[Intel-gfx] [linux-gfx] [PATCH] drm/i915/pvc: Implement recommended caching policy

[Matt Roper]

On Wed, Nov 30, 2022 at 09:07:23AM -0800, Wayne Boyer wrote:
> As per the performance tuning guide, set the HOSTCACHEEN bit to
> implement the recommended caching policy on PVC.
> 
> Signed-off-by: Wayne Boyer <wayne.boyer at intel.com>

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

> ---
>  drivers/gpu/drm/i915/gt/intel_gt_regs.h     | 1 +
>  drivers/gpu/drm/i915/gt/intel_workarounds.c | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> index 784152548472..f96570995cfc 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> @@ -973,6 +973,7 @@
>  #define   GEN7_L3AGDIS				(1 << 19)
>  
>  #define XEHPC_LNCFMISCCFGREG0			_MMIO(0xb01c)
> +#define   XEHPC_HOSTCACHEEN			REG_BIT(1)
>  #define   XEHPC_OVRLSCCC			REG_BIT(0)
>  
>  #define GEN7_L3CNTLREG2				_MMIO(0xb020)
> diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
> index 1b0e40e68a9d..35e3f43e8b06 100644
> --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
> +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
> @@ -2903,6 +2903,7 @@ add_render_compute_tuning_settings(struct drm_i915_private *i915,
>  	if (IS_PONTEVECCHIO(i915)) {
>  		wa_write(wal, XEHPC_L3SCRUB,
>  			 SCRUB_CL_DWNGRADE_SHARED | SCRUB_RATE_4B_PER_CLK);
> +		wa_masked_en(wal, XEHPC_LNCFMISCCFGREG0, XEHPC_HOSTCACHEEN);
>  	}
>  
>  	if (IS_DG2(i915)) {
> -- 
> 2.37.3
> 

-- 
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation