xref: /linux/arch/mips/mm/c-r4k.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
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) 1996 David S. Miller (dm@engr.sgi.com)
7  * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  */
10 #include <linux/config.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/mm.h>
15 #include <linux/bitops.h>
16 
17 #include <asm/bcache.h>
18 #include <asm/bootinfo.h>
19 #include <asm/cache.h>
20 #include <asm/cacheops.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 #include <asm/io.h>
24 #include <asm/page.h>
25 #include <asm/pgtable.h>
26 #include <asm/r4kcache.h>
27 #include <asm/system.h>
28 #include <asm/mmu_context.h>
29 #include <asm/war.h>
30 #include <asm/cacheflush.h> /* for run_uncached() */
31 
32 /*
33  * Must die.
34  */
35 static unsigned long icache_size __read_mostly;
36 static unsigned long dcache_size __read_mostly;
37 static unsigned long scache_size __read_mostly;
38 
39 /*
40  * Dummy cache handling routines for machines without boardcaches
41  */
42 static void no_sc_noop(void) {}
43 
44 static struct bcache_ops no_sc_ops = {
45 	.bc_enable = (void *)no_sc_noop,
46 	.bc_disable = (void *)no_sc_noop,
47 	.bc_wback_inv = (void *)no_sc_noop,
48 	.bc_inv = (void *)no_sc_noop
49 };
50 
51 struct bcache_ops *bcops = &no_sc_ops;
52 
53 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
54 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
55 
56 #define R4600_HIT_CACHEOP_WAR_IMPL					\
57 do {									\
58 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
59 		*(volatile unsigned long *)CKSEG1;			\
60 	if (R4600_V1_HIT_CACHEOP_WAR)					\
61 		__asm__ __volatile__("nop;nop;nop;nop");		\
62 } while (0)
63 
64 static void (*r4k_blast_dcache_page)(unsigned long addr);
65 
66 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
67 {
68 	R4600_HIT_CACHEOP_WAR_IMPL;
69 	blast_dcache32_page(addr);
70 }
71 
72 static inline void r4k_blast_dcache_page_setup(void)
73 {
74 	unsigned long  dc_lsize = cpu_dcache_line_size();
75 
76 	if (dc_lsize == 16)
77 		r4k_blast_dcache_page = blast_dcache16_page;
78 	else if (dc_lsize == 32)
79 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
80 }
81 
82 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
83 
84 static inline void r4k_blast_dcache_page_indexed_setup(void)
85 {
86 	unsigned long dc_lsize = cpu_dcache_line_size();
87 
88 	if (dc_lsize == 16)
89 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
90 	else if (dc_lsize == 32)
91 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
92 }
93 
94 static void (* r4k_blast_dcache)(void);
95 
96 static inline void r4k_blast_dcache_setup(void)
97 {
98 	unsigned long dc_lsize = cpu_dcache_line_size();
99 
100 	if (dc_lsize == 16)
101 		r4k_blast_dcache = blast_dcache16;
102 	else if (dc_lsize == 32)
103 		r4k_blast_dcache = blast_dcache32;
104 }
105 
106 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
107 #define JUMP_TO_ALIGN(order) \
108 	__asm__ __volatile__( \
109 		"b\t1f\n\t" \
110 		".align\t" #order "\n\t" \
111 		"1:\n\t" \
112 		)
113 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
114 #define CACHE32_UNROLL32_ALIGN2	JUMP_TO_ALIGN(11)
115 
116 static inline void blast_r4600_v1_icache32(void)
117 {
118 	unsigned long flags;
119 
120 	local_irq_save(flags);
121 	blast_icache32();
122 	local_irq_restore(flags);
123 }
124 
125 static inline void tx49_blast_icache32(void)
126 {
127 	unsigned long start = INDEX_BASE;
128 	unsigned long end = start + current_cpu_data.icache.waysize;
129 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
130 	unsigned long ws_end = current_cpu_data.icache.ways <<
131 	                       current_cpu_data.icache.waybit;
132 	unsigned long ws, addr;
133 
134 	CACHE32_UNROLL32_ALIGN2;
135 	/* I'm in even chunk.  blast odd chunks */
136 	for (ws = 0; ws < ws_end; ws += ws_inc)
137 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
138 			cache32_unroll32(addr|ws,Index_Invalidate_I);
139 	CACHE32_UNROLL32_ALIGN;
140 	/* I'm in odd chunk.  blast even chunks */
141 	for (ws = 0; ws < ws_end; ws += ws_inc)
142 		for (addr = start; addr < end; addr += 0x400 * 2)
143 			cache32_unroll32(addr|ws,Index_Invalidate_I);
144 }
145 
146 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
147 {
148 	unsigned long flags;
149 
150 	local_irq_save(flags);
151 	blast_icache32_page_indexed(page);
152 	local_irq_restore(flags);
153 }
154 
155 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
156 {
