch buffer,
+WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt

v2: address static checker warning where unsigned value was checked for
less than zero which is never true (Dan Carpenter).

v3: The WA uses default value of GEN8_L3SQCREG4 during flush but that disables
some other WA; update default value to retain it and document dependency (Mika).

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Arun Siluvery 2015-07-14 15:01:29 +01:00 committed by Daniel Vetter
parent 0907c8f7e0
commit a4106a782d
2 changed files with 19 additions and 0 deletions

View File

@ -1097,6 +1097,15 @@ static inline int gen8_emit_flush_coherentl3_wa(struct intel_engine_cs *ring,
{
uint32_t l3sqc4_flush = (0x40400000 | GEN8_LQSC_FLUSH_COHERENT_LINES);
/*
* WaDisableLSQCROPERFforOCL:skl
* This WA is implemented in skl_init_clock_gating() but since
* this batch updates GEN8_L3SQCREG4 with default value we need to
* set this bit here to retain the WA during flush.
*/
if (IS_SKYLAKE(ring->dev) && INTEL_REVID(ring->dev) <= SKL_REVID_E0)
l3sqc4_flush |= GEN8_LQSC_RO_PERF_DIS;
wa_ctx_emit(batch, index, (MI_STORE_REGISTER_MEM_GEN8(1) |
MI_SRM_LRM_GLOBAL_GTT));
wa_ctx_emit(batch, index, GEN8_L3SQCREG4);
@ -1253,6 +1262,7 @@ static int gen9_init_indirectctx_bb(struct intel_engine_cs *ring,
uint32_t *const batch,
uint32_t *offset)
{
int ret;
struct drm_device *dev = ring->dev;
uint32_t index = wa_ctx_start(wa_ctx, *offset, CACHELINE_DWORDS);
@ -1261,6 +1271,12 @@ static int gen9_init_indirectctx_bb(struct intel_engine_cs *ring,
(IS_BROXTON(dev) && (INTEL_REVID(dev) == BXT_REVID_A0)))
wa_ctx_emit(batch, index, MI_ARB_ON_OFF | MI_ARB_DISABLE);
/* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt */
ret = gen8_emit_flush_coherentl3_wa(ring, batch, index);
if (ret < 0)
return ret;
index = ret;
/* Pad to end of cacheline */
while (index % CACHELINE_DWORDS)
wa_ctx_emit(batch, index, MI_NOOP);

View File

@ -95,6 +95,9 @@ static void skl_init_clock_gating(struct drm_device *dev)
_MASKED_BIT_ENABLE(GEN9_TSG_BARRIER_ACK_DISABLE));
}
/* GEN8_L3SQCREG4 has a dependency with WA batch so any new changes
* involving this register should also be added to WA batch as required.
*/
if (INTEL_REVID(dev) <= SKL_REVID_E0)
/* WaDisableLSQCROPERFforOCL:skl */
I915_WRITE(GEN8_L3SQCREG4, I915_READ(GEN8_L3SQCREG4) |