1 files changed, 64 insertions, 1 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 8766b0e216c5..712443ec6d43 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);