[Intel-gfx] [PATCH 08/10] drm/i915/uc: Simplify firmware path handling

[Michal Wajdeczko]

On Fri, Feb 24, 2017 at 04:40:02PM +0100, Arkadiusz Hiler wrote:
> Currently fw->path values can represent one of three possible states:
> 
>  1) NULL - device without the uC
>  2) '\0' - device with the uC but have no firmware
>  3) else - device with the uC and we have firmware
> 
> Second case is used only to WARN at a later stage.
> 
> We can WARN right away and merge cases 1 and 2.
> 
> Code can be even further simplified and common (HuC/GuC logic) happening
> right before the fetch can be offloaded to the common function.
> 
> v2: fewer temporary variables, more straightforward flow (M. Wajdeczko)
> v3: DRM_ERROR instead of WARN (M. Wajdeczko)
> v4: coding standard (J. Lahtinen)
> 
> Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Michal Winiarski <michal.winiarski at intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Signed-off-by: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_guc_loader.c | 39 +++++++++++----------------------
>  drivers/gpu/drm/i915/intel_huc.c        | 20 +++++------------
>  drivers/gpu/drm/i915/intel_uc.c         |  4 +++-
>  3 files changed, 22 insertions(+), 41 deletions(-)
> 

<snip>

> @@ -483,39 +478,31 @@ int intel_guc_init_hw(struct drm_i915_private *dev_priv)
>  void intel_guc_init_fw(struct intel_guc *guc)
>  {
>  	struct drm_i915_private *dev_priv = guc_to_i915(guc);
> -	const char *fw_path;
>  
> -	if (!HAS_GUC_UCODE(dev_priv)) {
> -		fw_path = NULL;
> -	} else if (IS_SKYLAKE(dev_priv)) {
> -		fw_path = I915_SKL_GUC_UCODE;
> +	guc->fw.path = NULL;
> +	guc->fw.fetch_status = INTEL_UC_FIRMWARE_NONE;
> +	guc->fw.load_status = INTEL_UC_FIRMWARE_NONE;
> +	guc->fw.fw = INTEL_UC_FW_TYPE_GUC;
> +
> +	if (IS_SKYLAKE(dev_priv)) {
> +		guc->fw.path = I915_SKL_GUC_UCODE;
>  		guc->fw.major_ver_wanted = SKL_FW_MAJOR;
>  		guc->fw.minor_ver_wanted = SKL_FW_MINOR;
>  	} else if (IS_BROXTON(dev_priv)) {
> -		fw_path = I915_BXT_GUC_UCODE;
> +		guc->fw.path = I915_BXT_GUC_UCODE;
>  		guc->fw.major_ver_wanted = BXT_FW_MAJOR;
>  		guc->fw.minor_ver_wanted = BXT_FW_MINOR;
>  	} else if (IS_KABYLAKE(dev_priv)) {
> -		fw_path = I915_KBL_GUC_UCODE;
> +		guc->fw.path = I915_KBL_GUC_UCODE;
>  		guc->fw.major_ver_wanted = KBL_FW_MAJOR;
>  		guc->fw.minor_ver_wanted = KBL_FW_MINOR;
>  	} else {
> -		fw_path = "";	/* unknown device */
> +		DRM_ERROR("No GuC firmware known for platform with GuC!\n");
> +		i915.enable_guc_loading = 0;

Hmm, I don't like that we're modifying param outside of intel_uc_sanitize_options()
If we split this function into fw filename selection and actual prepare/fetch then
we could do this fw initial sanitization in proper place as:

	i915.enable_guc_loading = intel_sanitize_guc_fw(dev_priv);


