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Diffstat (limited to 'arch/mips/lib/csum_partial.S')
-rw-r--r-- | arch/mips/lib/csum_partial.S | 754 |
1 files changed, 754 insertions, 0 deletions
diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S new file mode 100644 index 000000000..a46db0807 --- /dev/null +++ b/arch/mips/lib/csum_partial.S | |||
@@ -0,0 +1,754 @@ | |||
1 | /* | ||
2 | * This file is subject to the terms and conditions of the GNU General Public | ||
3 | * License. See the file "COPYING" in the main directory of this archive | ||
4 | * for more details. | ||
5 | * | ||
6 | * Quick'n'dirty IP checksum ... | ||
7 | * | ||
8 | * Copyright (C) 1998, 1999 Ralf Baechle | ||
9 | * Copyright (C) 1999 Silicon Graphics, Inc. | ||
10 | * Copyright (C) 2007 Maciej W. Rozycki | ||
11 | * Copyright (C) 2014 Imagination Technologies Ltd. | ||
12 | */ | ||
13 | #include <linux/errno.h> | ||
14 | #include <asm/asm.h> | ||
15 | #include <asm/asm-offsets.h> | ||
16 | #include <asm/export.h> | ||
17 | #include <asm/regdef.h> | ||
18 | |||
19 | #ifdef CONFIG_64BIT | ||
20 | /* | ||
21 | * As we are sharing code base with the mips32 tree (which use the o32 ABI | ||
22 | * register definitions). We need to redefine the register definitions from | ||
23 | * the n64 ABI register naming to the o32 ABI register naming. | ||
24 | */ | ||
25 | #undef t0 | ||
26 | #undef t1 | ||
27 | #undef t2 | ||
28 | #undef t3 | ||
29 | #define t0 $8 | ||
30 | #define t1 $9 | ||
31 | #define t2 $10 | ||
32 | #define t3 $11 | ||
33 | #define t4 $12 | ||
34 | #define t5 $13 | ||
35 | #define t6 $14 | ||
36 | #define t7 $15 | ||
37 | |||
38 | #define USE_DOUBLE | ||
39 | #endif | ||
40 | |||
41 | #ifdef USE_DOUBLE | ||
42 | |||
43 | #define LOAD ld | ||
44 | #define LOAD32 lwu | ||
45 | #define ADD daddu | ||
46 | #define NBYTES 8 | ||
47 | |||
48 | #else | ||
49 | |||
50 | #define LOAD lw | ||
51 | #define LOAD32 lw | ||
52 | #define ADD addu | ||
53 | #define NBYTES 4 | ||
54 | |||
55 | #endif /* USE_DOUBLE */ | ||
56 | |||
57 | #define UNIT(unit) ((unit)*NBYTES) | ||
58 | |||
59 | #define ADDC(sum,reg) \ | ||
60 | .set push; \ | ||
61 | .set noat; \ | ||
62 | ADD sum, reg; \ | ||
63 | sltu v1, sum, reg; \ | ||
64 | ADD sum, v1; \ | ||
65 | .set pop | ||
66 | |||
67 | #define ADDC32(sum,reg) \ | ||
68 | .set push; \ | ||
69 | .set noat; \ | ||
70 | addu sum, reg; \ | ||
71 | sltu v1, sum, reg; \ | ||
72 | addu sum, v1; \ | ||
73 | .set pop | ||
74 | |||
75 | #define CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3) \ | ||
76 | LOAD _t0, (offset + UNIT(0))(src); \ | ||
77 | LOAD _t1, (offset + UNIT(1))(src); \ | ||
78 | LOAD _t2, (offset + UNIT(2))(src); \ | ||
79 | LOAD _t3, (offset + UNIT(3))(src); \ | ||
80 | ADDC(_t0, _t1); \ | ||
81 | ADDC(_t2, _t3); \ | ||
82 | ADDC(sum, _t0); \ | ||
83 | ADDC(sum, _t2) | ||
84 | |||
85 | #ifdef USE_DOUBLE | ||
86 | #define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \ | ||
87 | CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3) | ||
88 | #else | ||
89 | #define CSUM_BIGCHUNK(src, offset, sum, _t0, _t1, _t2, _t3) \ | ||
90 | CSUM_BIGCHUNK1(src, offset, sum, _t0, _t1, _t2, _t3); \ | ||
91 | CSUM_BIGCHUNK1(src, offset + 0x10, sum, _t0, _t1, _t2, _t3) | ||
92 | #endif | ||
93 | |||
94 | /* | ||
95 | * a0: source address | ||
96 | * a1: length of the area to checksum | ||
97 | * a2: partial checksum | ||
98 | */ | ||
99 | |||
100 | #define src a0 | ||
101 | #define sum v0 | ||
102 | |||
103 | .text | ||
104 | .set noreorder | ||
105 | .align 5 | ||
106 | LEAF(csum_partial) | ||
107 | EXPORT_SYMBOL(csum_partial) | ||
108 | move sum, zero | ||
109 | move t7, zero | ||
110 | |||
111 | sltiu t8, a1, 0x8 | ||
112 | bnez t8, .Lsmall_csumcpy /* < 8 bytes to copy */ | ||
113 | move t2, a1 | ||
114 | |||
115 | andi t7, src, 0x1 /* odd buffer? */ | ||
116 | |||
117 | .Lhword_align: | ||
118 | beqz t7, .Lword_align | ||
119 | andi t8, src, 0x2 | ||
120 | |||
121 | lbu t0, (src) | ||
122 | LONG_SUBU a1, a1, 0x1 | ||
123 | #ifdef __MIPSEL__ | ||
124 | sll t0, t0, 8 | ||
125 | #endif | ||
126 | ADDC(sum, t0) | ||
127 | PTR_ADDU src, src, 0x1 | ||
128 | andi t8, src, 0x2 | ||
129 | |||
130 | .Lword_align: | ||
131 | beqz t8, .Ldword_align | ||
132 | sltiu t8, a1, 56 | ||
133 | |||
134 | lhu t0, (src) | ||
135 | LONG_SUBU a1, a1, 0x2 | ||
136 | ADDC(sum, t0) | ||
137 | sltiu t8, a1, 56 | ||
138 | PTR_ADDU src, src, 0x2 | ||
139 | |||
140 | .Ldword_align: | ||
141 | bnez t8, .Ldo_end_words | ||
142 | move t8, a1 | ||
143 | |||
144 | andi t8, src, 0x4 | ||
145 | beqz t8, .Lqword_align | ||
146 | andi t8, src, 0x8 | ||
147 | |||
148 | LOAD32 t0, 0x00(src) | ||
149 | LONG_SUBU a1, a1, 0x4 | ||
150 | ADDC(sum, t0) | ||
151 | PTR_ADDU src, src, 0x4 | ||
152 | andi t8, src, 0x8 | ||
153 | |||
154 | .Lqword_align: | ||
155 | beqz t8, .Loword_align | ||
156 | andi t8, src, 0x10 | ||
157 | |||
158 | #ifdef USE_DOUBLE | ||
159 | ld t0, 0x00(src) | ||
160 | LONG_SUBU a1, a1, 0x8 | ||
161 | ADDC(sum, t0) | ||
162 | #else | ||
163 | lw t0, 0x00(src) | ||
164 | lw t1, 0x04(src) | ||
165 | LONG_SUBU a1, a1, 0x8 | ||
166 | ADDC(sum, t0) | ||
167 | ADDC(sum, t1) | ||
168 | #endif | ||
169 | PTR_ADDU src, src, 0x8 | ||
170 | andi t8, src, 0x10 | ||
171 | |||
172 | .Loword_align: | ||
173 | beqz t8, .Lbegin_movement | ||
174 | LONG_SRL t8, a1, 0x7 | ||
175 | |||
176 | #ifdef USE_DOUBLE | ||
177 | ld t0, 0x00(src) | ||
178 | ld t1, 0x08(src) | ||
179 | ADDC(sum, t0) | ||
180 | ADDC(sum, t1) | ||
181 | #else | ||
182 | CSUM_BIGCHUNK1(src, 0x00, sum, t0, t1, t3, t4) | ||
183 | #endif | ||
184 | LONG_SUBU a1, a1, 0x10 | ||
185 | PTR_ADDU src, src, 0x10 | ||
186 | LONG_SRL t8, a1, 0x7 | ||
187 | |||
188 | .Lbegin_movement: | ||
189 | beqz t8, 1f | ||
190 | andi t2, a1, 0x40 | ||
191 | |||
192 | .Lmove_128bytes: | ||
193 | CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) | ||
194 | CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4) | ||
195 | CSUM_BIGCHUNK(src, 0x40, sum, t0, t1, t3, t4) | ||
196 | CSUM_BIGCHUNK(src, 0x60, sum, t0, t1, t3, t4) | ||
197 | LONG_SUBU t8, t8, 0x01 | ||
198 | .set reorder /* DADDI_WAR */ | ||
199 | PTR_ADDU src, src, 0x80 | ||
200 | bnez t8, .Lmove_128bytes | ||
201 | .set noreorder | ||
202 | |||
203 | 1: | ||
204 | beqz t2, 1f | ||
205 | andi t2, a1, 0x20 | ||
206 | |||
207 | .Lmove_64bytes: | ||
208 | CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) | ||
209 | CSUM_BIGCHUNK(src, 0x20, sum, t0, t1, t3, t4) | ||
210 | PTR_ADDU src, src, 0x40 | ||
211 | |||
212 | 1: | ||
213 | beqz t2, .Ldo_end_words | ||
214 | andi t8, a1, 0x1c | ||
215 | |||
216 | .Lmove_32bytes: | ||
217 | CSUM_BIGCHUNK(src, 0x00, sum, t0, t1, t3, t4) | ||
218 | andi t8, a1, 0x1c | ||
219 | PTR_ADDU src, src, 0x20 | ||
220 | |||
221 | .Ldo_end_words: | ||
222 | beqz t8, .Lsmall_csumcpy | ||
223 | andi t2, a1, 0x3 | ||
224 | LONG_SRL t8, t8, 0x2 | ||
225 | |||
226 | .Lend_words: | ||
227 | LOAD32 t0, (src) | ||
228 | LONG_SUBU t8, t8, 0x1 | ||
229 | ADDC(sum, t0) | ||
230 | .set reorder /* DADDI_WAR */ | ||
231 | PTR_ADDU src, src, 0x4 | ||
232 | bnez t8, .Lend_words | ||
233 | .set noreorder | ||
234 | |||
235 | /* unknown src alignment and < 8 bytes to go */ | ||
236 | .Lsmall_csumcpy: | ||
237 | move a1, t2 | ||
238 | |||
239 | andi t0, a1, 4 | ||
240 | beqz t0, 1f | ||
241 | andi t0, a1, 2 | ||
242 | |||
243 | /* Still a full word to go */ | ||
244 | ulw t1, (src) | ||
245 | PTR_ADDIU src, 4 | ||
246 | #ifdef USE_DOUBLE | ||
247 | dsll t1, t1, 32 /* clear lower 32bit */ | ||
248 | #endif | ||
249 | ADDC(sum, t1) | ||
250 | |||
251 | 1: move t1, zero | ||
252 | beqz t0, 1f | ||
253 | andi t0, a1, 1 | ||
254 | |||
255 | /* Still a halfword to go */ | ||
256 | ulhu t1, (src) | ||
257 | PTR_ADDIU src, 2 | ||
258 | |||
259 | 1: beqz t0, 1f | ||
260 | sll t1, t1, 16 | ||
261 | |||
262 | lbu t2, (src) | ||
263 | nop | ||
264 | |||
265 | #ifdef __MIPSEB__ | ||
266 | sll t2, t2, 8 | ||
267 | #endif | ||
268 | or t1, t2 | ||
269 | |||
270 | 1: ADDC(sum, t1) | ||
271 | |||
272 | /* fold checksum */ | ||
273 | #ifdef USE_DOUBLE | ||
274 | dsll32 v1, sum, 0 | ||
275 | daddu sum, v1 | ||
276 | sltu v1, sum, v1 | ||
277 | dsra32 sum, sum, 0 | ||
278 | addu sum, v1 | ||
279 | #endif | ||
280 | |||
281 | /* odd buffer alignment? */ | ||
282 | #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR5) || \ | ||
283 | defined(CONFIG_CPU_LOONGSON64) | ||
284 | .set push | ||
285 | .set arch=mips32r2 | ||
286 | wsbh v1, sum | ||
287 | movn sum, v1, t7 | ||
288 | .set pop | ||
289 | #else | ||
290 | beqz t7, 1f /* odd buffer alignment? */ | ||
291 | lui v1, 0x00ff | ||
292 | addu v1, 0x00ff | ||
293 | and t0, sum, v1 | ||
294 | sll t0, t0, 8 | ||
295 | srl sum, sum, 8 | ||
296 | and sum, sum, v1 | ||
297 | or sum, sum, t0 | ||
298 | 1: | ||
299 | #endif | ||
300 | .set reorder | ||
301 | /* Add the passed partial csum. */ | ||
302 | ADDC32(sum, a2) | ||
303 | jr ra | ||
304 | .set noreorder | ||
305 | END(csum_partial) | ||
306 | |||
307 | |||
308 | /* | ||
309 | * checksum and copy routines based on memcpy.S | ||
310 | * | ||
311 | * csum_partial_copy_nocheck(src, dst, len) | ||
312 | * __csum_partial_copy_kernel(src, dst, len) | ||
313 | * | ||
314 | * See "Spec" in memcpy.S for details. Unlike __copy_user, all | ||
315 | * function in this file use the standard calling convention. | ||
316 | */ | ||
317 | |||
318 | #define src a0 | ||
319 | #define dst a1 | ||
320 | #define len a2 | ||
321 | #define sum v0 | ||
322 | #define odd t8 | ||
323 | |||
324 | /* | ||
325 | * All exception handlers simply return 0. | ||
326 | */ | ||
327 | |||
328 | /* Instruction type */ | ||
329 | #define LD_INSN 1 | ||
330 | #define ST_INSN 2 | ||
331 | #define LEGACY_MODE 1 | ||
332 | #define EVA_MODE 2 | ||
333 | #define USEROP 1 | ||
334 | #define KERNELOP 2 | ||
335 | |||
336 | /* | ||
337 | * Wrapper to add an entry in the exception table | ||
338 | * in case the insn causes a memory exception. | ||
339 | * Arguments: | ||
340 | * insn : Load/store instruction | ||
341 | * type : Instruction type | ||
342 | * reg : Register | ||
343 | * addr : Address | ||
344 | * handler : Exception handler | ||
345 | */ | ||
346 | #define EXC(insn, type, reg, addr) \ | ||
347 | .if \mode == LEGACY_MODE; \ | ||
348 | 9: insn reg, addr; \ | ||
349 | .section __ex_table,"a"; \ | ||
350 | PTR 9b, .L_exc; \ | ||
351 | .previous; \ | ||
352 | /* This is enabled in EVA mode */ \ | ||
353 | .else; \ | ||
354 | /* If loading from user or storing to user */ \ | ||
355 | .if ((\from == USEROP) && (type == LD_INSN)) || \ | ||
356 | ((\to == USEROP) && (type == ST_INSN)); \ | ||
357 | 9: __BUILD_EVA_INSN(insn##e, reg, addr); \ | ||
358 | .section __ex_table,"a"; \ | ||
359 | PTR 9b, .L_exc; \ | ||
360 | .previous; \ | ||
361 | .else; \ | ||
362 | /* EVA without exception */ \ | ||
363 | insn reg, addr; \ | ||
364 | .endif; \ | ||
365 | .endif | ||
366 | |||
367 | #undef LOAD | ||
368 | |||
369 | #ifdef USE_DOUBLE | ||
370 | |||
371 | #define LOADK ld /* No exception */ | ||
372 | #define LOAD(reg, addr) EXC(ld, LD_INSN, reg, addr) | ||
373 | #define LOADBU(reg, addr) EXC(lbu, LD_INSN, reg, addr) | ||
374 | #define LOADL(reg, addr) EXC(ldl, LD_INSN, reg, addr) | ||
375 | #define LOADR(reg, addr) EXC(ldr, LD_INSN, reg, addr) | ||
376 | #define STOREB(reg, addr) EXC(sb, ST_INSN, reg, addr) | ||
377 | #define STOREL(reg, addr) EXC(sdl, ST_INSN, reg, addr) | ||
378 | #define STORER(reg, addr) EXC(sdr, ST_INSN, reg, addr) | ||
379 | #define STORE(reg, addr) EXC(sd, ST_INSN, reg, addr) | ||
380 | #define ADD daddu | ||
381 | #define SUB dsubu | ||
382 | #define SRL dsrl | ||
383 | #define SLL dsll | ||
384 | #define SLLV dsllv | ||
385 | #define SRLV dsrlv | ||
386 | #define NBYTES 8 | ||
387 | #define LOG_NBYTES 3 | ||
388 | |||
389 | #else | ||
390 | |||
391 | #define LOADK lw /* No exception */ | ||
392 | #define LOAD(reg, addr) EXC(lw, LD_INSN, reg, addr) | ||
