System76 - Intel DRM patch

Andy Whitcroft apw at canonical.com
Mon Apr 2 11:34:49 UTC 2012


On Sun, Apr 01, 2012 at 10:34:15PM -0400, Robert Hooker wrote:
> On Sun, Apr 1, 2012 at 5:55 PM, Carl Richell <carl at system76.com> wrote:
> > Hi,
> >
> > We'd like to make sure 12.04 is flawless on our next-gen laptops. A kernel
> > patch is required to fix an offset desktop bug. The patch applies cleanly on
> > the current precise kernel. Please see:
> >
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/968307
> >
> > https://bugzilla.kernel.org/show_bug.cgi?id=43012
> >
> >
> > -- Carl
> >
> > References: https://bugs.freedesktop.org/show_bug.cgi?id=47271
> > Signed-off-by: Chris Wilson<chris at chris-wilson.co.uk>
> > Cc: stable at kernel.org
> > ---
> >  drivers/gpu/drm/i915/i915_reg.h      |    1 +
> >  drivers/gpu/drm/i915/intel_display.c |    6 ++++++
> >  2 files changed, 7 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_reg.h
> > b/drivers/gpu/drm/i915/i915_reg.h
> > index 3d9ba01..218b3db9 100644
> > --- a/drivers/gpu/drm/i915/i915_reg.h
> > +++ b/drivers/gpu/drm/i915/i915_reg.h
> > @@ -2385,6 +2385,7 @@
> >  #define   PIPECONF_DISABLE     0
> >  #define   PIPECONF_DOUBLE_WIDE (1<<30)
> >  #define   I965_PIPECONF_ACTIVE (1<<30)
> > +#define   PIPECONF_FRAME_START_DELAY_MASK (3<<27)
> >  #define   PIPECONF_SINGLE_WIDE 0
> >  #define   PIPECONF_PIPE_UNLOCKED 0
> >  #define   PIPECONF_PIPE_LOCKED (1<<25)
> > diff --git a/drivers/gpu/drm/i915/intel_display.c
> > b/drivers/gpu/drm/i915/intel_display.c
> > index 6b0562b..73ea6e9 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -7695,6 +7695,12 @@ static void intel_sanitize_modesetting(struct
> > drm_device *dev,
> >        struct drm_i915_private *dev_priv = dev->dev_private;
> >        u32 reg, val;
> >
> > +       /* Clear any frame start delays used for debugging left by the BIOS
> > */
> > +       for_each_pipe(pipe) {
> > +               reg = PIPECONF(pipe);
> > +               I915_WRITE(reg, I915_READ(reg)&
> >  ~PIPECONF_FRAME_START_DELAY_MASK);
> > +       }
> > +
> >        if (HAS_PCH_SPLIT(dev))
> >                return;
> >
> >
> >
> > --
> > kernel-team mailing list
> > kernel-team at lists.ubuntu.com
> > https://lists.ubuntu.com/mailman/listinfo/kernel-team
> 
> This even hit some machines we at Canonical have in the past few days
> and I was going to propose this as well. Note: It's specific to
> machines with v2132 vbios versions, and will very likely be fixed in a
> later vbios but it's pretty safe to say this vbios may ship in some
> early panther point machines and causes screen corruption such as
> http://ubuntuone.com/69BR1liJd25E6DRNqytGJF on boot so it would be
> good to have in time to make the livecd's kernel. The original commit
> message that will go upstream is here
> http://lists.freedesktop.org/archives/intel-gfx/2012-March/015696.html
> which also had
> 
> Reported-and-tested-by: Carl Richell <carl at system76.com>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43012
> 
> added in http://lists.freedesktop.org/archives/intel-gfx/2012-March/016097.html
> 
> Acked-by: Robert Hooker <sarvatt at canonical.com>

Got a reference to where this got applied.  I find finding the current
owner of the various drm trees hard to determine, and frankly I am no
longer sure the MAINTAINERS entries are accurate since the kernel.org
issues.

-apw



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