[PATCH] PCI: reverse pci config space restore order

According to Intel ICH spec, there are several rules that Base Address
should be programmed before IOSE  (PCICMD register ) enabled.

For example ICH7:

12.1.3  SATA : the base address register for the bus master register
               should be programmed before this bit is set.

11.1.3:  PCICMD (USB): The base address register for USB should be
                       programmed before this bit is set.
....

To make sure kernel code follow this rule , and prevent unnecessary
confusion. I proposal this patch.

Signed-off-by: Luming Yu <luming.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index d2520451f36b7e797b596945715261964bb142fe..12286275b1c81ce3029f3dbd3e9f8127e495c4ea 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -463,7 +463,11 @@ pci_restore_state(struct pci_dev *dev)
        int i;
        int val;
 
-       for (i = 0; i < 16; i++) {
+       /*
+        * The Base Address register should be programmed before the command
+        * register(s)
+        */
+       for (i = 15; i >= 0; i--) {
                pci_read_config_dword(dev, i * 4, &val);
                if (val != dev->saved_config_space[i]) {
                        printk(KERN_DEBUG "PM: Writing back config space on "