[Intel-gfx] [PATCH] drm/i915/guc: Propagate the fw xfer timeout

[Daniele Ceraolo Spurio]

On 17/10/18 13:29, Chris Wilson wrote:
> Propagate the timeout on transferring the fw back to the caller where it
> may act upon it, usually by restarting the xfer before failing.
> 

Did you see any case where we failed the xfer and didn't get a timeout 
out of guc_wait_ucode? that'd be quite weird

Anyway, definitely better and cleaner than before:
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>

small nitpick below

> Testcase: igt/drv_selftest/live_hangcheck
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> ---
>   drivers/gpu/drm/i915/intel_guc_fw.c | 23 ++++++-----------------
>   1 file changed, 6 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_guc_fw.c b/drivers/gpu/drm/i915/intel_guc_fw.c
> index a9e6fcce467c..b68a05892dab 100644
> --- a/drivers/gpu/drm/i915/intel_guc_fw.c
> +++ b/drivers/gpu/drm/i915/intel_guc_fw.c
> @@ -125,22 +125,17 @@ static void guc_prepare_xfer(struct intel_guc *guc)
>   }
>   
>   /* Copy RSA signature from the fw image to HW for verification */
> -static int guc_xfer_rsa(struct intel_guc *guc, struct i915_vma *vma)
> +static void guc_xfer_rsa(struct intel_guc *guc, struct i915_vma *vma)
>   {
>   	struct drm_i915_private *dev_priv = guc_to_i915(guc);
> -	struct intel_uc_fw *guc_fw = &guc->fw;
> -	struct sg_table *sg = vma->pages;
>   	u32 rsa[UOS_RSA_SCRATCH_COUNT];
>   	int i;
>   
> -	if (sg_pcopy_to_buffer(sg->sgl, sg->nents, rsa, sizeof(rsa),
> -			       guc_fw->rsa_offset) != sizeof(rsa))
> -		return -EINVAL;
> +	sg_pcopy_to_buffer(vma->pages->sgl, vma->pages->nents,
> +			   rsa, sizeof(rsa), guc->fw.rsa_offset);
>   
>   	for (i = 0; i < UOS_RSA_SCRATCH_COUNT; i++)
>   		I915_WRITE(UOS_RSA_SCRATCH(i), rsa[i]);
> -
> -	return 0;
>   }
>   
>   /*
> @@ -251,17 +246,11 @@ static int guc_fw_xfer(struct intel_uc_fw *guc_fw, struct i915_vma *vma)
>   	 * by the DMA engine in one operation, whereas the RSA signature is
>   	 * loaded via MMIO.
>   	 */
> -	ret = guc_xfer_rsa(guc, vma);
> -	if (ret)
> -		DRM_WARN("GuC firmware signature xfer error %d\n", ret);
> +	guc_xfer_rsa(guc, vma);
>   
>   	ret = guc_xfer_ucode(guc, vma);
> -	if (ret)
> -		DRM_WARN("GuC firmware code xfer error %d\n", ret);
> -
> -	ret = guc_wait_ucode(guc);
> -	if (ret)
> -		DRM_ERROR("GuC firmware xfer error %d\n", ret);

With the logs gone we don't have any more error message to understand 
where exactly we hit issue (xfer vs wait_ucode). We do have debug logs 
printing the status that would give the info, but might be worth 
retaining at least 1 error-level log.

Daniele

> +	if (ret == 0)
> +		ret = guc_wait_ucode(guc);
>   
>   	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
>   
>