[Intel-gfx] [PATCH 21/39] drm/i915/guc: Disable global reset

[Chris Wilson]

Quoting Daniele Ceraolo Spurio (2019-01-07 21:28:48)
> 
> On 01/07/2019 10:50 AM, Chris Wilson wrote:
> > Quoting Daniele Ceraolo Spurio (2019-01-07 18:31:52)
> >>
> >> Were you already
> >> planning/working on something along the lines of the possible solution
> >> mentioned in the commit message? Just trying to understand what the
> >> status is before jumping in to avoid duplication of work ;)
> > 
> > The compromises required (reserving space for the firmware) seem like it
> > will just end up with a lot of screaming to make it mutexless today.
> 
> Aren't we already keeping some GuC stuff perma-pinned (e.g. the 
> stage_desc_pool)? Current Gen11+ firmware needs more space and uses 
> objects up to tens of MBs, the blobs aren't that big in comparison.

Hmm, there's always the guc reserved region (top/bottom). Is that large
enough to store the firmware, and would it be legal to load from those
addresses? (After the dma transfer we wouldn't use those ourselves, so
the guc is free to utilise them for its scratch. Then after the guc is
reset, we would put the firmware there again for dma xfer).
-Chris