1 files changed, 64 insertions, 1 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 8766b0e216c..712443ec6d4 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -523,6 +523,69 @@ reject:
 
 static int __initdata known_bridge;
 
+static int acpi_mcfg_64bit_base_addr __initdata = FALSE;
+
+/* The physical address of the MMCONFIG aperture.  Set from ACPI tables. */
+struct acpi_mcfg_allocation *pci_mmcfg_config;
+int pci_mmcfg_config_num;
+
+static int __init acpi_mcfg_oem_check(struct acpi_table_mcfg *mcfg)
+{
+	if (!strcmp(mcfg->header.oem_id, "SGI"))
+		acpi_mcfg_64bit_base_addr = TRUE;
+
+	return 0;
+}
+
+static int __init pci_parse_mcfg(struct acpi_table_header *header)
+{
+	struct acpi_table_mcfg *mcfg;
+	unsigned long i;
+	int config_size;
+
+	if (!header)
+		return -EINVAL;
+
+	mcfg = (struct acpi_table_mcfg *)header;
+
+	/* how many config structures do we have */
+	pci_mmcfg_config_num = 0;
+	i = header->length - sizeof(struct acpi_table_mcfg);
+	while (i >= sizeof(struct acpi_mcfg_allocation)) {
+		++pci_mmcfg_config_num;
+		i -= sizeof(struct acpi_mcfg_allocation);
+	};
+	if (pci_mmcfg_config_num == 0) {
+		printk(KERN_ERR PREFIX "MMCONFIG has no entries\n");
+		return -ENODEV;
+	}
+
+	config_size = pci_mmcfg_config_num * sizeof(*pci_mmcfg_config);
+	pci_mmcfg_config = kmalloc(config_size, GFP_KERNEL);
+	if (!pci_mmcfg_config) {
+		printk(KERN_WARNING PREFIX
+		       "No memory for MCFG config tables\n");
+		return -ENOMEM;
+	}
+
+	memcpy(pci_mmcfg_config, &mcfg[1], config_size);
+
+	acpi_mcfg_oem_check(mcfg);
+
+	for (i = 0; i < pci_mmcfg_config_num; ++i) {
+		if ((pci_mmcfg_config[i].address > 0xFFFFFFFF) &&
+		    !acpi_mcfg_64bit_base_addr) {
+			printk(KERN_ERR PREFIX
+			       "MMCONFIG not in low 4GB of memory\n");
+			kfree(pci_mmcfg_config);
+			pci_mmcfg_config_num = 0;
+			return -ENODEV;
+		}
+	}
+
+	return 0;
+}
+
 static void __init __pci_mmcfg_init(int early)
 {
 	/* MMCONFIG disabled */
@@ -543,7 +606,7 @@ static void __init __pci_mmcfg_init(int early)
 	}
 
 	if (!known_bridge)
-		acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
+		acpi_table_parse(ACPI_SIG_MCFG, pci_parse_mcfg);
 
 	pci_mmcfg_reject_broken(early);