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authorDavid Howells <dhowells@redhat.com>2012-10-12 13:05:52 +0100
committerDavid Howells <dhowells@redhat.com>2012-10-12 13:05:52 +0100
commitcb8db5d4578ac9d996200ab59aa655344d305f5b (patch)
tree32b71e0686a2c56b9390bdc47b3e0e0ab5552212 /arch/arm/include/uapi/asm/swab.h
parentMerge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media (diff)
downloadlinux-dev-cb8db5d4578ac9d996200ab59aa655344d305f5b.tar.xz
linux-dev-cb8db5d4578ac9d996200ab59aa655344d305f5b.zip
UAPI: (Scripted) Disintegrate arch/arm/include/asm
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'arch/arm/include/uapi/asm/swab.h')
-rw-r--r--arch/arm/include/uapi/asm/swab.h53
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/arm/include/uapi/asm/swab.h b/arch/arm/include/uapi/asm/swab.h
new file mode 100644
index 000000000000..6fcb32a5c453
--- /dev/null
+++ b/arch/arm/include/uapi/asm/swab.h
@@ -0,0 +1,53 @@
+/*
+ * arch/arm/include/asm/byteorder.h
+ *
+ * ARM Endian-ness. In little endian mode, the data bus is connected such
+ * that byte accesses appear as:
+ * 0 = d0...d7, 1 = d8...d15, 2 = d16...d23, 3 = d24...d31
+ * and word accesses (data or instruction) appear as:
+ * d0...d31
+ *
+ * When in big endian mode, byte accesses appear as:
+ * 0 = d24...d31, 1 = d16...d23, 2 = d8...d15, 3 = d0...d7
+ * and word accesses (data or instruction) appear as:
+ * d0...d31
+ */
+#ifndef _UAPI__ASM_ARM_SWAB_H
+#define _UAPI__ASM_ARM_SWAB_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
+# define __SWAB_64_THRU_32__
+#endif
+
+
+#if !defined(__KERNEL__) || __LINUX_ARM_ARCH__ < 6
+static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
+{
+ __u32 t;
+
+#ifndef __thumb__
+ if (!__builtin_constant_p(x)) {
+ /*
+ * 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));
+ } else
+#endif
+ t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
+
+ 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 __arch_swab32
+
+#endif
+
+#endif /* _UAPI__ASM_ARM_SWAB_H */