diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 8c0270929cc0..01ce8c38bae6 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -780,11 +780,6 @@ static void __devinit fixup_resource(struct resource *res, struct pci_dev *dev) res->start = (res->start + offset) & mask; res->end = (res->end + offset) & mask; - - pr_debug("PCI:%s %016llx-%016llx\n", - pci_name(dev), - (unsigned long long)res->start, - (unsigned long long)res->end); } @@ -830,6 +825,11 @@ static void __devinit pcibios_fixup_resources(struct pci_dev *dev) (unsigned int)res->flags); fixup_resource(res, dev); + + pr_debug("PCI:%s %016llx-%016llx\n", + pci_name(dev), + (unsigned long long)res->start, + (unsigned long long)res->end); } /* Call machine specific resource fixup */ @@ -838,58 +838,127 @@ static void __devinit pcibios_fixup_resources(struct pci_dev *dev) } DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources); -static void __devinit __pcibios_fixup_bus(struct pci_bus *bus) +/* This function tries to figure out if a bridge resource has been initialized + * by the firmware or not. It doesn't have to be absolutely bullet proof, but + * things go more smoothly when it gets it right. It should covers cases such + * as Apple "closed" bridge resources and bare-metal pSeries unassigned bridges + */ +static int __devinit pcibios_uninitialized_bridge_resource(struct pci_bus *bus, + struct resource *res) { struct pci_controller *hose = pci_bus_to_host(bus); struct pci_dev *dev = bus->self; + resource_size_t offset; + u16 command; + int i; + + /* We don't do anything if PCI_PROBE_ONLY is set */ + if (ppc_pci_flags & PPC_PCI_PROBE_ONLY) + return 0; + + /* Job is a bit different between memory and IO */ + if (res->flags & IORESOURCE_MEM) { + /* If the BAR is non-0 (res != pci_mem_offset) then it's probably been + * initialized by somebody + */ + if (res->start != hose->pci_mem_offset) + return 0; + + /* The BAR is 0, let's check if memory decoding is enabled on + * the bridge. If not, we consider it unassigned + */ + pci_read_config_word(dev, PCI_COMMAND, &command); + if ((command & PCI_COMMAND_MEMORY) == 0) + return 1; + + /* Memory decoding is enabled and the BAR is 0. If any of the bridge + * resources covers that starting address (0 then it's good enough for + * us for memory + */ + for (i = 0; i < 3; i++) { + if ((hose->mem_resources[i].flags & IORESOURCE_MEM) && + hose->mem_resources[i].start == hose->pci_mem_offset) + return 0; + } + + /* Well, it starts at 0 and we know it will collide so we may as + * well consider it as unassigned. That covers the Apple case. + */ + return 1; + } else { + /* If the BAR is non-0, then we consider it assigned */ + offset = (unsigned long)hose->io_base_virt - _IO_BASE; + if (((res->start - offset) & 0xfffffffful) != 0) + return 0; + + /* Here, we are a bit different than memory as typically IO space + * starting at low addresses -is- valid. What we do instead if that + * we consider as unassigned anything that doesn't have IO enabled + * in the PCI command register, and that's it. + */ + pci_read_config_word(dev, PCI_COMMAND, &command); + if (command & PCI_COMMAND_IO) + return 0; + + /* It's starting at 0 and IO is disabled in the bridge, consider + * it unassigned + */ + return 1; + } +} + +/* Fixup resources of a PCI<->PCI bridge */ +static void __devinit pcibios_fixup_bridge(struct pci_bus *bus) +{ + struct resource *res; + int i; + + struct pci_dev *dev = bus->self; + + for (i = 0; i < PCI_BUS_NUM_RESOURCES; ++i) { + if ((res = bus->resource[i]) == NULL) + continue; + if (!res->flags) + continue; + if (i >= 3 && bus->self->transparent) + continue; + + pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n", + pci_name(dev), i, + (unsigned long long)res->start,\ + (unsigned long long)res->end, + (unsigned int)res->flags); + + /* Perform fixup */ + fixup_resource(res, dev); + + /* Try to detect uninitialized P2P bridge resources, + * and clear them out so they get re-assigned later + */ + if (pcibios_uninitialized_bridge_resource(bus, res)) { + res->flags = 0; + pr_debug("PCI:%s (unassigned)\n", pci_name(dev)); + } else { + + pr_debug("PCI:%s %016llx-%016llx\n", + pci_name(dev), + (unsigned long long)res->start, + (unsigned long long)res->end); + } + } +} + +static void __devinit __pcibios_fixup_bus(struct pci_bus *bus) +{ + struct pci_dev *dev = bus->self; pr_debug("PCI: Fixup bus %d (%s)\n", bus->number, dev ? pci_name(dev) : "PHB"); /* Fixup PCI<->PCI bridges. Host bridges are handled separately, for * now differently between 32 and 64 bits. */ - if (dev != NULL) { - struct resource *res; - int i; - - for (i = 0; i < PCI_BUS_NUM_RESOURCES; ++i) { - if ((res = bus->resource[i]) == NULL) - continue; - if (!res->flags) - continue; - if (i >= 3 && 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->flags & IORESOURCE_MEM && - 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,\ - (unsigned long long)res->end, - (unsigned int)res->flags); - - fixup_resource(res, dev); - } - } + if (dev != NULL) + pcibios_fixup_bridge(bus); /* Additional setup that is different between 32 and 64 bits for now */ pcibios_do_bus_setup(bus);