[Intel-gfx] [PATCH 8/8] drm/i915/get_params: Add HuC status to getparams

[Chris Wilson]

On Thu, Dec 08, 2016 at 03:02:19PM -0800, anushasr wrote:
> From: Peter Antoine <peter.antoine at intel.com>
> 
> 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.
> 
> v2: removed the forewakes as the registers are already force-woken.
>      (T.Ursulin)
> v4: rebased.
> v5: rebased on top of drm-tip.
> v6: rebased. Removed any reference to intel_huc.h
> 
> Signed-off-by: Peter Antoine <peter.antoine at intel.com>
> Reviewed-by: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c         |  4 ++++
>  drivers/gpu/drm/i915/intel_huc_loader.c | 12 ++++++++++++
>  drivers/gpu/drm/i915/intel_uc.h         |  1 +
>  include/uapi/drm/i915_drm.h             |  1 +
>  4 files changed, 18 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 85a47c2..6be06a27 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_uc.h"
>  
>  static struct drm_driver driver;
>  
> @@ -349,6 +350,9 @@ static int i915_getparam(struct drm_device *dev, void *data,
>  		 */
>  		value = 1;
>  		break;
> +	case I915_PARAM_HAS_HUC:
> +		value = intel_is_huc_valid(dev_priv);
> +		break;

Why did you put it here? It breaks the pattern of case statements.

>  	default:
>  		DRM_DEBUG("Unknown parameter %d\n", param->param);
>  		return -EINVAL;
> diff --git a/drivers/gpu/drm/i915/intel_huc_loader.c b/drivers/gpu/drm/i915/intel_huc_loader.c
> index 96fc727..6704cc8 100644
> --- a/drivers/gpu/drm/i915/intel_huc_loader.c
> +++ b/drivers/gpu/drm/i915/intel_huc_loader.c
> @@ -289,3 +289,15 @@ 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_priv:	drm device 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_i915_private *dev_priv)

bool

> +{
> +	return ((I915_READ(HUC_STATUS2) & HUC_FW_VERIFIED) != 0);

(brackets (because (brackets)))

But what I really wanted to ask... Does this register access require the
device to be awake and powered?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre