xref: /openbmc/linux/arch/mips/mm/c-r4k.c (revision 36bccb11)
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 (davem@davemloft.net)
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/hardirq.h>
11 #include <linux/init.h>
12 #include <linux/highmem.h>
13 #include <linux/kernel.h>
14 #include <linux/linkage.h>
15 #include <linux/preempt.h>
16 #include <linux/sched.h>
17 #include <linux/smp.h>
18 #include <linux/mm.h>
19 #include <linux/module.h>
20 #include <linux/bitops.h>
21 
22 #include <asm/bcache.h>
23 #include <asm/bootinfo.h>
24 #include <asm/cache.h>
25 #include <asm/cacheops.h>
26 #include <asm/cpu.h>
27 #include <asm/cpu-features.h>
28 #include <asm/cpu-type.h>
29 #include <asm/io.h>
30 #include <asm/page.h>
31 #include <asm/pgtable.h>
32 #include <asm/r4kcache.h>
33 #include <asm/sections.h>
34 #include <asm/mmu_context.h>
35 #include <asm/war.h>
36 #include <asm/cacheflush.h> /* for run_uncached() */
37 #include <asm/traps.h>
38 #include <asm/dma-coherence.h>
39 
40 /*
41  * Special Variant of smp_call_function for use by cache functions:
42  *
43  *  o No return value
44  *  o collapses to normal function call on UP kernels
45  *  o collapses to normal function call on systems with a single shared
46  *    primary cache.
47  *  o doesn't disable interrupts on the local CPU
48  */
49 static inline void r4k_on_each_cpu(void (*func) (void *info), void *info)
50 {
51 	preempt_disable();
52 
53 #if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
54 	smp_call_function(func, info, 1);
55 #endif
56 	func(info);
57 	preempt_enable();
58 }
59 
60 #if defined(CONFIG_MIPS_CMP) || defined(CONFIG_MIPS_CPS)
61 #define cpu_has_safe_index_cacheops 0
62 #else
63 #define cpu_has_safe_index_cacheops 1
64 #endif
65 
66 /*
67  * Must die.
68  */
69 static unsigned long icache_size __read_mostly;
70 static unsigned long dcache_size __read_mostly;
71 static unsigned long scache_size __read_mostly;
72 
73 /*
74  * Dummy cache handling routines for machines without boardcaches
75  */
76 static void cache_noop(void) {}
77 
78 static struct bcache_ops no_sc_ops = {
79 	.bc_enable = (void *)cache_noop,
80 	.bc_disable = (void *)cache_noop,
81 	.bc_wback_inv = (void *)cache_noop,
82 	.bc_inv = (void *)cache_noop
83 };
84 
85 struct bcache_ops *bcops = &no_sc_ops;
86 
87 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
88 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
89 
90 #define R4600_HIT_CACHEOP_WAR_IMPL					\
91 do {									\
92 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
93 		*(volatile unsigned long *)CKSEG1;			\
94 	if (R4600_V1_HIT_CACHEOP_WAR)					\
95 		__asm__ __volatile__("nop;nop;nop;nop");		\
96 } while (0)
97 
98 static void (*r4k_blast_dcache_page)(unsigned long addr);
99 
100 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
101 {
102 	R4600_HIT_CACHEOP_WAR_IMPL;
103 	blast_dcache32_page(addr);
104 }
105 
106 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
107 {
108 	R4600_HIT_CACHEOP_WAR_IMPL;
109 	blast_dcache64_page(addr);
110 }
111 
112 static void r4k_blast_dcache_page_setup(void)
113 {
114 	unsigned long  dc_lsize = cpu_dcache_line_size();
115 
116 	if (dc_lsize == 0)
117 		r4k_blast_dcache_page = (void *)cache_noop;
118 	else if (dc_lsize == 16)
119 		r4k_blast_dcache_page = blast_dcache16_page;
120 	else if (dc_lsize == 32)
121 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
122 	else if (dc_lsize == 64)
123 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
124 }
125 
126 #ifndef CONFIG_EVA
127 #define r4k_blast_dcache_user_page  r4k_blast_dcache_page
128 #else
129 
130 static void (*r4k_blast_dcache_user_page)(unsigned long addr);
131 
132 static void r4k_blast_dcache_user_page_setup(void)
133 {
134 	unsigned long  dc_lsize = cpu_dcache_line_size();
135 
136 	if (dc_lsize == 0)
137 		r4k_blast_dcache_user_page = (void *)cache_noop;
138 	else if (dc_lsize == 16)
139 		r4k_blast_dcache_user_page = blast_dcache16_user_page;
140 	else if (dc_lsize == 32)
141 		r4k_blast_dcache_user_page = blast_dcache32_user_page;
142 	else if (dc_lsize == 64)
143 		r4k_blast_dcache_user_page = blast_dcache64_user_page;
144 }
145 
146 #endif
147 
148 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
149 
150 static void r4k_blast_dcache_page_indexed_setup(void)
151 {
152 	unsigned long dc_lsize = cpu_dcache_line_size();
153 
154 	if (dc_lsize == 0)
155 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
156 	else if (dc_lsize == 16)
157 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
158 	else if (dc_lsize == 32)
159 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
160 	else if (dc_lsize == 64)
161 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
162 }
163 
164 void (* r4k_blast_dcache)(void);
165 EXPORT_SYMBOL(r4k_blast_dcache);
166 
167 static void r4k_blast_dcache_setup(void)
168 {
169 	unsigned long dc_lsize = cpu_dcache_line_size();
170 
171 	if (dc_lsize == 0)
172 		r4k_blast_dcache = (void *)cache_noop;
173 	else if (dc_lsize == 16)
174 		r4k_blast_dcache = blast_dcache16;
175 	else if (dc_lsize == 32)
176 		r4k_blast_dcache = blast_dcache32;
177 	else if (dc_lsize == 64)
178 		r4k_blast_dcache = blast_dcache64;
179 }
180 
181 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
182 #define JUMP_TO_ALIGN(order) \
183 	__asm__ __volatile__( \
184 		"b\t1f\n\t" \
185 		".align\t" #order "\n\t" \
186 		"1:\n\t" \
187 		)
188 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
189 #define CACHE32_UNROLL32_ALIGN2 JUMP_TO_ALIGN(11)
190 
191 static inline void blast_r4600_v1_icache32(void)
192 {
193 	unsigned long flags;
194 
195 	local_irq_save(flags);
196 	blast_icache32();
197 	local_irq_restore(flags);
198 }
199 
200 static inline void tx49_blast_icache32(void)
201 {
202 	unsigned long start = INDEX_BASE;
203 	unsigned long end = start + current_cpu_data.icache.waysize;
204 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
205 	unsigned long ws_end = current_cpu_data.icache.ways <<
206 			       current_cpu_data.icache.waybit;
207 	unsigned long ws, addr;
208 
209 	CACHE32_UNROLL32_ALIGN2;
210 	/* I'm in even chunk.  blast odd chunks */
211 	for (ws = 0; ws < ws_end; ws += ws_inc)
212 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
213 			cache32_unroll32(addr|ws, Index_Invalidate_I);
214 	CACHE32_UNROLL32_ALIGN;
215 	/* I'm in odd chunk.  blast even chunks */
216 	for (ws = 0; ws < ws_end; ws += ws_inc)
217 		for (addr = start; addr < end; addr += 0x400 * 2)
218 			cache32_unroll32(addr|ws, Index_Invalidate_I);
219 }
220 
221 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
222 {
223 	unsigned long flags;
224 
225 	local_irq_save(flags);
226 	blast_icache32_page_indexed(page);
227 	local_irq_restore(flags);
228 }
229 
230 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
231 {
232 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
233 	unsigned long start = INDEX_BASE + (page & indexmask);
234 	unsigned long end = start + PAGE_SIZE;
235 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
236 	unsigned long ws_end = current_cpu_data.icache.ways <<
237 			       current_cpu_data.icache.waybit;
238 	unsigned long ws, addr;
239 
240 	CACHE32_UNROLL32_ALIGN2;
241 	/* I'm in even chunk.  blast odd chunks */
242 	for (ws = 0; ws < ws_end; ws += ws_inc)
243 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
244 			cache32_unroll32(addr|ws, Index_Invalidate_I);
245 	CACHE32_UNROLL32_ALIGN;
246 	/* I'm in odd chunk.  blast even chunks */
247 	for (ws = 0; ws < ws_end; ws += ws_inc)
248 		for (addr = start; addr < end; addr += 0x400 * 2)
249 			cache32_unroll32(addr|ws, Index_Invalidate_I);
250 }
251 
252 static void (* r4k_blast_icache_page)(unsigned long addr);
253 
254 static void r4k_blast_icache_page_setup(void)
255 {
256 	unsigned long ic_lsize = cpu_icache_line_size();
257 
258 	if (ic_lsize == 0)
259 		r4k_blast_icache_page = (void *)cache_noop;
260 	else if (ic_lsize == 16)
261 		r4k_blast_icache_page = blast_icache16_page;
262 	else if (ic_lsize == 32 && current_cpu_type() == CPU_LOONGSON2)
263 		r4k_blast_icache_page = loongson2_blast_icache32_page;
264 	else if (ic_lsize == 32)
265 		r4k_blast_icache_page = blast_icache32_page;
266 	else if (ic_lsize == 64)
267 		r4k_blast_icache_page = blast_icache64_page;
268 }
269 
270 #ifndef CONFIG_EVA
271 #define r4k_blast_icache_user_page  r4k_blast_icache_page
272 #else
273 
274 static void (*r4k_blast_icache_user_page)(unsigned long addr);
275 
276 static void __cpuinit r4k_blast_icache_user_page_setup(void)
277 {
278 	unsigned long ic_lsize = cpu_icache_line_size();
279 
280 	if (ic_lsize == 0)
281 		r4k_blast_icache_user_page = (void *)cache_noop;
282 	else if (ic_lsize == 16)
283 		r4k_blast_icache_user_page = blast_icache16_user_page;
284 	else if (ic_lsize == 32)
285 		r4k_blast_icache_user_page = blast_icache32_user_page;
286 	else if (ic_lsize == 64)
287 		r4k_blast_icache_user_page = blast_icache64_user_page;
288 }
289 
290 #endif
291 
292 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
293 
294 static void r4k_blast_icache_page_indexed_setup(void)
295 {
296 	unsigned long ic_lsize = cpu_icache_line_size();
297 
298 	if (ic_lsize == 0)
299 		r4k_blast_icache_page_indexed = (void *)cache_noop;
300 	else if (ic_lsize == 16)
301 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
302 	else if (ic_lsize == 32) {
303 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
304 			r4k_blast_icache_page_indexed =
305 				blast_icache32_r4600_v1_page_indexed;
306 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
307 			r4k_blast_icache_page_indexed =
308 				tx49_blast_icache32_page_indexed;
309 		else if (current_cpu_type() == CPU_LOONGSON2)
310 			r4k_blast_icache_page_indexed =
311 				loongson2_blast_icache32_page_indexed;
312 		else
313 			r4k_blast_icache_page_indexed =
314 				blast_icache32_page_indexed;
315 	} else if (ic_lsize == 64)
316 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
317 }
318 
319 void (* r4k_blast_icache)(void);
320 EXPORT_SYMBOL(r4k_blast_icache);
321 
322 static void r4k_blast_icache_setup(void)
323 {
324 	unsigned long ic_lsize = cpu_icache_line_size();
325 
326 	if (ic_lsize == 0)
327 		r4k_blast_icache = (void *)cache_noop;
328 	else if (ic_lsize == 16)
329 		r4k_blast_icache = blast_icache16;
330 	else if (ic_lsize == 32) {
331 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
332 			r4k_blast_icache = blast_r4600_v1_icache32;
333 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
334 			r4k_blast_icache = tx49_blast_icache32;
335 		else if (current_cpu_type() == CPU_LOONGSON2)
336 			r4k_blast_icache = loongson2_blast_icache32;
337 		else
338 			r4k_blast_icache = blast_icache32;
339 	} else if (ic_lsize == 64)
340 		r4k_blast_icache = blast_icache64;
341 }
342 
343 static void (* r4k_blast_scache_page)(unsigned long addr);
344 
345 static void r4k_blast_scache_page_setup(void)
346 {
347 	unsigned long sc_lsize = cpu_scache_line_size();
348 
349 	if (scache_size == 0)
350 		r4k_blast_scache_page = (void *)cache_noop;
351 	else if (sc_lsize == 16)
352 		r4k_blast_scache_page = blast_scache16_page;
353 	else if (sc_lsize == 32)
354 		r4k_blast_scache_page = blast_scache32_page;
355 	else if (sc_lsize == 64)
356 		r4k_blast_scache_page = blast_scache64_page;
357 	else if (sc_lsize == 128)
358 		r4k_blast_scache_page = blast_scache128_page;
359 }
360 
361 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
362 
363 static void r4k_blast_scache_page_indexed_setup(void)
364 {
365 	unsigned long sc_lsize = cpu_scache_line_size();
366 
367 	if (scache_size == 0)
368 		r4k_blast_scache_page_indexed = (void *)cache_noop;
369 	else if (sc_lsize == 16)
370 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
371 	else if (sc_lsize == 32)
372 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
373 	else if (sc_lsize == 64)
374 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
375 	else if (sc_lsize == 128)
376 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
377 }
378 
379 static void (* r4k_blast_scache)(void);
380 
381 static void r4k_blast_scache_setup(void)
382 {
383 	unsigned long sc_lsize = cpu_scache_line_size();
384 
385 	if (scache_size == 0)
386 		r4k_blast_scache = (void *)cache_noop;
387 	else if (sc_lsize == 16)
388 		r4k_blast_scache = blast_scache16;
389 	else if (sc_lsize == 32)
390 		r4k_blast_scache = blast_scache32;
391 	else if (sc_lsize == 64)
392 		r4k_blast_scache = blast_scache64;
393 	else if (sc_lsize == 128)
394 		r4k_blast_scache = blast_scache128;
395 }
396 
397 static inline void local_r4k___flush_cache_all(void * args)
398 {
399 	switch (current_cpu_type()) {
400 	case CPU_LOONGSON2:
401 	case CPU_LOONGSON3:
402 	case CPU_R4000SC:
403 	case CPU_R4000MC:
404 	case CPU_R4400SC:
405 	case CPU_R4400MC:
406 	case CPU_R10000:
407 	case CPU_R12000:
408 	case CPU_R14000:
409 		/*
410 		 * These caches are inclusive caches, that is, if something
411 		 * is not cached in the S-cache, we know it also won't be
412 		 * in one of the primary caches.
413 		 */
414 		r4k_blast_scache();
415 		break;
416 
417 	default:
418 		r4k_blast_dcache();
419 		r4k_blast_icache();
420 		break;
421 	}
422 }
423 
424 static void r4k___flush_cache_all(void)
425 {
426 	r4k_on_each_cpu(local_r4k___flush_cache_all, NULL);
427 }
428 
429 static inline int has_valid_asid(const struct mm_struct *mm)
430 {
431 #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
432 	int i;
433 
434 	for_each_online_cpu(i)
435 		if (cpu_context(i, mm))
436 			return 1;
437 
438 	return 0;
439 #else
440 	return cpu_context(smp_processor_id(), mm);
441 #endif
442 }
443 
444 static void r4k__flush_cache_vmap(void)
445 {
446 	r4k_blast_dcache();
447 }
448 
449 static void r4k__flush_cache_vunmap(void)
450 {
451 	r4k_blast_dcache();
452 }
453 
454 static inline void local_r4k_flush_cache_range(void * args)
455 {
456 	struct vm_area_struct *vma = args;
457 	int exec = vma->vm_flags & VM_EXEC;
458 
459 	if (!(has_valid_asid(vma->vm_mm)))
460 		return;
461 
462 	r4k_blast_dcache();
463 	if (exec)
464 		r4k_blast_icache();
465 }
466 
467 static void r4k_flush_cache_range(struct vm_area_struct *vma,
468 	unsigned long start, unsigned long end)
469 {
470 	int exec = vma->vm_flags & VM_EXEC;
471 
472 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
473 		r4k_on_each_cpu(local_r4k_flush_cache_range, vma);
474 }
475 
476 static inline void local_r4k_flush_cache_mm(void * args)
477 {
478 	struct mm_struct *mm = args;
479 
480 	if (!has_valid_asid(mm))
481 		return;
482 
483 	/*
484 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
485 	 * only flush the primary caches but R10000 and R12000 behave sane ...
486 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
487 	 * caches, so we can bail out early.
488 	 */
489 	if (current_cpu_type() == CPU_R4000SC ||
490 	    current_cpu_type() == CPU_R4000MC ||
491 	    current_cpu_type() == CPU_R4400SC ||
492 	    current_cpu_type() == CPU_R4400MC) {
493 		r4k_blast_scache();
494 		return;
495 	}
496 
497 	r4k_blast_dcache();
498 }
499 
500 static void r4k_flush_cache_mm(struct mm_struct *mm)
501 {
502 	if (!cpu_has_dc_aliases)
503 		return;
504 
505 	r4k_on_each_cpu(local_r4k_flush_cache_mm, mm);
506 }
507 
508 struct flush_cache_page_args {
509 	struct vm_area_struct *vma;
510 	unsigned long addr;
511 	unsigned long pfn;
512 };
513 
514 static inline void local_r4k_flush_cache_page(void *args)
515 {
516 	struct flush_cache_page_args *fcp_args = args;
517 	struct vm_area_struct *vma = fcp_args->vma;
518 	unsigned long addr = fcp_args->addr;
519 	struct page *page = pfn_to_page(fcp_args->pfn);
520 	int exec = vma->vm_flags & VM_EXEC;
521 	struct mm_struct *mm = vma->vm_mm;
522 	int map_coherent = 0;
523 	pgd_t *pgdp;
524 	pud_t *pudp;
525 	pmd_t *pmdp;
526 	pte_t *ptep;
527 	void *vaddr;
528 
529 	/*
530 	 * If ownes no valid ASID yet, cannot possibly have gotten
531 	 * this page into the cache.
532 	 */
533 	if (!has_valid_asid(mm))
534 		return;
535 
536 	addr &= PAGE_MASK;
537 	pgdp = pgd_offset(mm, addr);
538 	pudp = pud_offset(pgdp, addr);
539 	pmdp = pmd_offset(pudp, addr);
540 	ptep = pte_offset(pmdp, addr);
541 
542 	/*
543 	 * If the page isn't marked valid, the page cannot possibly be
544 	 * in the cache.
545 	 */
546 	if (!(pte_present(*ptep)))
547 		return;
548 
549 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
550 		vaddr = NULL;
551 	else {
552 		/*
553 		 * Use kmap_coherent or kmap_atomic to do flushes for
554 		 * another ASID than the current one.
555 		 */
556 		map_coherent = (cpu_has_dc_aliases &&
557 				page_mapped(page) && !Page_dcache_dirty(page));
558 		if (map_coherent)
559 			vaddr = kmap_coherent(page, addr);
560 		else
561 			vaddr = kmap_atomic(page);
562 		addr = (unsigned long)vaddr;
563 	}
564 
565 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
566 		vaddr ? r4k_blast_dcache_page(addr) :
567 			r4k_blast_dcache_user_page(addr);
568 		if (exec && !cpu_icache_snoops_remote_store)
569 			r4k_blast_scache_page(addr);
570 	}
571 	if (exec) {
572 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
573 			int cpu = smp_processor_id();
574 
575 			if (cpu_context(cpu, mm) != 0)
576 				drop_mmu_context(mm, cpu);
577 		} else
578 			vaddr ? r4k_blast_icache_page(addr) :
579 				r4k_blast_icache_user_page(addr);
580 	}
581 
582 	if (vaddr) {
583 		if (map_coherent)
584 			kunmap_coherent();
585 		else
586 			kunmap_atomic(vaddr);
587 	}
588 }
589 
590 static void r4k_flush_cache_page(struct vm_area_struct *vma,
591 	unsigned long addr, unsigned long pfn)
592 {
593 	struct flush_cache_page_args args;
594 
595 	args.vma = vma;
596 	args.addr = addr;
597 	args.pfn = pfn;
598 
599 	r4k_on_each_cpu(local_r4k_flush_cache_page, &args);
600 }
601 
602 static inline void local_r4k_flush_data_cache_page(void * addr)
603 {
604 	r4k_blast_dcache_page((unsigned long) addr);
605 }
606 
607 static void r4k_flush_data_cache_page(unsigned long addr)
608 {
609 	if (in_atomic())
610 		local_r4k_flush_data_cache_page((void *)addr);
611 	else
612 		r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr);
613 }
614 
615 struct flush_icache_range_args {
616 	unsigned long start;
617 	unsigned long end;
618 };
619 
620 static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
621 {
622 	if (!cpu_has_ic_fills_f_dc) {
623 		if (end - start >= dcache_size) {
624 			r4k_blast_dcache();
625 		} else {
626 			R4600_HIT_CACHEOP_WAR_IMPL;
627 			protected_blast_dcache_range(start, end);
628 		}
629 	}
630 
631 	if (end - start > icache_size)
632 		r4k_blast_icache();
633 	else {
634 		switch (boot_cpu_type()) {
635 		case CPU_LOONGSON2:
636 			protected_loongson2_blast_icache_range(start, end);
637 			break;
638 
639 		default:
640 			protected_blast_icache_range(start, end);
641 			break;
642 		}
643 	}
644 #ifdef CONFIG_EVA
645 	/*
646 	 * Due to all possible segment mappings, there might cache aliases
647 	 * caused by the bootloader being in non-EVA mode, and the CPU switching
648 	 * to EVA during early kernel init. It's best to flush the scache
649 	 * to avoid having secondary cores fetching stale data and lead to
650 	 * kernel crashes.
651 	 */
652 	bc_wback_inv(start, (end - start));
653 	__sync();
654 #endif
655 }
656 
657 static inline void local_r4k_flush_icache_range_ipi(void *args)
658 {
659 	struct flush_icache_range_args *fir_args = args;
660 	unsigned long start = fir_args->start;
661 	unsigned long end = fir_args->end;
662 
663 	local_r4k_flush_icache_range(start, end);
664 }
665 
666 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
667 {
668 	struct flush_icache_range_args args;
669 
670 	args.start = start;
671 	args.end = end;
672 
673 	r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args);
674 	instruction_hazard();
675 }
676 
677 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
678 
679 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
680 {
681 	/* Catch bad driver code */
682 	BUG_ON(size == 0);
683 
684 	preempt_disable();
685 	if (cpu_has_inclusive_pcaches) {
686 		if (size >= scache_size)
687 			r4k_blast_scache();
688 		else
689 			blast_scache_range(addr, addr + size);
690 		preempt_enable();
691 		__sync();
692 		return;
693 	}
694 
695 	/*
696 	 * Either no secondary cache or the available caches don't have the
697 	 * subset property so we have to flush the primary caches
698 	 * explicitly
699 	 */
700 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
701 		r4k_blast_dcache();
702 	} else {
703 		R4600_HIT_CACHEOP_WAR_IMPL;
704 		blast_dcache_range(addr, addr + size);
705 	}
706 	preempt_enable();
707 
708 	bc_wback_inv(addr, size);
709 	__sync();
710 }
711 
712 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
713 {
714 	/* Catch bad driver code */
715 	BUG_ON(size == 0);
716 
717 	preempt_disable();
718 	if (cpu_has_inclusive_pcaches) {
719 		if (size >= scache_size)
720 			r4k_blast_scache();
721 		else {
722 			/*
723 			 * There is no clearly documented alignment requirement
724 			 * for the cache instruction on MIPS processors and
725 			 * some processors, among them the RM5200 and RM7000
726 			 * QED processors will throw an address error for cache
727 			 * hit ops with insufficient alignment.	 Solved by
728 			 * aligning the address to cache line size.
729 			 */
730 			blast_inv_scache_range(addr, addr + size);
731 		}
732 		preempt_enable();
733 		__sync();
734 		return;
735 	}
736 
737 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
738 		r4k_blast_dcache();
739 	} else {
740 		R4600_HIT_CACHEOP_WAR_IMPL;
741 		blast_inv_dcache_range(addr, addr + size);
742 	}
743 	preempt_enable();
744 
745 	bc_inv(addr, size);
746 	__sync();
747 }
748 #endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
749 
750 /*
751  * While we're protected against bad userland addresses we don't care
752  * very much about what happens in that case.  Usually a segmentation
753  * fault will dump the process later on anyway ...
754  */
755 static void local_r4k_flush_cache_sigtramp(void * arg)
756 {
757 	unsigned long ic_lsize = cpu_icache_line_size();
758 	unsigned long dc_lsize = cpu_dcache_line_size();
759 	unsigned long sc_lsize = cpu_scache_line_size();
760 	unsigned long addr = (unsigned long) arg;
761 
762 	R4600_HIT_CACHEOP_WAR_IMPL;
763 	if (dc_lsize)
764 		protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
765 	if (!cpu_icache_snoops_remote_store && scache_size)
766 		protected_writeback_scache_line(addr & ~(sc_lsize - 1));
767 	if (ic_lsize)
768 		protected_flush_icache_line(addr & ~(ic_lsize - 1));
769 	if (MIPS4K_ICACHE_REFILL_WAR) {
770 		__asm__ __volatile__ (
771 			".set push\n\t"
772 			".set noat\n\t"
773 			".set mips3\n\t"
774 #ifdef CONFIG_32BIT
775 			"la	$at,1f\n\t"
776 #endif
777 #ifdef CONFIG_64BIT
778 			"dla	$at,1f\n\t"
779 #endif
780 			"cache	%0,($at)\n\t"
781 			"nop; nop; nop\n"
782 			"1:\n\t"
783 			".set pop"
784 			:
785 			: "i" (Hit_Invalidate_I));
786 	}
787 	if (MIPS_CACHE_SYNC_WAR)
788 		__asm__ __volatile__ ("sync");
789 }
790 
791 static void r4k_flush_cache_sigtramp(unsigned long addr)
792 {
793 	r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr);
794 }
795 
796 static void r4k_flush_icache_all(void)
797 {
798 	if (cpu_has_vtag_icache)
799 		r4k_blast_icache();
800 }
801 
802 struct flush_kernel_vmap_range_args {
803 	unsigned long	vaddr;
804 	int		size;
805 };
806 
807 static inline void local_r4k_flush_kernel_vmap_range(void *args)
808 {
809 	struct flush_kernel_vmap_range_args *vmra = args;
810 	unsigned long vaddr = vmra->vaddr;
811 	int size = vmra->size;
812 
813 	/*
814 	 * Aliases only affect the primary caches so don't bother with
815 	 * S-caches or T-caches.
