1 /* 1
2 * Copyright (C) 2008-2009 Michal Simek <monst
3 * Copyright (C) 2008-2009 PetaLogix
4 * Copyright (C) 2007 John Williams
5 *
6 * Reasonably optimised generic C-code for mem
7 * This is generic C code to do efficient, ali
8 *
9 * It is based on demo code originally Copyrig
10 * http://www.embedded.com/showArticle.jhtml?a
11 *
12 * Attempts were made, unsuccessfully, to cont
13 * author of this code (Michael Morrow, Intel)
14 * copyright notice.
15 *
16 * This software has been developed by Intel C
17 * Intel specifically disclaims all warranties
18 * implied, and all liability, including conse
19 * other indirect damages, for the use of this
20 * liability for infringement of any proprieta
21 * and including the warranties of merchantabi
22 * for a particular purpose. Intel does not as
23 * responsibility for and errors which may app
24 * not any responsibility to update it.
25 */
26
27 #include <linux/export.h>
28 #include <linux/types.h>
29 #include <linux/stddef.h>
30 #include <linux/compiler.h>
31
32 #include <linux/string.h>
33
34 #ifdef CONFIG_OPT_LIB_FUNCTION
35 void *memcpy(void *v_dst, const void *v_src, _
36 {
37 const char *src = v_src;
38 char *dst = v_dst;
39
40 /* The following code tries to optimiz
41 * alignment. This will work fine if b
42 * aligned on the same boundary. Howev
43 * different boundaries shifts will be
44 * bad performance on MicroBlaze syste
45 */
46 const uint32_t *i_src;
47 uint32_t *i_dst;
48
49 if (likely(c >= 4)) {
50 unsigned value, buf_hold;
51
52 /* Align the destination to a
53 /* This is done in an endian i
54 switch ((unsigned long)dst & 3
55 case 1:
56 *dst++ = *src++;
57 --c;
58 fallthrough;
59 case 2:
60 *dst++ = *src++;
61 --c;
62 fallthrough;
63 case 3:
64 *dst++ = *src++;
65 --c;
66 }
67
68 i_dst = (void *)dst;
69
70 /* Choose a copy scheme based
71 /* alignment relative to desti
72 switch ((unsigned long)src & 3
73 case 0x0: /* Both byte o
74 i_src = (const void *
75
76 for (; c >= 4; c -= 4)
77 *i_dst++ = *i_
78
79 src = (const void *)i
80 break;
81 case 0x1: /* Unaligned -
82 /* Word align the sour
83 i_src = (const void *)
84 #ifndef __MICROBLAZEEL__
85 /* Load the holding bu
86 buf_hold = *i_src++ <<
87
88 for (; c >= 4; c -= 4)
89 value = *i_src
90 *i_dst++ = buf
91 buf_hold = val
92 }
93 #else
94 /* Load the holding bu
95 buf_hold = (*i_src++ &
96
97 for (; c >= 4; c -= 4)
98 value = *i_src
99 *i_dst++ = buf
100 buf_hold = (va
101 }
102 #endif
103 /* Realign the source
104 src = (const void *)i_
105 src -= 3;
106 break;
107 case 0x2: /* Unaligned -
108 /* Word align the sour
109 i_src = (const void *)
110 #ifndef __MICROBLAZEEL__
111 /* Load the holding bu
112 buf_hold = *i_src++ <<
113
114 for (; c >= 4; c -= 4)
115 value = *i_src
116 *i_dst++ = buf
117 buf_hold = val
118 }
119 #else
120 /* Load the holding bu
121 buf_hold = (*i_src++ &
122
123 for (; c >= 4; c -= 4)
124 value = *i_src
125 *i_dst++ = buf
126 buf_hold = (va
127 }
128 #endif
129 /* Realign the source
130 src = (const void *)i_
131 src -= 2;
132 break;
133 case 0x3: /* Unaligned -
134 /* Word align the sour
135 i_src = (const void *)
136 #ifndef __MICROBLAZEEL__
137 /* Load the holding bu
138 buf_hold = *i_src++ <<
139
140 for (; c >= 4; c -= 4)
141 value = *i_src
142 *i_dst++ = buf
143 buf_hold = val
144 }
145 #else
146 /* Load the holding bu
147 buf_hold = (*i_src++ &
148
149 for (; c >= 4; c -= 4)
150 value = *i_src
151 *i_dst++ = buf
152 buf_hold = (va
153 }
154 #endif
155 /* Realign the source
156 src = (const void *)i_
157 src -= 1;
158 break;
159 }
160 dst = (void *)i_dst;
161 }
162
163 /* Finish off any remaining bytes */
164 /* simple fast copy, ... unless a cach
165 switch (c) {
166 case 3:
167 *dst++ = *src++;
168 fallthrough;
169 case 2:
170 *dst++ = *src++;
171 fallthrough;
172 case 1:
173 *dst++ = *src++;
174 }
175
176 return v_dst;
177 }
178 EXPORT_SYMBOL(memcpy);
179 #endif /* CONFIG_OPT_LIB_FUNCTION */
180
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