[Intel-gfx] [PATCH 01/10] drm/i915: No LLC_MLC for HSW.

[Jesse Barnes]

On Mon, 22 Oct 2012 18:34:06 -0700
Ben Widawsky <ben at bwidawsk.net> wrote:

> The mid-level cache or as it's more commonly referred to now as L3, is
> not setup this way on HSW.
> 
> Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_gem_gtt.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index 47e427e..5751ad2 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -218,7 +218,11 @@ void i915_ppgtt_bind_object(struct i915_hw_ppgtt *ppgtt,
>  
>  	switch (cache_level) {
>  	case I915_CACHE_LLC_MLC:
> -		pte_flags |= GEN6_PTE_CACHE_LLC_MLC;
> +		/* Haswell doesn't set L3 this way */
> +		if (IS_HASWELL(obj->base.dev))
> +			pte_flags |= GEN6_PTE_CACHE_LLC;
> +		else
> +			pte_flags |= GEN6_PTE_CACHE_LLC_MLC;
>  		break;
>  	case I915_CACHE_LLC:
>  		pte_flags |= GEN6_PTE_CACHE_LLC;
> @@ -253,12 +257,12 @@ static unsigned int cache_level_to_agp_type(struct drm_device *dev,
>  {
>  	switch (cache_level) {
>  	case I915_CACHE_LLC_MLC:
> -		if (INTEL_INFO(dev)->gen >= 6)
> -			return AGP_USER_CACHED_MEMORY_LLC_MLC;
>  		/* Older chipsets do not have this extra level of CPU
>  		 * cacheing, so fallthrough and request the PTE simply
>  		 * as cached.
>  		 */
> +		if (INTEL_INFO(dev)->gen >= 6 && !IS_HASWELL(dev))
> +			return AGP_USER_CACHED_MEMORY_LLC_MLC;
>  	case I915_CACHE_LLC:
>  		return AGP_USER_CACHED_MEMORY;
>  	default:

We might want a .has_mlc or something here at some point, but that
doesn't have to happen here.

Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>

-- 
Jesse Barnes, Intel Open Source Technology Center