[Intel-gfx] [PATCH] drm/i915: Invalidate TLBs for the rings after a reset

[Chris Wilson]

On Tue, Aug 06, 2013 at 07:01:14PM +0100, Chris Wilson wrote:
> After any "soft gfx reset" we must manually invalidate the TLBs
> associated with each ring. Empirically, it seems that a
> suspend/resume or D3-D0 cycle count as a "soft reset". The symptom is
> that the hardware would fail to note the new address for its status
> page, and so it would continue to write the shadow registers and
> breadcrumbs into the old physical address (now used by something
> completely different, scary). Whereas the driver would read the new
> status page and never see any progress, it would appear that the GPU
> hung immediately upon resume.
> 
> Based on a patch by naresh kumar kachhi <naresh.kumar.kacchi at intel.com>
> 
> Reported-by: Thiago Macieira <thiago at kde.org>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64725
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Thiago reports that early testing indicates success.

Anyone fancy acking this and sending this onto to stable@?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre