[Intel-gfx] [PATCH 3/3] drm/i915: refactor stepping info retrieval

[Daniel Vetter]

On Tue, Oct 20, 2015 at 03:38:33PM +0300, Jani Nikula wrote:
> Have only one if ladder for platforms and only one range check for
> size. Makes it easier to handle new platforms. Remove the use of
> negative return values in char, which might underflow to be positive for
> some negative error codes.
> 
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>

On the series: Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

> ---
>  drivers/gpu/drm/i915/intel_csr.c | 46 ++++++++++++++++++++--------------------
>  1 file changed, 23 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
> index fe9a55cf8212..3e7953254803 100644
> --- a/drivers/gpu/drm/i915/intel_csr.c
> +++ b/drivers/gpu/drm/i915/intel_csr.c
> @@ -188,28 +188,25 @@ static const struct stepping_info bxt_stepping_info[] = {
>  	{'B', '0'}, {'B', '1'}, {'B', '2'}
>  };
>  
> -static char intel_get_stepping(struct drm_device *dev)
> +static const struct stepping_info *intel_get_stepping_info(struct drm_device *dev)
>  {
> -	if (IS_SKYLAKE(dev) && (dev->pdev->revision <
> -			ARRAY_SIZE(skl_stepping_info)))
> -		return skl_stepping_info[dev->pdev->revision].stepping;
> -	else if (IS_BROXTON(dev) && (dev->pdev->revision <
> -				ARRAY_SIZE(bxt_stepping_info)))
> -		return bxt_stepping_info[dev->pdev->revision].stepping;
> -	else
> -		return -ENODATA;
> -}
> +	const struct stepping_info *si;
> +	unsigned int size;
> +
> +	if (IS_SKYLAKE(dev)) {
> +		size = ARRAY_SIZE(skl_stepping_info);
> +		si = skl_stepping_info;
> +	} else if (IS_BROXTON(dev)) {
> +		size = ARRAY_SIZE(bxt_stepping_info);
> +		si = bxt_stepping_info;
> +	} else {
> +		return NULL;
> +	}
>  
> -static char intel_get_substepping(struct drm_device *dev)
> -{
> -	if (IS_SKYLAKE(dev) && (dev->pdev->revision <
> -			ARRAY_SIZE(skl_stepping_info)))
> -		return skl_stepping_info[dev->pdev->revision].substepping;
> -	else if (IS_BROXTON(dev) && (dev->pdev->revision <
> -			ARRAY_SIZE(bxt_stepping_info)))
> -		return bxt_stepping_info[dev->pdev->revision].substepping;
> -	else
> -		return -ENODATA;
> +	if (INTEL_REVID(dev) < size)
> +		return si + INTEL_REVID(dev);
> +
> +	return NULL;
>  }
>  
>  /**
> @@ -296,8 +293,8 @@ static void finish_csr_load(const struct firmware *fw, void *context)
>  	struct intel_package_header *package_header;
>  	struct intel_dmc_header *dmc_header;
>  	struct intel_csr *csr = &dev_priv->csr;
> -	char stepping = intel_get_stepping(dev);
> -	char substepping = intel_get_substepping(dev);
> +	const struct stepping_info *stepping_info = intel_get_stepping_info(dev);
> +	char stepping, substepping;
>  	uint32_t dmc_offset = CSR_DEFAULT_FW_OFFSET, readcount = 0, nbytes;
>  	uint32_t i;
>  	uint32_t *dmc_payload;
> @@ -308,11 +305,14 @@ static void finish_csr_load(const struct firmware *fw, void *context)
>  		goto out;
>  	}
>  
> -	if ((stepping == -ENODATA) || (substepping == -ENODATA)) {
> +	if (!stepping_info) {
>  		DRM_ERROR("Unknown stepping info, firmware loading failed\n");
>  		goto out;
>  	}
>  
> +	stepping = stepping_info->stepping;
> +	substepping = stepping_info->substepping;
> +
>  	/* Extract CSS Header information*/
>  	css_header = (struct intel_css_header *)fw->data;
>  	if (sizeof(struct intel_css_header) !=
> -- 
> 2.1.4
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch