1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
|
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Quick'n'dirty IP checksum ...
*
* Copyright (C) 1998, 1999 Ralf Baechle
* Copyright (C) 1999 Silicon Graphics, Inc.
*/
#include <asm/asm.h>
#include <asm/regdef.h>
#ifdef CONFIG_64BIT
#define T0 ta0
#define T1 ta1
#define T2 ta2
#define T3 ta3
#define T4 t0
#define T7 t3
#else
#define T0 t0
#define T1 t1
#define T2 t2
#define T3 t3
#define T4 t4
#define T7 t7
#endif
#define ADDC(sum,reg) \
addu sum, reg; \
sltu v1, sum, reg; \
addu sum, v1
#define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \
lw _t0, (offset + 0x00)(src); \
lw _t1, (offset + 0x04)(src); \
lw _t2, (offset + 0x08)(src); \
lw _t3, (offset + 0x0c)(src); \
ADDC(sum, _t0); \
ADDC(sum, _t1); \
ADDC(sum, _t2); \
ADDC(sum, _t3); \
lw _t0, (offset + 0x10)(src); \
lw _t1, (offset + 0x14)(src); \
lw _t2, (offset + 0x18)(src); \
lw _t3, (offset + 0x1c)(src); \
ADDC(sum, _t0); \
ADDC(sum, _t1); \
ADDC(sum, _t2); \
ADDC(sum, _t3); \
/*
* a0: source address
* a1: length of the area to checksum
* a2: partial checksum
*/
#define src a0
#define sum v0
.text
.set noreorder
/* unknown src alignment and < 8 bytes to go */
small_csumcpy:
move a1, T2
andi T0, a1, 4
beqz T0, 1f
andi T0, a1, 2
/* Still a full word to go */
ulw T1, (src)
PTR_ADDIU src, 4
ADDC(sum, T1)
1: move T1, zero
beqz T0, 1f
andi T0, a1, 1
/* Still a halfword to go */
ulhu T1, (src)
PTR_ADDIU src, 2
1: beqz T0, 1f
sll T1, T1, 16
lbu T2, (src)
nop
#ifdef __MIPSEB__
sll T2, T2, 8
#endif
or T1, T2
1: ADDC(sum, T1)
/* fold checksum */
sll v1, sum, 16
addu sum, v1
sltu v1, sum, v1
srl sum, sum, 16
addu sum, v1
/* odd buffer alignment? */
beqz T7, 1f
nop
sll v1, sum, 8
srl sum, sum, 8
or sum, v1
andi sum, 0xffff
1:
.set reorder
/* Add the passed partial csum. */
ADDC(sum, a2)
jr ra
.set noreorder
/* ------------------------------------------------------------------------- */
.align 5
LEAF(csum_partial)
move sum, zero
move T7, zero
sltiu t8, a1, 0x8
bnez t8, small_csumcpy /* < 8 bytes to copy */
move T2, a1
beqz a1, out
andi T7, src, 0x1 /* odd buffer? */
hword_align:
beqz T7, word_align
andi t8, src, 0x2
lbu T0, (src)
LONG_SUBU a1, a1, 0x1
#ifdef __MIPSEL__
sll T0, T0, 8
#endif
ADDC(sum, T0)
PTR_ADDU src, src, 0x1
andi t8, src, 0x2
word_align:
beqz t8, dword_align
sltiu t8, a1, 56
lhu T0, (src)
LONG_SUBU a1, a1, 0x2
ADDC(sum, T0)
sltiu t8, a1, 56
PTR_ADDU src, src, 0x2
dword_align:
bnez t8, do_end_words
move t8, a1
andi t8, src, 0x4
beqz t8, qword_align
andi t8, src, 0x8
lw T0, 0x00(src)
LONG_SUBU a1, a1, 0x4
ADDC(sum, T0)
PTR_ADDU src, src, 0x4
andi t8, src, 0x8
qword_align:
beqz t8, oword_align
andi t8, src, 0x10
lw T0, 0x00(src)
lw T1, 0x04(src)
LONG_SUBU a1, a1, 0x8
ADDC(sum, T0)
ADDC(sum, T1)
PTR_ADDU src, src, 0x8
andi t8, src, 0x10
oword_align:
beqz t8, begin_movement
LONG_SRL t8, a1, 0x7
lw T3, 0x08(src)
lw T4, 0x0c(src)
lw T0, 0x00(src)
lw T1, 0x04(src)
ADDC(sum, T3)
ADDC(sum, T4)
ADDC(sum, T0)
ADDC(sum, T1)
LONG_SUBU a1, a1, 0x10
PTR_ADDU src, src, 0x10
LONG_SRL t8, a1, 0x7
begin_movement:
beqz t8, 1f
andi T2, a1, 0x40
move_128bytes:
CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
CSUM_BIGCHUNK(src, 0x20, sum, T0, T1, T3, T4)
CSUM_BIGCHUNK(src, 0x40, sum, T0, T1, T3, T4)
CSUM_BIGCHUNK(src, 0x60, sum, T0, T1, T3, T4)
LONG_SUBU t8, t8, 0x01
bnez t8, move_128bytes
PTR_ADDU src, src, 0x80
1:
beqz T2, 1f
andi T2, a1, 0x20
move_64bytes:
CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
CSUM_BIGCHUNK(src, 0x20, sum, T0, T1, T3, T4)
PTR_ADDU src, src, 0x40
1:
beqz T2, do_end_words
andi t8, a1, 0x1c
move_32bytes:
CSUM_BIGCHUNK(src, 0x00, sum, T0, T1, T3, T4)
andi t8, a1, 0x1c
PTR_ADDU src, src, 0x20
do_end_words:
beqz t8, maybe_end_cruft
LONG_SRL t8, t8, 0x2
end_words:
lw T0, (src)
LONG_SUBU t8, t8, 0x1
ADDC(sum, T0)
bnez t8, end_words
PTR_ADDU src, src, 0x4
maybe_end_cruft:
andi T2, a1, 0x3
small_memcpy:
j small_csumcpy; move a1, T2 /* XXX ??? */
beqz t2, out
move a1, T2
end_bytes:
lb T0, (src)
LONG_SUBU a1, a1, 0x1
bnez a2, end_bytes
PTR_ADDU src, src, 0x1
out:
jr ra
move v0, sum
END(csum_partial)
|
