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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-13 17:18:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-13 17:18:53 -0700
commit3d6ee36dfb2d40c72071f68173f67c728a0e19f3 (patch)
tree262130e0f3381c3d409817fdc4abec8852f10e7c /arch/arm/include/uapi/asm/swab.h
parent0b381a286e5d748b1fd80095d3dd52326819742f (diff)
parent244acb1ba3777c2eb4d33ddc246cab5419656442 (diff)
Merge branch 'late-for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM update from Russell King: "This is the final round of stuff for ARM, left until the end of the merge window to reduce the number of conflicts. This set contains the ARM part of David Howells UAPI changes, and a fix to the ordering of 'select' statements in ARM Kconfig files (see the appropriate commit for why this happened - thanks to Andrew Morton for pointing out the problem.) I've left this as long as I dare for this window to avoid conflicts, and I regenerated the config patch yesterday, posting it to our mailing list for review and testing. I have several acks which include successful test reports for it. However, today I notice we've got new conflicts with previously unseen code... though that conflict should be trivial (it's my changes vs a one liner.)" * 'late-for-linus' of git://git.linaro.org/people/rmk/linux-arm: ARM: config: make sure that platforms are ordered by option string ARM: config: sort select statements alphanumerically UAPI: (Scripted) Disintegrate arch/arm/include/asm Fix up fairly conflict in arch/arm/Kconfig (the select re-organization vs recent addition of GENERIC_KERNEL_EXECVE)
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 00000000000..6fcb32a5c45
--- /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 */