ia64/linux-2.6.18-xen.hg

view include/asm-v850/unaligned.h @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 /*
2 * include/asm-v850/unaligned.h -- Unaligned memory access
3 *
4 * Copyright (C) 2001 NEC Corporation
5 * Copyright (C) 2001 Miles Bader <miles@gnu.org>
6 *
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file COPYING in the main directory of this
9 * archive for more details.
10 *
11 * This file is a copy of the arm version, include/asm-arm/unaligned.h
12 *
13 * Note that some v850 chips support unaligned access, but it seems too
14 * annoying to use.
15 */
17 #ifndef __V850_UNALIGNED_H__
18 #define __V850_UNALIGNED_H__
20 #include <asm/types.h>
22 extern int __bug_unaligned_x(void *ptr);
24 /*
25 * What is the most efficient way of loading/storing an unaligned value?
26 *
27 * That is the subject of this file. Efficiency here is defined as
28 * minimum code size with minimum register usage for the common cases.
29 * It is currently not believed that long longs are common, so we
30 * trade efficiency for the chars, shorts and longs against the long
31 * longs.
32 *
33 * Current stats with gcc 2.7.2.2 for these functions:
34 *
35 * ptrsize get: code regs put: code regs
36 * 1 1 1 1 2
37 * 2 3 2 3 2
38 * 4 7 3 7 3
39 * 8 20 6 16 6
40 *
41 * gcc 2.95.1 seems to code differently:
42 *
43 * ptrsize get: code regs put: code regs
44 * 1 1 1 1 2
45 * 2 3 2 3 2
46 * 4 7 4 7 4
47 * 8 19 8 15 6
48 *
49 * which may or may not be more efficient (depending upon whether
50 * you can afford the extra registers). Hopefully the gcc 2.95
51 * is inteligent enough to decide if it is better to use the
52 * extra register, but evidence so far seems to suggest otherwise.
53 *
54 * Unfortunately, gcc is not able to optimise the high word
55 * out of long long >> 32, or the low word from long long << 32
56 */
58 #define __get_unaligned_2(__p) \
59 (__p[0] | __p[1] << 8)
61 #define __get_unaligned_4(__p) \
62 (__p[0] | __p[1] << 8 | __p[2] << 16 | __p[3] << 24)
64 #define get_unaligned(ptr) \
65 ({ \
66 __typeof__(*(ptr)) __v; \
67 __u8 *__p = (__u8 *)(ptr); \
68 switch (sizeof(*(ptr))) { \
69 case 1: __v = *(ptr); break; \
70 case 2: __v = __get_unaligned_2(__p); break; \
71 case 4: __v = __get_unaligned_4(__p); break; \
72 case 8: { \
73 unsigned int __v1, __v2; \
74 __v2 = __get_unaligned_4((__p+4)); \
75 __v1 = __get_unaligned_4(__p); \
76 __v = ((unsigned long long)__v2 << 32 | __v1); \
77 } \
78 break; \
79 default: __v = __bug_unaligned_x(__p); break; \
80 } \
81 __v; \
82 })
85 static inline void __put_unaligned_2(__u32 __v, register __u8 *__p)
86 {
87 *__p++ = __v;
88 *__p++ = __v >> 8;
89 }
91 static inline void __put_unaligned_4(__u32 __v, register __u8 *__p)
92 {
93 __put_unaligned_2(__v >> 16, __p + 2);
94 __put_unaligned_2(__v, __p);
95 }
97 static inline void __put_unaligned_8(const unsigned long long __v, register __u8 *__p)
98 {
99 /*
100 * tradeoff: 8 bytes of stack for all unaligned puts (2
101 * instructions), or an extra register in the long long
102 * case - go for the extra register.
103 */
104 __put_unaligned_4(__v >> 32, __p+4);
105 __put_unaligned_4(__v, __p);
106 }
108 /*
109 * Try to store an unaligned value as efficiently as possible.
110 */
111 #define put_unaligned(val,ptr) \
112 ({ \
113 switch (sizeof(*(ptr))) { \
114 case 1: \
115 *(ptr) = (val); \
116 break; \
117 case 2: __put_unaligned_2((val),(__u8 *)(ptr)); \
118 break; \
119 case 4: __put_unaligned_4((val),(__u8 *)(ptr)); \
120 break; \
121 case 8: __put_unaligned_8((val),(__u8 *)(ptr)); \
122 break; \
123 default: __bug_unaligned_x(ptr); \
124 break; \
125 } \
126 (void) 0; \
127 })
130 #endif /* __V850_UNALIGNED_H__ */