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

[Chris Wilson]

On Tue, Jul 12, 2016 at 10:13:48PM +0300, Ville Syrjälä wrote:
> 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

Ah (I expected the global IIR et al not to be in the ring block). And
since we unmask everything, nothing is broken at first glance.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre