The setup-bus code doesn't work correctly for configurations
with more than one display adapter in the same PCI domain.
This stuff actually is a leftover of an early 2.4 PCI setup code
and apparently it stopped working after some "bridge_ctl" changes.
So the best thing we can do is just to remove it and rely on the fact
that any firmware *has* to configure VGA port forwarding for the boot
display device properly.
But then we need to ensure that the bus->bridge_ctl will always
contain valid information collected at the probe time, therefore
the following change in pci_scan_bridge() is needed.
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is a slight disagreement between setup-bus.c code and traditional
x86 PCI setup wrt which recourses are invalid vs resources that are free
for further allocations.
In particular, in the setup-bus.c, if we failed to allocate some resource,
we nullify "start" and "flags" fields, but *not* the "end" one.
But x86 pcibios_enable_resources() does the following check:
if (!r->start && r->end) {
printk(KERN_ERR "PCI: Device %s not available because of resource collisions\n", pci_name(dev));
return -EINVAL;
which means that the device owning the offending resource cannot be
enabled.
In particular, this breaks cardbus behind the normal decode p2p bridge -
the cardbus code from setup-bus.c requests rather large IO and MEM
windows, and if it fails, the socket is completely unavailable. Which
is wrong, as the yenta code is capable to allocate smaller windows.
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Add sanity check for io[port,mem]_resource in setup-bus.c. These
resources look like "free" as they have no parents, but obviously
we must not touch them.
- In i386.c:pci_allocate_bus_resources(), if a bridge resource cannot be
allocated for some reason, then clear its flags. This prevents any child
allocations in this range, so the setup-bus code will work with a clean
resource sub-tree.
- i386.c:pcibios_enable_resources() doesn't enable bridges, as it checks
only resources 0-5, which looks like a clear bug to me. I suspect it
might break hotplug as well in some cases.
From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When hot-plugging an I/O hierarchy that contains many bridges and leaf
devices, it's possible that there are not enough resources to start all the
device present. If we fail to assign a resource, clear the corresponding
value in the pci_dev structure, so other code can take corrective action.
Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Ivan Kokshaysky