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-rw-r--r--include/asm-xtensa/byteorder.h80
1 files changed, 0 insertions, 80 deletions
diff --git a/include/asm-xtensa/byteorder.h b/include/asm-xtensa/byteorder.h
deleted file mode 100644
index 07d10ad364d1..000000000000
--- a/include/asm-xtensa/byteorder.h
+++ /dev/null
@@ -1,80 +0,0 @@
1/*
2 * include/asm-xtensa/byteorder.h
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 2001 - 2005 Tensilica Inc.
9 */
10
11#ifndef _XTENSA_BYTEORDER_H
12#define _XTENSA_BYTEORDER_H
13
14#include <asm/types.h>
15#include <linux/compiler.h>
16
17#ifdef __XTENSA_EL__
18# define __LITTLE_ENDIAN
19#elif defined(__XTENSA_EB__)
20# define __BIG_ENDIAN
21#else
22# error processor byte order undefined!
23#endif
24
25#define __SWAB_64_THRU_32__
26
27static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
28{
29 __u32 res;
30 /* instruction sequence from Xtensa ISA release 2/2000 */
31 __asm__("ssai 8 \n\t"
32 "srli %0, %1, 16 \n\t"
33 "src %0, %0, %1 \n\t"
34 "src %0, %0, %0 \n\t"
35 "src %0, %1, %0 \n"
36 : "=&a" (res)
37 : "a" (x)
38 );
39 return res;
40}
41#define __arch_swab32 __arch_swab32
42
43static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
44{
45 /* Given that 'short' values are signed (i.e., can be negative),
46 * we cannot assume that the upper 16-bits of the register are
47 * zero. We are careful to mask values after shifting.
48 */
49
50 /* There exists an anomaly between xt-gcc and xt-xcc. xt-gcc
51 * inserts an extui instruction after putting this function inline
52 * to ensure that it uses only the least-significant 16 bits of
53 * the result. xt-xcc doesn't use an extui, but assumes the
54 * __asm__ macro follows convention that the upper 16 bits of an
55 * 'unsigned short' result are still zero. This macro doesn't
56 * follow convention; indeed, it leaves garbage in the upport 16
57 * bits of the register.
58
59 * Declaring the temporary variables 'res' and 'tmp' to be 32-bit
60 * types while the return type of the function is a 16-bit type
61 * forces both compilers to insert exactly one extui instruction
62 * (or equivalent) to mask off the upper 16 bits. */
63
64 __u32 res;
65 __u32 tmp;
66
67 __asm__("extui %1, %2, 8, 8\n\t"
68 "slli %0, %2, 8 \n\t"
69 "or %0, %0, %1 \n"
70 : "=&a" (res), "=&a" (tmp)
71 : "a" (x)
72 );
73
74 return res;
75}
76#define __arch_swab16 __arch_swab16
77
78#include <linux/byteorder.h>
79
80#endif /* _XTENSA_BYTEORDER_H */