[Intel-gfx] [PATCH] drm/i915/guc: Reserve the upper end of the Global GTT for the GuC

[Arkadiusz Hiler]

On Thu, Dec 22, 2016 at 03:18:08PM +0000, Chris Wilson wrote:
> On Thu, Dec 22, 2016 at 03:53:15PM +0100, Arkadiusz Hiler wrote:
> > On Wed, Dec 21, 2016 at 07:35:04PM +0100, Srivatsa, Anusha wrote:
> > > With enable_guc_loading=2 and enable_guc_submission=0 I get HuC
> > > authentication failure and with enable_guc_loading and
> > > enable_guc_submisssion both set to 2 the device does not show any
> > > display.
> > 
> > Sadly "the fix" fixes the issues we had with the loading - we can load
> > GuC but...
> > 
> > GuC Actions (INTEL_GUC_ACTION*, and intel_guc_send()) seem to care about
> > kernel context pinned location as well (not directly though). And it's
> > much more restritive.
> > 
> > Experimentally I was able to determine that if we have ctx pinned above
> > 0x10000000 (2 GB) mark, GuC Actions just fail.
> 
> Are we certain this only applies to the kernel/golden context? No other
> objects accessed by the GuC are affected?
> -Chris

Not sure yet.

> -- 
> Chris Wilson, Intel Open Source Technology Centre

-- 
Cheers,
Arek