has the i915 "black screen" boot issue returned? [BISECTED]

[Rafael J. Wysocki]

On Friday, January 28, 2011, Robert P. J. Day wrote:
> On Fri, 28 Jan 2011, Chris Wilson wrote:
> 
> > On Fri, 28 Jan 2011 09:51:01 -0500 (EST), "Robert P. J. Day" <rpjday at crashcourse.ca> wrote:
> > >   sadly, no change -- still black screen.  again, rebooted
> > > successfully under commit 8a327f23.  just to be clear, here's "git
> > > diff":
> > >
> > > $ git diff
> > > diff --git a/include/linux/acpi_io.h b/include/linux/acpi_io.h
> > > index 7180013..e035f3c 100644
> > > --- a/include/linux/acpi_io.h
> > > +++ b/include/linux/acpi_io.h
> > > @@ -7,7 +7,7 @@
> > >  static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
> > >                                             acpi_size size)
> > >  {
> > > -       return ioremap_cache(phys, size);
> > > +       return ioremap(phys, size);
> > >  }
> >
> > Ok, that implies the new mapping is fine and not the cause of the issue.
> >
> > Instead you have some OpRegion related regression hidden until till now
> > because the conflicting mapping disabled it for i915.
> >
> > That would be easy to test by returning early in intel_opregion_setup():
> >
> > diff --git a/drivers/gpu/drm/i915/intel_opregion.c
> > b/drivers/gpu/drm/i915/intel_
> > index 9efccb9..8c93201 100644
> > --- a/drivers/gpu/drm/i915/intel_opregion.c
> > +++ b/drivers/gpu/drm/i915/intel_opregion.c
> > @@ -470,6 +470,8 @@ int intel_opregion_setup(struct drm_device *dev)
> >         u32 asls, mboxes;
> >         int err = 0;
> >
> > +       return -ENOTSUPP;
> > +
> >
> >         pci_read_config_dword(dev->pdev, PCI_ASLS, &asls);
> >         DRM_DEBUG_DRIVER("graphic opregion physical addr: 0x%x\n", asls);
> >         if (asls == 0) {
> >
> 
> so you want me to revert to a stock b705120e before doing the above?

Alternatively, you could take the vanilla Linus' tree and replace
ioremap_cache() with ioremap() in include/linux/acpi_io.h .  Please try that
and see if it makes a difference.

Thanks,
Rafael