diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc/lib/checksum.S |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/ppc/lib/checksum.S')
-rw-r--r-- | arch/ppc/lib/checksum.S | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/arch/ppc/lib/checksum.S b/arch/ppc/lib/checksum.S new file mode 100644 index 000000000000..7874e8a80455 --- /dev/null +++ b/arch/ppc/lib/checksum.S | |||
@@ -0,0 +1,225 @@ | |||
1 | /* | ||
2 | * This file contains assembly-language implementations | ||
3 | * of IP-style 1's complement checksum routines. | ||
4 | * | ||
5 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or | ||
8 | * modify it under the terms of the GNU General Public License | ||
9 | * as published by the Free Software Foundation; either version | ||
10 | * 2 of the License, or (at your option) any later version. | ||
11 | * | ||
12 | * Severely hacked about by Paul Mackerras (paulus@cs.anu.edu.au). | ||
13 | */ | ||
14 | |||
15 | #include <linux/sys.h> | ||
16 | #include <asm/processor.h> | ||
17 | #include <asm/errno.h> | ||
18 | #include <asm/ppc_asm.h> | ||
19 | |||
20 | .text | ||
21 | |||
22 | /* | ||
23 | * ip_fast_csum(buf, len) -- Optimized for IP header | ||
24 | * len is in words and is always >= 5. | ||
25 | */ | ||
26 | _GLOBAL(ip_fast_csum) | ||
27 | lwz r0,0(r3) | ||
28 | lwzu r5,4(r3) | ||
29 | addic. r4,r4,-2 | ||
30 | addc r0,r0,r5 | ||
31 | mtctr r4 | ||
32 | blelr- | ||
33 | 1: lwzu r4,4(r3) | ||
34 | adde r0,r0,r4 | ||
35 | bdnz 1b | ||
36 | addze r0,r0 /* add in final carry */ | ||
37 | rlwinm r3,r0,16,0,31 /* fold two halves together */ | ||
38 | add r3,r0,r3 | ||
39 | not r3,r3 | ||
40 | srwi r3,r3,16 | ||
41 | blr | ||
42 | |||
43 | /* | ||
44 | * Compute checksum of TCP or UDP pseudo-header: | ||
45 | * csum_tcpudp_magic(saddr, daddr, len, proto, sum) | ||
46 | */ | ||
47 | _GLOBAL(csum_tcpudp_magic) | ||
48 | rlwimi r5,r6,16,0,15 /* put proto in upper half of len */ | ||
49 | addc r0,r3,r4 /* add 4 32-bit words together */ | ||
50 | adde r0,r0,r5 | ||
51 | adde r0,r0,r7 | ||
52 | addze r0,r0 /* add in final carry */ | ||
53 | rlwinm r3,r0,16,0,31 /* fold two halves together */ | ||
54 | add r3,r0,r3 | ||
55 | not r3,r3 | ||
56 | srwi r3,r3,16 | ||
57 | blr | ||
58 | |||
59 | /* | ||
60 | * computes the checksum of a memory block at buff, length len, | ||
61 | * and adds in "sum" (32-bit) | ||
62 | * | ||
63 | * csum_partial(buff, len, sum) | ||
64 | */ | ||
65 | _GLOBAL(csum_partial) | ||
66 | addic r0,r5,0 | ||
67 | subi r3,r3,4 | ||
68 | srwi. r6,r4,2 | ||
69 | beq 3f /* if we're doing < 4 bytes */ | ||
70 | andi. r5,r3,2 /* Align buffer to longword boundary */ | ||
71 | beq+ 1f | ||
72 | lhz r5,4(r3) /* do 2 bytes to get aligned */ | ||
73 | addi r3,r3,2 | ||
74 | subi r4,r4,2 | ||
75 | addc r0,r0,r5 | ||
76 | srwi. r6,r4,2 /* # words to do */ | ||
77 | beq 3f | ||
78 | 1: mtctr r6 | ||
79 | 2: lwzu r5,4(r3) /* the bdnz has zero overhead, so it should */ | ||
80 | adde r0,r0,r5 /* be unnecessary to unroll this loop */ | ||
81 | bdnz 2b | ||
82 | andi. r4,r4,3 | ||
83 | 3: cmpwi 0,r4,2 | ||
84 | blt+ 4f | ||
85 | lhz r5,4(r3) | ||
86 | addi r3,r3,2 | ||
87 | subi r4,r4,2 | ||
88 | adde r0,r0,r5 | ||
89 | 4: cmpwi 0,r4,1 | ||
90 | bne+ 5f | ||
91 | lbz r5,4(r3) | ||
92 | slwi r5,r5,8 /* Upper byte of word */ | ||
93 | adde r0,r0,r5 | ||
94 | 5: addze r3,r0 /* add in final carry */ | ||
95 | blr | ||
96 | |||
97 | /* | ||
98 | * Computes the checksum of a memory block at src, length len, | ||
99 | * and adds in "sum" (32-bit), while copying the block to dst. | ||
100 | * If an access exception occurs on src or dst, it stores -EFAULT | ||
