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[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>
This commit is contained in:
Benjamin Herrenschmidt 2007-12-20 14:55:04 +11:00 committed by Paul Mackerras
parent d0264ce796
commit be8cbcd889
1 changed files with 22 additions and 0 deletions
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22
arch/powerpc/kernel/pci-common.c
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@ -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,\