Re: [PATCH] drm/i915: Flush writes to GMBUS registers

From: Chris Wilson <chris@chris-wilson.co.uk>
To: Jiri Kosina <jkosina@suse.cz>
Cc: linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org,
	Shawn Starr <shawn.starr@rogers.com>,
	Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: Re: [PATCH] drm/i915: Flush writes to GMBUS registers
Date: Mon, 18 Mar 2013 12:48:41 +0000	[thread overview]
Message-ID: <20130318124841.GA3995@cantiga.alporthouse.com> (raw)
In-Reply-To: <alpine.LNX.2.00.1303181251040.9529@pobox.suse.cz>

On Mon, Mar 18, 2013 at 12:51:45PM +0100, Jiri Kosina wrote:
> On Mon, 18 Mar 2013, Chris Wilson wrote:
> 
> > If we do not complete the writes to the GMBUS registers, they remain
> > active for an indefinite period of time afterwards, even causing
> > spurious interrupts on gm45.
> > 
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1303151424140.9529@pobox.suse.cz
> > Cc: Shawn Starr <shawn.starr@rogers.com>
> > Cc: Jiri Kosina <jkosina@suse.cz>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> Unfortunately I can't provide my Tested-by or Acked-by for this, as I am 
> still seeing the "nobody cared" for irq 16 with this patch applied.

The message reappeared on the third reboot. Perhaps an indicator that it
is a timing issue. I guess the sensible approach then is to exclude gen4
from the whitelist for gmbus irqs.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre