Xorg/ATI failure with Linux 2.6.22 (sparc64)

[ludo@chbouib.org (Ludovic Courtès)]

Hi,

After upgrading my Ultra 5 to `linux-image-2.6.22-1-sparc64', I noticed
that Xorg (ATI driver) would fail to run:

  X Window System Version 1.3.0
  Release Date: 19 April 2007
  X Protocol Version 11, Revision 0, Release 1.3
  Build Operating System: Linux Debian
  Current Operating System: Linux sabre 2.6.22-1-sparc64 #1 Tue Jul 24 06:42:28 UTC 2007 sparc64
  Build Date: 14 July 2007
          Before reporting problems, check http://wiki.x.org
          to make sure that you have the latest version.

  [...]

  (II) Module atimisc: vendor="X.Org Foundation"
          compiled for 7.1.1, module version = 6.6.3
          Module class: X.Org Video Driver
          ABI class: X.Org Video Driver, version 1.0
  (WW) ****INVALID MEM ALLOCATION**** b: 0xe1000000 e: 0xe1ffffff correcting^G

  [...]

  (==) ATI(0): Chipset:  "ati".
  (**) ATI(0): Depth 24, (--) framebuffer bpp 32
  (==) ATI(0): Using XAA acceleration architecture

  Fatal server error:
  xf86MapPciMem: Could not mmap PCI memory [base=0x100000,hostbase=0x100000,size=2000] (Invalid argument)

>From `strace', the failure looks like this:

  open("/proc/bus/pci/0000:01/02.0", O_RDWR) = 7
  ioctl(7, IIOCNETDIF, 0)                 = 0
  ioctl(7, IIOCNETSCF, 0)                 = 0
  mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_SHARED, 7, 0x100000) = -1 EINVAL (Invalid argument)
  write(2, "\nFatal server error:\n", 21) = 21

The same server works fine with `linux-image-2.6.18-1-sparc64'.

The exact version of the Xorg packages are:

  xserver-xorg                     7.2-5
  xserver-xorg-core                1.3.0.0.dfsg-11
  xserver-xorg-video-ati           6.6.3-2
  
Any hints?

Thanks,
Ludovic.