diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2007-12-20 14:55:04 +1100 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2007-12-20 16:18:15 +1100 |
| commit | be8cbcd8896670a01ead7a29e33ffe29604ed734 (patch) | |
| tree | c4253a4191279a74d7896099dab13fb57b1a9d27 | |
| parent | d0264ce796e4e3d77fdadf72d6625f8e6c1c96bd (diff) | |
[POWERPC] Fixup skipping of PowerMac PCI<->PCI bridge "closed" resources
Apple firmware has a strange way to "close" bridge resources by setting
them to some bogus values that overlap RAM (strangely, I haven't seen it
conflicting with DMA so far...). This explicitely closes them to avoid
problems. Previously, they would be closed as a consequence of failing
to be allocated, but this makes it more explicit, and thus the log
message is more explicit too.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
| -rw-r--r-- | arch/powerpc/kernel/pci-common.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index b6d4767e4e2..1037b3a093e 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -776,6 +776,7 @@ DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources); static void __devinit __pcibios_fixup_bus(struct pci_bus *bus) { + struct pci_controller *hose = pci_bus_to_host(bus); struct pci_dev *dev = bus->self; pr_debug("PCI: Fixup bus %d (%s)\n", bus->number, dev ? pci_name(dev) : "PHB"); @@ -793,6 +794,27 @@ static void __devinit __pcibios_fixup_bus(struct pci_bus *bus) if (!res->flags || bus->self->transparent) continue; + /* On PowerMac, Apple leaves bridge windows open over + * an inaccessible region of memory space (0...fffff) + * which is somewhat bogus, but that's what they think + * means disabled... + * + * We clear those to force them to be reallocated later + * + * We detect such regions by the fact that the base is + * equal to the pci_mem_offset of the host bridge and + * their size is smaller than 1M. + */ + if (res->start == hose->pci_mem_offset && + res->end < 0x100000) { + printk(KERN_INFO + "PCI: Closing bogus Apple Firmware" + " region %d on bus 0x%02x\n", + i, bus->number); + res->flags = 0; + continue; + } + pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n", pci_name(dev), i, (unsigned long long)res->start,\ |