[Intel-gfx] [PATCH 6/8] drm/i915: TLB invalidation with MI_FLUSH_DW requires a post-sync op

[Chris Wilson]

On Thu, 25 Oct 2012 12:15:46 -0700, Jesse Barnes <jbarnes at virtuousgeek.org> wrote:
> So store into the scratch space of the HWS to make sure the invalidate
> occurs.
> 
> v2: use GTT address space for store, clean up #defines (Chris)
> 
> Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> ---
> @@ -1460,10 +1467,17 @@ static int blt_ring_flush(struct intel_ring_buffer *ring,
>  		return ret;
>  
>  	cmd = MI_FLUSH_DW;
> +	/*
> +	 * Bspec vol 1c.3 - blitter engine command streamer:
> +	 * "If ENABLED, all TLBs will be invalidated once the flush
> +	 * operation is complete. This bit is only valid when the
> +	 * Post-Sync Operation field is a value of 1h or 3h."
> +	 */
>  	if (invalidate & I915_GEM_DOMAIN_RENDER)
> -		cmd |= MI_INVALIDATE_TLB;
> +		cmd |= MI_INVALIDATE_TLB | MI_FLUSH_DW_STORE_INDEX |
> +			MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_OP_STOREDW;
>  	intel_ring_emit(ring, cmd);
> -	intel_ring_emit(ring, 0);
> +	intel_ring_emit(ring, I915_GEM_HWS_SCRATCH_INDEX | MI_FLUSH_DW_USE_GTT);

s/SCRATCH_INDEX/SCRATCH_ADDR/
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre