Re: [PATCH] drm/i915: Do hw quiescing first during unload

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Oct 18, 2013 at 11:09:15AM -0700, Ben Widawsky wrote:
> On Fri, Oct 18, 2013 at 10:36:30AM +0300, Ville Syrjälä wrote:
> > On Thu, Oct 17, 2013 at 02:04:34PM -0700, Ben Widawsky wrote:
> > > On Thu, Oct 17, 2013 at 08:37:44PM +0100, Chris Wilson wrote:
> > > > On Thu, Oct 17, 2013 at 12:07:26PM -0700, Ben Widawsky wrote:
> > > > > On Thu, Oct 17, 2013 at 01:02:53PM +0100, Chris Wilson wrote:
> > > > > > If we force the hw to idle as our first step during unload, we can abort
> > > > > > the unload upon failure. Later we can probe whether the hardware remain
> > > > > > active even after we try to shut it down.
> > > > > > 
> > > > > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > > > > 
> > > > > Isn't it pretty mean to fail to unload? Wouldn't pci_clear_master yield
> > > > > what we want?
> > > > 
> > > > It may be mean, but it seems to me to be the right thing to do if we
> > > > cannot turn off the hardware to unload the driver...
> > > > -Chris
> > > > 
> > > > -- 
> > > > Chris Wilson, Intel Open Source Technology Centre
> > > 
> > > And what about my suggestion of simply using pci_clear_master?
> > 
> > Might that hang some boxes?
> > 
> 
> Hmm, why are you thinking?

No particular reason. Just my well honed "hardware is often borked"
reflex.

-- 
Ville Syrjälä
Intel OTC