[ARM] remove a common set of __virt_to_bus definitions

Let's provide an overridable default instead of having every machine
class define __virt_to_bus and __bus_to_virt to the same thing.  What
most platforms are using is bus_addr == phys_addr so such is the default.

One exception is ebsa110 which has no DMA what so ever, so the actual
definition is not important except only for proper compilation.  Also
added a comment about the special footbridge bus translation.

Let's also remove comments alluding to set_dma_addr which is not
(and should not) be commonly used.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 0 insertions, 4 deletions

diff --git a/arch/arm/mach-msm/include/mach/memory.h b/arch/arm/mach-msm/include/mach/memory.h
index 63fd47f2e62e..f4698baec976 100644
--- a/arch/arm/mach-msm/include/mach/memory.h
+++ b/arch/arm/mach-msm/include/mach/memory.h
@@ -19,9 +19,5 @@
 /* physical offset of RAM */
 #define PHYS_OFFSET             UL(0x10000000)
 
-/* bus address and physical addresses are identical */
-#define __virt_to_bus(x)        __virt_to_phys(x)
-#define __bus_to_virt(x)        __phys_to_virt(x)
-
 #endif