linux-3.3-rc2 and radeon kms failure on ppc32 with Radeon X1650PRO pcie

[Michel Dänzer]

On Don, 2012-02-16 at 01:05 +0000, acrux wrote: 
> On Thu, 16 Feb 2012 07:28:10 +1100
> Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:
> 
> > On Wed, 2012-02-15 at 08:39 +0100, Michel Dänzer wrote:
> > 
> > > > > Btw, to sum up the list of Power Architecture machines with
> > > > > PCIE  that aim to be a desktop/workstation: Apple iMac G5
> > > > > (iSight), Apple PowerMac Quad G5, YDL Powerstation 2x970MP and
> > > > > Acube Sam460ex . And the last two, on present evidence (my
> > > > > attempts), aren't able to boot up if bootkernel has kms enabled.
> > > > 
> > > > Which radeon card, kernel log please ?
> > > 
> > > See
> > > http://lists.freedesktop.org/archives/dri-devel/2012-February/018792.html
> > > (start of this thread) and
> > > http://lists.freedesktop.org/archives/dri-devel/2012-February/018791.html .
> > 
> > Ok, so for the 460EX, I am not surprised things aren't working with
> > KMS & DRI2... the 460 is not cache coherent, and this is not handled
> > by TTM as far as I can tell.
> > 
> > The second case with no firmware is a bit more surprising, looks like
> > something bad happened on the PCI express bus or the kernel tried to
> > access something that the card rejected (target abort or PCIe
> > equivalent most likely), thus triggering a PLB error . That could be
> > investigated a bit more.

AFAICT in both cases the immediate problem is the PLB error on first
access to VRAM, indicating some kind of problem with ioremap_wc() or
generally PCIe device memory access.


> Anyway after nearly ten years, due a lack in resources, i'm sadly going
> to suspend the CRUX PPC project and my activism pro free
> software thus i'm unable to follow these debug. I'll hold on to me
> the only YDL Powerstation then from the next weeks i'll can only follow
> trying to help in debug [1] on this specific machine.  
> 
> [1]http://lists.freedesktop.org/archives/dri-devel/2012-January/018575.html

For that one, I'd try adding some more debugging output to
radeon_get_bios() to find out which method it ends up using to retrieve
the ROM contents, and why it doesn't look like it's an ATOM BIOS.

Does the same card work in an x86 machine?


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer