x86/PCI: Convert maintaining FW-assigned BIOS BAR values to use a list

This patch converts the underlying maintenance aspects of FW-assigned
BIOS BAR values from a statically allocated array within struct pci_dev
to a list of temporary, stand alone, entries.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

arch/x86/pci/i386.c

@@ -261,7 +261,8 @@ static void __init pcibios_allocate_resources(int pass)
 					idx, r, disabled, pass);
 				if (pci_claim_resource(dev, idx) < 0) {
 					/* We'll assign a new address later */
-					dev->fw_addr[idx] = r->start;
+					pcibios_save_fw_addr(dev,
+							idx, r->start);
 					r->end -= r->start;
 					r->start = 0;
 				}
@@ -307,6 +308,7 @@ static int __init pcibios_assign_resources(void)
 	}
 
 	pci_assign_unassigned_resources();
+	pcibios_fw_addr_list_del();
 
 	return 0;
 }

drivers/pci/setup-res.c

@@ -158,16 +158,34 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
 	return ret;
 }
 
+/*
+ * Generic function that returns a value indicating that the device's
+ * original BIOS BAR address was not saved and so is not available for
+ * reinstatement.
+ *
+ * Can be over-ridden by architecture specific code that implements
+ * reinstatement functionality rather than leaving it disabled when
+ * normal allocation attempts fail.
+ */
+resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
+{
+	return 0;
+}
+
 static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev, 
 		int resno, resource_size_t size)
 {
 	struct resource *root, *conflict;
-	resource_size_t start, end;
+	resource_size_t fw_addr, start, end;
 	int ret = 0;
 
+	fw_addr = pcibios_retrieve_fw_addr(dev, resno);
+	if (!fw_addr)
+		return 1;
+
 	start = res->start;
 	end = res->end;
-	res->start = dev->fw_addr[resno];
+	res->start = fw_addr;
 	res->end = res->start + size - 1;
 
 	root = pci_find_parent_resource(dev, res);
@@ -271,7 +289,7 @@ int pci_assign_resource(struct pci_dev *dev, int resno)
 	 * where firmware left it.  That at least has a chance of
 	 * working, which is better than just leaving it disabled.
 	 */
-	if (ret < 0 && dev->fw_addr[resno])
+	if (ret < 0)
 		ret = pci_revert_fw_address(res, dev, resno, size);
 
 	if (!ret) {

include/linux/pci.h

@@ -299,7 +299,6 @@ struct pci_dev {
 	 */
 	unsigned int	irq;
 	struct resource resource[DEVICE_COUNT_RESOURCE]; /* I/O and memory regions + expansion ROMs */
-	resource_size_t	fw_addr[DEVICE_COUNT_RESOURCE]; /* FW-assigned addr */
 
 	/* These fields are used by common fixups */
 	unsigned int	transparent:1;	/* Transparent PCI bridge */