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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / arch / mips / mm / page.c
blob36272f7d3744dc9d1a02e046f296b625a4c740cd
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 * Copyright (C) 2003, 04, 05 Ralf Baechle (ralf@linux-mips.org)
7 * Copyright (C) 2007 Maciej W. Rozycki
8 * Copyright (C) 2008 Thiemo Seufer
9 */
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/smp.h>
14 #include <linux/mm.h>
15 #include <linux/module.h>
16 #include <linux/proc_fs.h>
17
18 #include <asm/bugs.h>
19 #include <asm/cacheops.h>
20 #include <asm/inst.h>
21 #include <asm/io.h>
22 #include <asm/page.h>
23 #include <asm/pgtable.h>
24 #include <asm/prefetch.h>
25 #include <asm/system.h>
26 #include <asm/bootinfo.h>
27 #include <asm/mipsregs.h>
28 #include <asm/mmu_context.h>
29 #include <asm/cpu.h>
30 #include <asm/war.h>
31
32 #ifdef CONFIG_SIBYTE_DMA_PAGEOPS
33 #include <asm/sibyte/sb1250.h>
34 #include <asm/sibyte/sb1250_regs.h>
35 #include <asm/sibyte/sb1250_dma.h>
36 #endif
37
38 #include <asm/uasm.h>
39
40 /* Registers used in the assembled routines. */
41 #define ZERO 0
42 #define AT 2
43 #define A0 4
44 #define A1 5
45 #define A2 6
46 #define T0 8
47 #define T1 9
48 #define T2 10
49 #define T3 11
50 #define T9 25
51 #define RA 31
52
53 /* Handle labels (which must be positive integers). */
54 enum label_id {
55 label_clear_nopref = 1,
56 label_clear_pref,
57 label_copy_nopref,
58 label_copy_pref_both,
59 label_copy_pref_store,
60 };
61
62 UASM_L_LA(_clear_nopref)
63 UASM_L_LA(_clear_pref)
64 UASM_L_LA(_copy_nopref)
65 UASM_L_LA(_copy_pref_both)
66 UASM_L_LA(_copy_pref_store)
67
68 /* We need one branch and therefore one relocation per target label. */
69 static struct uasm_label __cpuinitdata labels[5];
70 static struct uasm_reloc __cpuinitdata relocs[5];
71
72 #define cpu_is_r4600_v1_x() ((read_c0_prid() & 0xfffffff0) == 0x00002010)
73 #define cpu_is_r4600_v2_x() ((read_c0_prid() & 0xfffffff0) == 0x00002020)
74
75 /*
76 * Maximum sizes:
77 *
78 * R4000 128 bytes S-cache: 0x058 bytes
79 * R4600 v1.7: 0x05c bytes
80 * R4600 v2.0: 0x060 bytes
81 * With prefetching, 16 word strides 0x120 bytes
82 */
83
84 static u32 clear_page_array[0x120 / 4];
85
86 #ifdef CONFIG_SIBYTE_DMA_PAGEOPS
87 void clear_page_cpu(void *page) __attribute__((alias("clear_page_array")));
88 #else
89 void clear_page(void *page) __attribute__((alias("clear_page_array")));
90 #endif
91
92 EXPORT_SYMBOL(clear_page);
93
94 /*
95 * Maximum sizes:
96 *
97 * R4000 128 bytes S-cache: 0x11c bytes
98 * R4600 v1.7: 0x080 bytes
99 * R4600 v2.0: 0x07c bytes
100 * With prefetching, 16 word strides 0x540 bytes
101 */
102 static u32 copy_page_array[0x540 / 4];
103
104 #ifdef CONFIG_SIBYTE_DMA_PAGEOPS
105 void
106 copy_page_cpu(void *to, void *from) __attribute__((alias("copy_page_array")));
107 #else
108 void copy_page(void *to, void *from) __attribute__((alias("copy_page_array")));
109 #endif
110
111 EXPORT_SYMBOL(copy_page);
112
113
