[Intel-gfx] [PATCH] DRI2: Don't swap pipes under DRI2

[Jesse Barnes]

On Tuesday, January 13, 2009 1:19 am Li Peng wrote:
> On Tue, 2009-01-13 at 15:27 +0800, Zhenyu Wang wrote:
> > On 2009.01.07 18:38:19 -0800, Jesse Barnes wrote:
> > > On Wednesday, January 7, 2009 6:25 pm Li Peng wrote:
> > > > Resend to fix patch format
> > > >
> > > > >From ea9fc2a5c4737d26464bb4533ff0c8af739f42f4 Mon Sep 17 00:00:00
> > > > > 2001
> > > >
> > > > From: Li Peng <peng.li at intel.com>
> > > > Date: Thu, 8 Jan 2009 10:13:05 +0800
> > > > Subject: Don't swap pipes under DRI2, it fixes VT switch failure on
> > > > 945GM
> > > >
> > > > Signed-off-by: Li Peng <peng.li at intel.com>
> > > > ---
> > > >  src/i830_driver.c |    1 +
> > > >  1 files changed, 1 insertions(+), 0 deletions(-)
> > > >
> > > > diff --git a/src/i830_driver.c b/src/i830_driver.c
> > > > index beb134d..5489890 100644
> > > > --- a/src/i830_driver.c
> > > > +++ b/src/i830_driver.c
> > > > @@ -2960,6 +2960,7 @@ I830SwapPipes(ScrnInfoPtr pScrn)
> > > >      * Also make sure the DRM can handle the swap.
> > > >      */
> > > >     if (I830LVDSPresent(pScrn) && !IS_I965GM(pI830) &&
> > > > !IS_GM45(pI830) && +       (pI830->directRenderingType != DRI_DRI2)
> > > > &&
> > > >         (pI830->directRenderingType != DRI_XF86DRI ||
> > > >  	(pI830->directRenderingType == DRI_XF86DRI && pI830->drmMinor >=
> > > > 10))) { xf86DrvMsg(pScrn->scrnIndex, X_INFO, "adjusting plane->pipe
> > > > mappings "
> > >
> > > It would be nice if we could allow the pipe/plane swap and make DRI2
> > > work correctly in that case.  But I just ran into this today too, so it
> > > would be nice to have fixed or at least worked around for now (i.e.
> > > this should go into the 2.6 release).
> >
> > drmMinor is still 6 in kernel now, so this swapping never happen now,
> > which means fbc on pre-965 mobile has already been broken.
> >
> > So many difference between recent drm i915 vs. code in origin drm git,
> > that I don't know what should be the right fix. We may disable fbc now
> > for 2.6.0, and fix it later. Idea?
>
> Disable fbc doesn't fix this problem in my test on 945GM.

An alternate fix for this is to prevent waiting on disabled pipes and to 
timeout properly in libdrm's vblank wait function.  Both of those patches are 
upstream now so this one shouldn't be required.

-- 
Jesse Barnes, Intel Open Source Technology Center