[Intel-gfx] [PATCH 2/2] drm/i915: gen 9 h/w w/a (WaEnableForceRestoreInCtxtDescForVCS)

[Damien Lespiau]

On Fri, Feb 06, 2015 at 11:30:04AM +0000, Nick Hoath wrote:
> Add:
> WaEnableForceRestoreInCtxtDescForVCS
> 
> v2: Add stepping check.
> 
> v3: Fixed stepping check direction. Cleaned up indentation.
> 
> Signed-off-by: Nick Hoath <nicholas.hoath at intel.com>

Reviewed-by: Damien Lespiau <damien.lespiau at intel.com>

-- 
Damien

> ---
>  drivers/gpu/drm/i915/intel_lrc.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index a94346f..cc1c1a7 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -254,8 +254,10 @@ u32 intel_execlists_ctx_id(struct drm_i915_gem_object *ctx_obj)
>  	return lrca >> 12;
>  }
>  
> -static uint64_t execlists_ctx_descriptor(struct drm_i915_gem_object *ctx_obj)
> +static uint64_t execlists_ctx_descriptor(struct intel_engine_cs *ring,
> +					 struct drm_i915_gem_object *ctx_obj)
>  {
> +	struct drm_device *dev = ring->dev;
>  	uint64_t desc;
>  	uint64_t lrca = i915_gem_obj_ggtt_offset(ctx_obj);
>  
> @@ -272,6 +274,13 @@ static uint64_t execlists_ctx_descriptor(struct drm_i915_gem_object *ctx_obj)
>  	 * signalling between Command Streamers */
>  	/* desc |= GEN8_CTX_FORCE_RESTORE; */
>  
> +	/* WaEnableForceRestoreInCtxtDescForVCS:skl */
> +	if (IS_GEN9(dev) &&
> +	    INTEL_REVID(dev) <= SKL_REVID_B0 &&
> +	    (ring->id == BCS || ring->id == VCS ||
> +	    ring->id == VECS || ring->id == VCS2))
> +		desc |= GEN8_CTX_FORCE_RESTORE;
> +
>  	return desc;
>  }
>  
> @@ -286,13 +295,13 @@ static void execlists_elsp_write(struct intel_engine_cs *ring,
>  
>  	/* XXX: You must always write both descriptors in the order below. */
>  	if (ctx_obj1)
> -		temp = execlists_ctx_descriptor(ctx_obj1);
> +		temp = execlists_ctx_descriptor(ring, ctx_obj1);
>  	else
>  		temp = 0;
>  	desc[1] = (u32)(temp >> 32);
>  	desc[0] = (u32)temp;
>  
> -	temp = execlists_ctx_descriptor(ctx_obj0);
> +	temp = execlists_ctx_descriptor(ring, ctx_obj0);
>  	desc[3] = (u32)(temp >> 32);
>  	desc[2] = (u32)temp;
>  
> -- 
> 2.1.1
>