This trivial patch changes memcpy_(to|from)io as to transfer as many 
32-bit words as possible in 32-bit accesses (in the current solution, 
the last 32-bit word was transferred as 4 byte accesses).

Signed-off-by: Albrecht Dreß <redacted>
---

diff -urpN -X linux-2.6.29.1.orig/Documentation/dontdiff 
linux-2.6.29.1.orig/arch/powerpc/kernel/io.c 
linux-2.6.29.1/arch/powerpc/kernel/io.c

--- linux-2.6.29.1.orig/arch/powerpc/kernel/io.c    2009-04-02 

22:55:27.000000000 +0200

+++ linux-2.6.29.1/arch/powerpc/kernel/io.c    2009-05-27 

11:36:09.000000000 +0200

@@ -161,7 +161,7 @@ void _memcpy_fromio(void *dest, const vo
         dest++;
         n--;
     }
-    while(n > 4) {
+    while(n >= 4) {
         *((u32 *)dest) = *((volatile u32 *)vsrc);
         eieio();
         vsrc += 4;

@@ -190,7 +190,7 @@ void _memcpy_toio(volatile void __iomem
         vdest++;
         n--;
     }
-    while(n > 4) {
+    while(n >= 4) {
         *((volatile u32 *)vdest) = *((volatile u32 *)src);
         src += 4;
         vdest += 4;


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