[Intel-gfx] [PATCH] drm/i915/bdw: The TLB invalidation mechanism has been removed from INSTPM

[Chris Wilson]

On Thu, Mar 13, 2014 at 08:19:06AM -0700, Ben Widawsky wrote:
> On Thu, Mar 13, 2014 at 12:51 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > Upon resume, the hardware continues writing the breadcrumbs into the old
> > hws page (due to the stale TLB) and we try to read the seqno from the
> > new page, so as shown by the error-states it appears that the breadcrumb
> > writes are not happening. Since the hardware is writing to a random address,
> > we are now corrupting random memory.
> >
> > Which is what I thought I said in the changelog.
> 
> Yes, you did say that. However, we should be idling on freeze, so the
> explanation
> I was missing is how or why the HW is continuing to use the old status page even
> though we've had to do a TLB flush when we emit the next batch.

Different set of TLBs. This CS TLB appears to be unrelated to individual
set of cache TLBs we flush with pipecontrols or flush_dw.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre