// SPDX-License-Identifier: GPL-2.0 /* * Support routines for initializing a PCI subsystem * * Extruded from code written by * Dave Rusling (david.rusling@reo.mts.dec.com) * David Mosberger (davidm@cs.arizona.edu) * David Miller (davem@redhat.com) * * Nov 2000, Ivan Kokshaysky * PCI-PCI bridges cleanup, sorted resource allocation. * Feb 2002, Ivan Kokshaysky * Converted to allocation in 3 passes, which gives * tighter packing. Prefetchable range support. */ #include #include #include #include #include #include #include #include #include #include "pci.h" unsigned int pci_flags; struct pci_dev_resource { struct list_head list; struct resource *res; struct pci_dev *dev; resource_size_t start; resource_size_t end; resource_size_t add_size; resource_size_t min_align; unsigned long flags; }; static void free_list(struct list_head *head) { struct pci_dev_resource *dev_res, *tmp; list_for_each_entry_safe(dev_res, tmp, head, list) { list_del(&dev_res->list); kfree(dev_res); } } /** * add_to_list() - Add a new resource tracker to the list * @head: Head of the list * @dev: Device to which the resource belongs * @res: Resource to be tracked * @add_size: Additional size to be optionally added to the resource */ static int add_to_list(struct list_head *head, struct pci_dev *dev, struct resource *res, resource_size_t add_size, resource_size_t min_align) { struct pci_dev_resource *tmp; tmp = kzalloc(sizeof(*tmp), GFP_KERNEL); if (!tmp) return -ENOMEM; tmp->res = res; tmp->dev = dev; tmp->start = res->start; tmp->end = res->end; tmp->flags = res->flags; tmp->add_size = add_size; tmp->min_align = min_align; list_add(&tmp->list, head); return 0; } static void remove_from_list(struct list_head *head, struct resource *res) { struct pci_dev_resource *dev_res, *tmp; list_for_each_entry_safe(dev_res, tmp, head, list) { if (dev_res->res == res) { list_del(&dev_res->list); kfree(dev_res); break; } } } static struct pci_dev_resource *res_to_dev_res(struct list_head *head, struct resource *res) { struct pci_dev_resource *dev_res; list_for_each_entry(dev_res, head, list) { if (dev_res->res == res) return dev_res; } return NULL; } static resource_size_t get_res_add_size(struct list_head *head, struct resource *res) { struct pci_dev_resource *dev_res; dev_res = res_to_dev_res(head, res); return dev_res ? dev_res->add_size : 0; } static resource_size_t get_res_add_align(struct list_head *head, struct resource *res) { struct pci_dev_resource *dev_res; dev_res = res_to_dev_res(head, res); return dev_res ? dev_res->min_align : 0; } /* Sort resources by alignment */ static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head) { int i; for (i = 0; i < PCI_NUM_RESOURCES; i++) { struct resource *r; struct pci_dev_resource *dev_res, *tmp; resource_size_t r_align; struct list_head *n; r = &dev->resource[i]; if (r->flags & IORESOURCE_PCI_FIXED) continue; if (!(r->flags) || r->parent) continue; r_align = pci_resource_alignment(dev, r); if (!r_align) { pci_warn(dev, "BAR %d: %pR has bogus alignment\n", i, r); continue; } tmp = kzalloc(sizeof(*tmp), GFP_KERNEL); if (!tmp) panic("pdev_sort_resources(): kmalloc() failed!\n"); tmp->res = r; tmp->dev = dev; /* Fallback is smallest one or list is empty */ n = head; list_for_each_entry(dev_res, head, list) { resource_size_t align; align = pci_resource_alignment(dev_res->dev, dev_res->res); if (r_align > align) { n = &dev_res->list; break; } } /* Insert it just before n */ list_add_tail(&tmp->list, n); } } static void __dev_sort_resources(struct pci_dev *dev, struct list_head *head) { 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) return; /* 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)) return; } pdev_sort_resources(dev, head); } static inline void reset_resource(struct resource *res) { res->start = 0; res->end = 0; res->flags = 0; } /** * reassign_resources_sorted() - Satisfy any additional resource requests * * @realloc_head: Head of the list tracking requests requiring * additional resources * @head: Head of the list tracking requests with allocated * resources * * Walk through each element of the realloc_head and try to procure additional * resources for the element, provided the element is in the head list. */ static void reassign_resources_sorted(struct list_head *realloc_head, struct list_head *head) { struct resource *res; struct pci_dev_resource *add_res, *tmp; struct pci_dev_resource *dev_res; resource_size_t add_size, align; int idx; list_for_each_entry_safe(add_res, tmp, realloc_head, list) { bool found_match = false; res = add_res->res; /* Skip resource that has been reset */ if (!res->flags) goto out; /* Skip this resource if not found in head list */ list_for_each_entry(dev_res, head, list) { if (dev_res->res == res) { found_match = true; break; } } if (!found_match) /* Just skip */ continue; idx = res - &add_res->dev->resource[0]; add_size = add_res->add_size; align = add_res->min_align; if (!resource_size(res)) { res->start = align; res->end = res->start + add_size - 1; if (pci_assign_resource(add_res->dev, idx)) reset_resource(res); } else { res->flags |= add_res->flags & (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN); if (pci_reassign_resource(add_res->dev, idx, add_size, align)) pci_info(add_res->dev, "failed to add %llx res[%d]=%pR\n", (unsigned long long) add_size, idx, res); } out: list_del(&add_res->list); kfree(add_res); } } /** * assign_requested_resources_sorted() - Satisfy resource requests * * @head: Head of the list tracking requests for resources * @fail_head: Head of the list tracking requests that could not be * allocated * * Satisfy resource requests of each element in the list. Add requests that * could not be satisfied to the failed_list. */ static void assign_requested_resources_sorted(struct list_head *head, struct list_head *fail_head) { struct resource *res; struct pci_dev_resource *dev_res; int idx; list_for_each_entry(dev_res, head, list) { res = dev_res->res; idx = res - &dev_res->dev->resource[0]; if (resource_size(res) && pci_assign_resource(dev_res->dev, idx)) { if (fail_head) { /* * If the failed resource is a ROM BAR and * it will be enabled later, don't add it * to the list. */ if (!((idx == PCI_ROM_RESOURCE) && (!(res->flags & IORESOURCE_ROM_ENABLE)))) add_to_list(fail_head, dev_res->dev, res, 0 /* don't care */, 0 /* don't care */); } reset_resource(res); } } } static unsigned long pci_fail_res_type_mask(struct list_head *fail_head) { struct pci_dev_resource *fail_res; unsigned long mask = 0; /* Check failed type */ list_for_each_entry(fail_res, fail_head, list) mask |= fail_res->flags; /* * One pref failed resource will set IORESOURCE_MEM, as we can * allocate pref in non-pref range. Will release all assigned * non-pref sibling resources according to that bit. */ return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH); } static bool pci_need_to_release(unsigned long mask, struct resource *res) { if (res->flags & IORESOURCE_IO) return !!(mask & IORESOURCE_IO); /* Check pref at first */ if (res->flags & IORESOURCE_PREFETCH) { if (mask & IORESOURCE_PREFETCH) return true; /* Count pref if its parent is non-pref */ else if ((mask & IORESOURCE_MEM) && !(res->parent->flags & IORESOURCE_PREFETCH)) return true; else return false; } if (res->flags & IORESOURCE_MEM) return !!(mask & IORESOURCE_MEM); return false; /* Should not get here */ } static void __assign_resources_sorted(struct list_head *head, struct list_head *realloc_head, struct list_head *fail_head) { /* * Should not assign requested resources at first. They could be * adjacent, so later reassign can not reallocate them one by one in * parent resource window. * * Try to assign requested + add_size at beginning. If could do that, * could get out early. If could not do that, we still try to assign * requested at first, then try to reassign add_size for some resources. * * Separate three resource type checking if we need to release * assigned resource after requested + add_size try. * * 1. If IO port assignment fails, will release assigned IO * port. * 2. If pref MMIO assignment fails, release assigned pref * MMIO. If assigned pref MMIO's parent is non-pref MMIO * and non-pref MMIO assignment fails, will release that * assigned pref MMIO. * 3. If non-pref MMIO assignment fails or pref MMIO * assignment fails, will release assigned non-pref MMIO. */ LIST_HEAD(save_head); LIST_HEAD(local_fail_head); struct pci_dev_resource *save_res; struct pci_dev_resource *dev_res, *tmp_res, *dev_res2; unsigned long fail_type; resource_size_t add_align, align; /* Check if optional add_size is there */ if (!realloc_head || list_empty(realloc_head)) goto requested_and_reassign; /* Save original start, end, flags etc at first */ list_for_each_entry(dev_res, head, list) { if (add_to_list(&save_head, dev_res->dev, dev_res->res, 0, 0)) { free_list(&save_head); goto requested_and_reassign; } } /* Update res in head list with add_size in realloc_head list */ list_for_each_entry_safe(dev_res, tmp_res, head, list) { dev_res->res->end += get_res_add_size(realloc_head, dev_res->res); /* * There are two kinds of additional resources in the list: * 1. bridge resource -- IORESOURCE_STARTALIGN * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN * Here just fix the additional alignment for bridge */ if (!(dev_res->res->flags & IORESOURCE_STARTALIGN)) continue; add_align = get_res_add_align(realloc_head, dev_res->res); /* * The "head" list is sorted by alignment so resources with * bigger alignment will be assigned first. After we * change the alignment of a dev_res in "head" list, we * need to reorder the list by alignment to make it * consistent. */ if (add_align > dev_res->res->start) { resource_size_t r_size = resource_size(dev_res->res); dev_res->res->start = add_align; dev_res->res->end = add_align + r_size - 1; list_for_each_entry(dev_res2, head, list) { align = pci_resource_alignment(dev_res2->dev, dev_res2->res); if (add_align > align) { list_move_tail(&dev_res->list, &dev_res2->list); break; } } } } /* Try updated head list with add_size added */ assign_requested_resources_sorted(head, &local_fail_head); /* All assigned with add_size? */ if (list_empty(&local_fail_head)) { /* Remove head list from realloc_head list */ list_for_each_entry(dev_res, head, list) remove_from_list(realloc_head, dev_res->res); free_list(&save_head); free_list(head); return; } /* Check failed type */ fail_type = pci_fail_res_type_mask(&local_fail_head); /* Remove not need to be released assigned res from head list etc */ list_for_each_entry_safe(dev_res, tmp_res, head, list) if (dev_res->res->parent && !pci_need_to_release(fail_type, dev_res->res)) { /* Remove it from realloc_head list */ remove_from_list(realloc_head, dev_res->res); remove_from_list(&save_head, dev_res->res); list_del(&dev_res->list); kfree(dev_res); } free_list(&local_fail_head); /* Release assigned resource */ list_for_each_entry(dev_res, head, list) if (dev_res->res->parent) release_resource(dev_res->res); /* Restore start/end/flags from saved list */ list_for_each_entry(save_res, &save_head, list) { struct resource *res = save_res->res; res->start = save_res->start; res->end = save_res->end; res->flags = save_res->flags; } free_list(&save_head); requested_and_reassign: /* Satisfy the must-have resource requests */ assign_requested_resources_sorted(head, fail_head); /* Try to satisfy any additional optional resource requests */ if (realloc_head) reassign_resources_sorted(realloc_head, head); free_list(head); } static void pdev_assign_resources_sorted(struct pci_dev *dev, struct list_head *add_head, struct list_head *fail_head) { LIST_HEAD(head); __dev_sort_resources(dev, &head); __assign_resources_sorted(&head, add_head, fail_head); } static void pbus_assign_resources_sorted(const struct pci_bus *bus, struct list_head *realloc_head, struct list_head *fail_head) { struct pci_dev *dev; LIST_HEAD(head); list_for_each_entry(dev, &bus->devices, bus_list) __dev_sort_resources(dev, &head); __assign_resources_sorted(&head, realloc_head, fail_head); } void pci_setup_cardbus(struct pci_bus *bus) { struct pci_dev *bridge = bus->self; struct resource *res; struct pci_bus_region region; pci_info(bridge, "CardBus bridge to %pR\n", &bus->busn_res); res = bus->resource[0]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->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. */ pci_info(bridge, " bridge window %pR\n", res); pci_write_config_dword(bridge, PCI_CB_IO_BASE_0, region.start); pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0, region.end); } res = bus->resource[1]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_IO) { pci_info(bridge, " bridge window %pR\n", res); pci_write_config_dword(bridge, PCI_CB_IO_BASE_1, region.start); pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1, region.end); } res = bus->resource[2]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_MEM) { pci_info(bridge, " bridge window %pR\n", res); pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0, region.start); pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0, region.end); } res = bus->resource[3]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_MEM) { pci_info(bridge, " bridge window %pR\n", res); 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 * are no I/O ports or memory behind the bridge, the 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 pci_setup_bridge_io(struct pci_dev *bridge) { struct resource *res; struct pci_bus_region region; unsigned long io_mask; u8 io_base_lo, io_limit_lo; u16 l; u32 io_upper16; io_mask = PCI_IO_RANGE_MASK; if (bridge->io_window_1k) io_mask = PCI_IO_1K_RANGE_MASK; /* Set up the top and bottom of the PCI I/O segment for this bus */ res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_IO) { pci_read_config_word(bridge, PCI_IO_BASE, &l); io_base_lo = (region.start >> 8) & io_mask; io_limit_lo = (region.end >> 8) & io_mask; l = ((u16) io_limit_lo << 8) | io_base_lo; /* Set up upper 16 bits of I/O base/limit */ io_upper16 = (region.end & 0xffff0000) | (region.start >> 16); pci_info(bridge, " bridge window %pR\n", res); } else { /* Clear upper 16 bits of I/O base/limit */ io_upper16 = 0; l = 0x00f0; } /* 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_word(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); } static void pci_setup_bridge_mmio(struct pci_dev *bridge) { struct resource *res; struct pci_bus_region region; u32 l; /* Set up the top and bottom of the PCI Memory segment for this bus */ res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_MEM) { l = (region.start >> 16) & 0xfff0; l |= region.end & 0xfff00000; pci_info(bridge, " bridge window %pR\n", res); } else { l = 0x0000fff0; } pci_write_config_dword(bridge, PCI_MEMORY_BASE, l); } static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge) { struct resource *res; struct pci_bus_region region; u32 l, bu, lu; /* * 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 */ bu = lu = 0; res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2]; pcibios_resource_to_bus(bridge->bus, ®ion, res); if (res->flags & IORESOURCE_PREFETCH) { l = (region.start >> 16) & 0xfff0; l |= region.end & 0xfff00000; if (res->flags & IORESOURCE_MEM_64) { bu = upper_32_bits(region.start); lu = upper_32_bits(region.end); } pci_info(bridge, " bridge window %pR\n", res); } else { l = 0x0000fff0; } pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l); /* Set the upper 32 bits of PREF base & limit */ pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu); pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu); } static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type) { struct pci_dev *bridge = bus->self; pci_info(bridge, "PCI bridge to %pR\n", &bus->busn_res); if (type & IORESOURCE_IO) pci_setup_bridge_io(bridge); if (type & IORESOURCE_MEM) pci_setup_bridge_mmio(bridge); if (type & IORESOURCE_PREFETCH) pci_setup_bridge_mmio_pref(bridge); pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl); } void __weak pcibios_setup_bridge(struct pci_bus *bus, unsigned long type) { } void pci_setup_bridge(struct pci_bus *bus) { unsigned long type = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH; pcibios_setup_bridge(bus, type); __pci_setup_bridge(bus, type); } int pci_claim_bridge_resource(struct pci_dev *bridge, int i) { if (i < PCI_BRIDGE_RESOURCES || i > PCI_BRIDGE_RESOURCE_END) return 0; if (pci_claim_resource(bridge, i) == 0) return 0; /* Claimed the window */ if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI) return 0; if (!pci_bus_clip_resource(bridge, i)) return -EINVAL; /* Clipping didn't change anything */ switch (i - PCI_BRIDGE_RESOURCES) { case 0: pci_setup_bridge_io(bridge); break; case 1: pci_setup_bridge_mmio(bridge); break; case 2: pci_setup_bridge_mmio_pref(bridge); break; default: return -EINVAL; } if (pci_claim_resource(bridge, i) == 0) return 0; /* Claimed a smaller window */ return -EINVAL; } /* * 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) { struct pci_dev *bridge = bus->self; struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; b_res[1].flags |= IORESOURCE_MEM; if (bridge->io_window) b_res[0].flags |= IORESOURCE_IO; if (bridge->pref_window) { b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; if (bridge->pref_64_window) { b_res[2].flags |= IORESOURCE_MEM_64; b_res[2].flags |= PCI_PREF_RANGE_TYPE_64; } } } /* * Helper function for sizing routines. Assigned resources have non-NULL * parent resource. * * Return first unassigned resource of the correct type. If there is none, * return first assigned resource of the correct type. If none of the * above, return NULL. * * Returning an assigned resource of the correct type allows the caller to * distinguish between already assigned and no resource of the correct type. */ static struct resource *find_bus_resource_of_type(struct pci_bus *bus, unsigned long type_mask, unsigned long type) { struct resource *r, *r_assigned = NULL; int i; pci_bus_for_each_resource(bus, r, i) { if (r == &ioport_resource || r == &iomem_resource) continue; if (r && (r->flags & type_mask) == type && !r->parent) return r; if (r && (r->flags & type_mask) == type && !r_assigned) r_assigned = r; } return r_assigned; } static resource_size_t calculate_iosize(resource_size_t size, resource_size_t min_size, resource_size_t size1, resource_size_t add_size, resource_size_t children_add_size, resource_size_t old_size, resource_size_t align) { if (size < min_size) size = min_size; if (old_size == 1) old_size = 0; /* * 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 = size + size1; if (size < old_size) size = old_size; size = ALIGN(max(size, add_size) + children_add_size, align); return size; } static resource_size_t calculate_memsize(resource_size_t size, resource_size_t min_size, resource_size_t add_size, resource_size_t children_add_size, resource_size_t old_size, resource_size_t align) { if (size < min_size) size = min_size; if (old_size == 1) old_size = 0; if (size < old_size) size = old_size; size = ALIGN(max(size, add_size) + children_add_size, align); return size; } resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, unsigned long type) { return 1; } #define PCI_P2P_DEFAULT_MEM_ALIGN 0x100000 /* 1MiB */ #define PCI_P2P_DEFAULT_IO_ALIGN 0x1000 /* 4KiB */ #define PCI_P2P_DEFAULT_IO_ALIGN_1K 0x400 /* 1KiB */ static resource_size_t window_alignment(struct pci_bus *bus, unsigned long type) { resource_size_t align = 1, arch_align; if (type & IORESOURCE_MEM) align = PCI_P2P_DEFAULT_MEM_ALIGN; else if (type & IORESOURCE_IO) { /* * Per spec, I/O windows are 4K-aligned, but some bridges have * an extension to support 1K alignment. */ if (bus->self->io_window_1k) align = PCI_P2P_DEFAULT_IO_ALIGN_1K; else align = PCI_P2P_DEFAULT_IO_ALIGN; } arch_align = pcibios_window_alignment(bus, type); return max(align, arch_align); } /** * pbus_size_io() - Size the I/O window of a given bus * * @bus: The bus * @min_size: The minimum I/O window that must be allocated * @add_size: Additional optional I/O window * @realloc_head: Track the additional I/O window on this list * * Sizing the I/O windows of the PCI-PCI bridge is trivial, since these * windows have 1K or 4K granularity and the I/O 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, resource_size_t min_size, resource_size_t add_size, struct list_head *realloc_head) { struct pci_dev *dev; struct resource *b_res = find_bus_resource_of_type(bus, IORESOURCE_IO, IORESOURCE_IO); resource_size_t size = 0, size0 = 0, size1 = 0; resource_size_t children_add_size = 0; resource_size_t min_align, align; if (!b_res) return; /* If resource is already assigned, nothing more to do */ if (b_res->parent) return; min_align = window_alignment(bus, IORESOURCE_IO); 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 = resource_size(r); if (r_size < 0x400) /* Might be re-aligned for ISA */ size += r_size; else size1 += r_size; align = pci_resource_alignment(dev, r); if (align > min_align) min_align = align; if (realloc_head) children_add_size += get_res_add_size(realloc_head, r); } } size0 = calculate_iosize(size, min_size, size1, 0, 0, resource_size(b_res), min_align); size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 : calculate_iosize(size, min_size, size1, add_size, children_add_size, resource_size(b_res), min_align); if (!size0 && !size1) { if (b_res->start || b_res->end) pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n", b_res, &bus->busn_res); b_res->flags = 0; return; } b_res->start = min_align; b_res->end = b_res->start + size0 - 1; b_res->flags |= IORESOURCE_STARTALIGN; if (size1 > size0 && realloc_head) { add_to_list(realloc_head, bus->self, b_res, size1-size0, min_align); pci_info(bus->self, "bridge window %pR to %pR add_size %llx\n", b_res, &bus->busn_res, (unsigned long long) size1 - size0); } } static inline resource_size_t calculate_mem_align(resource_size_t *aligns, int max_order) { resource_size_t align = 0; resource_size_t min_align = 0; int order; for (order = 0; order <= max_order; order++) { resource_size_t align1 = 1; align1 <<= (order + 20); if (!align) min_align = align1; else if (ALIGN(align + min_align, min_align) < align1) min_align = align1 >> 1; align += aligns[order]; } return min_align; } /** * pbus_size_mem() - Size the memory window of a given bus * * @bus: The bus * @mask: Mask the resource flag, then compare it with type * @type: The type of free resource from bridge * @type2: Second match type * @type3: Third match type * @min_size: The minimum memory window that must be allocated * @add_size: Additional optional memory window * @realloc_head: Track the additional memory window on this list * * Calculate the size of the bus and minimal alignment which guarantees * that all child resources fit in this size. * * Return -ENOSPC if there's no available bus resource of the desired * type. Otherwise, set the bus resource start/end to indicate the * required size, add things to realloc_head (if supplied), and return 0. */ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type, unsigned long type2, unsigned long type3, resource_size_t min_size, resource_size_t add_size, struct list_head *realloc_head) { struct pci_dev *dev; resource_size_t min_align, align, size, size0, size1; resource_size_t aligns[18]; /* Alignments from 1MB to 128GB */ int order, max_order; struct resource *b_res = find_bus_resource_of_type(bus, mask | IORESOURCE_PREFETCH, type); resource_size_t children_add_size = 0; resource_size_t children_add_align = 0; resource_size_t add_align = 0; if (!b_res) return -ENOSPC; /* If resource is already assigned, nothing more to do */ if (b_res->parent) 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]; resource_size_t r_size; if (r->parent || (r->flags & IORESOURCE_PCI_FIXED) || ((r->flags & mask) != type && (r->flags & mask) != type2 && (r->flags & mask) != type3)) continue; r_size = resource_size(r); #ifdef CONFIG_PCI_IOV /* Put SRIOV requested res to the optional list */ if (realloc_head && i >= PCI_IOV_RESOURCES && i <= PCI_IOV_RESOURCE_END) { add_align = max(pci_resource_alignment(dev, r), add_align); r->end = r->start - 1; add_to_list(realloc_head, dev, r, r_size, 0 /* Don't care */); children_add_size += r_size; continue; } #endif /* * aligns[0] is for 1MB (since bridge memory * windows are always at least 1MB aligned), so * keep "order" from being negative for smaller * resources. */ align = pci_resource_alignment(dev, r); order = __ffs(align) - 20; if (order < 0) order = 0; if (order >= ARRAY_SIZE(aligns)) { pci_warn(dev, "disabling BAR %d: %pR (bad alignment %#llx)\n", i, r, (unsigned long long) align); r->flags = 0; continue; } size += max(r_size, align); /* * Exclude ranges with size > align from calculation of * the alignment. */ if (r_size <= align) aligns[order] += align; if (order > max_order) max_order = order; if (realloc_head) { children_add_size += get_res_add_size(realloc_head, r); children_add_align = get_res_add_align(realloc_head, r); add_align = max(add_align, children_add_align); } } } min_align = calculate_mem_align(aligns, max_order); min_align = max(min_align, window_alignment(bus, b_res->flags)); size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), min_align); add_align = max(min_align, add_align); size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 : calculate_memsize(size, min_size, add_size, children_add_size, resource_size(b_res), add_align); if (!size0 && !size1) { if (b_res->start || b_res->end) pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n", b_res, &bus->busn_res); b_res->flags = 0; return 0; } b_res->start = min_align; b_res->end = size0 + min_align - 1; b_res->flags |= IORESOURCE_STARTALIGN; if (size1 > size0 && realloc_head) { add_to_list(realloc_head, bus->self, b_res, size1-size0, add_align); pci_info(bus->self, "bridge window %pR to %pR add_size %llx add_align %llx\n", b_res, &bus->busn_res, (unsigned long long) (size1 - size0), (unsigned long long) add_align); } return 0; } unsigned long pci_cardbus_resource_alignment(struct resource *res) { if (res->flags & IORESOURCE_IO) return pci_cardbus_io_size; if (res->flags & IORESOURCE_MEM) return pci_cardbus_mem_size; return 0; } static void pci_bus_size_cardbus(struct pci_bus *bus, struct list_head *realloc_head) { struct pci_dev *bridge = bus->self; struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; resource_size_t b_res_3_size = pci_cardbus_mem_size * 2; u16 ctrl; if (b_res[0].parent) goto handle_b_res_1; /* * 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 | IORESOURCE_STARTALIGN; if (realloc_head) { b_res[0].end -= pci_cardbus_io_size; add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size, pci_cardbus_io_size); } handle_b_res_1: if (b_res[1].parent) goto handle_b_res_2; 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 | IORESOURCE_STARTALIGN; if (realloc_head) { b_res[1].end -= pci_cardbus_io_size; add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size, pci_cardbus_io_size); } handle_b_res_2: /* MEM1 must not be pref MMIO */ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) { ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1; pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl); pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); } /* 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 (b_res[2].parent) goto handle_b_res_3; /* * 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 | IORESOURCE_STARTALIGN; if (realloc_head) { b_res[2].end -= pci_cardbus_mem_size; add_to_list(realloc_head, bridge, b_res+2, pci_cardbus_mem_size, pci_cardbus_mem_size); } /* Reduce that to half */ b_res_3_size = pci_cardbus_mem_size; } handle_b_res_3: if (b_res[3].parent) goto handle_done; b_res[3].start = pci_cardbus_mem_size; b_res[3].end = b_res[3].start + b_res_3_size - 1; b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN; if (realloc_head) { b_res[3].end -= b_res_3_size; add_to_list(realloc_head, bridge, b_res+3, b_res_3_size, pci_cardbus_mem_size); } handle_done: ; } void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head) { struct pci_dev *dev; unsigned long mask, prefmask, type2 = 0, type3 = 0; resource_size_t additional_io_size = 0, additional_mmio_size = 0, additional_mmio_pref_size = 0; struct resource *b_res; int ret; list_for_each_entry(dev, &bus->devices, bus_list) { struct pci_bus *b = dev->subordinate; if (!b) continue; switch (dev->hdr_type) { case PCI_HEADER_TYPE_CARDBUS: pci_bus_size_cardbus(b, realloc_head); break; case PCI_HEADER_TYPE_BRIDGE: default: __pci_bus_size_bridges(b, realloc_head); break; } } /* The root bus? */ if (pci_is_root_bus(bus)) return; switch (bus->self->hdr_type) { case PCI_HEADER_TYPE_CARDBUS: /* Don't size CardBuses yet */ break; case PCI_HEADER_TYPE_BRIDGE: pci_bridge_check_ranges(bus); if (bus->self->is_hotplug_bridge) { additional_io_size = pci_hotplug_io_size; additional_mmio_size = pci_hotplug_mmio_size; additional_mmio_pref_size = pci_hotplug_mmio_pref_size; } /* Fall through */ default: pbus_size_io(bus, realloc_head ? 0 : additional_io_size, additional_io_size, realloc_head); /* * If there's a 64-bit prefetchable MMIO window, compute * the size required to put all 64-bit prefetchable * resources in it. */ b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES]; mask = IORESOURCE_MEM; prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH; if (b_res[2].flags & IORESOURCE_MEM_64) { prefmask |= IORESOURCE_MEM_64; ret = pbus_size_mem(bus, prefmask, prefmask, prefmask, prefmask, realloc_head ? 0 : additional_mmio_pref_size, additional_mmio_pref_size, realloc_head); /* * If successful, all non-prefetchable resources * and any 32-bit prefetchable resources will go in * the non-prefetchable window. */ if (ret == 0) { mask = prefmask; type2 = prefmask & ~IORESOURCE_MEM_64; type3 = prefmask & ~IORESOURCE_PREFETCH; } } /* * If there is no 64-bit prefetchable window, compute the * size required to put all prefetchable resources in the * 32-bit prefetchable window (if there is one). */ if (!type2) { prefmask &= ~IORESOURCE_MEM_64; ret = pbus_size_mem(bus, prefmask, prefmask, prefmask, prefmask, realloc_head ? 0 : additional_mmio_pref_size, additional_mmio_pref_size, realloc_head); /* * If successful, only non-prefetchable resources * will go in the non-prefetchable window. */ if (ret == 0) mask = prefmask; else additional_mmio_size += additional_mmio_pref_size; type2 = type3 = IORESOURCE_MEM; } /* * Compute the size required to put everything else in the * non-prefetchable window. This includes: * * - all non-prefetchable resources * - 32-bit prefetchable resources if there's a 64-bit * prefetchable window or no prefetchable window at all * - 64-bit prefetchable resources if there's no prefetchable * window at all * * Note that the strategy in __pci_assign_resource() must match * that used here. Specifically, we cannot put a 32-bit * prefetchable resource in a 64-bit prefetchable window. */ pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3, realloc_head ? 0 : additional_mmio_size, additional_mmio_size, realloc_head); break; } } void pci_bus_size_bridges(struct pci_bus *bus) { __pci_bus_size_bridges(bus, NULL); } EXPORT_SYMBOL(pci_bus_size_bridges); static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r) { int i; struct resource *parent_r; unsigned long mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH; pci_bus_for_each_resource(b, parent_r, i) { if (!parent_r) continue; if ((r->flags & mask) == (parent_r->flags & mask) && resource_contains(parent_r, r)) request_resource(parent_r, r); } } /* * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they are * skipped by pbus_assign_resources_sorted(). */ static void pdev_assign_fixed_resources(struct pci_dev *dev) { int i; for (i = 0; i < PCI_NUM_RESOURCES; i++) { struct pci_bus *b; struct resource *r = &dev->resource[i]; if (r->parent || !(r->flags & IORESOURCE_PCI_FIXED) || !