[Intel-gfx] [PATCH] drm/i915: Unbreak interrupts on pre-gen6

[Ville Syrjälä]

On Tue, Jul 12, 2016 at 05:47:02PM +0100, Chris Wilson wrote:
> On Tue, Jul 12, 2016 at 07:24:47PM +0300, ville.syrjala at linux.intel.com wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > Prior to gen6 we didn't have per-ring IMR registers, which means that
> > since commit 61ff75ac20ff ("drm/i915: Simplify enabling
> > user-interrupts with L3-remapping") we're now masking off all interrupts
> > when init_render_ring() gets called.
> 
> That confused me, we're just writing to a non-existent register, so it
> shouldn't have any effect.

RING_IMR(RCS) == 0x20a8 == IMR

> 
> > That's rather rude. Let's limit
> > the ring IMR frobbing to machines that actually have the per-ring IMR
> > registers.
> > 
> > Cc: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> > Fixes: 61ff75ac20ff ("drm/i915: Simplify enabling user-interrupts with L3-remapping")
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Reviewd-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> Did you see anything to cause concern? I've run this patch on gen2-9, so
> I wonder what I missed and how.
> -Chris
> 
> -- 
> Chris Wilson, Intel Open Source Technology Centre

-- 
Ville Syrjälä
Intel OTC