393 | #define LOADBU(reg, addr) EXC(lbu, LD_INSN, reg, addr) | ||
394 | #define LOADL(reg, addr) EXC(lwl, LD_INSN, reg, addr) | ||
395 | #define LOADR(reg, addr) EXC(lwr, LD_INSN, reg, addr) | ||
396 | #define STOREB(reg, addr) EXC(sb, ST_INSN, reg, addr) | ||
397 | #define STOREL(reg, addr) EXC(swl, ST_INSN, reg, addr) | ||
398 | #define STORER(reg, addr) EXC(swr, ST_INSN, reg, addr) | ||
399 | #define STORE(reg, addr) EXC(sw, ST_INSN, reg, addr) | ||
400 | #define ADD addu | ||
401 | #define SUB subu | ||
402 | #define SRL srl | ||
403 | #define SLL sll | ||
404 | #define SLLV sllv | ||
405 | #define SRLV srlv | ||
406 | #define NBYTES 4 | ||
407 | #define LOG_NBYTES 2 | ||
408 | |||
409 | #endif /* USE_DOUBLE */ | ||
410 | |||
411 | #ifdef CONFIG_CPU_LITTLE_ENDIAN | ||
412 | #define LDFIRST LOADR | ||
413 | #define LDREST LOADL | ||
414 | #define STFIRST STORER | ||
415 | #define STREST STOREL | ||
416 | #define SHIFT_DISCARD SLLV | ||
417 | #define SHIFT_DISCARD_REVERT SRLV | ||
418 | #else | ||
419 | #define LDFIRST LOADL | ||
420 | #define LDREST LOADR | ||
421 | #define STFIRST STOREL | ||
422 | #define STREST STORER | ||
423 | #define SHIFT_DISCARD SRLV | ||
424 | #define SHIFT_DISCARD_REVERT SLLV | ||
425 | #endif | ||
426 | |||
427 | #define FIRST(unit) ((unit)*NBYTES) | ||
428 | #define REST(unit) (FIRST(unit)+NBYTES-1) | ||
429 | |||
430 | #define ADDRMASK (NBYTES-1) | ||
431 | |||
432 | #ifndef CONFIG_CPU_DADDI_WORKAROUNDS | ||
433 | .set noat | ||
434 | #else | ||
435 | .set at=v1 | ||
436 | #endif | ||
437 | |||
438 | .macro __BUILD_CSUM_PARTIAL_COPY_USER mode, from, to | ||
439 | |||
440 | li sum, -1 | ||
441 | move odd, zero | ||
442 | /* | ||
443 | * Note: dst & src may be unaligned, len may be 0 | ||
444 | * Temps | ||
445 | */ | ||
446 | /* | ||
447 | * The "issue break"s below are very approximate. | ||
448 | * Issue delays for dcache fills will perturb the schedule, as will | ||
449 | * load queue full replay traps, etc. | ||
450 | * | ||
451 | * If len < NBYTES use byte operations. | ||
452 | */ | ||
453 | sltu t2, len, NBYTES | ||
454 | and t1, dst, ADDRMASK | ||
455 | bnez t2, .Lcopy_bytes_checklen\@ | ||
456 | and t0, src, ADDRMASK | ||
457 | andi odd, dst, 0x1 /* odd buffer? */ | ||
458 | bnez t1, .Ldst_unaligned\@ | ||
459 | nop | ||
460 | bnez t0, .Lsrc_unaligned_dst_aligned\@ | ||
461 | /* | ||
462 | * use delay slot for fall-through | ||
463 | * src and dst are aligned; need to compute rem | ||
464 | */ | ||
465 | .Lboth_aligned\@: | ||
466 | SRL t0, len, LOG_NBYTES+3 # +3 for 8 units/iter | ||
467 | beqz t0, .Lcleanup_both_aligned\@ # len < 8*NBYTES | ||
468 | nop | ||
469 | SUB len, 8*NBYTES # subtract here for bgez loop | ||
470 | .align 4 | ||
471 | 1: | ||
472 | LOAD(t0, UNIT(0)(src)) | ||
473 | LOAD(t1, UNIT(1)(src)) | ||
474 | LOAD(t2, UNIT(2)(src)) | ||
475 | LOAD(t3, UNIT(3)(src)) | ||
476 | LOAD(t4, UNIT(4)(src)) | ||
477 | LOAD(t5, UNIT(5)(src)) | ||
478 | LOAD(t6, UNIT(6)(src)) | ||
479 | LOAD(t7, UNIT(7)(src)) | ||
480 | SUB len, len, 8*NBYTES | ||
481 | ADD src, src, 8*NBYTES | ||
482 | STORE(t0, UNIT(0)(dst)) | ||
483 | ADDC(t0, t1) | ||
484 | STORE(t1, UNIT(1)(dst)) | ||
485 | ADDC(sum, t0) | ||
486 | STORE(t2, UNIT(2)(dst)) | ||
487 | ADDC(t2, t3) | ||
488 | STORE(t3, UNIT(3)(dst)) | ||
489 | ADDC(sum, t2) | ||
490 | STORE(t4, UNIT(4)(dst)) | ||
491 | ADDC(t4, t5) | ||
492 | STORE(t5, UNIT(5)(dst)) | ||
493 | ADDC(sum, t4) | ||
494 | STORE(t6, UNIT(6)(dst)) | ||
495 | ADDC(t6, t7) | ||
496 | STORE(t7, UNIT(7)(dst)) | ||
497 | ADDC(sum, t6) | ||
498 | .set reorder /* DADDI_WAR */ | ||
499 | ADD dst, dst, 8*NBYTES | ||
500 | bgez len, 1b | ||
501 | .set noreorder | ||
502 | ADD len, 8*NBYTES # revert len (see above) | ||
503 | |||
504 | /* | ||
505 | * len == the number of bytes left to copy < 8*NBYTES | ||
506 | */ | ||
507 | .Lcleanup_both_aligned\@: | ||
508 | #define rem t7 | ||
509 | beqz len, .Ldone\@ | ||
510 | sltu t0, len, 4*NBYTES | ||
511 | bnez t0, .Lless_than_4units\@ | ||
512 | and rem, len, (NBYTES-1) # rem = len % NBYTES | ||
513 | /* | ||
514 | * len >= 4*NBYTES | ||
515 | */ | ||
516 | LOAD(t0, UNIT(0)(src)) | ||
517 | LOAD(t1, UNIT(1)(src)) | ||
518 | LOAD(t2, UNIT(2)(src)) | ||
519 | LOAD(t3, UNIT(3)(src)) | ||
520 | SUB len, len, 4*NBYTES | ||
521 | ADD src, src, 4*NBYTES | ||
522 | STORE(t0, UNIT(0)(dst)) | ||
523 | ADDC(t0, t1) | ||
524 | STORE(t1, UNIT(1)(dst)) | ||
525 | ADDC(sum, t0) | ||
526 | STORE(t2, UNIT(2)(dst)) | ||
527 | ADDC(t2, t3) | ||
528 | STORE(t3, UNIT(3)(dst)) | ||
529 | ADDC(sum, t2) | ||
530 | .set reorder /* DADDI_WAR */ | ||
531 | ADD dst, dst, 4*NBYTES | ||
532 | beqz len, .Ldone\@ | ||
533 | .set noreorder | ||
534 | .Lless_than_4units\@: | ||
535 | /* | ||
536 | * rem = len % NBYTES | ||
537 | */ | ||
538 | beq rem, len, .Lcopy_bytes\@ | ||
539 | nop | ||
540 | 1: | ||
541 | LOAD(t0, 0(src)) | ||
542 | ADD src, src, NBYTES | ||
543 | SUB len, len, NBYTES | ||
544 | STORE(t0, 0(dst)) | ||
545 | ADDC(sum, t0) | ||
546 | .set reorder /* DADDI_WAR */ | ||
547 | ADD dst, dst, NBYTES | ||
548 | bne rem, len, 1b | ||
549 | .set noreorder | ||
550 | |||
551 | /* | ||
552 | * src and dst are aligned, need to copy rem bytes (rem < NBYTES) | ||
553 | * A loop would do only a byte at a time with possible branch | ||
554 | * mispredicts. Can't do an explicit LOAD dst,mask,or,STORE | ||
555 | * because can't assume read-access to dst. Instead, use | ||
556 | * STREST dst, which doesn't require read access to dst. | ||
557 | * | ||
558 | * This code should perform better than a simple loop on modern, | ||
559 | * wide-issue mips processors because the code has fewer branches and | ||
560 | * more instruction-level parallelism. | ||
561 | */ | ||
562 | #define bits t2 | ||
563 | beqz len, .Ldone\@ | ||
564 | ADD t1, dst, len # t1 is just past last byte of dst | ||
565 | li bits, 8*NBYTES | ||
566 | SLL rem, len, 3 # rem = number of bits to keep | ||
567 | LOAD(t0, 0(src)) | ||
568 | SUB bits, bits, rem # bits = number of bits to discard | ||