(r->flags & (IORESOURCE_IO | IORESOURCE_MEM))) continue; b = dev->bus; while (b && !r->parent) { assign_fixed_resource_on_bus(b, r); b = b->parent; } } } void __pci_bus_assign_resources(const struct pci_bus *bus, struct list_head *realloc_head, struct list_head *fail_head) { struct pci_bus *b; struct pci_dev *dev; pbus_assign_resources_sorted(bus, realloc_head, fail_head); list_for_each_entry(dev, &bus->devices, bus_list) { pdev_assign_fixed_resources(dev); b = dev->subordinate; if (!b) continue; __pci_bus_assign_resources(b, realloc_head, fail_head); switch (dev->hdr_type) { case PCI_HEADER_TYPE_BRIDGE: if (!pci_is_enabled(dev)) pci_setup_bridge(b); break; case PCI_HEADER_TYPE_CARDBUS: pci_setup_cardbus(b); break; default: pci_info(dev, "not setting up bridge for bus %04x:%02x\n", pci_domain_nr(b), b->number); break; } } } void pci_bus_assign_resources(const struct pci_bus *bus) { __pci_bus_assign_resources(bus, NULL, NULL); } EXPORT_SYMBOL(pci_bus_assign_resources); static void pci_claim_device_resources(struct pci_dev *dev) { int i; for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) { struct resource *r = &dev->resource[i]; if (!r->flags || r->parent) continue; pci_claim_resource(dev, i); } } static void pci_claim_bridge_resources(struct pci_dev *dev) { int i; for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) { struct resource *r = &dev->resource[i]; if (!r->flags || r->parent) continue; pci_claim_bridge_resource(dev, i); } } static void pci_bus_allocate_dev_resources(struct pci_bus *b) { struct pci_dev *dev; struct pci_bus *child; list_for_each_entry(dev, &b->devices, bus_list) { pci_claim_device_resources(dev); child = dev->subordinate; if (child) pci_bus_allocate_dev_resources(child); } } static void pci_bus_allocate_resources(struct pci_bus *b) { struct pci_bus *child; /* * Carry out a depth-first search on the PCI bus tree to allocate * bridge apertures. Read the programmed bridge bases and * recursively claim the respective bridge resources. */ if (b->self) { pci_read_bridge_bases(b); pci_claim_bridge_resources(b->self); } list_for_each_entry(child, &b->children, node) pci_bus_allocate_resources(child); } void pci_bus_claim_resources(struct pci_bus *b) { pci_bus_allocate_resources(b); pci_bus_allocate_dev_resources(b); } EXPORT_SYMBOL(pci_bus_claim_resources); static void __pci_bridge_assign_resources(const struct pci_dev *bridge, struct list_head *add_head, struct list_head *fail_head) { struct pci_bus *b; pdev_assign_resources_sorted((struct pci_dev *)bridge, add_head, fail_head); b = bridge->subordinate; if (!b) return; __pci_bus_assign_resources(b, add_head, fail_head); switch (bridge->class >> 8) { case PCI_CLASS_BRIDGE_PCI: pci_setup_bridge(b); break; case PCI_CLASS_BRIDGE_CARDBUS: pci_setup_cardbus(b); break; default: pci_info(bridge, "not setting up bridge for bus %04x:%02x\n", pci_domain_nr(b), b->number); break; } } #define PCI_RES_TYPE_MASK \ (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH |\ IORESOURCE_MEM_64) static void pci_bridge_release_resources(struct pci_bus *bus, unsigned long type) { struct pci_dev *dev = bus->self; struct resource *r; unsigned old_flags = 0; struct resource *b_res; int idx = 1; b_res = &dev->resource[PCI_BRIDGE_RESOURCES]; /* * 1. If IO port assignment fails, release bridge IO port. * 2. If non pref MMIO assignment fails, release bridge nonpref MMIO. * 3. If 64bit pref MMIO assignment fails, and bridge pref is 64bit, * release bridge pref MMIO. * 4. If pref MMIO assignment fails, and bridge pref is 32bit, * release bridge pref MMIO. * 5. If pref MMIO assignment fails, and bridge pref is not * assigned, release bridge nonpref MMIO. */ if (type & IORESOURCE_IO) idx = 0; else if (!(type & IORESOURCE_PREFETCH)) idx = 1; else if ((type & IORESOURCE_MEM_64) && (b_res[2].flags & IORESOURCE_MEM_64)) idx = 2; else if (!(b_res[2].flags & IORESOURCE_MEM_64) && (b_res[2].flags & IORESOURCE_PREFETCH)) idx = 2; else idx = 1; r = &b_res[idx]; if (!r->parent) return; /* If there are children, release them all */ release_child_resources(r); if (!release_resource(r)) { type = old_flags = r->flags & PCI_RES_TYPE_MASK; pci_info(dev, "resource %d %pR released\n", PCI_BRIDGE_RESOURCES + idx, r); /* Keep the old size */ r->end = resource_size(r) - 1; r->start = 0; r->flags = 0; /* Avoiding touch the one without PREF */ if (type & IORESOURCE_PREFETCH) type = IORESOURCE_PREFETCH; __pci_setup_bridge(bus, type); /* For next child res under same bridge */ r->flags = old_flags; } } enum release_type { leaf_only, whole_subtree, }; /* * Try to release PCI bridge resources from leaf bridge, so we can allocate * a larger window later. */ static void pci_bus_release_bridge_resources(struct pci_bus *bus, unsigned long type, enum release_type rel_type) { struct pci_dev *dev; bool is_leaf_bridge = true; list_for_each_entry(dev, &bus->devices, bus_list) { struct pci_bus *b = dev->subordinate; if (!b) continue; is_leaf_bridge = false; if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI) continue; if (rel_type == whole_subtree) pci_bus_release_bridge_resources(b, type, whole_subtree); } if (pci_is_root_bus(bus)) return; if ((bus->self->class >> 8) != PCI_CLASS_BRIDGE_PCI) return; if ((rel_type == whole_subtree) || is_leaf_bridge) pci_bridge_release_resources(bus, type); } static void pci_bus_dump_res(struct pci_bus *bus) { struct resource *res; int i; pci_bus_for_each_resource(bus, res, i) { if (!res || !res->end || !res->flags) continue; dev_info(&bus->dev, "resource %d %pR\n", i, res); } } static void pci_bus_dump_resources(struct pci_bus *bus) { struct pci_bus *b; struct pci_dev *dev; pci_bus_dump_res(bus); list_for_each_entry(dev, &bus->devices, bus_list) { b = dev->subordinate; if (!b) continue; pci_bus_dump_resources(b); } } static int pci_bus_get_depth(struct pci_bus *bus) { int depth = 0; struct pci_bus *child_bus; list_for_each_entry(child_bus, &bus->children, node) { int ret; ret = pci_bus_get_depth(child_bus); if (ret + 1 > depth) depth = ret + 1; } return depth; } /* * -1: undefined, will auto detect later * 0: disabled by user * 1: disabled by auto detect * 2: enabled by user * 3: enabled by auto detect */ enum enable_type { undefined = -1, user_disabled, auto_disabled, user_enabled, auto_enabled, }; static enum enable_type pci_realloc_enable = undefined; void __init pci_realloc_get_opt(char *str) { if (!strncmp(str, "off", 3)) pci_realloc_enable = user_disabled; else if (!strncmp(str, "on", 2)) pci_realloc_enable = user_enabled; } static bool pci_realloc_enabled(enum enable_type enable) { return enable >= user_enabled; } #if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO) static int iov_resources_unassigned(struct pci_dev *dev, void *data) { int i; bool *unassigned = data; for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES]; struct pci_bus_region region; /* Not assigned