/* * drivers/pci/setup-bus.c * * Extruded from code written by * Dave Rusling (david.rusling@reo.mts.dec.com) * David Mosberger (davidm@cs.arizona.edu) * David Miller (davem@redhat.com) * * Support routines for initializing a PCI subsystem. */ /* * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru> * PCI-PCI bridges cleanup, sorted resource allocation. * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru> * Converted to allocation in 3 passes, which gives * tighter packing. Prefetchable range support. */ #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/errno.h> #include <linux/ioport.h> #include <linux/cache.h> #include <linux/slab.h> #define DEBUG_CONFIG 1 #if DEBUG_CONFIG #define DBG(x...) printk(x) #else #define DBG(x...) #endif #define ROUND_UP(x, a) (((x) + (a) - 1) & ~((a) - 1)) static void pbus_assign_resources_sorted(struct pci_bus *bus) { struct pci_dev *dev; struct resource *res; struct resource_list head, *list, *tmp; int idx; head.next = NULL; list_for_each_entry(dev, &bus->devices, bus_list) { u16 class = dev->class >> 8; /* Don't touch classless devices or host bridges or ioapics. */ if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST) continue; /* Don't touch ioapic devices already enabled by firmware */ if (class == PCI_CLASS_SYSTEM_PIC) { u16 command; pci_read_config_word(dev, PCI_COMMAND, &command); if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) continue; } pdev_sort_resources(dev, &head); } for (list = head.next; list;) { res = list->res; idx = res - &list->dev->resource[0]; if (pci_assign_resource(list->dev, idx)) { res->start = 0; res->end = 0; res->flags = 0; } tmp = list; list = list->next; kfree(tmp); } } void pci_setup_cardbus(struct pci_bus *bus) { struct pci_dev *bridge = bus->self; struct pci_bus_region region; printk("PCI: Bus %d, cardbus bridge: %s\n", bus->number, pci_name(bridge)); pcibios_resource_to_bus(bridge, ®ion, bus->resource[0]); if (bus->resource[0]->flags & IORESOURCE_IO) { /* * The IO resource is allocated a range twice as large as it * would normally need. This allows us to set both IO regs. */ printk(" IO window: %08lx-%08lx\n", region.start, region.end); pci_write_config_dword(bridge, PCI_CB_IO_BASE_0, region.start); pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0, region.end); } pcibios_resource_to_bus(bridge, ®ion, bus->resource[1]); if (bus->resource[1]->flags & IORESOURCE_IO) { printk(" IO window: %08lx-%08lx\n", region.start, region.end); pci_write_config_dword(bridge, PCI_CB_IO_BASE_1, region.start); pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1, region.end); } pcibios_resource_to_bus(bridge, ®ion, bus->resource[2]); if (bus->resource[2]->flags & IORESOURCE_MEM) { printk(" PREFETCH window: %08lx-%08lx\n", region.start, region.end); pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0, region.start); pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0, region.end); } pcibios_resource_to_bus(bridge, ®ion, bus->resource[3]); if (bus->resource[3]->flags & IORESOURCE_MEM) { printk(" MEM window: %08lx-%08lx\n", region.start, region.end); pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1, region.start); pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1, region.end); } } EXPORT_SYMBOL(pci_setup_cardbus); /* Initialize bridges with base/limit values we have collected. PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998) requires that if there is no I/O ports or memory behind the bridge, corresponding range must be turned off by writing base value greater than limit to the bridge's base/limit registers. Note: care must be taken when updating I/O base/limit registers of bridges which support 32-bit I/O. This update requires two config space writes, so it's quite possible that an I/O window of the bridge will have some undesirable address (e.g. 0) after the first write. Ditto 64-bit prefetchable MMIO. */ static void __devinit pci_setup_bridge(struct pci_bus *bus) { struct pci_dev *bridge = bus->self; struct pci_bus_region region; u32 l, io_upper16; DBG(KERN_INFO "PCI: Bridge: %s\n", pci_name(bridge)); /* Set up the top and bottom of the PCI I/O segment for this bus. */ pcibios_resource_to_bus(bridge, ®ion, bus->resource[0]); if (bus->resource[0]->flags & IORESOURCE_IO) { pci_read_config_dword(bridge, PCI_IO_BASE, &l); l &= 0xffff0000; l |= (region.start >> 8) & 0x00f0; l |= region.end & 0xf000; /* Set up upper 16 bits of I/O base/limit. */ io_upper16 = (region.end & 0xffff0000) | (region.start >> 16); DBG(KERN_INFO " IO window: %04lx-%04lx\n", region.start, region.end); } else { /* Clear upper 16 bits of I/O base/limit. */ io_upper16 = 0; l = 0x00f0; DBG(KERN_INFO " IO window: disabled.