The special support for HP IA64 ZX1/ZX2 PCI buses is currently disabled as the
PCI bridge range detection code assumes that if non of the other well known
chipsets is found a ZX1 chipset is present and pokes around some addresses which
can bring other not detected systems to a grinding halt.
Since ZX1/ZX2 systems can only be probed thru ACPI there is no generic way to
probe them (unless one seriously considers to add ACPI code to X which should
live in the kernel). Instead it is necessary to probe for this chipset using an
OS dependent method. The IA64 PCI code originally from XFree86 did not support
this (unlike the AXP PCI code).
The patch that's going to be appended below adds this support (it works
similarly as the AXP code) and reenables PCI bridge support for these chipsets.
In the long run a lot of this code should disappear into the kernel. However I
assume that we will still need this code for platforms that don't have the
required kernel support.
Created attachment 730 [details] [review]
The following patch adds OS dependent PCI bridge probing for IA64 PCI systems
including a very cheesy probe for ZX1/ZX2 systems on Linux.
I'm making this a blocker of the release to bring it to the attention of the
We have the option to
1. reenable the original ZX1/ZX2 code.
2. Add this patch which will provide save ZX1/ZX2 support for Linux however
non for other OSes (unless somebody implements it)
3. Do nothing. With a single head ZX1/ZX2 systems may work even without bridge
We haven't heard back on this issue yet from HP. As discussed on the release
wranglers call today, if we get an answer before the deadline (today 6pm EDT)
that we should definitely include the patch, we can still do so. Otherwise, it
will need to be discussed and fixed after the current release.
Moving to release notes bug 999 as noted on the release wranglers call, which
will allow this issue to be documented and then later moved to block the next
release after X11R6.8.
I've got confirmation from HP that this works on the systrems they have tested.
Therefore I will commit it now.