816 	 */
817 	if (cpu_has_safe_index_cacheops && size >= dcache_size)
818 		r4k_blast_dcache();
819 	else {
820 		R4600_HIT_CACHEOP_WAR_IMPL;
821 		blast_dcache_range(vaddr, vaddr + size);
822 	}
823 }
824 
825 static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
826 {
827 	struct flush_kernel_vmap_range_args args;
828 
829 	args.vaddr = (unsigned long) vaddr;
830 	args.size = size;
831 
832 	r4k_on_each_cpu(local_r4k_flush_kernel_vmap_range, &args);
833 }
834 
835 static inline void rm7k_erratum31(void)
836 {
837 	const unsigned long ic_lsize = 32;
838 	unsigned long addr;
839 
840 	/* RM7000 erratum #31. The icache is screwed at startup. */
841 	write_c0_taglo(0);
842 	write_c0_taghi(0);
843 
844 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
845 		__asm__ __volatile__ (
846 			".set push\n\t"
847 			".set noreorder\n\t"
848 			".set mips3\n\t"
849 			"cache\t%1, 0(%0)\n\t"
850 			"cache\t%1, 0x1000(%0)\n\t"
851 			"cache\t%1, 0x2000(%0)\n\t"
852 			"cache\t%1, 0x3000(%0)\n\t"
853 			"cache\t%2, 0(%0)\n\t"
854 			"cache\t%2, 0x1000(%0)\n\t"
855 			"cache\t%2, 0x2000(%0)\n\t"
856 			"cache\t%2, 0x3000(%0)\n\t"
857 			"cache\t%1, 0(%0)\n\t"
858 			"cache\t%1, 0x1000(%0)\n\t"
859 			"cache\t%1, 0x2000(%0)\n\t"
860 			"cache\t%1, 0x3000(%0)\n\t"
861 			".set pop\n"
862 			:
863 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
864 	}
865 }
866 
867 static inline void alias_74k_erratum(struct cpuinfo_mips *c)
868 {
869 	unsigned int imp = c->processor_id & PRID_IMP_MASK;
870 	unsigned int rev = c->processor_id & PRID_REV_MASK;
871 
872 	/*
873 	 * Early versions of the 74K do not update the cache tags on a
874 	 * vtag miss/ptag hit which can occur in the case of KSEG0/KUSEG
875 	 * aliases. In this case it is better to treat the cache as always
876 	 * having aliases.
877 	 */
878 	switch (imp) {
879 	case PRID_IMP_74K:
880 		if (rev <= PRID_REV_ENCODE_332(2, 4, 0))
881 			c->dcache.flags |= MIPS_CACHE_VTAG;
882 		if (rev == PRID_REV_ENCODE_332(2, 4, 0))
883 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
884 		break;
885 	case PRID_IMP_1074K:
886 		if (rev <= PRID_REV_ENCODE_332(1, 1, 0)) {
887 			c->dcache.flags |= MIPS_CACHE_VTAG;
888 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
889 		}
890 		break;
891 	default:
892 		BUG();
893 	}
894 }
895 
896 static char *way_string[] = { NULL, "direct mapped", "2-way",
897 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
898 };
899 
900 static void probe_pcache(void)
901 {
902 	struct cpuinfo_mips *c = &current_cpu_data;
903 	unsigned int config = read_c0_config();
904 	unsigned int prid = read_c0_prid();
905 	unsigned long config1;
906 	unsigned int lsize;
907 
908 	switch (current_cpu_type()) {
909 	case CPU_R4600:			/* QED style two way caches? */
910 	case CPU_R4700:
911 	case CPU_R5000:
912 	case CPU_NEVADA:
913 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
914 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
915 		c->icache.ways = 2;
916 		c->icache.waybit = __ffs(icache_size/2);
917 
918 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
919 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
920 		c->dcache.ways = 2;
921 		c->dcache.waybit= __ffs(dcache_size/2);
922 
923 		c->options |= MIPS_CPU_CACHE_CDEX_P;
924 		break;
925 
926 	case CPU_R5432:
927 	case CPU_R5500:
928 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
929 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
930 		c->icache.ways = 2;
931 		c->icache.waybit= 0;
932 
933 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
934 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
935 		c->dcache.ways = 2;
936 		c->dcache.waybit = 0;
937 
938 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
939 		break;
940 
941 	case CPU_TX49XX:
942 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
943 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
944 		c->icache.ways = 4;
945 		c->icache.waybit= 0;
946 
947 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
948 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
949 		c->dcache.ways = 4;
950 		c->dcache.waybit = 0;
951 
952 		c->options |= MIPS_CPU_CACHE_CDEX_P;
953 		c->options |= MIPS_CPU_PREFETCH;
954 		break;
955 
956 	case CPU_R4000PC:
957 	case CPU_R4000SC:
958 	case CPU_R4000MC:
959 	case CPU_R4400PC:
960 	case CPU_R4400SC:
961 	case CPU_R4400MC:
962 	case CPU_R4300:
963 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
