[Intel-gfx] [PATCH 2/2] drm/i915: Reorder media/render reset on g4x

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> Ville found a reference to WaMediaResetBeforeFullReset which we presume
> means that we should simply do the media reset first.

Yesterday I reordered the resets but I recall it didnt help.
I will retry but regardless yeah resetting media first makes
sense.

>
> References: https://bugs.freedesktop.org/show_bug.cgi?id=100942
> Suggested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Mika Kuoppala <mika.kuoppala at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_uncore.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
> index fc3da0a6fdbb..c3d0d81b50e4 100644
> --- a/drivers/gpu/drm/i915/intel_uncore.c
> +++ b/drivers/gpu/drm/i915/intel_uncore.c
> @@ -1504,12 +1504,6 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv, unsigned engine_mask)
>  	struct pci_dev *pdev = dev_priv->drm.pdev;
>  	int ret;
>  
> -	pci_write_config_byte(pdev, I915_GDRST,
> -			      GRDOM_RENDER | GRDOM_RESET_ENABLE);
> -	ret =  wait_for(g4x_reset_complete(pdev), 500);
> -	if (ret)
> -		goto out;
> -
>  	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
>  	I915_WRITE(VDECCLK_GATE_D, I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
>  	POSTING_READ(VDECCLK_GATE_D);
> @@ -1517,11 +1511,17 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv, unsigned engine_mask)
>  	pci_write_config_byte(pdev, I915_GDRST,
>  			      GRDOM_MEDIA | GRDOM_RESET_ENABLE);
>  	ret =  wait_for(g4x_reset_complete(pdev), 500);
> +	if (ret)
> +		goto out;
>

We should restore the WaVcp... state if we fail. Not that it
was right to begin with.

-Mika

>  	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
>  	I915_WRITE(VDECCLK_GATE_D, I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
>  	POSTING_READ(VDECCLK_GATE_D);
>  
> +	pci_write_config_byte(pdev, I915_GDRST,
> +			      GRDOM_RENDER | GRDOM_RESET_ENABLE);
> +	ret =  wait_for(g4x_reset_complete(pdev), 500);
> +
>  out:
>  	pci_write_config_byte(pdev, I915_GDRST, 0);
>  	return ret;
> -- 
> 2.11.0