ARM: footbridge: fix dc21285 PCI configuration accessors

commit 39d3454c3513840eb123b3913fda6903e45ce671 upstream.

Building with gcc 4.9.2 reveals a latent bug in the PCI accessors
for Footbridge platforms, which causes a fatal alignment fault
while accessing IO memory. Fix this by making the assembly volatile.

Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/mach-footbridge/dc21285.c

@@ -69,15 +69,15 @@ dc21285_read_config(struct pci_bus *bus, unsigned int devfn, int where,
 	if (addr)
 		switch (size) {
 		case 1:
-			asm("ldrb	%0, [%1, %2]"
+			asm volatile("ldrb	%0, [%1, %2]"
 				: "=r" (v) : "r" (addr), "r" (where) : "cc");
 			break;
 		case 2:
-			asm("ldrh	%0, [%1, %2]"
+			asm volatile("ldrh	%0, [%1, %2]"
 				: "=r" (v) : "r" (addr), "r" (where) : "cc");
 			break;
 		case 4:
-			asm("ldr	%0, [%1, %2]"
+			asm volatile("ldr	%0, [%1, %2]"
 				: "=r" (v) : "r" (addr), "r" (where) : "cc");
 			break;
 		}
@@ -103,17 +103,17 @@ dc21285_write_config(struct pci_bus *bus, unsigned int devfn, int where,
 	if (addr)
 		switch (size) {
 		case 1:
-			asm("strb	%0, [%1, %2]"
+			asm volatile("strb	%0, [%1, %2]"
 				: : "r" (value), "r" (addr), "r" (where)
 				: "cc");
 			break;
 		case 2:
-			asm("strh	%0, [%1, %2]"
+			asm volatile("strh	%0, [%1, %2]"
 				: : "r" (value), "r" (addr), "r" (where)
 				: "cc");
 			break;
 		case 4:
-			asm("str	%0, [%1, %2]"
+			asm volatile("str	%0, [%1, %2]"
 				: : "r" (value), "r" (addr), "r" (where)
 				: "cc");
 			break;