diff options
Diffstat (limited to 'arch/x86/pci/mmconfig_64.c')
| -rw-r--r-- | arch/x86/pci/mmconfig_64.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c new file mode 100644 index 00000000000..4095e4d66a1 --- /dev/null +++ b/arch/x86/pci/mmconfig_64.c @@ -0,0 +1,157 @@ +/* + * 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 "pci.h" + +/* Static virtual mapping of the MMCONFIG aperture */ +struct mmcfg_virt { + struct acpi_mcfg_allocation *cfg; + char __iomem *virt; +}; +static struct mmcfg_virt *pci_mmcfg_virt; + +static char __iomem *get_virt(unsigned int seg, unsigned bus) +{ + struct acpi_mcfg_allocation *cfg; + int cfg_num; + + for (cfg_num = 0; cfg_num < pci_mmcfg_config_num; cfg_num++) { + cfg = pci_mmcfg_virt[cfg_num].cfg; + if (cfg->pci_segment == seg && + (cfg->start_bus_number <= bus) && + (cfg->end_bus_number >= bus)) + return pci_mmcfg_virt[cfg_num].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; + if (seg == 0 && bus < PCI_MMCFG_MAX_CHECK_BUS && + test_bit(32*bus + PCI_SLOT(devfn), pci_mmcfg_fallback_slots)) + return NULL; + addr = get_virt(seg, bus); + if (!addr) + return NULL; + return addr + ((bus << 20) | (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))) { + *value = -1; + return -EINVAL; + } + + addr = pci_dev_base(seg, bus, devfn); + if (!addr) + return pci_conf1_read(seg,bus,devfn,reg,len,value); + + 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 pci_conf1_write(seg,bus,devfn,reg,len,value); + + 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 acpi_mcfg_allocation *cfg) +{ + void __iomem *addr; + u32 size; + + size = (cfg->end_bus_number + 1) << 20; + addr = ioremap_nocache(cfg->address, size); + if (addr) { + printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n", + cfg->address, cfg->address + size - 1); + } + return addr; +} + +int __init pci_mmcfg_arch_reachable(unsigned int seg, unsigned int bus, + unsigned int devfn) +{ + return pci_dev_base(seg, bus, devfn) != NULL; +} + +int __init pci_mmcfg_arch_init(void) +{ + int i; + pci_mmcfg_virt = kmalloc(sizeof(*pci_mmcfg_virt) * + pci_mmcfg_config_num, GFP_KERNEL); + if (pci_mmcfg_virt == NULL) { + printk(KERN_ERR "PCI: Can not allocate memory for mmconfig structures\n"); + return 0; + } + + for (i = 0; i < pci_mmcfg_config_num; ++i) { + pci_mmcfg_virt[i].cfg = &pci_mmcfg_config[i]; + pci_mmcfg_virt[i].virt = mcfg_ioremap(&pci_mmcfg_config[i]); + if (!pci_mmcfg_virt[i].virt) { + printk(KERN_ERR "PCI: Cannot map mmconfig aperture for " + "segment %d\n", + pci_mmcfg_config[i].pci_segment); + return 0; + } + } + raw_pci_ops = &pci_mmcfg; + return 1; +} |