[Intel-gfx] [PATCH 2/2] drm/i915/get_params: Add HuC status to getparams

[Tvrtko Ursulin]

On 16/08/16 12:18, Peter Antoine wrote:
> This patch will allow for getparams to return the status of the HuC.
> As the HuC has to be validated by the GuC this patch uses the validated
> status to show when the HuC is loaded and ready for use. You cannot use
> the loaded status as with the GuC as the HuC is verified after it is
> loaded and is not usable until it is verified.
>
> Signed-off-by: Peter Antoine <peter.antoine at intel.com>
> ---
>   drivers/gpu/drm/i915/i915_drv.c         |  4 ++++
>   drivers/gpu/drm/i915/intel_huc.h        |  2 +-
>   drivers/gpu/drm/i915/intel_huc_loader.c | 21 +++++++++++++++++++++
>   include/uapi/drm/i915_drm.h             |  1 +
>   4 files changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index c8fc3d0..909297e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -49,6 +49,7 @@
>   #include "i915_trace.h"
>   #include "i915_vgpu.h"
>   #include "intel_drv.h"
> +#include "intel_huc.h"
>   #include "intel_guc.h"
>
>   static struct drm_driver driver;
> @@ -355,6 +356,9 @@ static int i915_getparam(struct drm_device *dev, void *data,
>   	case I915_PARAM_MIN_EU_IN_POOL:
>   		value = INTEL_INFO(dev)->min_eu_in_pool;
>   		break;
> +	case I915_PARAM_HAS_HUC:
> +		value = intel_is_huc_valid(dev);
> +		break;
>   	case I915_PARAM_HAS_GUC:
>   		value = intel_is_guc_valid(dev);
>   		break;
> diff --git a/drivers/gpu/drm/i915/intel_huc.h b/drivers/gpu/drm/i915/intel_huc.h
> index 946caa7..8c1847a 100644
> --- a/drivers/gpu/drm/i915/intel_huc.h
> +++ b/drivers/gpu/drm/i915/intel_huc.h
> @@ -40,5 +40,5 @@ extern void intel_huc_init(struct drm_device *dev);
>   extern int intel_huc_load(struct drm_device *dev);
>   extern void intel_huc_auth(struct drm_device *dev);
>   extern void intel_huc_fini(struct drm_device *dev);
> -
> +extern int intel_is_huc_valid(struct drm_device *dev);
>   #endif
> diff --git a/drivers/gpu/drm/i915/intel_huc_loader.c b/drivers/gpu/drm/i915/intel_huc_loader.c
> index 87a6948..ee42d5e 100644
> --- a/drivers/gpu/drm/i915/intel_huc_loader.c
> +++ b/drivers/gpu/drm/i915/intel_huc_loader.c
> @@ -273,3 +273,24 @@ void intel_huc_fini(struct drm_device *dev)
>
>   	huc_fw->fetch_status = UC_FIRMWARE_NONE;
>   }
> +
> +/**
> + * intel_is_huc_valid() - Check to see if the HuC is fully loaded.
> + * @dev:	drm dedvice to check.
> + *
> + * This function will return true if the guc has been loaded and
> + * has valid firmware. The simplest way of doing this is to check
> + * if the HuC has been validated, if so it must have been loaded.
> + */
> +int intel_is_huc_valid(struct drm_device *dev)
> +{
> +	int result;
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +
> +	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
> +	result = ((I915_READ(HUC_STATUS2) & HUC_FW_VERIFIED) != 0);
> +	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);

Is there a special reason why it is required to grab all forcewakes?

HUC_STATUS2 is 0xd3b0 which appears to be in the media forcewake range 
already defined for gen9. So I915_READ will already grab that one.

Regards,

Tvrtko