or rejected by kernel? */ if (!r->flags) continue; pcibios_resource_to_bus(dev->bus, ®ion, r); if (!region.start) { *unassigned = true; return 1; /* Return early from pci_walk_bus() */ } } return 0; } static enum enable_type pci_realloc_detect(struct pci_bus *bus, enum enable_type enable_local) { bool unassigned = false; struct pci_host_bridge *host; if (enable_local != undefined) return enable_local; host = pci_find_host_bridge(bus); if (host->preserve_config) return auto_disabled; pci_walk_bus(bus, iov_resources_unassigned, &unassigned); if (unassigned) return auto_enabled; return enable_local; } #else static enum enable_type pci_realloc_detect(struct pci_bus *bus, enum enable_type enable_local) { return enable_local; } #endif /* * First try will not touch PCI bridge res. * Second and later try will clear small leaf bridge res. * Will stop till to the max depth if can not find good one. */ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus) { LIST_HEAD(realloc_head); /* List of resources that want additional resources */ struct list_head *add_list = NULL; int tried_times = 0; enum release_type rel_type = leaf_only; LIST_HEAD(fail_head); struct pci_dev_resource *fail_res; int pci_try_num = 1; enum enable_type enable_local; /* Don't realloc if asked to do so */ enable_local = pci_realloc_detect(bus, pci_realloc_enable); if (pci_realloc_enabled(enable_local)) { int max_depth = pci_bus_get_depth(bus); pci_try_num = max_depth + 1; dev_info(&bus->dev, "max bus depth: %d pci_try_num: %d\n", max_depth, pci_try_num); } again: /* * Last try will use add_list, otherwise will try good to have as must * have, so can realloc parent bridge resource */ if (tried_times + 1 == pci_try_num) add_list = &realloc_head; /* * Depth first, calculate sizes and alignments of all subordinate buses. */ __pci_bus_size_bridges(bus, add_list); /* Depth last, allocate resources and update the hardware. */ __pci_bus_assign_resources(bus, add_list, &fail_head); if (add_list) BUG_ON(!list_empty(add_list)); tried_times++; /* Any device complain? */ if (list_empty(&fail_head)) goto dump; if (tried_times >= pci_try_num) { if (enable_local == undefined) dev_info(&bus->dev, "Some PCI device resources are unassigned, try booting with pci=realloc\n"); else if (enable_local == auto_enabled) dev_info(&bus->dev, "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n"); free_list(&fail_head); goto dump; } dev_info(&bus->dev, "No. %d try to assign unassigned res\n", tried_times + 1); /* Third times and later will not check if it is leaf */ if ((tried_times + 1) > 2) rel_type = whole_subtree; /* * Try to release leaf bridge's resources that doesn't fit resource of * child device under that bridge. */ list_for_each_entry(fail_res, &fail_head, list) pci_bus_release_bridge_resources(fail_res->dev->bus, fail_res->flags & PCI_RES_TYPE_MASK, rel_type); /* Restore size and flags */ list_for_each_entry(fail_res, &fail_head, list) { struct resource *res = fail_res->res; int idx; res->start = fail_res->start; res->end = fail_res->end; res->flags = fail_res->flags; if (pci_is_bridge(fail_res->dev)) { idx = res - &fail_res->dev->resource[0]; if (idx >= PCI_BRIDGE_RESOURCES && idx <= PCI_BRIDGE_RESOURCE_END) res->flags = 0; } } free_list(&fail_head); goto again; dump: /* Dump the resource on buses */ pci_bus_dump_resources(bus); } void __init pci_assign_unassigned_resources(void) { struct pci_bus *root_bus; list_for_each_entry(root_bus, &pci_root_buses, node) { pci_assign_unassigned_root_bus_resources(root_bus); /* Make sure the root bridge has a companion ACPI device */ if (ACPI_HANDLE(root_bus->bridge)) acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); } } static void extend_bridge_window(struct pci_dev *bridge, struct resource *res, struct list_head *add_list, resource_size_t available) { struct pci_dev_resource *dev_res; if (res->parent) return; if (resource_size(res) >= available) return; dev_res = res_to_dev_res(add_list, res); if (!dev_res) return; /* Is there room to extend the window? */ if (available - resource_size(res) <= dev_res->add_size) return; dev_res->add_size = available - resource_size(res); pci_dbg(bridge, "bridge window %pR extended by %pa\n", res, &dev_res->add_size); } static void pci_bus_distribute_available_resources(struct pci_bus *bus, struct list_head *add_list, resource_size_t available_io, resource_size_t available_mmio, resource_size_t available_mmio_pref) { resource_size_t remaining_io, remaining_mmio, remaining_mmio_pref; unsigned int normal_bridges = 0, hotplug_bridges = 0; struct resource *io_res, *mmio_res, *mmio_pref_res; struct pci_dev *dev, *bridge = bus->self; io_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0]; mmio_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1]; mmio_pref_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2]; /* * Update additional resource list (add_list) to fill all the * extra resource space available for this port except the space * calculated in __pci_bus_size_bridges() which covers all the * devices currently connected to the port and below. */ extend_bridge_window(bridge, io_res, add_list, available_io); extend_bridge_window(bridge, mmio_res, add_list, available_mmio); extend_bridge_window(bridge, mmio_pref_res, add_list, available_mmio_pref); /* * Calculate how many hotplug bridges and normal bridges there * are on this bus. We will distribute the additional available * resources between hotplug bridges. */ for_each_pci_bridge(dev, bus) { if (dev->is_hotplug_bridge) hotplug_bridges++; else normal_bridges++; } /* * There is only one bridge on the bus so it gets all available * resources which it can then distribute to the possible hotplug * bridges below. */ if (hotplug_bridges + normal_bridges == 1) { dev = list_first_entry(&bus->devices, struct pci_dev, bus_list); if (dev->subordinate) { pci_bus_distribute_available_resources(dev->subordinate, add_list, available_io, available_mmio, available_mmio_pref); } return; } if (hotplug_bridges == 0) return; /* * Calculate the total amount of extra resource space we can * pass to bridges below this one. This is basically the * extra space reduced by the minimal required space for the * non-hotplug bridges. */ remaining_io = available_io; remaining_mmio = available_mmio; remaining_mmio_pref = available_mmio_pref; for_each_pci_bridge(dev, bus) { const struct resource *res; if (dev->is_hotplug_bridge) continue; /* * Reduce the available resource space by