569 | SHIFT_DISCARD t0, t0, bits | ||
570 | STREST(t0, -1(t1)) | ||
571 | SHIFT_DISCARD_REVERT t0, t0, bits | ||
572 | .set reorder | ||
573 | ADDC(sum, t0) | ||
574 | b .Ldone\@ | ||
575 | .set noreorder | ||
576 | .Ldst_unaligned\@: | ||
577 | /* | ||
578 | * dst is unaligned | ||
579 | * t0 = src & ADDRMASK | ||
580 | * t1 = dst & ADDRMASK; T1 > 0 | ||
581 | * len >= NBYTES | ||
582 | * | ||
583 | * Copy enough bytes to align dst | ||
584 | * Set match = (src and dst have same alignment) | ||
585 | */ | ||
586 | #define match rem | ||
587 | LDFIRST(t3, FIRST(0)(src)) | ||
588 | ADD t2, zero, NBYTES | ||
589 | LDREST(t3, REST(0)(src)) | ||
590 | SUB t2, t2, t1 # t2 = number of bytes copied | ||
591 | xor match, t0, t1 | ||
592 | STFIRST(t3, FIRST(0)(dst)) | ||
593 | SLL t4, t1, 3 # t4 = number of bits to discard | ||
594 | SHIFT_DISCARD t3, t3, t4 | ||
595 | /* no SHIFT_DISCARD_REVERT to handle odd buffer properly */ | ||
596 | ADDC(sum, t3) | ||
597 | beq len, t2, .Ldone\@ | ||
598 | SUB len, len, t2 | ||
599 | ADD dst, dst, t2 | ||
600 | beqz match, .Lboth_aligned\@ | ||
601 | ADD src, src, t2 | ||
602 | |||
603 | .Lsrc_unaligned_dst_aligned\@: | ||
604 | SRL t0, len, LOG_NBYTES+2 # +2 for 4 units/iter | ||
605 | beqz t0, .Lcleanup_src_unaligned\@ | ||
606 | and rem, len, (4*NBYTES-1) # rem = len % 4*NBYTES | ||
607 | 1: | ||
608 | /* | ||
609 | * Avoid consecutive LD*'s to the same register since some mips | ||
610 | * implementations can't issue them in the same cycle. | ||
611 | * It's OK to load FIRST(N+1) before REST(N) because the two addresses | ||
612 | * are to the same unit (unless src is aligned, but it's not). | ||
613 | */ | ||
614 | LDFIRST(t0, FIRST(0)(src)) | ||
615 | LDFIRST(t1, FIRST(1)(src)) | ||
616 | SUB len, len, 4*NBYTES | ||
617 | LDREST(t0, REST(0)(src)) | ||
618 | LDREST(t1, REST(1)(src)) | ||
619 | LDFIRST(t2, FIRST(2)(src)) | ||
620 | LDFIRST(t3, FIRST(3)(src)) | ||
621 | LDREST(t2, REST(2)(src)) | ||
622 | LDREST(t3, REST(3)(src)) | ||
623 | ADD src, src, 4*NBYTES | ||
624 | #ifdef CONFIG_CPU_SB1 | ||
625 | nop # improves slotting | ||
626 | #endif | ||
627 | STORE(t0, UNIT(0)(dst)) | ||
628 | ADDC(t0, t1) | ||
629 | STORE(t1, UNIT(1)(dst)) | ||
630 | ADDC(sum, t0) | ||
631 | STORE(t2, UNIT(2)(dst)) | ||
632 | ADDC(t2, t3) | ||
633 | STORE(t3, UNIT(3)(dst)) | ||
634 | ADDC(sum, t2) | ||
635 | .set reorder /* DADDI_WAR */ | ||
636 | ADD dst, dst, 4*NBYTES | ||
637 | bne len, rem, 1b | ||
638 | .set noreorder | ||
639 | |||
640 | .Lcleanup_src_unaligned\@: | ||
641 | beqz len, .Ldone\@ | ||
642 | and rem, len, NBYTES-1 # rem = len % NBYTES | ||
643 | beq rem, len, .Lcopy_bytes\@ | ||
644 | nop | ||
645 | 1: | ||
646 | LDFIRST(t0, FIRST(0)(src)) | ||
647 | LDREST(t0, REST(0)(src)) | ||
648 | ADD src, src, NBYTES | ||
649 | SUB len, len, NBYTES | ||
650 | STORE(t0, 0(dst)) | ||
651 | ADDC(sum, t0) | ||
652 | .set reorder /* DADDI_WAR */ | ||
653 | ADD dst, dst, NBYTES | ||
