[Intel-gfx] [PATCH] drm/i915/cnl: WaPushConstantDereferenceHoldDisable

[Oscar Mateo]

Oops... forgot to add v2 tag. Hang on a second.


On 08/23/2017 12:53 PM, Oscar Mateo wrote:
> CS sometimes hangs on 3D Push Constant dispatches with the new
> deref enhancement logic in CNL.
>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Signed-off-by: Oscar Mateo <oscar.mateo at intel.com>
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
>   drivers/gpu/drm/i915/i915_reg.h        | 1 +
>   drivers/gpu/drm/i915/intel_engine_cs.c | 3 +++
>   2 files changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index d4ecb19..d9b0249 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -8055,6 +8055,7 @@ enum {
>   #define GEN7_ROW_CHICKEN2		_MMIO(0xe4f4)
>   #define GEN7_ROW_CHICKEN2_GT2		_MMIO(0xf4f4)
>   #define   DOP_CLOCK_GATING_DISABLE	(1<<0)
> +#define   PUSH_CONSTANT_DEREF_DISABLE	(1<<8)
>   
>   #define HSW_ROW_CHICKEN3		_MMIO(0xe49c)
>   #define  HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE    (1 << 6)
> diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
> index d23f188..d7e1ccf 100644
> --- a/drivers/gpu/drm/i915/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/intel_engine_cs.c
> @@ -1083,6 +1083,9 @@ static int cnl_init_workarounds(struct intel_engine_cs *engine)
>   	WA_SET_BIT(GEN9_GAMT_ECO_REG_RW_IA,
>   		   GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
>   
> +	/* WaPushConstantDereferenceHoldDisable:cnl */
> +	WA_SET_BIT(GEN7_ROW_CHICKEN2, PUSH_CONSTANT_DEREF_DISABLE);
> +
>   	/* WaEnablePreemptionGranularityControlByUMD:cnl */
>   	ret= wa_ring_whitelist_reg(engine, GEN8_CS_CHICKEN1);
>   	if (ret)