114 static int pref_bias_clear_store __cpuinitdata;
115 static int pref_bias_copy_load __cpuinitdata;
116 static int pref_bias_copy_store __cpuinitdata;
117
118 static u32 pref_src_mode __cpuinitdata;
119 static u32 pref_dst_mode __cpuinitdata;
120
121 static int clear_word_size __cpuinitdata;
122 static int copy_word_size __cpuinitdata;
123
124 static int half_clear_loop_size __cpuinitdata;
125 static int half_copy_loop_size __cpuinitdata;
126
127 static int cache_line_size __cpuinitdata;
128 #define cache_line_mask() (cache_line_size - 1)
129
130 static inline void __cpuinit
131 pg_addiu(u32 **buf, unsigned int reg1, unsigned int reg2, unsigned int off)
132 {
133 if (cpu_has_64bit_gp_regs && DADDI_WAR && r4k_daddiu_bug()) {
134 if (off > 0x7fff) {
135 uasm_i_lui(buf, T9, uasm_rel_hi(off));
136 uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off));
137 } else
138 uasm_i_addiu(buf, T9, ZERO, off);
139 uasm_i_daddu(buf, reg1, reg2, T9);
140 } else {
141 if (off > 0x7fff) {
142 uasm_i_lui(buf, T9, uasm_rel_hi(off));
143 uasm_i_addiu(buf, T9, T9, uasm_rel_lo(off));
144 UASM_i_ADDU(buf, reg1, reg2, T9);
145 } else
146 UASM_i_ADDIU(buf, reg1, reg2, off);
147 }
148 }
149
150 static void __cpuinit set_prefetch_parameters(void)
151 {
152 if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg)
153 clear_word_size = 8;
154 else
155 clear_word_size = 4;
156
157 if (cpu_has_64bit_gp_regs)
158 copy_word_size = 8;
159 else
160 copy_word_size = 4;
161
162 /*
163 * The pref's used here are using "streaming" hints, which cause the
164 * copied data to be kicked out of the cache sooner. A page copy often
165 * ends up copying a lot more data than is commonly used, so this seems
166 * to make sense in terms of reducing cache pollution, but I've no real
167 * performance data to back this up.
168 */
169 if (cpu_has_prefetch) {
170 /*
171 * XXX: Most prefetch bias values in here are based on
172 * guesswork.
173 */
174 cache_line_size = cpu_dcache_line_size();
175 switch (current_cpu_type()) {
176 case CPU_R5500:
177 case CPU_TX49XX:
178 /* These processors only support the Pref_Load. */
179 pref_bias_copy_load = 256;
180 break;
181
182 case CPU_RM9000:
183 /*
184 * As a workaround for erratum G105 which make the
185 * PrepareForStore hint unusable we fall back to
186 * StoreRetained on the RM9000. Once it is known which
187 * versions of the RM9000 we'll be able to condition-
188 * alize this.
189 */
190
191 case CPU_R10000:
192 case CPU_R12000:
193 case CPU_R14000:
194 /*
195 * Those values have been experimentally tuned for an
196 * Origin 200.
197 */
198 pref_bias_clear_store = 512;
199 pref_bias_copy_load = 256;
200 pref_bias_copy_store = 256;
201 pref_src_mode = Pref_LoadStreamed;
202 pref_dst_mode = Pref_StoreStreamed;
203 break;
204
205 case CPU_SB1:
206 case CPU_SB1A:
207 pref_bias_clear_store = 128;
208 pref_bias_copy_load = 128;
209 pref_bias_copy_store = 128;
210 /*
211 * SB1 pass1 Pref_LoadStreamed/Pref_StoreStreamed
212 * hints are broken.
213 */
214 if (current_cpu_type() == CPU_SB1 &&
215 (current_cpu_data.processor_id & 0xff) < 0x02) {
216 pref_src_mode = Pref_Load;
217 pref_dst_mode = Pref_Store;
218 } else {
219 pref_src_mode = Pref_LoadStreamed;
220 pref_dst_mode = Pref_StoreStreamed;
221 }
222 break;
223
224 default:
225 pref_bias_clear_store = 128;
226 pref_bias_copy_load = 256;
227 pref_bias_copy_store = 128;
228 pref_src_mode = Pref_LoadStreamed;
229 pref_dst_mode = Pref_PrepareForStore;
230 break;
231 }
232 } else {
233 if (cpu_has_cache_cdex_s)
234 cache_line_size = cpu_scache_line_size();
235 else if (cpu_has_cache_cdex_p)
236 cache_line_size = cpu_dcache_line_size();
237 }
238 /*
239 * Too much unrolling will overflow the available space in
240 * clear_space_array / copy_page_array.
241 */
242 half_clear_loop_size = min(16 * clear_word_size,
243 max(cache_line_size >> 1,
244 4 * clear_word_size));
245 half_copy_loop_size = min(16 * copy_word_size,
246 max(cache_line_size >> 1,
247 4 * copy_word_size));
248 }
249
250 static void __cpuinit build_clear_store(u32 **buf, int off)
251 {
252 if (cpu_has_64bit_gp_regs || cpu_has_64bit_zero_reg) {
253 uasm_i_sd(buf, ZERO, off, A0);
254 } else {
255 uasm_i_sw(buf, ZERO, off, A0);
256 }
257 }
258
259 static inline void __cpuinit build_clear_pref(u32 **buf, int off)
260 {
261 if (off & cache_line_mask())
262 return;
263
264 if (pref_bias_clear_store) {
265 uasm_i_pref(buf, pref_dst_mode, pref_bias_clear_store + off,
266 A0);
267 } else if (cache_line_size == (half_clear_loop_size << 1)) {
268 if (cpu_has_cache_cdex_s) {
269 uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
270 } else if (cpu_has_cache_cdex_p) {
271 if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
272 uasm_i_nop(buf);
273 uasm_i_nop(buf);
274 uasm_i_nop(buf);
275 uasm_i_nop(buf);
276 }
277
278 if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
279 uasm_i_lw(buf, ZERO, ZERO, AT);
280
281 uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
282 }
283 }
284 }
285
286 void __cpuinit build_clear_page(void)
287 {
288 int off;
289 u32 *buf = (u32 *)&clear_page_array;
290 struct uasm_label *l = labels;
291 struct uasm_reloc *r = relocs;
292 int i;
293
294 memset(labels, 0, sizeof(labels));
295 memset(relocs, 0, sizeof(relocs));
296
297 set_prefetch_parameters();
298
299 /*
300 * This algorithm makes the following assumptions:
301 * - The prefetch bias is a multiple of 2 words.
302 * - The prefetch bias is less than one page.
303 */
304 BUG_ON(pref_bias_clear_store % (2 * clear_word_size));
305 BUG_ON(PAGE_SIZE < pref_bias_clear_store);
306
307 off = PAGE_SIZE - pref_bias_clear_store;
308 if (off > 0xffff || !pref_bias_clear_store)
309 pg_addiu(&buf, A2, A0, off);
310 else
311 uasm_i_ori(&buf, A2, A0, off);
312
313 if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
314 uasm_i_lui(&buf, AT, 0xa000);
315
316 off = cache_line_size ? min(8, pref_bias_clear_store / cache_line_size)
317 * cache_line_size : 0;
318 while (off) {
319 build_clear_pref(&buf, -off);
320 off -= cache_line_size;
321 }
322 uasm_l_clear_pref(&l, buf);
323 do {
324 build_clear_pref(&buf, off);
325 build_clear_store(&buf, off);
326 off += clear_word_size;
327 } while (off < half_clear_loop_size);
328 pg_addiu(&buf, A0, A0, 2 * off);
329 off = -off;
330 do {
331 build_clear_pref(&buf, off);
332 if (off == -clear_word_size)
333 uasm_il_bne(&buf, &r, A0, A2, label_clear_pref);
334 build_clear_store(&buf, off);
335 off += clear_word_size;
336 } while (off < 0);
337
338 if (pref_bias_clear_store) {
339 pg_addiu(&buf, A2, A0, pref_bias_clear_store);
340 uasm_l_clear_nopref(&l, buf);
341 off = 0;
342 do {
343 build_clear_store(&buf, off);
344 off += clear_word_size;
345 } while (off < half_clear_loop_size);
346 pg_addiu(&buf, A0, A0, 2 * off);
347 off = -off;
348 do {
349 if (off == -clear_word_size)
350 uasm_il_bne(&buf, &r, A0, A2,
351 label_clear_nopref);
352 build_clear_store(&buf, off);
353 off += clear_word_size;
354 } while (off < 0);
355 }
356
357 uasm_i_jr(&buf, RA);
358 uasm_i_nop(&buf);
359
360 BUG_ON(buf > clear_page_array + ARRAY_SIZE(clear_page_array));
361
362 uasm_resolve_relocs(relocs, labels);
363
364 pr_debug("Synthesized clear page handler (%u instructions).\n",
365 (u32)(buf - clear_page_array));
366
367 pr_debug("\t.set push\n");
368 pr_debug("\t.set noreorder\n");
369 for (i = 0; i < (buf - clear_page_array); i++)
370 pr_debug("\t.word 0x%08x\n", clear_page_array[i]);
371 pr_debug("\t.set pop\n");
372 }
373
374 static void __cpuinit build_copy_load(u32 **buf, int reg, int off)
375 {
376 if (cpu_has_64bit_gp_regs) {
377 uasm_i_ld(buf, reg, off, A1);
378 } else {
379 uasm_i_lw(buf, reg, off, A1);
380 }
381 }
382
383 static void __cpuinit build_copy_store(u32 **buf, int reg, int off)
384 {
385 if (cpu_has_64bit_gp_regs) {
386 uasm_i_sd(buf, reg, off, A0);
387 } else {
388 uasm_i_sw(buf, reg, off, A0);
389 }
390 }
391
392 static inline void build_copy_load_pref(u32 **buf, int off)
393 {
394 if (off & cache_line_mask())
395 return;
396
397 if (pref_bias_copy_load)
398 uasm_i_pref(buf, pref_src_mode, pref_bias_copy_load + off, A1);
399 }
400
401 static inline void build_copy_store_pref(u32 **buf, int off)
402 {
403 if (off & cache_line_mask())
404 return;
405
406 if (pref_bias_copy_store) {
407 uasm_i_pref(buf, pref_dst_mode, pref_bias_copy_store + off,
408 A0);
409 } else if (cache_line_size == (half_copy_loop_size << 1)) {
410 if (cpu_has_cache_cdex_s) {
411 uasm_i_cache(buf, Create_Dirty_Excl_SD, off, A0);
412 } else if (cpu_has_cache_cdex_p) {
413 if (R4600_V1_HIT_CACHEOP_WAR && cpu_is_r4600_v1_x()) {
414 uasm_i_nop(buf);
415 uasm_i_nop(buf);
416 uasm_i_nop(buf);
417 uasm_i_nop(buf);
418 }
419
420 if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
421 uasm_i_lw(buf, ZERO, ZERO, AT);
422
423 uasm_i_cache(buf, Create_Dirty_Excl_D, off, A0);
424 }
425 }
426 }
427
428 void __cpuinit build_copy_page(void)
429 {
430 int off;
431 u32 *buf = (u32 *)&copy_page_array;
432 struct uasm_label *l = labels;
433 struct uasm_reloc *r = relocs;
434 int i;
435
436 memset(labels, 0, sizeof(labels));
437 memset(relocs, 0, sizeof(relocs));
438
439 set_prefetch_parameters();
440
441 /*
442 * This algorithm makes the following assumptions:
443 * - All prefetch biases are multiples of 8 words.
444 * - The prefetch biases are less than one page.
445 * - The store prefetch bias isn't greater than the load
446 * prefetch bias.
447 */
448 BUG_ON(pref_bias_copy_load % (8 * copy_word_size));
449 BUG_ON(pref_bias_copy_store % (8 * copy_word_size));
450 BUG_ON(PAGE_SIZE < pref_bias_copy_load);
451 BUG_ON(pref_bias_copy_store > pref_bias_copy_load);
452
453 off = PAGE_SIZE - pref_bias_copy_load;
454 if (off > 0xffff || !pref_bias_copy_load)
455 pg_addiu(&buf, A2, A0, off);
456 else
457 uasm_i_ori(&buf, A2, A0, off);
458
459 if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())
460 uasm_i_lui(&buf, AT, 0xa000);
461
462 off = cache_line_size ? min(8, pref_bias_copy_load / cache_line_size) *
463 cache_line_size : 0;
464 while (off) {
465 build_copy_load_pref(&buf, -off);
466 off -= cache_line_size;
467 }
468 off = cache_line_size ? min(8, pref_bias_copy_store / cache_line_size) *
469 cache_line_size : 0;
470 while (off) {
471 build_copy_store_pref(&buf, -off);
472 off -= cache_line_size;
473 }
474 uasm_l_copy_pref_both(&l, buf);
475 do {
476 build_copy_load_pref(&buf, off);
477 build_copy_load(&buf, T0, off);
478 build_copy_load_pref(&buf, off + copy_word_size);
479 build_copy_load(&buf, T1, off + copy_word_size);
480 build_copy_load_pref(&buf, off + 2 * copy_word_size);
481 build_copy_load(&buf, T2, off + 2 * copy_word_size);
482 build_copy_load_pref(&buf, off + 3 * copy_word_size);
483 build_copy_load(&buf, T3, off + 3 * copy_word_size);
484 build_copy_store_pref(&buf, off);
485 build_copy_store(&buf, T0, off);
486 build_copy_store_pref(&buf, off + copy_word_size);
487 build_copy_store(&buf, T1, off + copy_word_size);
488 build_copy_store_pref(&buf, off + 2 * copy_word_size);
489 build_copy_store(&buf, T2, off + 2 * copy_word_size);
490 build_copy_store_pref(&buf, off + 3 * copy_word_size);
491 build_copy_store(&buf, T3, off + 3 * copy_word_size);
492 off += 4 * copy_word_size;
493 } while (off < half_copy_loop_size);
494 pg_addiu(&buf, A1, A1, 2 * off);
495 pg_addiu(&buf, A0, A0, 2 * off);
496 off = -off;
497 do {
498 build_copy_load_pref(&buf, off);
499 build_copy_load(&buf, T0, off);
500 build_copy_load_pref(&buf, off + copy_word_size);
501 build_copy_load(&buf, T1, off + copy_word_size);
502 build_copy_load_pref(&buf, off + 2 * copy_word_size);
503 build_copy_load(&buf, T2, off + 2 * copy_word_size);
504 build_copy_load_pref(&buf, off + 3 * copy_word_size);
505 build_copy_load(&buf, T3, off + 3 * copy_word_size);
506 build_copy_store_pref(&buf, off);
507 build_copy_store(&buf, T0, off);
508 build_copy_store_pref(&buf, off + copy_word_size);
509 build_copy_store(&buf, T1, off + copy_word_size);
510 build_copy_store_pref(&buf, off + 2 * copy_word_size);
511 build_copy_store(&buf, T2, off + 2 * copy_word_size);
512 build_copy_store_pref(&buf, off + 3 * copy_word_size);
513 if (off == -(4 * copy_word_size))
514 uasm_il_bne(&buf, &r, A2, A0, label_copy_pref_both);
515 build_copy_store(&buf, T3, off + 3 * copy_word_size);
516 off += 4 * copy_word_size;
517 } while (off < 0);
518
519 if (pref_bias_copy_load - pref_bias_copy_store) {
520 pg_addiu(&buf, A2, A0,
521 pref_bias_copy_load - pref_bias_copy_store);
522 uasm_l_copy_pref_store(&l, buf);
523 off = 0;
524 do {
525 build_copy_load(&buf, T0, off);
526 build_copy_load(&buf, T1, off + copy_word_size);
527 build_copy_load(&buf, T2, off + 2 * copy_word_size);
528 build_copy_load(&buf, T3, off + 3 * copy_word_size);
529 build_copy_store_pref(&buf, off);
530 build_copy_store(&buf, T0, off);
531 build_copy_store_pref(&buf, off + copy_word_size);
532 build_copy_store(&buf, T1, off + copy_word_size);
533 build_copy_store_pref(&buf, off + 2 * copy_word_size);
534 build_copy_store(&buf, T2, off + 2 * copy_word_size);
535 build_copy_store_pref(&buf, off + 3 * copy_word_size);
536 build_copy_store(&buf, T3, off + 3 * copy_word_size);
537 off += 4 * copy_word_size;
538 } while (off < half_copy_loop_size);
539 pg_addiu(&buf, A1, A1, 2 * off);
540 pg_addiu(&buf, A0, A0, 2 * off);
541 off = -off;
542 do {
543 build_copy_load(&buf, T0, off);
544 build_copy_load(&buf, T1, off + copy_word_size);
545 build_copy_load(&buf, T2, off + 2 * copy_word_size);
546 build_copy_load(&buf, T3, off + 3 * copy_word_size);
547 build_copy_store_pref(&buf, off);
548 build_copy_store(&buf, T0, off);
549 build_copy_store_pref(&buf, off + copy_word_size);
550 build_copy_store(&buf, T1, off + copy_word_size);
551 build_copy_store_pref(&buf, off + 2 * copy_word_size);
552 build_copy_store(&buf, T2, off + 2 * copy_word_size);
553 build_copy_store_pref(&buf, off + 3 * copy_word_size);
554 if (off == -(4 * copy_word_size))
555 uasm_il_bne(&buf, &r, A2, A0,
556 label_copy_pref_store);
557 build_copy_store(&buf, T3, off + 3 * copy_word_size);
558 off += 4 * copy_word_size;
559 } while (off < 0);
560 }
561
562 if (pref_bias_copy_store) {
563 pg_addiu(&buf, A2, A0, pref_bias_copy_store);
564 uasm_l_copy_nopref(&l, buf);
565 off = 0;
566 do {
567 build_copy_load(&buf, T0, off);
568 build_copy_load(&buf, T1, off + copy_word_size);
569 build_copy_load(&buf, T2, off + 2 * copy_word_size);
570 build_copy_load(&buf, T3, off + 3 * copy_word_size);
571 build_copy_store(&buf, T0, off);
572 build_copy_store(&buf, T1, off + copy_word_size);
573 build_copy_store(&buf, T2, off + 2 * copy_word_size);
574 build_copy_store(&buf, T3, off + 3 * copy_word_size);
575 off += 4 * copy_word_size;
576 } while (off < half_copy_loop_size);
577 pg_addiu(&buf, A1, A1, 2 * off);
578 pg_addiu(&buf, A0, A0, 2 * off);
579 off = -off;
580 do {
581 build_copy_load(&buf, T0, off);
582 build_copy_load(&buf, T1, off + copy_word_size);
583 build_copy_load(&buf, T2, off + 2 * copy_word_size);
584 build_copy_load(&buf, T3, off + 3 * copy_word_size);
585 build_copy_store(&buf, T0, off);
586 build_copy_store(&buf, T1, off + copy_word_size);
587 build_copy_store(&buf, T2, off + 2 * copy_word_size);
588 if (off == -(4 * copy_word_size))
589 uasm_il_bne(&buf, &r, A2, A0,
590 label_copy_nopref);
591 build_copy_store(&buf, T3, off + 3 * copy_word_size);
592 off += 4 * copy_word_size;
593 } while (off < 0);
594 }
595
596 uasm_i_jr(&buf, RA);
597 uasm_i_nop(&buf);
598
599 BUG_ON(buf > copy_page_array + ARRAY_SIZE(copy_page_array));
600
601 uasm_resolve_relocs(relocs, labels);
602
603 pr_debug("Synthesized copy page handler (%u instructions).\n",
604 (u32)(buf - copy_page_array));
605
606 pr_debug("\t.set push\n");
607 pr_debug("\t.set noreorder\n");
608 for (i = 0; i < (buf - copy_page_array); i++)
609 pr_debug("\t.word 0x%08x\n", copy_page_array[i]);
610 pr_debug("\t.set pop\n");
611 }
612
613 #ifdef CONFIG_SIBYTE_DMA_PAGEOPS
614
615 /*
616 * Pad descriptors to cacheline, since each is exclusively owned by a
617 * particular CPU.
