[Intel-gfx] [PATCH] drm/i915: SNB BLT workaround

[Chris Wilson]

On Tue, 2 Nov 2010 17:08:09 +0800, "Zou, Nanhai" <nanhai.zou at intel.com> wrote:
> >>-----Original Message-----
> >>From: Chris Wilson [mailto:chris at chris-wilson.co.uk]
> >>Sent: 2010年11月2日 17:05
> >>To: Zou, Nanhai; intel-gfx at lists.freedesktop.org
> >>Cc: Zou, Nanhai
> >>Subject: Re: [PATCH] drm/i915: SNB BLT workaround
> >>
> >>On Tue,  2 Nov 2010 16:31:01 +0800, Zou Nan hai <nanhai.zou at intel.com> wrote:
> >>> 	on some stepping of SNB cpu, the first command to be parsed in BLT
> >>> 	command streamer should be MI_BATCHBUFFER_START
> >>> 	otherwise the GPU may hang.
> >>
> >>Then just add the workaround to the init routine.
> >>-Chris
> >>
> 
> The first command here means each BLT command streamer 
> begin the parse action, when the ring tail is moving ahead.

Okay, that makes more sense. :)

I added some error checking, then realised that no error checking was done
in 2.6.36 and swore.

Applied to -next and -fixes, with a tag for stable since I presume that
some of these chips were sent to vendors for validation.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre