| /* |
| * Low-Level PCI Access for i386 machines |
| * |
| * Copyright 1993, 1994 Drew Eckhardt |
| * Visionary Computing |
| * (Unix and Linux consulting and custom programming) |
| * Drew@Colorado.EDU |
| * +1 (303) 786-7975 |
| * |
| * Drew's work was sponsored by: |
| * iX Multiuser Multitasking Magazine |
| * Hannover, Germany |
| * hm@ix.de |
| * |
| * Copyright 1997--2000 Martin Mares <mj@ucw.cz> |
| * |
| * For more information, please consult the following manuals (look at |
| * http://www.pcisig.com/ for how to get them): |
| * |
| * PCI BIOS Specification |
| * PCI Local Bus Specification |
| * PCI to PCI Bridge Specification |
| * PCI System Design Guide |
| * |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/export.h> |
| #include <linux/pci.h> |
| #include <linux/init.h> |
| #include <linux/ioport.h> |
| #include <linux/errno.h> |
| #include <linux/bootmem.h> |
| |
| #include <asm/pat.h> |
| #include <asm/e820.h> |
| #include <asm/pci_x86.h> |
| #include <asm/io_apic.h> |
| |
| |
| /* |
| * This list of dynamic mappings is for temporarily maintaining |
| * original BIOS BAR addresses for possible reinstatement. |
| */ |
| struct pcibios_fwaddrmap { |
| struct list_head list; |
| struct pci_dev *dev; |
| resource_size_t fw_addr[DEVICE_COUNT_RESOURCE]; |
| }; |
| |
| static LIST_HEAD(pcibios_fwaddrmappings); |
| static DEFINE_SPINLOCK(pcibios_fwaddrmap_lock); |
| static bool pcibios_fw_addr_done; |
| |
| /* Must be called with 'pcibios_fwaddrmap_lock' lock held. */ |
| static struct pcibios_fwaddrmap *pcibios_fwaddrmap_lookup(struct pci_dev *dev) |
| { |
| struct pcibios_fwaddrmap *map; |
| |
| WARN_ON_SMP(!spin_is_locked(&pcibios_fwaddrmap_lock)); |
| |
| list_for_each_entry(map, &pcibios_fwaddrmappings, list) |
| if (map->dev == dev) |
| return map; |
| |
| return NULL; |
| } |
| |
| static void |
| pcibios_save_fw_addr(struct pci_dev *dev, int idx, resource_size_t fw_addr) |
| { |
| unsigned long flags; |
| struct pcibios_fwaddrmap *map; |
| |
| if (pcibios_fw_addr_done) |
| return; |
| |
| spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags); |
| map = pcibios_fwaddrmap_lookup(dev); |
| if (!map) { |
| spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags); |
| map = kzalloc(sizeof(*map), GFP_KERNEL); |
| if (!map) |
| return; |
| |
| map->dev = pci_dev_get(dev); |
| map->fw_addr[idx] = fw_addr; |
| INIT_LIST_HEAD(&map->list); |
| |
| spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags); |
| list_add_tail(&map->list, &pcibios_fwaddrmappings); |
| } else |
| map->fw_addr[idx] = fw_addr; |
| spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags); |
| } |
| |
| resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx) |
| { |
| unsigned long flags; |
| struct pcibios_fwaddrmap *map; |
| resource_size_t fw_addr = 0; |
| |
| if (pcibios_fw_addr_done) |
| return 0; |
| |
| spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags); |
| map = pcibios_fwaddrmap_lookup(dev); |
| if (map) |
| fw_addr = map->fw_addr[idx]; |
| spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags); |
| |
| return fw_addr; |
| } |
| |
| static void __init pcibios_fw_addr_list_del(void) |
| { |
| unsigned long flags; |
| struct pcibios_fwaddrmap *entry, *next; |
| |
| spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags); |
| list_for_each_entry_safe(entry, next, &pcibios_fwaddrmappings, list) { |
| list_del(&entry->list); |
| pci_dev_put(entry->dev); |
| kfree(entry); |
| } |
| spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags); |
| pcibios_fw_addr_done = true; |
| } |
| |
| static int |
| skip_isa_ioresource_align(struct pci_dev *dev) { |
| |
| if ((pci_probe & PCI_CAN_SKIP_ISA_ALIGN) && |
| !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA)) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * We need to avoid collisions with `mirrored' VGA ports |
| * and other strange ISA hardware, so we always want the |
| * addresses to be allocated in the 0x000-0x0ff region |
| * modulo 0x400. |
| * |
| * Why? Because some silly external IO cards only decode |
| * the low 10 bits of the IO address. The 0x00-0xff region |
| * is reserved for motherboard devices that decode all 16 |
| * bits, so it's ok to allocate at, say, 0x2800-0x28ff, |
| * but we want to try to avoid allocating at 0x2900-0x2bff |
| * which might have be mirrored at 0x0100-0x03ff.. |
| */ |