618 */
619 struct dmadscr {
620 u64 dscr_a;
621 u64 dscr_b;
622 u64 pad_a;
623 u64 pad_b;
624 } ____cacheline_aligned_in_smp page_descr[DM_NUM_CHANNELS];
625
626 void sb1_dma_init(void)
627 {
628 int i;
629
630 for (i = 0; i < DM_NUM_CHANNELS; i++) {
631 const u64 base_val = CPHYSADDR((unsigned long)&page_descr[i]) |
632 V_DM_DSCR_BASE_RINGSZ(1);
633 void *base_reg = IOADDR(A_DM_REGISTER(i, R_DM_DSCR_BASE));
634
635 __raw_writeq(base_val, base_reg);
636 __raw_writeq(base_val | M_DM_DSCR_BASE_RESET, base_reg);
637 __raw_writeq(base_val | M_DM_DSCR_BASE_ENABL, base_reg);
638 }
639 }
640
641 void clear_page(void *page)
642 {
643 u64 to_phys = CPHYSADDR((unsigned long)page);
644 unsigned int cpu = smp_processor_id();
645
646 /* if the page is not in KSEG0, use old way */
647 if ((long)KSEGX((unsigned long)page) != (long)CKSEG0)
648 return clear_page_cpu(page);
649
650 page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_ZERO_MEM |
651 M_DM_DSCRA_L2C_DEST | M_DM_DSCRA_INTERRUPT;
652 page_descr[cpu].dscr_b = V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
653 __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
654
655 /*
656 * Don't really want to do it this way, but there's no
657 * reliable way to delay completion detection.
658 */
659 while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
660 & M_DM_DSCR_BASE_INTERRUPT))
661 ;
662 __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
663 }
664
665 void copy_page(void *to, void *from)
666 {
667 u64 from_phys = CPHYSADDR((unsigned long)from);
668 u64 to_phys = CPHYSADDR((unsigned long)to);
669 unsigned int cpu = smp_processor_id();
670
671 /* if any page is not in KSEG0, use old way */
672 if ((long)KSEGX((unsigned long)to) != (long)CKSEG0
673 || (long)KSEGX((unsigned long)from) != (long)CKSEG0)
674 return copy_page_cpu(to, from);
675
676 page_descr[cpu].dscr_a = to_phys | M_DM_DSCRA_L2C_DEST |
677 M_DM_DSCRA_INTERRUPT;
678 page_descr[cpu].dscr_b = from_phys | V_DM_DSCRB_SRC_LENGTH(PAGE_SIZE);
679 __raw_writeq(1, IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_COUNT)));
680
681 /*
682 * Don't really want to do it this way, but there's no
683 * reliable way to delay completion detection.
684 */
685 while (!(__raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE_DEBUG)))
686 & M_DM_DSCR_BASE_INTERRUPT))
687 ;
688 __raw_readq(IOADDR(A_DM_REGISTER(cpu, R_DM_DSCR_BASE)));
689 }
690
691 #endif /* CONFIG_SIBYTE_DMA_PAGEOPS */
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