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

[Arkadiusz Hiler]

On Thu, Dec 08, 2016 at 11:55:34PM +0000, Chris Wilson wrote:
> 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?

Just confirmed that this register indeed requires MEDIA FW.

> -Chris

-- 
Cheers,
Arek