| resource_size_t |
| pcibios_align_resource(void *data, const struct resource *res, |
| resource_size_t size, resource_size_t align) |
| { |
| struct pci_dev *dev = data; |
| resource_size_t start = res->start; |
| |
| if (res->flags & IORESOURCE_IO) { |
| if (skip_isa_ioresource_align(dev)) |
| return start; |
| if (start & 0x300) |
| start = (start + 0x3ff) & ~0x3ff; |
| } |
| return start; |
| } |
| EXPORT_SYMBOL(pcibios_align_resource); |
| |
| /* |
| * Handle resources of PCI devices. If the world were perfect, we could |
| * just allocate all the resource regions and do nothing more. It isn't. |
| * On the other hand, we cannot just re-allocate all devices, as it would |
| * require us to know lots of host bridge internals. So we attempt to |
| * keep as much of the original configuration as possible, but tweak it |
| * when it's found to be wrong. |
| * |
| * Known BIOS problems we have to work around: |
| * - I/O or memory regions not configured |
| * - regions configured, but not enabled in the command register |
| * - bogus I/O addresses above 64K used |
| * - expansion ROMs left enabled (this may sound harmless, but given |
| * the fact the PCI specs explicitly allow address decoders to be |
| * shared between expansion ROMs and other resource regions, it's |
| * at least dangerous) |
| * - bad resource sizes or overlaps with other regions |
| * |
| * Our solution: |
| * (1) Allocate resources for all buses behind PCI-to-PCI bridges. |
| * This gives us fixed barriers on where we can allocate. |
| * (2) Allocate resources for all enabled devices. If there is |
| * a collision, just mark the resource as unallocated. Also |
| * disable expansion ROMs during this step. |
| * (3) Try to allocate resources for disabled devices. If the |
| * resources were assigned correctly, everything goes well, |
| * if they weren't, they won't disturb allocation of other |
| * resources. |
| * (4) Assign new addresses to resources which were either |
| * not configured at all or misconfigured. If explicitly |
| * requested by the user, configure expansion ROM address |
| * as well. |
| */ |
| |
| static void pcibios_allocate_bridge_resources(struct pci_dev *dev) |
| { |
| int idx; |
| struct resource *r; |
| |
| for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) { |
| r = &dev->resource[idx]; |
| if (!r->flags) |
| continue; |
| if (r->parent) /* Already allocated */ |
| continue; |
| if (!r->start || pci_claim_resource(dev, idx) < 0) { |
| /* |
| * Something is wrong with the region. |
| * Invalidate the resource to prevent |
| * child resource allocations in this |
| * range. |
| */ |
| r->start = r->end = 0; |
| r->flags = 0; |
| } |
| } |
| } |
| |
| static void pcibios_allocate_bus_resources(struct pci_bus *bus) |
| { |
| struct pci_bus *child; |
| |
| /* Depth-First Search on bus tree */ |
| if (bus->self) |
| pcibios_allocate_bridge_resources(bus->self); |
| list_for_each_entry(child, &bus->children, node) |
| pcibios_allocate_bus_resources(child); |
| } |
| |
| struct pci_check_idx_range { |
| int start; |
| int end; |
| }; |
| |
| static void pcibios_allocate_dev_resources(struct pci_dev *dev, int pass) |
| { |
| int idx, disabled, i; |
| u16 command; |
| struct resource *r; |
| |
| struct pci_check_idx_range idx_range[] = { |
| { PCI_STD_RESOURCES, PCI_STD_RESOURCE_END }, |
| #ifdef CONFIG_PCI_IOV |
| { PCI_IOV_RESOURCES, PCI_IOV_RESOURCE_END }, |
| #endif |
| }; |
| |
| pci_read_config_word(dev, PCI_COMMAND, &command); |
| for (i = 0; i < ARRAY_SIZE(idx_range); i++) |
| for (idx = idx_range[i].start; idx <= idx_range[i].end; idx++) { |
| r = &dev->resource[idx]; |
| if (r->parent) /* Already allocated */ |
| continue; |
| if (!r->start) /* Address not assigned at all */ |
| continue; |
| if (r->flags & IORESOURCE_IO) |
| disabled = !(command & PCI_COMMAND_IO); |
| else |
| disabled = !(command & PCI_COMMAND_MEMORY); |
| if (pass == disabled) { |
| dev_dbg(&dev->dev, |
| "BAR %d: reserving %pr (d=%d, p=%d)\n", |
| idx, r, disabled, pass); |
| if (pci_claim_resource(dev, idx) < 0) { |
| /* We'll assign a new address later */ |
| pcibios_save_fw_addr(dev, |
| idx, r->start); |
| r->end -= r->start; |
| r->start = 0; |
| } |
| } |
| } |
| if (!pass) { |
| r = &dev->resource[PCI_ROM_RESOURCE]; |
| if (r->flags & IORESOURCE_ROM_ENABLE) { |
| /* Turn the ROM off, leave the resource region, |
