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 000000000000..4095e4d66a1d
--- /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;
+}