Re: Radeon DRM dom0 issues

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Jan 20, 2014 at 03:15:24PM -0500, Michael D Labriola wrote:
> Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> wrote on 01/20/2014 
> 10:38:27 AM:
> 
> > From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> > To: Michael D Labriola <mlabriol@gdeb.com>, 
> > Cc: Konrad Rzeszutek Wilk <konrad@darnok.org>, 
> > michael.d.labriola@gmail.com, xen-devel@lists.xen.org
> > Date: 01/20/2014 10:38 AM
> > Subject: Re: [Xen-devel] Radeon DRM dom0 issues
> > 
> > On Mon, Jan 20, 2014 at 10:26:22AM -0500, Michael D Labriola wrote:
> > > Konrad Rzeszutek Wilk <konrad@darnok.org> wrote on 01/20/2014 10:14:36 
> AM:
> > > 
> > > > From: Konrad Rzeszutek Wilk <konrad@darnok.org>
> > > > To: Michael D Labriola <mlabriol@gdeb.com>, 
> > > > Cc: xen-devel@lists.xen.org, michael.d.labriola@gmail.com
> > > > Date: 01/20/2014 10:14 AM
> > > > Subject: Re: [Xen-devel] Radeon DRM dom0 issues
> > > > 
> > > > On Mon, Jan 20, 2014 at 09:58:32AM -0500, Michael D Labriola wrote:
> > > > > Anyone here running a dom0 w/ Radeon DRM?  I'm having consistent 
> > > crashes 
> > > > > with multiple older R600 series (HD 6470 and HD 6570) and unusably 
> 
> > > slow 
> > > > > graphics with a newer HD7000 (can see each line refresh 
> indiviually on 
> > > 
> > > > > radeonfb tty).  All 3 systems seem to work fine bare metal.
> > > > 
> > > > I hadn't been using DRM, just Xserver. Is that what you mean?
> > > 
> > > The R600 problems happen when in X, using OpenGL, on my dom0.  The 
> > > RadeonSI sluggishness is when using the KMS framebuffer device for a 
> plain 
> > > text console login.
> > 
> > So sluggish is probably due to the PAT not being enabled. This patch
> > should be applied:
> > 
> > lkml.org/lkml/2011/11/8/406
> > 
> > (or http://marc.info/?l=linux-kernel&m=132888833209874&w=2)
> > 
> > and these two reverted:
> > 
> >  "xen/pat: Disable PAT support for now."
> >  "xen/pat: Disable PAT using pat_enabled value."
> > 
> > Which is to say do:
> > 
> > git revert c79c49826270b8b0061b2fca840fc3f013c8a78a
> > git revert 8eaffa67b43e99ae581622c5133e20b0f48bcef1
> 
> Thanks!  I cherry-picked that patch out of your testing tree, reverted 
> those 2 commits, recompiled and installed.  Definitely fixed the HD 7000 
> sluggishness and appears to have fixed the R600 crashes (although it's 
> only been running a few hours).
> 
> How come that patch didn't get into mainline?  It looks pretty innocuous 
> to me...

<Sigh> the x86 maintainers wanted a different route. And I hadn't had
the chance nor time to implement it.


> 
> ---
> Michael D Labriola
> Electric Boat
> mlabriol@gdeb.com
> 401-848-8871 (desk)
> 401-848-8513 (lab)
> 401-316-9844 (cell)
> 
> 
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