Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / include / asm-arm / byteorder.h

diff --git a/include/asm-arm/byteorder.h b/include/asm-arm/byteorder.h
index d648a19..17eaf8b 100644 (file)
--- a/include/asm-arm/byteorder.h
+++ b/include/asm-arm/byteorder.h
@@ -15,9 +15,32 @@
 #ifndef __ASM_ARM_BYTEORDER_H
 #define __ASM_ARM_BYTEORDER_H
 
-
+#include <linux/compiler.h>
 #include <asm/types.h>
 
+static inline __attribute_const__ __u32 ___arch__swab32(__u32 x)
+{
+       __u32 t;
+
+       if (__builtin_constant_p(x)) {
+               t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
+       } else {
+               /*
+                * The compiler needs a bit of a hint here to always do the
+                * right thing and not screw it up to different degrees
+                * depending on the gcc version.
+                */
+               asm ("eor\t%0, %1, %1, ror #16" : "=r" (t) : "r" (x));
+       }
+       x = (x << 24) | (x >> 8);               /* mov r0,r0,ror #8      */
+       t &= ~0x00FF0000;                       /* bic r1,r1,#0x00FF0000 */
+       x ^= (t >> 8);                          /* eor r0,r0,r1,lsr #8   */
+
+       return x;
+}
+
+#define __arch__swab32(x) ___arch__swab32(x)
+
 #if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
 #  define __BYTEORDER_HAS_U64__
 #  define __SWAB_64_THRU_32__