[Intel-gfx] [PATCH 4/4] drm/i915/gen12: Invalidate aux table entries forcibly

[Chris Wilson]

Quoting Mika Kuoppala (2020-05-06 16:58:55)
> Aux table invalidation can fail on update. So
> next access may cause memory access to be into stale entry.
> 
> Proposed workaround is to invalidate entries between
> all batchbuffers.
> 
> v2: correct register address (Yang)
> 
> References bspec#43904, hsdes#1809175790
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Chuansheng Liu <chuansheng.liu at intel.com>
> Cc: Rafael Antognolli <rafael.antognolli at intel.com>
> Cc: Yang A Shi <yang.a.shi at intel.com>
> Signed-off-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>

I only hear good things about v3, so
Acked-by: Chris Wilson <chris at chris-wilson.co.uk>

> @@ -2526,6 +2526,8 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
>  #define HSW_GTT_CACHE_EN       _MMIO(0x4024)
>  #define   GTT_CACHE_EN_ALL     0xF0007FFF
>  #define GEN7_WR_WATERMARK      _MMIO(0x4028)
> +#define GEN12_GFX_CCS_AUX_NV   _MMIO(0x4208)
> +#define   AUX_INV              REG_BIT(0)
>  #define GEN7_GFX_PRIO_CTRL     _MMIO(0x402C)
>  #define ARB_MODE               _MMIO(0x4030)
>  #define   ARB_MODE_SWIZZLE_SNB (1 << 4)

4024, 4028, 4208, 402C, 4030.

Something seems not quite right.
-Chris