> +		return;
>  	}
>  
> -	guc->fw.path = fw_path;
> -	guc->fw.fetch_status = INTEL_UC_FIRMWARE_NONE;
> -	guc->fw.load_status = INTEL_UC_FIRMWARE_NONE;
> -
> -	if (fw_path == NULL)
> -		return;
> -	if (*fw_path == '\0')
> -		return;
> -
> -	guc->fw.fetch_status = INTEL_UC_FIRMWARE_PENDING;
> -	DRM_DEBUG_DRIVER("GuC firmware pending, path %s\n", fw_path);
>  	intel_uc_prepare_fw(dev_priv, &guc->fw);
> -	/* status must now be FAIL or SUCCESS */
>  }
>  
>  /**
> diff --git a/drivers/gpu/drm/i915/intel_huc.c b/drivers/gpu/drm/i915/intel_huc.c
> index 6f0811c..757f618 100644
> --- a/drivers/gpu/drm/i915/intel_huc.c
> +++ b/drivers/gpu/drm/i915/intel_huc.c
> @@ -155,37 +155,29 @@ static int huc_ucode_xfer(struct drm_i915_private *dev_priv)
>  void intel_huc_init_fw(struct intel_huc *huc)
>  {
>  	struct drm_i915_private *dev_priv = huc_to_i915(huc);
> -	const char *fw_path = NULL;
>  
>  	huc->fw.path = NULL;
>  	huc->fw.fetch_status = INTEL_UC_FIRMWARE_NONE;
>  	huc->fw.load_status = INTEL_UC_FIRMWARE_NONE;
>  	huc->fw.fw = INTEL_UC_FW_TYPE_HUC;
>  
> -	if (!HAS_HUC_UCODE(dev_priv))
> -		return;
> -
>  	if (IS_SKYLAKE(dev_priv)) {
> -		fw_path = I915_SKL_HUC_UCODE;
> +		huc->fw.path = I915_SKL_HUC_UCODE;
>  		huc->fw.major_ver_wanted = SKL_HUC_FW_MAJOR;
>  		huc->fw.minor_ver_wanted = SKL_HUC_FW_MINOR;
>  	} else if (IS_BROXTON(dev_priv)) {
> -		fw_path = I915_BXT_HUC_UCODE;
> +		huc->fw.path = I915_BXT_HUC_UCODE;
>  		huc->fw.major_ver_wanted = BXT_HUC_FW_MAJOR;
>  		huc->fw.minor_ver_wanted = BXT_HUC_FW_MINOR;
>  	} else if (IS_KABYLAKE(dev_priv)) {
> -		fw_path = I915_KBL_HUC_UCODE;
> +		huc->fw.path = I915_KBL_HUC_UCODE;
>  		huc->fw.major_ver_wanted = KBL_HUC_FW_MAJOR;
>  		huc->fw.minor_ver_wanted = KBL_HUC_FW_MINOR;
> +	} else {
> +		DRM_ERROR("No HuC firmware known for platform with HuC!\n");
> +		return;
>  	}
>  
> -	huc->fw.path = fw_path;
> -	huc->fw.fetch_status = INTEL_UC_FIRMWARE_PENDING;
> -
> -	DRM_DEBUG_DRIVER("HuC firmware pending, path %s\n", fw_path);
> -
> -	WARN(huc->fw.path == NULL, "HuC present but no fw path\n");
> -
>  	intel_uc_prepare_fw(dev_priv, &huc->fw);
>  }
>  
> diff --git a/drivers/gpu/drm/i915/intel_uc.c b/drivers/gpu/drm/i915/intel_uc.c
> index 709f964..ac9ad59 100644
> --- a/drivers/gpu/drm/i915/intel_uc.c
> +++ b/drivers/gpu/drm/i915/intel_uc.c
> @@ -267,8 +267,10 @@ void intel_uc_prepare_fw(struct drm_i915_private *dev_priv,
>  	size_t size;
>  	int err;
>  
> +	uc_fw->fetch_status = INTEL_UC_FIRMWARE_PENDING;
> +
>  	DRM_DEBUG_DRIVER("before requesting firmware: uC fw fetch status %s\n",
> -		intel_uc_fw_status_repr(uc_fw->fetch_status));
> +			 intel_uc_fw_status_repr(uc_fw->fetch_status));
>  
>  	err = request_firmware(&fw, uc_fw->path, &pdev->dev);
>  	if (err)


I think previous patches will look simpler if you start with this patch earlier.
This move will also address some previously posted comments.

-Michal