On Wed, Dec 14, 2011 at 03:34:38PM +0000, Chris Wilson wrote: > On Wed, 14 Dec 2011 13:57:40 +0100, Daniel Vetter <daniel.vetter at ffwll.ch> wrote: > > v2: Don't try to enable ppgtt on pre-snb. > > > > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch> > > Reviewed-by: Ben Widawsky <ben at bwidawsk.net> > > --- > > +void i915_gem_init_ppgtt(struct drm_device *dev) > > +{ > > + drm_i915_private_t *dev_priv = dev->dev_private; > > + uint32_t pd_offset; > > + struct intel_ring_buffer *ring; > > + int i; > > + > > + if (!HAS_ALIASING_PPGTT(dev)) > > + return; > I still think it is safer to use > if (dev_priv->mm.aliasing_ppgtt == NULL) > return; > here > > And pretty please can I module parameter to enable/disable ppgtt on > boot. I hope we can really avoid this. Working ppgtt is more or less required by a bunch of things, and will at least result in strange suprises with real per-process address spaces. Disabling the use of ppgtt with the current code can be easily done by resetting the NON_SECURE flag in the MI_START_BB cmd (or disabling all of it in the HAS_ALIASING_PPGTT macro). This should be good enough to hammer out any outstanding issues with this. -Daniel -- Daniel Vetter Mail: daniel at ffwll.ch Mobile: +41 (0)79 365 57 48