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-rw-r--r--arch/x86/pci/mmconfig_64.c157
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 0000000..4095e4d
--- /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;
+}