Commit 39d3454c authored by Russell King's avatar Russell King
Browse files

ARM: footbridge: fix dc21285 PCI configuration accessors 



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: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent 5c8fe583

arch/arm/mach-footbridge/dc21285.c

+6 −6
Original line number Diff line number Diff line
@@ -65,15 +65,15 @@ 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;

		}
@@ -99,17 +99,17 @@ 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;