| /* |
| * mmconfig.c - Low-level direct PCI config space access via MMCONFIG |
| * |
| * This is an 64bit optimized version that always keeps the full mmconfig |
| * space mapped. This allows lockless config space operation. |
| */ |
| |
| #include <linux/pci.h> |
| #include <linux/init.h> |
| #include <linux/acpi.h> |
| #include <linux/bitmap.h> |
| #include <asm/e820.h> |
| #include <asm/pci_x86.h> |
| |
| static char __iomem *get_virt(unsigned int seg, unsigned bus) |
| { |
| struct pci_mmcfg_region *cfg; |
| |
| list_for_each_entry(cfg, &pci_mmcfg_list, list) |
| if (cfg->segment == seg && |
| (cfg->start_bus <= bus) && |
| (cfg->end_bus >= bus)) |
| return cfg->virt; |
| |
| /* Fall back to type 0 */ |
| return NULL; |
| } |
| |
| static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn) |
| { |
| char __iomem *addr; |
| |
| addr = get_virt(seg, bus); |
| if (!addr) |
| return NULL; |
| return addr + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12)); |
| } |
| |
| static int pci_mmcfg_read(unsigned int seg, unsigned int bus, |
| unsigned int devfn, int reg, int len, u32 *value) |
| { |
| char __iomem *addr; |
| |
| /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ |
| if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) { |
| err: *value = -1; |
| return -EINVAL; |
| } |
| |
| addr = pci_dev_base(seg, bus, devfn); |
| if (!addr) |
| goto err; |
| |
| switch (len) { |
| case 1: |
| *value = mmio_config_readb(addr + reg); |
| break; |
| case 2: |
| *value = mmio_config_readw(addr + reg); |
| break; |
| case 4: |
| *value = mmio_config_readl(addr + reg); |
| break; |
| } |
| |
| return 0; |
| } |
| |
| static int pci_mmcfg_write(unsigned int seg, unsigned int bus, |
| unsigned int devfn, int reg, int len, u32 value) |
| { |
| char __iomem *addr; |
| |
| /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ |
| if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) |
| return -EINVAL; |
| |
| addr = pci_dev_base(seg, bus, devfn); |
| if (!addr) |
| return -EINVAL; |
| |
| switch (len) { |
| case 1: |
| mmio_config_writeb(addr + reg, value); |
| break; |
| case 2: |
| mmio_config_writew(addr + reg, value); |
| break; |
| case 4: |
| mmio_config_writel(addr + reg, value); |
| break; |
| } |
| |
| return 0; |
| } |
| |
| static struct pci_raw_ops pci_mmcfg = { |
| .read = pci_mmcfg_read, |
| .write = pci_mmcfg_write, |
| }; |
| |
| static void __iomem * __init mcfg_ioremap(struct pci_mmcfg_region *cfg) |
| { |
| void __iomem *addr; |
| u64 start, size; |
| int num_buses; |
| |
| start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus); |
| num_buses = cfg->end_bus - cfg->start_bus + 1; |
| size = PCI_MMCFG_BUS_OFFSET(num_buses); |
| addr = ioremap_nocache(start, size); |
| if (addr) { |
| printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n", |
| start, start + size - 1); |
| addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus); |
| } |
| return addr; |
| } |
| |
| int __init pci_mmcfg_arch_init(void) |
| { |
| struct pci_mmcfg_region *cfg; |
| |
| list_for_each_entry(cfg, &pci_mmcfg_list, list) { |
| cfg->virt = mcfg_ioremap(cfg); |
| if (!cfg->virt) { |
| printk(KERN_ERR "PCI: Cannot map mmconfig aperture for " |
| "segment %d\n", |
| cfg->segment); |
| pci_mmcfg_arch_free(); |
| return 0; |
| } |
| } |
| raw_pci_ext_ops = &pci_mmcfg; |
| return 1; |
| } |
| |
| void __init pci_mmcfg_arch_free(void) |
| { |
| struct pci_mmcfg_region *cfg; |
| |
| list_for_each_entry(cfg, &pci_mmcfg_list, list) { |
| if (cfg->virt) { |
| iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus)); |
| cfg->virt = NULL; |
| } |
| } |
| } |