[Intel-gfx] [PATCH] [RFC] drm/i915: Unmask all render responses for SNB

[Chris Wilson]

On Fri, 23 Sep 2011 11:21:29 +0100, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On SandyBridge in order to receive an event on the RENDER ring, you
> first must unmask the corresponding bit in the DERRMR (Display Engine
> Render Response Mask Register). This register is not accessible from a
> non-secure MI_LOAD_REGISTER_IMM so resort to unmasking all events upon
> initialisation. Presumably this leads to an undesirable increase in PCI
> traffic (possibly 4 additional wakeups per vblank per active pipe).

I should mention that my docs have this as SNB only, but that seems a
little strage...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre