1 /* SPDX-License-Identifier: GPL-2.0-or-later *
2 /*
3 * Memory copy functions for 32-bit PowerPC.
4 *
5 * Copyright (C) 1996-2005 Paul Mackerras.
6 */
7 #include <linux/export.h>
8 #include <asm/processor.h>
9 #include <asm/cache.h>
10 #include <asm/errno.h>
11 #include <asm/ppc_asm.h>
12 #include <asm/code-patching-asm.h>
13 #include <asm/kasan.h>
14
15 #define COPY_16_BYTES \
16 lwz r7,4(r4); \
17 lwz r8,8(r4); \
18 lwz r9,12(r4); \
19 lwzu r10,16(r4); \
20 stw r7,4(r6); \
21 stw r8,8(r6); \
22 stw r9,12(r6); \
23 stwu r10,16(r6)
24
25 #define COPY_16_BYTES_WITHEX(n) \
26 8 ## n ## 0: \
27 lwz r7,4(r4); \
28 8 ## n ## 1: \
29 lwz r8,8(r4); \
30 8 ## n ## 2: \
31 lwz r9,12(r4); \
32 8 ## n ## 3: \
33 lwzu r10,16(r4); \
34 8 ## n ## 4: \
35 stw r7,4(r6); \
36 8 ## n ## 5: \
37 stw r8,8(r6); \
38 8 ## n ## 6: \
39 stw r9,12(r6); \
40 8 ## n ## 7: \
41 stwu r10,16(r6)
42
43 #define COPY_16_BYTES_EXCODE(n)
44 9 ## n ## 0:
45 addi r5,r5,-(16 * n);
46 b 104f;
47 9 ## n ## 1:
48 addi r5,r5,-(16 * n);
49 b 105f;
50 EX_TABLE(8 ## n ## 0b,9 ## n ## 0b);
51 EX_TABLE(8 ## n ## 1b,9 ## n ## 0b);
52 EX_TABLE(8 ## n ## 2b,9 ## n ## 0b);
53 EX_TABLE(8 ## n ## 3b,9 ## n ## 0b);
54 EX_TABLE(8 ## n ## 4b,9 ## n ## 1b);
55 EX_TABLE(8 ## n ## 5b,9 ## n ## 1b);
56 EX_TABLE(8 ## n ## 6b,9 ## n ## 1b);
57 EX_TABLE(8 ## n ## 7b,9 ## n ## 1b)
58
59 .text
60
61 CACHELINE_BYTES = L1_CACHE_BYTES
62 LG_CACHELINE_BYTES = L1_CACHE_SHIFT
63 CACHELINE_MASK = (L1_CACHE_BYTES-1)
64
65 #ifndef CONFIG_KASAN
66 _GLOBAL(memset16)
67 rlwinm. r0 ,r5, 31, 1, 31
68 addi r6, r3, -4
69 beq- 2f
70 rlwimi r4 ,r4 ,16 ,0 ,15
71 mtctr r0
72 1: stwu r4, 4(r6)
73 bdnz 1b
74 2: andi. r0, r5, 1
75 beqlr
76 sth r4, 4(r6)
77 blr
78 EXPORT_SYMBOL(memset16)
79 #endif
80
81 /*
82 * Use dcbz on the complete cache lines in the
83 * to set them to zero. This requires that th
84 * area is cacheable. -- paulus
85 *
86 * During early init, cache might not be activ
87 * We therefore skip the optimised bloc that u
88 * replaced by a nop once cache is active. Thi
89 */
90 _GLOBAL_KASAN(memset)
91 cmplwi 0,r5,4
92 blt 7f
93
94 rlwimi r4,r4,8,16,23
95 rlwimi r4,r4,16,0,15
96
97 stw r4,0(r3)
98 beqlr
99 andi. r0,r3,3
100 add r5,r0,r5
101 subf r6,r0,r3
102 cmplwi 0,r4,0
103 /*
104 * Skip optimised bloc until cache is
105 * by 'bne' during boot to use normal
106 */
107 5: b 2f
108 patch_site 5b, patch__memset_noca
109
110 clrlwi r7,r6,32-LG_CACHELINE_BYTES
111 add r8,r7,r5
112 srwi r9,r8,LG_CACHELINE_BYTES
113 addic. r9,r9,-1 /* total numbe
114 ble 2f
115 xori r0,r7,CACHELINE_MASK & ~3
116 srwi. r0,r0,2
117 beq 3f
118 mtctr r0
119 4: stwu r4,4(r6)
120 bdnz 4b
121 3: mtctr r9
122 li r7,4
123 10: dcbz r7,r6
124 addi r6,r6,CACHELINE_BYTES
125 bdnz 10b
126 clrlwi r5,r8,32-LG_CACHELINE_BYTES
127 addi r5,r5,4
128
129 2: srwi r0,r5,2
130 mtctr r0
131 bdz 6f
132 1: stwu r4,4(r6)
133 bdnz 1b
134 6: andi. r5,r5,3
135 beqlr
136 mtctr r5
137 addi r6,r6,3
138 8: stbu r4,1(r6)
139 bdnz 8b
140 blr
141
142 7: cmpwi 0,r5,0
143 beqlr
144 mtctr r5
145 addi r6,r3,-1
146 9: stbu r4,1(r6)
147 bdnz 9b
148 blr
149 EXPORT_SYMBOL(memset)
150 EXPORT_SYMBOL_KASAN(memset)
151
152 /*
153 * This version uses dcbz on the complete cach
154 * destination area to reduce memory traffic.
155 * the destination area is cacheable.
156 * We only use this version if the source and
157 * -- paulus.
158 *
159 * During early init, cache might not be activ
160 * We therefore jump to generic_memcpy which d
161 * replaced by a nop once cache is active. Thi
162 */
163 _GLOBAL_KASAN(memmove)
164 cmplw 0,r3,r4
165 bgt backwards_memcpy
166 /* fall through */
167
168 _GLOBAL_KASAN(memcpy)
169 1: b generic_memcpy
170 patch_site 1b, patch__memcpy_noca
171
172 add r7,r3,r5 /* tes
173 add r8,r4,r5
174 cmplw 0,r4,r7
175 cmplw 1,r3,r8
176 crand 0,0,4 /* cr0
177 blt generic_memcpy /* if
178
179 addi r4,r4,-4
180 addi r6,r3,-4
181 neg r0,r3
182 andi. r0,r0,CACHELINE_MASK /* # b
183 beq 58f
184
185 cmplw 0,r5,r0 /* is
186 blt 63f /* if
187 andi. r8,r0,3 /* get
188 subf r5,r0,r5
189 mtctr r8
190 beq+ 61f
191 70: lbz r9,4(r4) /* do
192 addi r4,r4,1
193 addi r6,r6,1
194 stb r9,3(r6)
195 bdnz 70b
196 61: srwi. r0,r0,2
197 mtctr r0
198 beq 58f
199 72: lwzu r9,4(r4) /* do
200 stwu r9,4(r6)
201 bdnz 72b
202
203 58: srwi. r0,r5,LG_CACHELINE_BYTES /* #
204 clrlwi r5,r5,32-LG_CACHELINE_BYTES
205 li r11,4
206 mtctr r0
207 beq 63f
208 53:
209 dcbz r11,r6
210 COPY_16_BYTES
211 #if L1_CACHE_BYTES >= 32
212 COPY_16_BYTES
213 #if L1_CACHE_BYTES >= 64
214 COPY_16_BYTES
215 COPY_16_BYTES
216 #if L1_CACHE_BYTES >= 128
217 COPY_16_BYTES
218 COPY_16_BYTES
219 COPY_16_BYTES
220 COPY_16_BYTES
221 #endif
222 #endif
223 #endif
224 bdnz 53b
225
226 63: srwi. r0,r5,2
227 mtctr r0
228 beq 64f
229 30: lwzu r0,4(r4)
230 stwu r0,4(r6)
231 bdnz 30b
232
233 64: andi. r0,r5,3
234 mtctr r0
235 beq+ 65f
236 addi r4,r4,3
237 addi r6,r6,3
238 40: lbzu r0,1(r4)
239 stbu r0,1(r6)
240 bdnz 40b
241 65: blr
242 EXPORT_SYMBOL(memcpy)
243 EXPORT_SYMBOL(memmove)
244 EXPORT_SYMBOL_KASAN(memcpy)
245 EXPORT_SYMBOL_KASAN(memmove)
246
247 generic_memcpy:
248 srwi. r7,r5,3
249 addi r6,r3,-4
250 addi r4,r4,-4
251 beq 2f /* if
252 andi. r0,r6,3 /* get
253 mtctr r7
254 bne 5f
255 1: lwz r7,4(r4)
256 lwzu r8,8(r4)
257 stw r7,4(r6)
258 stwu r8,8(r6)
259 bdnz 1b
260 andi. r5,r5,7
261 2: cmplwi 0,r5,4
262 blt 3f
263 lwzu r0,4(r4)
264 addi r5,r5,-4
265 stwu r0,4(r6)
266 3: cmpwi 0,r5,0
267 beqlr
268 mtctr r5
269 addi r4,r4,3
270 addi r6,r6,3
271 4: lbzu r0,1(r4)
272 stbu r0,1(r6)
273 bdnz 4b
274 blr
275 5: subfic r0,r0,4
276 mtctr r0
277 6: lbz r7,4(r4)
278 addi r4,r4,1
279 stb r7,4(r6)
280 addi r6,r6,1
281 bdnz 6b
282 subf r5,r0,r5
283 rlwinm. r7,r5,32-3,3,31
284 beq 2b
285 mtctr r7
286 b 1b
287
288 _GLOBAL(backwards_memcpy)
289 rlwinm. r7,r5,32-3,3,31 /* r0
290 add r6,r3,r5
291 add r4,r4,r5
292 beq 2f
293 andi. r0,r6,3
294 mtctr r7
295 bne 5f
296 1: lwz r7,-4(r4)
297 lwzu r8,-8(r4)
298 stw r7,-4(r6)
299 stwu r8,-8(r6)
300 bdnz 1b
301 andi. r5,r5,7
302 2: cmplwi 0,r5,4
303 blt 3f
304 lwzu r0,-4(r4)
305 subi r5,r5,4
306 stwu r0,-4(r6)
307 3: cmpwi 0,r5,0
308 beqlr
309 mtctr r5
310 4: lbzu r0,-1(r4)
311 stbu r0,-1(r6)
312 bdnz 4b
313 blr
314 5: mtctr r0
315 6: lbzu r7,-1(r4)
316 stbu r7,-1(r6)
317 bdnz 6b
318 subf r5,r0,r5
319 rlwinm. r7,r5,32-3,3,31
320 beq 2b
321 mtctr r7
322 b 1b
323
324 _GLOBAL(__copy_tofrom_user)
325 addi r4,r4,-4
326 addi r6,r3,-4
327 neg r0,r3
328 andi. r0,r0,CACHELINE_MASK /* # b
329 beq 58f
330
331 cmplw 0,r5,r0 /* is
332 blt 63f /* if
333 andi. r8,r0,3 /* get
334 mtctr r8
335 beq+ 61f
336 70: lbz r9,4(r4) /* do
337 71: stb r9,4(r6)
338 addi r4,r4,1
339 addi r6,r6,1
340 bdnz 70b
341 61: subf r5,r0,r5
342 srwi. r0,r0,2
343 mtctr r0
344 beq 58f
345 72: lwzu r9,4(r4) /* do
346 73: stwu r9,4(r6)
347 bdnz 72b
348
349 EX_TABLE(70b,100f)
350 EX_TABLE(71b,101f)
351 EX_TABLE(72b,102f)
352 EX_TABLE(73b,103f)
353
354 58: srwi. r0,r5,LG_CACHELINE_BYTES /* #
355 clrlwi r5,r5,32-LG_CACHELINE_BYTES
356 li r11,4
357 beq 63f
358
359 /* Here we decide how far ahead to pre
360 li r3,4
361 cmpwi r0,1
362 li r7,0
363 ble 114f
364 li r7,1
365 #if MAX_COPY_PREFETCH > 1
366 /* Heuristically, for large transfers
367 MAX_COPY_PREFETCH cachelines ahead.
368 we prefetch 1 cacheline ahead. */
369 cmpwi r0,MAX_COPY_PREFETCH
370 ble 112f
371 li r7,MAX_COPY_PREFETCH
372 112: mtctr r7
373 111: dcbt r3,r4
374 addi r3,r3,CACHELINE_BYTES
375 bdnz 111b
376 #else
377 dcbt r3,r4
378 addi r3,r3,CACHELINE_BYTES
379 #endif /* MAX_COPY_PREFETCH > 1 */
380
381 114: subf r8,r7,r0
382 mr r0,r7
383 mtctr r8
384
385 53: dcbt r3,r4
386 54: dcbz r11,r6
387 EX_TABLE(54b,105f)
388 /* the main body of the cacheline loop */
389 COPY_16_BYTES_WITHEX(0)
390 #if L1_CACHE_BYTES >= 32
391 COPY_16_BYTES_WITHEX(1)
392 #if L1_CACHE_BYTES >= 64
393 COPY_16_BYTES_WITHEX(2)
394 COPY_16_BYTES_WITHEX(3)
395 #if L1_CACHE_BYTES >= 128
396 COPY_16_BYTES_WITHEX(4)
397 COPY_16_BYTES_WITHEX(5)
398 COPY_16_BYTES_WITHEX(6)
399 COPY_16_BYTES_WITHEX(7)
400 #endif
401 #endif
402 #endif
403 bdnz 53b
404 cmpwi r0,0
405 li r3,4
406 li r7,0
407 bne 114b
408
409 63: srwi. r0,r5,2
410 mtctr r0
411 beq 64f
412 30: lwzu r0,4(r4)
413 31: stwu r0,4(r6)
414 bdnz 30b
415
416 64: andi. r0,r5,3
417 mtctr r0
418 beq+ 65f
419 40: lbz r0,4(r4)
420 41: stb r0,4(r6)
421 addi r4,r4,1
422 addi r6,r6,1
423 bdnz 40b
424 65: li r3,0
425 blr
426
427 /* read fault, initial single-byte copy */
428 100: li r9,0
429 b 90f
430 /* write fault, initial single-byte copy */
431 101: li r9,1
432 90: subf r5,r8,r5
433 li r3,0
434 b 99f
435 /* read fault, initial word copy */
436 102: li r9,0
437 b 91f
438 /* write fault, initial word copy */
439 103: li r9,1
440 91: li r3,2
441 b 99f
442
443 /*
444 * this stuff handles faults in the cacheline
445 * 104f (if in read part) or 105f (if in write
446 */
447 COPY_16_BYTES_EXCODE(0)
448 #if L1_CACHE_BYTES >= 32
449 COPY_16_BYTES_EXCODE(1)
450 #if L1_CACHE_BYTES >= 64
451 COPY_16_BYTES_EXCODE(2)
452 COPY_16_BYTES_EXCODE(3)
453 #if L1_CACHE_BYTES >= 128
454 COPY_16_BYTES_EXCODE(4)
455 COPY_16_BYTES_EXCODE(5)
456 COPY_16_BYTES_EXCODE(6)
457 COPY_16_BYTES_EXCODE(7)
458 #endif
459 #endif
460 #endif
461
462 /* read fault in cacheline loop */
463 104: li r9,0
464 b 92f
465 /* fault on dcbz (effectively a write fault) *
466 /* or write fault in cacheline loop */
467 105: li r9,1
468 92: li r3,LG_CACHELINE_BYTES
469 mfctr r8
470 add r0,r0,r8
471 b 106f
472 /* read fault in final word loop */
473 108: li r9,0
474 b 93f
475 /* write fault in final word loop */
476 109: li r9,1
477 93: andi. r5,r5,3
478 li r3,2
479 b 99f
480 /* read fault in final byte loop */
481 110: li r9,0
482 b 94f
483 /* write fault in final byte loop */
484 111: li r9,1
485 94: li r5,0
486 li r3,0
487 /*
488 * At this stage the number of bytes not copie
489 * r5 + (ctr << r3), and r9 is 0 for read or 1
490 */
491 99: mfctr r0
492 106: slw r3,r0,r3
493 add. r3,r3,r5
494 beq 120f /* sho
495 cmpwi 0,r9,0
496 bne 120f
497 /* for a read fault, first try to continue the
498 mtctr r3
499 130: lbz r0,4(r4)
500 131: stb r0,4(r6)
501 addi r4,r4,1
502 addi r6,r6,1
503 bdnz 130b
504 /* then clear out the destination: r3 bytes st
505 132: mfctr r3
506 120: blr
507
508 EX_TABLE(30b,108b)
509 EX_TABLE(31b,109b)
510 EX_TABLE(40b,110b)
511 EX_TABLE(41b,111b)
512 EX_TABLE(130b,132b)
513 EX_TABLE(131b,120b)
514
515 EXPORT_SYMBOL(__copy_tofrom_user)
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