what the * bridge and devices below it occupy. */ res = &dev->resource[PCI_BRIDGE_RESOURCES + 0]; if (!res->parent && available_io > resource_size(res)) remaining_io -= resource_size(res); res = &dev->resource[PCI_BRIDGE_RESOURCES + 1]; if (!res->parent && available_mmio > resource_size(res)) remaining_mmio -= resource_size(res); res = &dev->resource[PCI_BRIDGE_RESOURCES + 2]; if (!res->parent && available_mmio_pref > resource_size(res)) remaining_mmio_pref -= resource_size(res); } /* * Go over devices on this bus and distribute the remaining * resource space between hotplug bridges. */ for_each_pci_bridge(dev, bus) { resource_size_t align, io, mmio, mmio_pref; struct pci_bus *b; b = dev->subordinate; if (!b || !dev->is_hotplug_bridge) continue; /* * Distribute available extra resources equally between * hotplug-capable downstream ports taking alignment into * account. */ align = pci_resource_alignment(bridge, io_res); io = div64_ul(available_io, hotplug_bridges); io = min(ALIGN(io, align), remaining_io); remaining_io -= io; align = pci_resource_alignment(bridge, mmio_res); mmio = div64_ul(available_mmio, hotplug_bridges); mmio = min(ALIGN(mmio, align), remaining_mmio); remaining_mmio -= mmio; align = pci_resource_alignment(bridge, mmio_pref_res); mmio_pref = div64_ul(available_mmio_pref, hotplug_bridges); mmio_pref = min(ALIGN(mmio_pref, align), remaining_mmio_pref); remaining_mmio_pref -= mmio_pref; pci_bus_distribute_available_resources(b, add_list, io, mmio, mmio_pref); } } static void pci_bridge_distribute_available_resources(struct pci_dev *bridge, struct list_head *add_list) { resource_size_t available_io, available_mmio, available_mmio_pref; const struct resource *res; if (!bridge->is_hotplug_bridge) return; /* Take the initial extra resources from the hotplug port */ res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0]; available_io = resource_size(res); res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1]; available_mmio = resource_size(res); res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2]; available_mmio_pref = resource_size(res); pci_bus_distribute_available_resources(bridge->subordinate, add_list, available_io, available_mmio, available_mmio_pref); } void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) { struct pci_bus *parent = bridge->subordinate; /* List of resources that want additional resources */ LIST_HEAD(add_list); int tried_times = 0; LIST_HEAD(fail_head); struct pci_dev_resource *fail_res; int retval; again: __pci_bus_size_bridges(parent, &add_list); /* * Distribute remaining resources (if any) equally between hotplug * bridges below. This makes it possible to extend the hierarchy * later without running out of resources. */ pci_bridge_distribute_available_resources(bridge, &add_list); __pci_bridge_assign_resources(bridge, &add_list, &fail_head); BUG_ON(!list_empty(&add_list)); tried_times++; if (list_empty(&fail_head)) goto enable_all; if (tried_times >= 2) { /* Still fail, don't need to try more */ free_list(&fail_head); goto enable_all; } printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n", tried_times + 1); /* * Try to release leaf bridge's resources that aren't big enough * to contain child device resources. */ list_for_each_entry(fail_res, &fail_head, list) pci_bus_release_bridge_resources(fail_res->dev->bus, fail_res->flags & PCI_RES_TYPE_MASK, whole_subtree); /* Restore size and flags */ list_for_each_entry(fail_res, &fail_head, list) { struct resource *res = fail_res->res; int idx; res->start = fail_res->start; res->end = fail_res->end; res->flags = fail_res->flags; if (pci_is_bridge(fail_res->dev)) { idx = res - &fail_res->dev->resource[0]; if (idx >= PCI_BRIDGE_RESOURCES && idx <= PCI_BRIDGE_RESOURCE_END) res->flags = 0; } } free_list(&fail_head); goto again; enable_all: retval = pci_reenable_device(bridge); if (retval) pci_err(bridge, "Error reenabling bridge (%d)\n", retval); pci_set_master(bridge); } EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources); int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) { struct pci_dev_resource *dev_res; struct pci_dev *next; LIST_HEAD(saved); LIST_HEAD(added); LIST_HEAD(failed); unsigned int i; int ret; down_read(&pci_bus_sem); /* Walk to the root hub, releasing bridge BARs when possible */ next = bridge; do { bridge = next; for (i = PCI_BRIDGE_RESOURCES; i < PCI_BRIDGE_RESOURCE_END; i++) { struct resource *res = &bridge->resource[i]; if ((res->flags ^ type) & PCI_RES_TYPE_MASK) continue; /* Ignore BARs which are still in use */ if (res->child) continue; ret = add_to_list(&saved, bridge, res, 0, 0); if (ret) goto cleanup; pci_info(bridge, "BAR %d: releasing %pR\n", i, res); if (res->parent) release_resource(res); res->start = 0; res->end = 0; break; } if (i == PCI_BRIDGE_RESOURCE_END) break; next = bridge->bus ? bridge->bus->self : NULL; } while (next); if (list_empty(&saved)) { up_read(&pci_bus_sem); return -ENOENT; } __pci_bus_size_bridges(bridge->subordinate, &added); __pci_bridge_assign_resources(bridge, &added, &failed); BUG_ON(!list_empty(&added)); if (!list_empty(&failed)) { ret = -ENOSPC; goto cleanup; } list_for_each_entry(dev_res, &saved, list) { /* Skip the bridge we just assigned resources for */ if (bridge == dev_res->dev) continue; bridge = dev_res->dev; pci_setup_bridge(bridge->subordinate); } free_list(&saved); up_read(&pci_bus_sem); return 0; cleanup: /* Restore size and flags */ list_for_each_entry(dev_res, &failed, list) { struct resource *res = dev_res->res; res->start = dev_res->start; res->end = dev_res->end; res->flags = dev_res->flags; } free_list(&failed); /* Revert to the old configuration */ list_for_each_entry(dev_res, &saved, list) { struct resource *res = dev_res->res; bridge = dev_res->dev; i = res - bridge->resource; res->start = dev_res->start; res->end = dev_res->end; res->flags = dev_res->flags; pci_claim_resource(bridge, i); pci_setup_bridge(bridge->subordinate); } free_list(&saved); up_read(&pci_bus_sem); return ret; } void pci_assign_unassigned_bus_resources(struct pci_bus *bus) { struct pci_dev *dev; /* List of resources that want additional resources */ LIST_HEAD(add_list); down_read(&pci_bus_sem); for_each_pci_bridge(dev, bus) if (pci_has_subordinate(dev)) __pci_bus_size_bridges(dev->subordinate, &add_list); up_read(&pci_bus_sem); __pci_bus_assign_resources(bus, &add_list, NULL); BUG_ON(!list_empty(&add_list)); } EXPORT_SYMBOL_GPL(pci_assign_unassigned_bus_resources);