157 	unsigned long start = page;
158 	unsigned long end = start + PAGE_SIZE;
159 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
160 	unsigned long ws_end = current_cpu_data.icache.ways <<
161 	                       current_cpu_data.icache.waybit;
162 	unsigned long ws, addr;
163 
164 	CACHE32_UNROLL32_ALIGN2;
165 	/* I'm in even chunk.  blast odd chunks */
166 	for (ws = 0; ws < ws_end; ws += ws_inc)
167 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
168 			cache32_unroll32(addr|ws,Index_Invalidate_I);
169 	CACHE32_UNROLL32_ALIGN;
170 	/* I'm in odd chunk.  blast even chunks */
171 	for (ws = 0; ws < ws_end; ws += ws_inc)
172 		for (addr = start; addr < end; addr += 0x400 * 2)
173 			cache32_unroll32(addr|ws,Index_Invalidate_I);
174 }
175 
176 static void (* r4k_blast_icache_page)(unsigned long addr);
177 
178 static inline void r4k_blast_icache_page_setup(void)
179 {
180 	unsigned long ic_lsize = cpu_icache_line_size();
181 
182 	if (ic_lsize == 16)
183 		r4k_blast_icache_page = blast_icache16_page;
184 	else if (ic_lsize == 32)
185 		r4k_blast_icache_page = blast_icache32_page;
186 	else if (ic_lsize == 64)
187 		r4k_blast_icache_page = blast_icache64_page;
188 }
189 
190 
191 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
192 
193 static inline void r4k_blast_icache_page_indexed_setup(void)
194 {
195 	unsigned long ic_lsize = cpu_icache_line_size();
196 
197 	if (ic_lsize == 16)
198 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
199 	else if (ic_lsize == 32) {
200 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
201 			r4k_blast_icache_page_indexed =
202 				blast_icache32_r4600_v1_page_indexed;
203 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
204 			r4k_blast_icache_page_indexed =
205 				tx49_blast_icache32_page_indexed;
206 		else
207 			r4k_blast_icache_page_indexed =
208 				blast_icache32_page_indexed;
209 	} else if (ic_lsize == 64)
210 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
211 }
212 
213 static void (* r4k_blast_icache)(void);
214 
215 static inline void r4k_blast_icache_setup(void)
216 {
217 	unsigned long ic_lsize = cpu_icache_line_size();
218 
219 	if (ic_lsize == 16)
220 		r4k_blast_icache = blast_icache16;
221 	else if (ic_lsize == 32) {
222 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
223 			r4k_blast_icache = blast_r4600_v1_icache32;
224 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
225 			r4k_blast_icache = tx49_blast_icache32;
226 		else
227 			r4k_blast_icache = blast_icache32;
228 	} else if (ic_lsize == 64)
229 		r4k_blast_icache = blast_icache64;
230 }
231 
232 static void (* r4k_blast_scache_page)(unsigned long addr);
233 
234 static inline void r4k_blast_scache_page_setup(void)
235 {
236 	unsigned long sc_lsize = cpu_scache_line_size();
237 
238 	if (scache_size == 0)
239 		r4k_blast_scache_page = (void *)no_sc_noop;
240 	else if (sc_lsize == 16)
241 		r4k_blast_scache_page = blast_scache16_page;
242 	else if (sc_lsize == 32)
243 		r4k_blast_scache_page = blast_scache32_page;
244 	else if (sc_lsize == 64)
245 		r4k_blast_scache_page = blast_scache64_page;
246 	else if (sc_lsize == 128)
247 		r4k_blast_scache_page = blast_scache128_page;
248 }
249 
250 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
251 
252 static inline void r4k_blast_scache_page_indexed_setup(void)
253 {
254 	unsigned long sc_lsize = cpu_scache_line_size();
255 
256 	if (scache_size == 0)
257 		r4k_blast_scache_page_indexed = (void *)no_sc_noop;
258 	else if (sc_lsize == 16)
259 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
260 	else if (sc_lsize == 32)
261 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
262 	else if (sc_lsize == 64)
263 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
264 	else if (sc_lsize == 128)
265 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
266 }
267 
268 static void (* r4k_blast_scache)(void);
269 
270 static inline void r4k_blast_scache_setup(void)
271 {
272 	unsigned long sc_lsize = cpu_scache_line_size();
273 
274 	if (scache_size == 0)
275 		r4k_blast_scache = (void *)no_sc_noop;
276 	else if (sc_lsize == 16)
277 		r4k_blast_scache = blast_scache16;
278 	else if (sc_lsize == 32)
279 		r4k_blast_scache = blast_scache32;
280 	else if (sc_lsize == 64)
281 		r4k_blast_scache = blast_scache64;
282 	else if (sc_lsize == 128)
283 		r4k_blast_scache = blast_scache128;
284 }
285 
286 /*
287  * This is former mm's flush_cache_all() which really should be
288  * flush_cache_vunmap these days ...
289  */
290 static inline void local_r4k_flush_cache_all(void * args)
291 {
292 	r4k_blast_dcache();
293 	r4k_blast_icache();
294 }
295 
296 static void r4k_flush_cache_all(void)
297 {
298 	if (!cpu_has_dc_aliases)
299 		return;
300 
301 	on_each_cpu(local_r4k_flush_cache_all, NULL, 1, 1);
302 }
303 
304 static inline void local_r4k___flush_cache_all(void * args)
305 {
306 	r4k_blast_dcache();
307 	r4k_blast_icache();
308 
309 	switch (current_cpu_data.cputype) {
310 	case CPU_R4000SC:
311 	case CPU_R4000MC:
312 	case CPU_R4400SC:
313 	case CPU_R4400MC:
314 	case CPU_R10000:
315 	case CPU_R12000:
316 		r4k_blast_scache();
317 	}
318 }
319 
320 static void r4k___flush_cache_all(void)
321 {
322 	on_each_cpu(local_r4k___flush_cache_all, NULL, 1, 1);
323 }
324 
325 static inline void local_r4k_flush_cache_range(void * args)
326 {
327 	struct vm_area_struct *vma = args;
328 	int exec;
329 
330 	if (!(cpu_context(smp_processor_id(), vma->vm_mm)))
331 		return;
332 
333 	exec = vma->vm_flags & VM_EXEC;
334 	if (cpu_has_dc_aliases || exec)
335 		r4k_blast_dcache();
336 	if (exec)
337 		r4k_blast_icache();
338 }
339 
340 static void r4k_flush_cache_range(struct vm_area_struct *vma,
341 	unsigned long start, unsigned long end)
342 {
343 	on_each_cpu(local_r4k_flush_cache_range, vma, 1, 1);
344 }
345 
346 static inline void local_r4k_flush_cache_mm(void * args)
347 {
348 	struct mm_struct *mm = args;
349 
350 	if (!cpu_context(smp_processor_id(), mm))
351 		return;
352 
353 	r4k_blast_dcache();
354 	r4k_blast_icache();
355 
356 	/*
357 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
358 	 * only flush the primary caches but R10000 and R12000 behave sane ...
359 	 */
360 	if (current_cpu_data.cputype == CPU_R4000SC ||
361 	    current_cpu_data.cputype == CPU_R4000MC ||
362 	    current_cpu_data.cputype == CPU_R4400SC ||
363 	    current_cpu_data.cputype == CPU_R4400MC)
364 		r4k_blast_scache();
365 }
366 
367 static void r4k_flush_cache_mm(struct mm_struct *mm)
368 {
369 	if (!cpu_has_dc_aliases)
370 		return;
371 
372 	on_each_cpu(local_r4k_flush_cache_mm, mm, 1, 1);
373 }
374 
375 struct flush_cache_page_args {
376 	struct vm_area_struct *vma;
377 	unsigned long addr;
378 	unsigned long pfn;
379 };
380 
381 static inline void local_r4k_flush_cache_page(void *args)
382 {
383 	struct flush_cache_page_args *fcp_args = args;
384 	struct vm_area_struct *vma = fcp_args->vma;
385 	unsigned long addr = fcp_args->addr;
386 	unsigned long paddr = fcp_args->pfn << PAGE_SHIFT;
387 	int exec = vma->vm_flags & VM_EXEC;
388 	struct mm_struct *mm = vma->vm_mm;
389 	pgd_t *pgdp;
390 	pud_t *pudp;
391 	pmd_t *pmdp;
392 	pte_t *ptep;
393 
394 	/*
395 	 * If ownes no valid ASID yet, cannot possibly have gotten
396 	 * this page into the cache.
397 	 */
398 	if (cpu_context(smp_processor_id(), mm) == 0)
399 		return;
400 
401 	addr &= PAGE_MASK;
402 	pgdp = pgd_offset(mm, addr);
403 	pudp = pud_offset(pgdp, addr);
404 	pmdp = pmd_offset(pudp, addr);
405 	ptep = pte_offset(pmdp, addr);
406 
407 	/*
408 	 * If the page isn't marked valid, the page cannot possibly be
409 	 * in the cache.
410 	 */
411 	if (!(pte_val(*ptep) & _PAGE_PRESENT))
412 		return;
413 
414 	/*
415 	 * Doing flushes for another ASID than the current one is
416 	 * too difficult since stupid R4k caches do a TLB translation
417 	 * for every cache flush operation.  So we do indexed flushes
418 	 * in that case, which doesn't overly flush the cache too much.
419 	 */
420 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID)) {
421 		if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
422 			r4k_blast_dcache_page(addr);
423 			if (exec && !cpu_icache_snoops_remote_store)
424 				r4k_blast_scache_page(addr);
425 		}
426 		if (exec)
427 			r4k_blast_icache_page(addr);
428 
429 		return;
430 	}
431 
432 	/*
433 	 * Do indexed flush, too much work to get the (possible) TLB refills
434 	 * to work correctly.
435 	 */
436 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
437 		r4k_blast_dcache_page_indexed(cpu_has_pindexed_dcache ?
438 					      paddr : addr);
439 		if (exec && !cpu_icache_snoops_remote_store) {
440 			r4k_blast_scache_page_indexed(paddr);
441 		}
442 	}
443 	if (exec) {
444 		if (cpu_has_vtag_icache) {
445 			int cpu = smp_processor_id();
446 
447 			if (cpu_context(cpu, mm) != 0)
448 				drop_mmu_context(mm, cpu);
449 		} else
450 			r4k_blast_icache_page_indexed(addr);
451 	}
452 }
453 
454 static void r4k_flush_cache_page(struct vm_area_struct *vma,
455 	unsigned long addr, unsigned long pfn)
456 {
457 	struct flush_cache_page_args args;
458 
459 	args.vma = vma;
460 	args.addr = addr;
461 	args.pfn = pfn;
462 
463 	on_each_cpu(local_r4k_flush_cache_page, &args, 1, 1);
464 }
465 
466 static inline void local_r4k_flush_data_cache_page(void * addr)
467 {
468 	r4k_blast_dcache_page((unsigned long) addr);
469 }
470 
471 static void r4k_flush_data_cache_page(unsigned long addr)
472 {
473 	on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr, 1, 1);
474 }
475 
476 struct flush_icache_range_args {
477 	unsigned long start;
478 	unsigned long end;
479 };
480 
481 static inline void local_r4k_flush_icache_range(void *args)
482 {
483 	struct flush_icache_range_args *fir_args = args;
484 	unsigned long start = fir_args->start;
485 	unsigned long end = fir_args->end;
486 
487 	if (!cpu_has_ic_fills_f_dc) {
488 		if (end - start > dcache_size) {
489 			r4k_blast_dcache();
490 		} else {
491 			R4600_HIT_CACHEOP_WAR_IMPL;
492 			protected_blast_dcache_range(start, end);
493 		}
494 
495 		if (!cpu_icache_snoops_remote_store && scache_size) {
496 			if (end - start > scache_size)
497 				r4k_blast_scache();
498 			else
499 				protected_blast_scache_range(start, end);
500 		}
501 	}
502 
503 	if (end - start > icache_size)
504 		r4k_blast_icache();
505 	else
506 		protected_blast_icache_range(start, end);
507 }
508 
509 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
510 {
511 	struct flush_icache_range_args args;
512 
513 	args.start = start;
514 	args.end = end;
515 
516 	on_each_cpu(local_r4k_flush_icache_range, &args, 1, 1);
517 	instruction_hazard();
518 }
519 
520 /*
521  * Ok, this seriously sucks.  We use them to flush a user page but don't
522  * know the virtual address, so we have to blast away the whole icache
523  * which is significantly more expensive than the real thing.  Otoh we at
524  * least know the kernel address of the page so we can flush it
525  * selectivly.
526  */
527 
528 struct flush_icache_page_args {
529 	struct vm_area_struct *vma;
530 	struct page *page;
531 };
532 
533 static inline void local_r4k_flush_icache_page(void *args)
534 {
535 	struct flush_icache_page_args *fip_args = args;
536 	struct vm_area_struct *vma = fip_args->vma;
537 	struct page *page = fip_args->page;
538 
539 	/*
540 	 * Tricky ...  Because we don't know the virtual address we've got the
541 	 * choice of either invalidating the entire primary and secondary
542 	 * caches or invalidating the secondary caches also.  With the subset
543 	 * enforcment on R4000SC, R4400SC, R10000 and R12000 invalidating the
544 	 * secondary cache will result in any entries in the primary caches
545 	 * also getting invalidated which hopefully is a bit more economical.
546 	 */
547 	if (cpu_has_subset_pcaches) {
548 		unsigned long addr = (unsigned long) page_address(page);
549 
550 		r4k_blast_scache_page(addr);
551 		ClearPageDcacheDirty(page);
552 
553 		return;
554 	}
555 
556 	if (!cpu_has_ic_fills_f_dc) {
557 		unsigned long addr = (unsigned long) page_address(page);
558 		r4k_blast_dcache_page(addr);
559 		if (!cpu_icache_snoops_remote_store)
560 			r4k_blast_scache_page(addr);
561 		ClearPageDcacheDirty(page);
562 	}
563 
564 	/*
565 	 * We're not sure of the virtual address(es) involved here, so
566 	 * we have to flush the entire I-cache.
567 	 */
568 	if (cpu_has_vtag_icache) {
569 		int cpu = smp_processor_id();
570 
571 		if (cpu_context(cpu, vma->vm_mm) != 0)
572 			drop_mmu_context(vma->vm_mm, cpu);
573 	} else
574 		r4k_blast_icache();
575 }
576 
577 static void r4k_flush_icache_page(struct vm_area_struct *vma,
578 	struct page *page)
579 {
580 	struct flush_icache_page_args args;
581 
582 	/*
583 	 * If there's no context yet, or the page isn't executable, no I-cache
584 	 * flush is needed.
585 	 */
586 	if (!(vma->vm_flags & VM_EXEC))
587 		return;
588 
589 	args.vma = vma;
590 	args.page = page;
591 
592 	on_each_cpu(local_r4k_flush_icache_page, &args, 1, 1);
593 }
594 
595 
596 #ifdef CONFIG_DMA_NONCOHERENT
597 
598 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
599 {
600 	/* Catch bad driver code */
601 	BUG_ON(size == 0);
602 
603 	if (cpu_has_subset_pcaches) {
604 		if (size >= scache_size)
605 			r4k_blast_scache();
606 		else
607 			blast_scache_range(addr, addr + size);
608 		return;
609 	}
610 
611 	/*
612 	 * Either no secondary cache or the available caches don't have the
613 	 * subset property so we have to flush the primary caches
614 	 * explicitly
615 	 */
616 	if (size >= dcache_size) {
617 		r4k_blast_dcache();
618 	} else {
619 		R4600_HIT_CACHEOP_WAR_IMPL;
620 		blast_dcache_range(addr, addr + size);
621 	}
622 
623 	bc_wback_inv(addr, size);
624 }
625 
626 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
627 {
628 	/* Catch bad driver code */
629 	BUG_ON(size == 0);
630 
631 	if (cpu_has_subset_pcaches) {
632 		if (size >= scache_size)
633 			r4k_blast_scache();
634 		else
635 			blast_scache_range(addr, addr + size);
636 		return;
637 	}
638 
639 	if (size >= dcache_size) {
640 		r4k_blast_dcache();
641 	} else {
642 		R4600_HIT_CACHEOP_WAR_IMPL;
643 		blast_dcache_range(addr, addr + size);
644 	}
645 
646 	bc_inv(addr, size);
647 }
648 #endif /* CONFIG_DMA_NONCOHERENT */
649 
650 /*
651  * While we're protected against bad userland addresses we don't care
652  * very much about what happens in that case.  Usually a segmentation
653  * fault will dump the process later on anyway ...
654  */
655 static void local_r4k_flush_cache_sigtramp(void * arg)
656 {
657 	unsigned long ic_lsize = cpu_icache_line_size();
658 	unsigned long dc_lsize = cpu_dcache_line_size();
659 	unsigned long sc_lsize = cpu_scache_line_size();
660 	unsigned long addr = (unsigned long) arg;
661 
662 	R4600_HIT_CACHEOP_WAR_IMPL;
663 	protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
664 	if (!cpu_icache_snoops_remote_store && scache_size)
665 		protected_writeback_scache_line(addr & ~(sc_lsize - 1));
666 	protected_flush_icache_line(addr & ~(ic_lsize - 1));
667 	if (MIPS4K_ICACHE_REFILL_WAR) {
668 		__asm__ __volatile__ (
669 			".set push\n\t"
670 			".set noat\n\t"
671 			".set mips3\n\t"
672 #ifdef CONFIG_32BIT
673 			"la	$at,1f\n\t"
674 #endif
675 #ifdef CONFIG_64BIT
676 			"dla	$at,1f\n\t"
677 #endif
678 			"cache	%0,($at)\n\t"
679 			"nop; nop; nop\n"
680 			"1:\n\t"
681 			".set pop"
682 			:
683 			: "i" (Hit_Invalidate_I));
684 	}
685 	if (MIPS_CACHE_SYNC_WAR)
686 		__asm__ __volatile__ ("sync");
687 }
688 
689 static void r4k_flush_cache_sigtramp(unsigned long addr)
690 {
691 	on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr, 1, 1);
692 }
693 
694 static void r4k_flush_icache_all(void)
695 {
696 	if (cpu_has_vtag_icache)
697 		r4k_blast_icache();
698 }
699 
700 static inline void rm7k_erratum31(void)
701 {
702 	const unsigned long ic_lsize = 32;
703 	unsigned long addr;
704 
705 	/* RM7000 erratum #31. The icache is screwed at startup. */
706 	write_c0_taglo(0);
707 	write_c0_taghi(0);
708 
709 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
710 		__asm__ __volatile__ (
711 			".set push\n\t"
712 			".set noreorder\n\t"
713 			".set mips3\n\t"
714 			"cache\t%1, 0(%0)\n\t"
715 			"cache\t%1, 0x1000(%0)\n\t"
716 			"cache\t%1, 0x2000(%0)\n\t"
717 			"cache\t%1, 0x3000(%0)\n\t"
718 			"cache\t%2, 0(%0)\n\t"
719 			"cache\t%2, 0x1000(%0)\n\t"
720 			"cache\t%2, 0x2000(%0)\n\t"
721 			"cache\t%2, 0x3000(%0)\n\t"
722 			"cache\t%1, 0(%0)\n\t"
723 			"cache\t%1, 0x1000(%0)\n\t"
724 			"cache\t%1, 0x2000(%0)\n\t"
725 			"cache\t%1, 0x3000(%0)\n\t"
726 			".set pop\n"
727 			:
728 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
729 	}
730 }
731 
732 static char *way_string[] __initdata = { NULL, "direct mapped", "2-way",
733 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
734 };
735 
736 static void __init probe_pcache(void)
737 {
738 	struct cpuinfo_mips *c = &current_cpu_data;
739 	unsigned int config = read_c0_config();
740 	unsigned int prid = read_c0_prid();
741 	unsigned long config1;
742 	unsigned int lsize;
743 
744 	switch (c->cputype) {
745 	case CPU_R4600:			/* QED style two way caches? */
746 	case CPU_R4700:
747 	case CPU_R5000:
748 	case CPU_NEVADA:
749 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
750 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
751 		c->icache.ways = 2;
752 		c->icache.waybit = ffs(icache_size/2) - 1;
753 
754 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
755 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
756 		c->dcache.ways = 2;
757 		c->dcache.waybit= ffs(dcache_size/2) - 1;
758 
759 		c->options |= MIPS_CPU_CACHE_CDEX_P;
760 		break;
761 
762 	case CPU_R5432:
763 	case CPU_R5500:
764 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
765 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
766 		c->icache.ways = 2;
767 		c->icache.waybit= 0;
768 
769 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
770 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
771 		c->dcache.ways = 2;
772 		c->dcache.waybit = 0;
773 
774 		c->options |= MIPS_CPU_CACHE_CDEX_P;
775 		break;
776 
777 	case CPU_TX49XX:
778 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
779 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
780 		c->icache.ways = 4;
781 		c->icache.waybit= 0;
782 
783 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
784 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
785 		c->dcache.ways = 4;
786 		c->dcache.waybit = 0;
787 
788 		c->options |= MIPS_CPU_CACHE_CDEX_P;
789 		c->options |= MIPS_CPU_PREFETCH;
790 		break;
791 
792 	case CPU_R4000PC:
793 	case CPU_R4000SC:
794 	case CPU_R4000MC:
795 	case CPU_R4400PC:
796 	case CPU_R4400SC:
797 	case CPU_R4400MC:
798 	case CPU_R4300:
799 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
800 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
801 		c->icache.ways = 1;
802 		c->icache.waybit = 0; 	/* doesn't matter */
803 
804 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
805 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
806 		c->dcache.ways = 1;
807 		c->dcache.waybit = 0;	/* does not matter */
808 
809 		c->options |= MIPS_CPU_CACHE_CDEX_P;
810 		break;
811 
812 	case CPU_R10000:
813 	case CPU_R12000:
814 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
815 		c->icache.linesz = 64;
816 		c->icache.ways = 2;
817 		c->icache.waybit = 0;
818 
819 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
820 		c->dcache.linesz = 32;
821 		c->dcache.ways = 2;
822 		c->dcache.waybit = 0;
823 
824 		c->options |= MIPS_CPU_PREFETCH;
825 		break;
826 
827 	case CPU_VR4133:
828 		write_c0_config(config & ~CONF_EB);
829 	case CPU_VR4131:
830 		/* Workaround for cache instruction bug of VR4131 */
831 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
832 		    c->processor_id == 0x0c82U) {
833 			config &= ~0x00000030U;
834 			config |= 0x00410000U;
835 			write_c0_config(config);
836 		}
837 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
838 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
839 		c->icache.ways = 2;
840 		c->icache.waybit = ffs(icache_size/2) - 1;
841 
842 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
843 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
844 		c->dcache.ways = 2;
845 		c->dcache.waybit = ffs(dcache_size/2) - 1;
846 
847 		c->options |= MIPS_CPU_CACHE_CDEX_P;
848 		break;
849 
850 	case CPU_VR41XX:
851 	case CPU_VR4111:
852 	case CPU_VR4121:
853 	case CPU_VR4122:
854 	case CPU_VR4181:
855 	case CPU_VR4181A:
856 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
857 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
858 		c->icache.ways = 1;
859 		c->icache.waybit = 0; 	/* doesn't matter */
860 
861 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
862 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
863 		c->dcache.ways = 1;
864 		c->dcache.waybit = 0;	/* does not matter */
865 
866 		c->options |= MIPS_CPU_CACHE_CDEX_P;
867 		break;
868 
869 	case CPU_RM7000:
870 		rm7k_erratum31();
871 
872 	case CPU_RM9000:
873 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
874 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
875 		c->icache.ways = 4;
876 		c->icache.waybit = ffs(icache_size / c->icache.ways) - 1;
877 
878 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
879 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
880 		c->dcache.ways = 4;
881 		c->dcache.waybit = ffs(dcache_size / c->dcache.ways) - 1;
882 
883 #if !defined(CONFIG_SMP) || !defined(RM9000_CDEX_SMP_WAR)
884 		c->options |= MIPS_CPU_CACHE_CDEX_P;
885 #endif
886 		c->options |= MIPS_CPU_PREFETCH;
887 		break;
888 
889 	default:
890 		if (!(config & MIPS_CONF_M))
891 			panic("Don't know how to probe P-caches on this cpu.");
892 
893 		/*
894 		 * So we seem to be a MIPS32 or MIPS64 CPU
895 		 * So let's probe the I-cache ...
896 		 */
897 		config1 = read_c0_config1();
898 
899 		if ((lsize = ((config1 >> 19) & 7)))
900 			c->icache.linesz = 2 << lsize;
901 		else
902 			c->icache.linesz = lsize;
903 		c->icache.sets = 64 << ((config1 >> 22) & 7);
904 		c->icache.ways = 1 + ((config1 >> 16) & 7);
905 
906 		icache_size = c->icache.sets *
907 		              c->icache.ways *
908 		              c->icache.linesz;
909 		c->icache.waybit = ffs(icache_size/c->icache.ways) - 1;
910 
911 		if (config & 0x8)		/* VI bit */
912 			c->icache.flags |= MIPS_CACHE_VTAG;
913 
914 		/*
915 		 * Now probe the MIPS32 / MIPS64 data cache.
916 		 */
917 		c->dcache.flags = 0;
918 
919 		if ((lsize = ((config1 >> 10) & 7)))
920 			c->dcache.linesz = 2 << lsize;
921 		else
922 			c->dcache.linesz= lsize;
923 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
924 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
925 
926 		dcache_size = c->dcache.sets *
927 		              c->dcache.ways *
928 		              c->dcache.linesz;
929 		c->dcache.waybit = ffs(dcache_size/c->dcache.ways) - 1;
930 
931 		c->options |= MIPS_CPU_PREFETCH;
932 		break;
933 	}
934 
935 	/*
936 	 * Processor configuration sanity check for the R4000SC erratum
937 	 * #5.  With page sizes larger than 32kB there is no possibility
938 	 * to get a VCE exception anymore so we don't care about this
939 	 * misconfiguration.  The case is rather theoretical anyway;
940 	 * presumably no vendor is shipping his hardware in the "bad"
941 	 * configuration.
942 	 */
943 	if ((prid & 0xff00) == PRID_IMP_R4000 && (prid & 0xff) < 0x40 &&
944 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
945 	    PAGE_SIZE <= 0x8000)
946 		panic("Improper R4000SC processor configuration detected");
947 
948 	/* compute a couple of other cache variables */
949 	c->icache.waysize = icache_size / c->icache.ways;
950 	c->dcache.waysize = dcache_size / c->dcache.ways;
951 
952 	c->icache.sets = icache_size / (c->icache.linesz * c->icache.ways);
953 	c->dcache.sets = dcache_size / (c->dcache.linesz * c->dcache.ways);
954 
955 	/*
956 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
957 	 * 2-way virtually indexed so normally would suffer from aliases.  So
958 	 * normally they'd suffer from aliases but magic in the hardware deals
959 	 * with that for us so we don't need to take care ourselves.
960 	 */
961 	switch (c->cputype) {
962 	case CPU_20KC:
963 	case CPU_25KF:
964 		c->dcache.flags |= MIPS_CACHE_PINDEX;
965 	case CPU_R10000:
966 	case CPU_R12000:
967 	case CPU_SB1:
968 		break;
969 	case CPU_24K:
970 		if (!(read_c0_config7() & (1 << 16)))
971 	default:
972 			if (c->dcache.waysize > PAGE_SIZE)
973 				c->dcache.flags |= MIPS_CACHE_ALIASES;
974 	}
975 
976 	switch (c->cputype) {
977 	case CPU_20KC:
978 		/*
979 		 * Some older 20Kc chips doesn't have the 'VI' bit in
980 		 * the config register.
981 		 */
982 		c->icache.flags |= MIPS_CACHE_VTAG;
983 		break;
984 
985 	case CPU_AU1000:
986 	case CPU_AU1500:
987 	case CPU_AU1100:
988 	case CPU_AU1550:
989 	case CPU_AU1200:
990 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
991 		break;
992 	}
993 
994 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
995 	       icache_size >> 10,
996 	       cpu_has_vtag_icache ? "virtually tagged" : "physically tagged",
997 	       way_string[c->icache.ways], c->icache.linesz);
998 
999 	printk("Primary data cache %ldkB, %s, linesize %d bytes.\n",
1000 	       dcache_size >> 10, way_string[c->dcache.ways], c->dcache.linesz);
1001 }
1002 
1003 /*
1004  * If you even _breathe_ on this function, look at the gcc output and make sure
1005  * it does not pop things on and off the stack for the cache sizing loop that
1006  * executes in KSEG1 space or else you will crash and burn badly.  You have
1007  * been warned.
1008  */
1009 static int __init probe_scache(void)
1010 {
1011 	extern unsigned long stext;
1012 	unsigned long flags, addr, begin, end, pow2;
1013 	unsigned int config = read_c0_config();
1014 	struct cpuinfo_mips *c = &current_cpu_data;
1015 	int tmp;
1016 
1017 	if (config & CONF_SC)
1018 		return 0;
1019 
1020 	begin = (unsigned long) &stext;
1021 	begin &= ~((4 * 1024 * 1024) - 1);
1022 	end = begin + (4 * 1024 * 1024);
1023 
1024 	/*
1025 	 * This is such a bitch, you'd think they would make it easy to do
1026 	 * this.  Away you daemons of stupidity!
1027 	 */
1028 	local_irq_save(flags);
1029 
1030 	/* Fill each size-multiple cache line with a valid tag. */
1031 	pow2 = (64 * 1024);
1032 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1033 		unsigned long *p = (unsigned long *) addr;
1034 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1035 		pow2 <<= 1;
1036 	}
1037 
1038 	/* Load first line with zero (therefore invalid) tag. */
1039 	write_c0_taglo(0);
1040 	write_c0_taghi(0);
1041 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1042 	cache_op(Index_Store_Tag_I, begin);
1043 	cache_op(Index_Store_Tag_D, begin);
1044 	cache_op(Index_Store_Tag_SD, begin);
1045 
1046 	/* Now search for the wrap around point. */
1047 	pow2 = (128 * 1024);
1048 	tmp = 0;
1049 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1050 		cache_op(Index_Load_Tag_SD, addr);
1051 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1052 		if (!read_c0_taglo())
1053 			break;
1054 		pow2 <<= 1;
1055 	}
1056 	local_irq_restore(flags);
1057 	addr -= begin;
1058 
1059 	scache_size = addr;
1060 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1061 	c->scache.ways = 1;
1062 	c->dcache.waybit = 0;		/* does not matter */
1063 
1064 	return 1;
1065 }
1066 
1067 extern int r5k_sc_init(void);
1068 extern int rm7k_sc_init(void);
1069 
1070 static void __init setup_scache(void)
1071 {
1072 	struct cpuinfo_mips *c = &current_cpu_data;
1073 	unsigned int config = read_c0_config();
1074 	int sc_present = 0;
1075 
1076 	/*
1077 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1078 	 * processors don't have a S-cache that would be relevant to the
1079 	 * Linux memory managment.
1080 	 */
1081 	switch (c->cputype) {
1082 	case CPU_R4000SC:
1083 	case CPU_R4000MC:
1084 	case CPU_R4400SC:
1085 	case CPU_R4400MC:
1086 		sc_present = run_uncached(probe_scache);
1087 		if (sc_present)
1088 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1089 		break;
1090 
1091 	case CPU_R10000:
1092 	case CPU_R12000:
1093 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1094 		c->scache.linesz = 64 << ((config >> 13) & 1);
1095 		c->scache.ways = 2;
1096 		c->scache.waybit= 0;
1097 		sc_present = 1;
1098 		break;
1099 
1100 	case CPU_R5000:
1101 	case CPU_NEVADA:
1102 #ifdef CONFIG_R5000_CPU_SCACHE
1103 		r5k_sc_init();
1104 #endif
1105                 return;
1106 
1107 	case CPU_RM7000:
1108 	case CPU_RM9000:
1109 #ifdef CONFIG_RM7000_CPU_SCACHE
1110 		rm7k_sc_init();
1111 #endif
1112 		return;
1113 
1114 	default:
1115 		sc_present = 0;
1116 	}
1117 
1118 	if (!sc_present)
1119 		return;
1120 
1121 	if ((c->isa_level == MIPS_CPU_ISA_M32R1 ||
1122 	     c->isa_level == MIPS_CPU_ISA_M64R1) &&
1123 	    !(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1124 		panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1125 
1126 	/* compute a couple of other cache variables */
1127 	c->scache.waysize = scache_size / c->scache.ways;
1128 
1129 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1130 
1131 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1132 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1133 
1134 	c->options |= MIPS_CPU_SUBSET_CACHES;
1135 }
1136 
1137 static inline void coherency_setup(void)
1138 {
1139 	change_c0_config(CONF_CM_CMASK, CONF_CM_DEFAULT);
1140 
1141 	/*
1142 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1143 	 * the coherency mode specified by the TLB; 1 means cachable
1144 	 * coherent update on write will be used.  Not all processors have
1145 	 * this bit and; some wire it to zero, others like Toshiba had the
1146 	 * silly idea of putting something else there ...
1147 	 */
1148 	switch (current_cpu_data.cputype) {
1149 	case CPU_R4000PC:
1150 	case CPU_R4000SC:
1151 	case CPU_R4000MC:
1152 	case CPU_R4400PC:
1153 	case CPU_R4400SC:
1154 	case CPU_R4400MC:
1155 		clear_c0_config(CONF_CU);
1156 		break;
1157 	}
1158 }
1159 
1160 void __init r4k_cache_init(void)
1161 {
1162 	extern void build_clear_page(void);
1163 	extern void build_copy_page(void);
1164 	extern char except_vec2_generic;
1165 	struct cpuinfo_mips *c = &current_cpu_data;
1166 
1167 	/* Default cache error handler for R4000 and R5000 family */
1168 	set_uncached_handler (0x100, &except_vec2_generic, 0x80);
1169 
1170 	probe_pcache();
1171 	setup_scache();
1172 
1173 	r4k_blast_dcache_page_setup();
1174 	r4k_blast_dcache_page_indexed_setup();
1175 	r4k_blast_dcache_setup();
1176 	r4k_blast_icache_page_setup();
1177 	r4k_blast_icache_page_indexed_setup();
1178 	r4k_blast_icache_setup();
1179 	r4k_blast_scache_page_setup();
1180 	r4k_blast_scache_page_indexed_setup();
1181 	r4k_blast_scache_setup();
1182 
1183 	/*
1184 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1185 	 * This code supports virtually indexed processors and will be
1186 	 * unnecessarily inefficient on physically indexed processors.
1187 	 */
1188 	shm_align_mask = max_t( unsigned long,
1189 				c->dcache.sets * c->dcache.linesz - 1,
1190 				PAGE_SIZE - 1);
1191 
1192 	flush_cache_all		= r4k_flush_cache_all;
1193 	__flush_cache_all	= r4k___flush_cache_all;
1194 	flush_cache_mm		= r4k_flush_cache_mm;
1195 	flush_cache_page	= r4k_flush_cache_page;
1196 	flush_icache_page	= r4k_flush_icache_page;
1197 	flush_cache_range	= r4k_flush_cache_range;
1198 
1199 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1200 	flush_icache_all	= r4k_flush_icache_all;
1201 	flush_data_cache_page	= r4k_flush_data_cache_page;
1202 	flush_icache_range	= r4k_flush_icache_range;
1203 
1204 #ifdef CONFIG_DMA_NONCOHERENT
1205 	_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1206 	_dma_cache_wback	= r4k_dma_cache_wback_inv;
1207 	_dma_cache_inv		= r4k_dma_cache_inv;
1208 #endif
1209 
1210 	build_clear_page();
1211 	build_copy_page();
1212 	local_r4k___flush_cache_all(NULL);
1213 	coherency_setup();
1214 }
1215