[ARM] iop: iop3xx needs registers mapped uncached+unbuffered

Mikael Pettersson reported:

   The 2.6.28-rc kernels fail to detect PCI device 0000:00:01.0
   (the first ethernet port) on my Thecus n2100 XScale box.

   There is however still a strange "ghost" device that gets partially
   detected in 2.6.28-rc2 vanilla.

The IOP321 manual says:

  The user designates the memory region containing the OCCDR as
  non-cacheable and non-bufferable from the IntelR XScaleTM core.
  This guarantees that all load/stores to the OCCDR are only of
  DWORD quantities.

Ensure that the OCCDR is so mapped.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/arm/plat-iop/setup.c b/arch/arm/plat-iop/setup.c
index 4689db638e95..9e573e78176a 100644
--- a/arch/arm/plat-iop/setup.c
+++ b/arch/arm/plat-iop/setup.c
@@ -16,14 +16,15 @@
 #include <asm/hardware/iop3xx.h>
 
 /*
- * Standard IO mapping for all IOP3xx based systems
+ * Standard IO mapping for all IOP3xx based systems.  Note that
+ * the IOP3xx OCCDR must be mapped uncached and unbuffered.
  */
 static struct map_desc iop3xx_std_desc[] __initdata = {
          {      /* mem mapped registers */
                 .virtual        = IOP3XX_PERIPHERAL_VIRT_BASE,
                 .pfn            = __phys_to_pfn(IOP3XX_PERIPHERAL_PHYS_BASE),
                 .length         = IOP3XX_PERIPHERAL_SIZE,
-                .type           = MT_DEVICE,
+                .type           = MT_UNCACHED,
          }, {   /* PCI IO space */
                 .virtual        = IOP3XX_PCI_LOWER_IO_VA,
                 .pfn            = __phys_to_pfn(IOP3XX_PCI_LOWER_IO_PA),