\n"); } /* Temporarily disable the I/O range before updating PCI_IO_BASE. */ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff); /* Update lower 16 bits of I/O base/limit. */ pci_write_config_dword(bridge, PCI_IO_BASE, l); /* Update upper 16 bits of I/O base/limit. */ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16); /* Set up the top and bottom of the PCI Memory segment for this bus. */ pcibios_resource_to_bus(bridge, ®ion, bus->resource[1]); if (bus->resource[1]->flags & IORESOURCE_MEM) { l = (region.start >> 16) & 0xfff0; l |= region.end & 0xfff00000; DBG(KERN_INFO " MEM window: %08lx-%08lx\n", region.start, region.end); } else { l = 0x0000fff0; DBG(KERN_INFO " MEM window: disabled.\n"); } pci_write_config_dword(bridge, PCI_MEMORY_BASE, l); /* Clear out the upper 32 bits of PREF limit. If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily disables PREF range, which is ok. */ pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0); /* Set up PREF base/limit. */ pcibios_resource_to_bus(bridge, ®ion, bus->resource[2]); if (bus->resource[2]->flags & IORESOURCE_PREFETCH) { l = (region.start >> 16) & 0xfff0; l |= region.end & 0xfff00000; DBG(KERN_INFO " PREFETCH window: %08lx-%08lx\n", region.start, region.end); } else { l = 0x0000fff0; DBG(KERN_INFO " PREFETCH window: disabled.\n"); } pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l); /* Clear out the upper 32 bits of PREF base. */ pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, 0); pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl); } /* Check whether the bridge supports optional I/O and prefetchable memory ranges. If not, the respective base/limit registers must be read-only and read as 0. */ static void pci_bridge_check_ranges(struct pci_bus *bus) { u16 io; u32 pmem; struct pci_dev *bridge = bus->self; struct resource *b_res; b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; b_res[1].flags |= IORESOURCE_MEM; pci_read_config_word(bridge, PCI_IO_BASE, &io); if (!io) { pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0); pci_read_config_word(bridge, PCI_IO_BASE, &io); pci_write_config_word(bridge, PCI_IO_BASE, 0x0); } if (io) b_res[0].flags |= IORESOURCE_IO; /* DECchip 21050 pass 2 errata: the bridge may miss an address disconnect boundary by one PCI data phase. Workaround: do not use prefetching on this device. */ if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001) return; pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); if (!pmem) { pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0xfff0fff0); pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0); } if (pmem) b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; } /* Helper function for sizing routines: find first available bus resource of a given type. Note: we intentionally skip the bus resources which have already been assigned (that is, have non-NULL parent resource). */ static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type) { int i; struct resource *r; unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH; for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) { r = bus->resource[i]; if (r == &ioport_resource || r == &iomem_resource) continue; if (r && (r->flags & type_mask) == type && !r->parent) return r; } return NULL; } /* Sizing the IO windows of the PCI-PCI bridge is trivial, since these windows have 4K granularity and the IO ranges of non-bridge PCI devices are limited to 256 bytes. We must be careful with the ISA aliasing though. */ static void pbus_size_io(struct pci_bus *bus) { struct pci_dev *dev; struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); unsigned long size = 0, size1 = 0; if (!b_res) return; list_for_each_entry(dev, &bus->devices, bus_list) { int i; for (i = 0; i < PCI_NUM_RESOURCES; i++) { struct resource *r = &dev->resource[i]; unsigned long r_size; if (r->parent || !(r->flags & IORESOURCE_IO)) continue; r_size = r->end - r->start + 1; if (r_size < 0x400) /* Might be re-aligned for ISA */ size += r_size; else size1 += r_size; } } /* To be fixed in 2.5: we should have sort of HAVE_ISA flag in the struct pci_bus. */ #if defined(CONFIG_ISA) || defined(CONFIG_EISA) size = (size & 0xff) + ((size & ~0xffUL) << 2); #endif size = ROUND_UP(size + size1, 4096); if (!size) { b_res->flags = 0; return; } /* Alignment of the IO window is always 4K */ b_res->start = 4096; b_res->end = b_res->start + size - 1; } /* Calculate the size of the bus and minimal alignment which guarantees that all child resources fit in this size. */ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type) { struct pci_dev *dev; unsigned long min_align, align, size; unsigned long aligns[12]; /* Alignments from 1Mb to 2Gb */ int order, max_order; struct resource *b_res = find_free_bus_resource(bus, type); if (!b_res) return 0; memset(aligns, 0, sizeof(aligns)); max_order = 0; size = 0; list_for_each_entry(dev, &bus->devices, bus_list) { int i; for (i = 0; i < PCI_NUM_RESOURCES; i++) { struct resource *r = &dev->resource[i]; unsigned long r_size; if (r->parent || (r->flags & mask) != type) continue; r_size = r->end - r->start + 1; /* For bridges size != alignment */ align = (i < PCI_BRIDGE_RESOURCES) ? r_size : r->start; order = __ffs(align) - 20; if (order > 11) { printk(KERN_WARNING "PCI: region %s/%d " "too large: %llx-%llx\n", pci_name(dev), i, (unsigned long long)r->start, (unsigned long long)r->end); r->flags = 0; continue; } size += r_size; if (order < 0) order = 0; /* Exclude ranges with size > align from calculation of the alignment. */ if (r_size == align) aligns[order] += align; if (order > max_order) max_order = order; } } align = 0; min_align = 0; for (order = 0; order <= max_order; order++) { unsigned long align1 = 1UL << (order + 20); if (!align) min_align = align1; else if (ROUND_UP(align + min_align, min_align) < align1) min_align = align1 >> 1; align += aligns[order]; } size = ROUND_UP(size, min_align); if (!size) { b_res->flags = 0; return 1; } b_res->start = min_align; b_res->end = size + min_align - 1; return 1; } static void __devinit pci_bus_size_cardbus(struct pci_bus *bus) { struct pci_dev *bridge = bus->self; struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; u16 ctrl; /* * Reserve some resources for CardBus. We reserve * a fixed amount of bus space for CardBus bridges. */ b_res[0].start = pci_cardbus_io_size; b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1; b_res[0].flags |= IORESOURCE_IO; b_res[1].start = pci_cardbus_io_size; b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1; b_res[1].flags |= IORESOURCE_IO; /* * Check whether prefetchable memory is supported * by this bridge. */ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) { ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0; pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl); pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); } /* * If we have prefetchable memory support, allocate * two regions. Otherwise, allocate one region of * twice the size. */ if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) { b_res[2].start = pci_cardbus_mem_size; b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1; b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; b_res[3].start = pci_cardbus_mem_size; b_res[3].end = b_res[3].start + pci_cardbus_mem_size - 1; b_res[3].flags |= IORESOURCE_MEM; } else { b_res[3].start = pci_cardbus_mem_size * 2; b_res[3].end = b_res[3].start + pci_cardbus_mem_size * 2 - 1; b_res[3].flags |= IORESOURCE_MEM; } } void pci_bus_size_bridges(struct pci_bus *bus) { struct pci_dev *dev; unsigned long mask, prefmask; list_for_each_entry(dev, &bus->devices, bus_list) { struct pci_bus *b = dev->subordinate; if (!b) continue; switch (dev->class >> 8) { case PCI_CLASS_BRIDGE_CARDBUS: pci_bus_size_cardbus(b); break; case PCI_CLASS_BRIDGE_PCI: default: pci_bus_size_bridges(b); break; } } /* The root bus? */ if (!bus->self) return; switch (bus->self->class >> 8) { case PCI_CLASS_BRIDGE_CARDBUS: /* don't size cardbuses yet. */ break; case PCI_CLASS_BRIDGE_PCI: pci_bridge_check_ranges(bus); default: pbus_size_io(bus); /* If the bridge supports prefetchable range, size it separately. If it doesn't, or its prefetchable window has already been allocated by arch code, try non-prefetchable range for both types of PCI memory resources. */ mask = IORESOURCE_MEM; prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH; if (pbus_size_mem(bus, prefmask, prefmask)) mask = prefmask; /* Success, size non-prefetch only. */ pbus_size_mem(bus, mask, IORESOURCE_MEM); break; } } EXPORT_SYMBOL(pci_bus_size_bridges); void pci_bus_assign_resources(struct pci_bus *bus) { struct pci_bus *b; struct pci_dev *dev; pbus_assign_resources_sorted(bus); list_for_each_entry(dev, &bus->devices, bus_list) { b = dev->subordinate; if (!b) continue; pci_bus_assign_resources(b); switch (dev->class >> 8) { case PCI_CLASS_BRIDGE_PCI: pci_setup_bridge(b); break; case PCI_CLASS_BRIDGE_CARDBUS: pci_setup_cardbus(b); break; default: printk(KERN_INFO "PCI: not setting up bridge %s " "for bus %d\n", pci_name(dev), b->number); break; } } } EXPORT_SYMBOL(pci_bus_assign_resources); void __init pci_assign_unassigned_resources(void) { struct pci_bus *bus; /* Depth first, calculate sizes and alignments of all subordinate buses. */ list_for_each_entry(bus, &pci_root_buses, node) { pci_bus_size_bridges(bus); } /* Depth last, allocate resources and update the hardware. */ list_for_each_entry(bus, &pci_root_buses, node) { pci_bus_assign_resources(bus); pci_enable_bridges(bus); } }