diff options
Diffstat (limited to 'arch/powerpc/kernel/pci-common.c')
| -rw-r--r-- | arch/powerpc/kernel/pci-common.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index bea11df0a79b..9979c43cc8c7 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -462,3 +462,180 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar, *start = rsrc->start - offset; *end = rsrc->end - offset; } + +/** + * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree + * @hose: newly allocated pci_controller to be setup + * @dev: device node of the host bridge + * @primary: set if primary bus (32 bits only, soon to be deprecated) + * + * This function will parse the "ranges" property of a PCI host bridge device + * node and setup the resource mapping of a pci controller based on its + * content. + * + * Life would be boring if it wasn't for a few issues that we have to deal + * with here: + * + * - We can only cope with one IO space range and up to 3 Memory space + * ranges. However, some machines (thanks Apple !) tend to split their + * space into lots of small contiguous ranges. So we have to coalesce. + * + * - We can only cope with all memory ranges having the same offset + * between CPU addresses and PCI addresses. Unfortunately, some bridges + * are setup for a large 1:1 mapping along with a small "window" which + * maps PCI address 0 to some arbitrary high address of the CPU space in + * order to give access to the ISA memory hole. + * The way out of here that I've chosen for now is to always set the + * offset based on the first resource found, then override it if we + * have a different offset and the previous was set by an ISA hole. + * + * - Some busses have IO space not starting at 0, which causes trouble with + * the way we do our IO resource renumbering. The code somewhat deals with + * it for 64 bits but I would expect problems on 32 bits. + * + * - Some 32 bits platforms such as 4xx can have physical space larger than + * 32 bits so we need to use 64 bits values for the parsing + */ +void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose, + struct device_node *dev, + int primary) +{ + const u32 *ranges; + int rlen; + int pna = of_n_addr_cells(dev); + int np = pna + 5; + int memno = 0, isa_hole = -1; + u32 pci_space; + unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size; + unsigned long long isa_mb = 0; + struct resource *res; + + printk(KERN_INFO "PCI host bridge %s %s ranges:\n", + dev->full_name, primary ? "(primary)" : ""); + + /* Get ranges property */ + ranges = of_get_property(dev, "ranges", &rlen); + if (ranges == NULL) + return; + + /* Parse it */ + while ((rlen -= np * 4) >= 0) { + /* Read next ranges element */ + pci_space = ranges[0]; + pci_addr = of_read_number(ranges + 1, 2); + cpu_addr = of_translate_address(dev, ranges + 3); + size = of_read_number(ranges + pna + 3, 2); + ranges += np; + if (cpu_addr == OF_BAD_ADDR || size == 0) + continue; + + /* Now consume following elements while they are contiguous */ + for (; rlen >= np * sizeof(u32); + ranges += np, rlen -= np * 4) { + if (ranges[0] != pci_space) + break; + pci_next = of_read_number(ranges + 1, 2); + cpu_next = of_translate_address(dev, ranges + 3); + if (pci_next != pci_addr + size || + cpu_next != cpu_addr + size) + break; + size += of_read_number(ranges + pna + 3, 2); + } + + /* Act based on address space type */ + res = NULL; + switch ((pci_space >> 24) & 0x3) { + case 1: /* PCI IO space */ + printk(KERN_INFO + " IO 0x%016llx..0x%016llx -> 0x%016llx\n", + cpu_addr, cpu_addr + size - 1, pci_addr); + + /* We support only one IO range */ + if (hose->pci_io_size) { + printk(KERN_INFO + " \\--> Skipped (too many) !\n"); + continue; + } +#ifdef CONFIG_PPC32 + /* On 32 bits, limit I/O space to 16MB */ + if (size > 0x01000000) + size = 0x01000000; + + /* 32 bits needs to map IOs here */ + hose->io_base_virt = ioremap(cpu_addr, size); + + /* Expect trouble if pci_addr is not 0 */ + if (primary) + isa_io_base = + (unsigned long)hose->io_base_virt; +#endif /* CONFIG_PPC32 */ + /* pci_io_size and io_base_phys always represent IO + * space starting at 0 so we factor in pci_addr + */ + hose->pci_io_size = pci_addr + size; + hose->io_base_phys = cpu_addr - pci_addr; + + /* Build resource */ + res = &hose->io_resource; + res->flags = IORESOURCE_IO; + res->start = pci_addr; + break; + case 2: /* PCI Memory space */ + printk(KERN_INFO + " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n", + cpu_addr, cpu_addr + size - 1, pci_addr, + (pci_space & 0x40000000) ? "Prefetch" : ""); + + /* We support only 3 memory ranges */ + if (memno >= 3) { + printk(KERN_INFO + " \\--> Skipped (too many) !\n"); + continue; + } + /* Handles ISA memory hole space here */ + if (pci_addr == 0) { + isa_mb = cpu_addr; + isa_hole = memno; + if (primary || isa_mem_base == 0) + isa_mem_base = cpu_addr; + } + + /* We get the PCI/Mem offset from the first range or + * the, current one if the offset came from an ISA + * hole. If they don't match, bugger. + */ + if (memno == 0 || + (isa_hole >= 0 && pci_addr != 0 && + hose->pci_mem_offset == isa_mb)) + hose->pci_mem_offset = cpu_addr - pci_addr; + else if (pci_addr != 0 && + hose->pci_mem_offset != cpu_addr - pci_addr) { + printk(KERN_INFO + " \\--> Skipped (offset mismatch) !\n"); + continue; + } + + /* Build resource */ + res = &hose->mem_resources[memno++]; + res->flags = IORESOURCE_MEM; + if (pci_space & 0x40000000) + res->flags |= IORESOURCE_PREFETCH; + res->start = cpu_addr; + break; + } + if (res != NULL) { + res->name = dev->full_name; + res->end = res->start + size - 1; + res->parent = NULL; + res->sibling = NULL; + res->child = NULL; + } + } + + /* Out of paranoia, let's put the ISA hole last if any */ + if (isa_hole >= 0 && memno > 0 && isa_hole != (memno-1)) { + struct resource tmp = hose->mem_resources[isa_hole]; + hose->mem_resources[isa_hole] = hose->mem_resources[memno-1]; + hose->mem_resources[memno-1] = tmp; + } +} |
