2 files changed, 41 insertions, 28 deletions

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index d724736d56c8..bf476fea97ab 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -119,7 +119,8 @@ acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
         struct acpi_pci_root *root;
         
         list_for_each_entry(root, &acpi_pci_roots, node)
-                if ((root->segment == (u16) seg) && (root->bus_nr == (u16) bus))
+                if ((root->segment == (u16) seg) &&
+                    (root->secondary.start == (u16) bus))
                         return root->device->handle;
         return NULL;            
 }
@@ -153,7 +154,7 @@ EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 static acpi_status
 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 {
-        int *busnr = data;
+        struct resource *res = data;
         struct acpi_resource_address64 address;
 
         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
@@ -163,28 +164,27 @@ get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 
         acpi_resource_to_address64(resource, &address);
         if ((address.address_length > 0) &&
-            (address.resource_type == ACPI_BUS_NUMBER_RANGE))
-                *busnr = address.minimum;
+            (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
+                res->start = address.minimum;
+                res->end = address.minimum + address.address_length - 1;
+        }
 
         return AE_OK;
 }
 
 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
-                                             unsigned long long *bus)
+                                             struct resource *res)
 {
         acpi_status status;
-        int busnum;
 
-        busnum = -1;
+        res->start = -1;
         status =
             acpi_walk_resources(handle, METHOD_NAME__CRS,
-                                get_root_bridge_busnr_callback, &busnum);
+                                get_root_bridge_busnr_callback, res);
         if (ACPI_FAILURE(status))
                 return status;
-        /* Check if we really get a bus number from _CRS */
-        if (busnum == -1)
+        if (res->start == -1)
                 return AE_ERROR;
-        *bus = busnum;
         return AE_OK;
 }
 
@@ -428,34 +428,47 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
         struct acpi_device *child;
         u32 flags, base_flags;
 
+        root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
+        if (!root)
+                return -ENOMEM;
+
         segment = 0;
         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
                                        &segment);
         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
-                return -ENODEV;
+                result = -ENODEV;
+                goto end;
         }
 
         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
-        bus = 0;
-        status = try_get_root_bridge_busnr(device->handle, &bus);
+        root->secondary.flags = IORESOURCE_BUS;
+        status = try_get_root_bridge_busnr(device->handle, &root->secondary);
         if (ACPI_FAILURE(status)) {
+                /*
+                 * We need both the start and end of the downstream bus range
+                 * to interpret _CBA (MMCONFIG base address), so it really is
+                 * supposed to be in _CRS.  If we don't find it there, all we
+                 * can do is assume [_BBN-0xFF] or [0-0xFF].
+                 */
+                root->secondary.end = 0xFF;
+                printk(KERN_WARNING FW_BUG PREFIX
+                       "no secondary bus range in _CRS\n");
                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,                                               NULL, &bus);
-                if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
-                        printk(KERN_ERR PREFIX
-                             "no bus number in _CRS and can't evaluate _BBN\n");
-                        return -ENODEV;
+                if (ACPI_SUCCESS(status))
+                        root->secondary.start = bus;
+                else if (status == AE_NOT_FOUND)
+                        root->secondary.start = 0;
+                else {
+                        printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
+                        result = -ENODEV;
+                        goto end;
                 }
         }
 
-        root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
-        if (!root)
-                return -ENOMEM;
-
         INIT_LIST_HEAD(&root->node);
         root->device = device;
         root->segment = segment & 0xFFFF;
-        root->bus_nr = bus & 0xFF;
         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
         device->driver_data = root;
@@ -474,9 +487,9 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
         /* TBD: Locking */
         list_add_tail(&root->node, &acpi_pci_roots);
 
-        printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
+        printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
                acpi_device_name(device), acpi_device_bid(device),
-               root->segment, root->bus_nr);
+               root->segment, &root->secondary);
 
         /*
          * Scan the Root Bridge
@@ -485,11 +498,11 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
          * PCI namespace does not get created until this call is made (and 
          * thus the root bridge's pci_dev does not exist).
          */
-        root->bus = pci_acpi_scan_root(device, segment, bus);
+        root->bus = pci_acpi_scan_root(device, segment, root->secondary.start);
         if (!root->bus) {
                 printk(KERN_ERR PREFIX
                             "Bus %04x:%02x not present in PCI namespace\n",
-                            root->segment, root->bus_nr);
+                            root->segment, (unsigned int)root->secondary.start);
                 result = -ENODEV;
                 goto end;
         }
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 7bf83ddf82e0..baacd98e7cc6 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -373,7 +373,7 @@ struct acpi_pci_root {
         struct acpi_pci_id id;
         struct pci_bus *bus;
         u16 segment;
-        u8 bus_nr;
+        struct resource secondary;      /* downstream bus range */
 
         u32 osc_support_set;    /* _OSC state of support bits */
         u32 osc_control_set;    /* _OSC state of control bits */