| * but keep it unregistered. */ |
| u32 reg; |
| dev_dbg(&dev->dev, "disabling ROM %pR\n", r); |
| r->flags &= ~IORESOURCE_ROM_ENABLE; |
| pci_read_config_dword(dev, dev->rom_base_reg, ®); |
| pci_write_config_dword(dev, dev->rom_base_reg, |
| reg & ~PCI_ROM_ADDRESS_ENABLE); |
| } |
| } |
| } |
| |
| static void pcibios_allocate_resources(struct pci_bus *bus, int pass) |
| { |
| struct pci_dev *dev; |
| struct pci_bus *child; |
| |
| list_for_each_entry(dev, &bus->devices, bus_list) { |
| pcibios_allocate_dev_resources(dev, pass); |
| |
| child = dev->subordinate; |
| if (child) |
| pcibios_allocate_resources(child, pass); |
| } |
| } |
| |
| static void pcibios_allocate_dev_rom_resource(struct pci_dev *dev) |
| { |
| struct resource *r; |
| |
| /* |
| * Try to use BIOS settings for ROMs, otherwise let |
| * pci_assign_unassigned_resources() allocate the new |
| * addresses. |
| */ |
| r = &dev->resource[PCI_ROM_RESOURCE]; |
| if (!r->flags || !r->start) |
| return; |
| if (r->parent) /* Already allocated */ |
| return; |
| |
| if (pci_claim_resource(dev, PCI_ROM_RESOURCE) < 0) { |
| r->end -= r->start; |
| r->start = 0; |
| } |
| } |
| static void pcibios_allocate_rom_resources(struct pci_bus *bus) |
| { |
| struct pci_dev *dev; |
| struct pci_bus *child; |
| |
| list_for_each_entry(dev, &bus->devices, bus_list) { |
| pcibios_allocate_dev_rom_resource(dev); |
| |
| child = dev->subordinate; |
| if (child) |
| pcibios_allocate_rom_resources(child); |
| } |
| } |
| |
| static int __init pcibios_assign_resources(void) |
| { |
| struct pci_bus *bus; |
| |
| if (!(pci_probe & PCI_ASSIGN_ROMS)) |
| list_for_each_entry(bus, &pci_root_buses, node) |
| pcibios_allocate_rom_resources(bus); |
| |
| pci_assign_unassigned_resources(); |
| pcibios_fw_addr_list_del(); |
| |
| return 0; |
| } |
| |
| void pcibios_resource_survey_bus(struct pci_bus *bus) |
| { |
| dev_printk(KERN_DEBUG, &bus->dev, "Allocating resources\n"); |
| |
| pcibios_allocate_bus_resources(bus); |
| |
| pcibios_allocate_resources(bus, 0); |
| pcibios_allocate_resources(bus, 1); |
| |
| if (!(pci_probe & PCI_ASSIGN_ROMS)) |
| pcibios_allocate_rom_resources(bus); |
| } |
| |
| void __init pcibios_resource_survey(void) |
| { |
| struct pci_bus *bus; |
| |
| DBG("PCI: Allocating resources\n"); |
| |
| list_for_each_entry(bus, &pci_root_buses, node) |
| pcibios_allocate_bus_resources(bus); |
| |
| list_for_each_entry(bus, &pci_root_buses, node) |
| pcibios_allocate_resources(bus, 0); |
| list_for_each_entry(bus, &pci_root_buses, node) |
| pcibios_allocate_resources(bus, 1); |
| |
| e820_reserve_resources_late(); |
| /* |
| * Insert the IO APIC resources after PCI initialization has |
| * occurred to handle IO APICS that are mapped in on a BAR in |
| * PCI space, but before trying to assign unassigned pci res. |
| */ |
| ioapic_insert_resources(); |
| } |
| |
| /** |
| * called in fs_initcall (one below subsys_initcall), |
| * give a chance for motherboard reserve resources |
| */ |
| fs_initcall(pcibios_assign_resources); |
| |
| static const struct vm_operations_struct pci_mmap_ops = { |
| .access = generic_access_phys, |
| }; |
| |
| int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, |
| enum pci_mmap_state mmap_state, int write_combine) |
| { |
| unsigned long prot; |
| |
| /* I/O space cannot be accessed via normal processor loads and |
| * stores on this platform. |
| */ |
| if (mmap_state == pci_mmap_io) |
| return -EINVAL; |
| |
| prot = pgprot_val(vma->vm_page_prot); |
| |
| /* |
| * Return error if pat is not enabled and write_combine is requested. |
| * Caller can followup with UC MINUS request and add a WC mtrr if there |
| * is a free mtrr slot. |
| */ |
| if (!pat_enabled && write_combine) |
| return -EINVAL; |
| |
| if (pat_enabled && write_combine) |
| prot |= _PAGE_CACHE_WC; |
| else if (pat_enabled || boot_cpu_data.x86 > 3) |
| /* |
| * ioremap() and ioremap_nocache() defaults to UC MINUS for now. |
| * To avoid attribute conflicts, request UC MINUS here |
| * as well. |
| */ |
| prot |= _PAGE_CACHE_UC_MINUS; |
| |
| prot |= _PAGE_IOMAP; /* creating a mapping for IO */ |
| |
| vma->vm_page_prot = __pgprot(prot); |
| |
| if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, |
| vma->vm_end - vma->vm_start, |
| vma->vm_page_prot)) |
| return -EAGAIN; |
| |
| vma->vm_ops = &pci_mmap_ops; |
| |
| return 0; |
| } |