654 | bne len, rem, 1b | ||
655 | .set noreorder | ||
656 | |||
657 | .Lcopy_bytes_checklen\@: | ||
658 | beqz len, .Ldone\@ | ||
659 | nop | ||
660 | .Lcopy_bytes\@: | ||
661 | /* 0 < len < NBYTES */ | ||
662 | #ifdef CONFIG_CPU_LITTLE_ENDIAN | ||
663 | #define SHIFT_START 0 | ||
664 | #define SHIFT_INC 8 | ||
665 | #else | ||
666 | #define SHIFT_START 8*(NBYTES-1) | ||
667 | #define SHIFT_INC -8 | ||
668 | #endif | ||
669 | move t2, zero # partial word | ||
670 | li t3, SHIFT_START # shift | ||
671 | #define COPY_BYTE(N) \ | ||
672 | LOADBU(t0, N(src)); \ | ||
673 | SUB len, len, 1; \ | ||
674 | STOREB(t0, N(dst)); \ | ||
675 | SLLV t0, t0, t3; \ | ||
676 | addu t3, SHIFT_INC; \ | ||
677 | beqz len, .Lcopy_bytes_done\@; \ | ||
678 | or t2, t0 | ||
679 | |||
680 | COPY_BYTE(0) | ||
681 | COPY_BYTE(1) | ||
682 | #ifdef USE_DOUBLE | ||
683 | COPY_BYTE(2) | ||
684 | COPY_BYTE(3) | ||
685 | COPY_BYTE(4) | ||
686 | COPY_BYTE(5) | ||
687 | #endif | ||
688 | LOADBU(t0, NBYTES-2(src)) | ||
689 | SUB len, len, 1 | ||
690 | STOREB(t0, NBYTES-2(dst)) | ||
691 | SLLV t0, t0, t3 | ||
692 | or t2, t0 | ||
693 | .Lcopy_bytes_done\@: | ||
694 | ADDC(sum, t2) | ||
695 | .Ldone\@: | ||
696 | /* fold checksum */ | ||
697 | .set push | ||
698 | .set noat | ||
699 | #ifdef USE_DOUBLE | ||
700 | dsll32 v1, sum, 0 | ||
701 | daddu sum, v1 | ||
702 | sltu v1, sum, v1 | ||
703 | dsra32 sum, sum, 0 | ||
704 | addu sum, v1 | ||
705 | #endif | ||
706 | |||
707 | #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR5) || \ | ||
708 | defined(CONFIG_CPU_LOONGSON64) | ||
709 | .set push | ||
710 | .set arch=mips32r2 | ||
711 | wsbh v1, sum | ||
712 | movn sum, v1, odd | ||
713 | .set pop | ||
714 | #else | ||
715 | beqz odd, 1f /* odd buffer alignment? */ | ||
716 | lui v1, 0x00ff | ||
717 | addu v1, 0x00ff | ||
718 | and t0, sum, v1 | ||
719 | sll t0, t0, 8 | ||
720 | srl sum, sum, 8 | ||
721 | and sum, sum, v1 | ||
722 | or sum, sum, t0 | ||
723 | 1: | ||
724 | #endif | ||
725 | .set pop | ||
726 | .set reorder | ||
727 | jr ra | ||
728 | .set noreorder | ||
729 | .endm | ||
730 | |||
731 | .set noreorder | ||
732 | .L_exc: | ||
733 | jr ra | ||
734 | li v0, 0 | ||
735 | |||
736 | FEXPORT(__csum_partial_copy_nocheck) | ||
737 | EXPORT_SYMBOL(__csum_partial_copy_nocheck) | ||
738 | #ifndef CONFIG_EVA | ||
739 | FEXPORT(__csum_partial_copy_to_user) | ||
740 | EXPORT_SYMBOL(__csum_partial_copy_to_user) | ||
741 | FEXPORT(__csum_partial_copy_from_user) | ||
742 | EXPORT_SYMBOL(__csum_partial_copy_from_user) | ||
743 | #endif | ||
744 | __BUILD_CSUM_PARTIAL_COPY_USER LEGACY_MODE USEROP USEROP | ||
745 | |||
746 | #ifdef CONFIG_EVA | ||
747 | LEAF(__csum_partial_copy_to_user) | ||
748 | __BUILD_CSUM_PARTIAL_COPY_USER EVA_MODE KERNELOP USEROP | ||
749 | END(__csum_partial_copy_to_user) | ||
750 | |||
751 | LEAF(__csum_partial_copy_from_user) | ||
752 | __BUILD_CSUM_PARTIAL_COPY_USER EVA_MODE USEROP KERNELOP | ||
753 | END(__csum_partial_copy_from_user) | ||
754 | #endif | ||