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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-08-02 05:55:55 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-08-02 16:32:35 -0400
commit4baa9922430662431231ac637adedddbb0cfb2d7 (patch)
treee8fb765ce3e41c01f33de34a0bc9494f0ae19818 /arch/arm/include/asm/byteorder.h
parentff4db0a043a5dee7180bdffd178e61cd02812c68 (diff)
[ARM] move include/asm-arm to arch/arm/include/asm
Move platform independent header files to arch/arm/include/asm, leaving those in asm/arch* and asm/plat* alone. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/byteorder.h')
-rw-r--r--arch/arm/include/asm/byteorder.h58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/arm/include/asm/byteorder.h b/arch/arm/include/asm/byteorder.h
new file mode 100644
index 000000000000..4fbfb22f65a0
--- /dev/null
+++ b/arch/arm/include/asm/byteorder.h
@@ -0,0 +1,58 @@
1/*
2 * arch/arm/include/asm/byteorder.h
3 *
4 * ARM Endian-ness. In little endian mode, the data bus is connected such
5 * that byte accesses appear as:
6 * 0 = d0...d7, 1 = d8...d15, 2 = d16...d23, 3 = d24...d31
7 * and word accesses (data or instruction) appear as:
8 * d0...d31
9 *
10 * When in big endian mode, byte accesses appear as:
11 * 0 = d24...d31, 1 = d16...d23, 2 = d8...d15, 3 = d0...d7
12 * and word accesses (data or instruction) appear as:
13 * d0...d31
14 */
15#ifndef __ASM_ARM_BYTEORDER_H
16#define __ASM_ARM_BYTEORDER_H
17
18#include <linux/compiler.h>
19#include <asm/types.h>
20
21static inline __attribute_const__ __u32 ___arch__swab32(__u32 x)
22{
23 __u32 t;
24
25#ifndef __thumb__
26 if (!__builtin_constant_p(x)) {
27 /*
28 * The compiler needs a bit of a hint here to always do the
29 * right thing and not screw it up to different degrees
30 * depending on the gcc version.
31 */
32 asm ("eor\t%0, %1, %1, ror #16" : "=r" (t) : "r" (x));
33 } else
34#endif
35 t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
36
37 x = (x << 24) | (x >> 8); /* mov r0,r0,ror #8 */
38 t &= ~0x00FF0000; /* bic r1,r1,#0x00FF0000 */
39 x ^= (t >> 8); /* eor r0,r0,r1,lsr #8 */
40
41 return x;
42}
43
44#define __arch__swab32(x) ___arch__swab32(x)
45
46#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
47# define __BYTEORDER_HAS_U64__
48# define __SWAB_64_THRU_32__
49#endif
50
51#ifdef __ARMEB__
52#include <linux/byteorder/big_endian.h>
53#else
54#include <linux/byteorder/little_endian.h>
55#endif
56
57#endif
58