101 | * to *src_err or *dst_err respectively, and (for an error on | ||
102 | * src) zeroes the rest of dst. | ||
103 | * | ||
104 | * csum_partial_copy_generic(src, dst, len, sum, src_err, dst_err) | ||
105 | */ | ||
106 | _GLOBAL(csum_partial_copy_generic) | ||
107 | addic r0,r6,0 | ||
108 | subi r3,r3,4 | ||
109 | subi r4,r4,4 | ||
110 | srwi. r6,r5,2 | ||
111 | beq 3f /* if we're doing < 4 bytes */ | ||
112 | andi. r9,r4,2 /* Align dst to longword boundary */ | ||
113 | beq+ 1f | ||
114 | 81: lhz r6,4(r3) /* do 2 bytes to get aligned */ | ||
115 | addi r3,r3,2 | ||
116 | subi r5,r5,2 | ||
117 | 91: sth r6,4(r4) | ||
118 | addi r4,r4,2 | ||
119 | addc r0,r0,r6 | ||
120 | srwi. r6,r5,2 /* # words to do */ | ||
121 | beq 3f | ||
122 | 1: srwi. r6,r5,4 /* # groups of 4 words to do */ | ||
123 | beq 10f | ||
124 | mtctr r6 | ||
125 | 71: lwz r6,4(r3) | ||
126 | 72: lwz r9,8(r3) | ||
127 | 73: lwz r10,12(r3) | ||
128 | 74: lwzu r11,16(r3) | ||
129 | adde r0,r0,r6 | ||
130 | 75: stw r6,4(r4) | ||
131 | adde r0,r0,r9 | ||
132 | 76: stw r9,8(r4) | ||
133 | adde r0,r0,r10 | ||
134 | 77: stw r10,12(r4) | ||
135 | adde r0,r0,r11 | ||
136 | 78: stwu r11,16(r4) | ||
137 | bdnz 71b | ||
138 | 10: rlwinm. r6,r5,30,30,31 /* # words left to do */ | ||
139 | beq 13f | ||
140 | mtctr r6 | ||
141 | 82: lwzu r9,4(r3) | ||
142 | 92: stwu r9,4(r4) | ||
143 | adde r0,r0,r9 | ||
144 | bdnz 82b | ||
145 | 13: andi. r5,r5,3 | ||
146 | 3: cmpwi 0,r5,2 | ||
147 | blt+ 4f | ||
148 | 83: lhz r6,4(r3) | ||
149 | addi r3,r3,2 | ||
150 | subi r5,r5,2 | ||
151 | 93: sth r6,4(r4) | ||
152 | addi r4,r4,2 | ||
153 | adde r0,r0,r6 | ||
154 | 4: cmpwi 0,r5,1 | ||
155 | bne+ 5f | ||
156 | 84: lbz r6,4(r3) | ||
157 | 94: stb r6,4(r4) | ||
158 | slwi r6,r6,8 /* Upper byte of word */ | ||
159 | adde r0,r0,r6 | ||
160 | 5: addze r3,r0 /* add in final carry */ | ||
161 | blr | ||
162 | |||
163 | /* These shouldn't go in the fixup section, since that would | ||
164 | cause the ex_table addresses to get out of order. */ | ||
165 | |||
166 | src_error_4: | ||
167 | mfctr r6 /* update # bytes remaining from ctr */ | ||
168 | rlwimi r5,r6,4,0,27 | ||
169 | b 79f | ||
170 | src_error_1: | ||
171 | li r6,0 | ||
172 | subi r5,r5,2 | ||
173 | 95: sth r6,4(r4) | ||
174 | addi r4,r4,2 | ||
175 | 79: srwi. r6,r5,2 | ||
176 | beq 3f | ||
177 | mtctr r6 | ||
178 | src_error_2: | ||
179 | li r6,0 | ||
180 | 96: stwu r6,4(r4) | ||
181 | bdnz 96b | ||
182 | 3: andi. r5,r5,3 | ||
183 | beq src_error | ||
184 | src_error_3: | ||
185 | li r6,0 | ||
186 | mtctr r5 | ||
187 | addi r4,r4,3 | ||
188 | 97: stbu r6,1(r4) | ||
189 | bdnz 97b | ||
190 | src_error: | ||
191 | cmpwi 0,r7,0 | ||
192 | beq 1f | ||
193 | li r6,-EFAULT | ||
194 | stw r6,0(r7) | ||
195 | 1: addze r3,r0 | ||
196 | blr | ||
197 | |||
198 | dst_error: | ||
199 | cmpwi 0,r8,0 | ||
200 | beq 1f | ||
201 | li r6,-EFAULT | ||
202 | stw r6,0(r8) | ||
203 | 1: addze r3,r0 | ||
204 | blr | ||
205 | |||
206 | .section __ex_table,"a" | ||
207 | .long 81b,src_error_1 | ||
208 | .long 91b,dst_error | ||
209 | .long 71b,src_error_4 | ||
210 | .long 72b,src_error_4 | ||
211 | .long 73b,src_error_4 | ||
212 | .long 74b,src_error_4 | ||
213 | .long 75b,dst_error | ||
214 | .long 76b,dst_error | ||
215 | .long 77b,dst_error | ||
216 | .long 78b,dst_error | ||
217 | .long 82b,src_error_2 | ||
218 | .long 92b,dst_error | ||
219 | .long 83b,src_error_3 | ||
220 | .long 93b,dst_error | ||
221 | .long 84b,src_error_3 | ||
222 | .long 94b,dst_error | ||
223 | .long 95b,dst_error | ||
224 | .long 96b,dst_error | ||
225 | .long 97b,dst_error | ||