964 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
965 		c->icache.ways = 1;
966 		c->icache.waybit = 0;	/* doesn't matter */
967 
968 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
969 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
970 		c->dcache.ways = 1;
971 		c->dcache.waybit = 0;	/* does not matter */
972 
973 		c->options |= MIPS_CPU_CACHE_CDEX_P;
974 		break;
975 
976 	case CPU_R10000:
977 	case CPU_R12000:
978 	case CPU_R14000:
979 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
980 		c->icache.linesz = 64;
981 		c->icache.ways = 2;
982 		c->icache.waybit = 0;
983 
984 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
985 		c->dcache.linesz = 32;
986 		c->dcache.ways = 2;
987 		c->dcache.waybit = 0;
988 
989 		c->options |= MIPS_CPU_PREFETCH;
990 		break;
991 
992 	case CPU_VR4133:
993 		write_c0_config(config & ~VR41_CONF_P4K);
994 	case CPU_VR4131:
995 		/* Workaround for cache instruction bug of VR4131 */
996 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
997 		    c->processor_id == 0x0c82U) {
998 			config |= 0x00400000U;
999 			if (c->processor_id == 0x0c80U)
1000 				config |= VR41_CONF_BP;
1001 			write_c0_config(config);
1002 		} else
1003 			c->options |= MIPS_CPU_CACHE_CDEX_P;
1004 
1005 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
1006 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1007 		c->icache.ways = 2;
1008 		c->icache.waybit = __ffs(icache_size/2);
1009 
1010 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
1011 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1012 		c->dcache.ways = 2;
1013 		c->dcache.waybit = __ffs(dcache_size/2);
1014 		break;
1015 
1016 	case CPU_VR41XX:
1017 	case CPU_VR4111:
1018 	case CPU_VR4121:
1019 	case CPU_VR4122:
1020 	case CPU_VR4181:
1021 	case CPU_VR4181A:
1022 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
1023 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1024 		c->icache.ways = 1;
1025 		c->icache.waybit = 0;	/* doesn't matter */
1026 
1027 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
1028 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1029 		c->dcache.ways = 1;
1030 		c->dcache.waybit = 0;	/* does not matter */
1031 
1032 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1033 		break;
1034 
1035 	case CPU_RM7000:
1036 		rm7k_erratum31();
1037 
1038 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1039 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1040 		c->icache.ways = 4;
1041 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
1042 
1043 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1044 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1045 		c->dcache.ways = 4;
1046 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
1047 
1048 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1049 		c->options |= MIPS_CPU_PREFETCH;
1050 		break;
1051 
1052 	case CPU_LOONGSON2:
1053 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1054 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1055 		if (prid & 0x3)
1056 			c->icache.ways = 4;
1057 		else
1058 			c->icache.ways = 2;
1059 		c->icache.waybit = 0;
1060 
1061 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1062 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1063 		if (prid & 0x3)
1064 			c->dcache.ways = 4;
1065 		else
1066 			c->dcache.ways = 2;
1067 		c->dcache.waybit = 0;
1068 		break;
1069 
1070 	case CPU_LOONGSON3:
1071 		config1 = read_c0_config1();
1072 		lsize = (config1 >> 19) & 7;
1073 		if (lsize)
1074 			c->icache.linesz = 2 << lsize;
1075 		else
1076 			c->icache.linesz = 0;
1077 		c->icache.sets = 64 << ((config1 >> 22) & 7);
1078 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1079 		icache_size = c->icache.sets *
1080 					  c->icache.ways *
1081 					  c->icache.linesz;
1082 		c->icache.waybit = 0;
1083 
1084 		lsize = (config1 >> 10) & 7;
1085 		if (lsize)
1086 			c->dcache.linesz = 2 << lsize;
1087 		else
1088 			c->dcache.linesz = 0;
1089 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
1090 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1091 		dcache_size = c->dcache.sets *
1092 					  c->dcache.ways *
1093 					  c->dcache.linesz;
1094 		c->dcache.waybit = 0;
1095 		break;
1096 
1097 	default:
1098 		if (!(config & MIPS_CONF_M))
1099 			panic("Don't know how to probe P-caches on this cpu.");
1100 
1101 		/*
1102 		 * So we seem to be a MIPS32 or MIPS64 CPU
1103 		 * So let's probe the I-cache ...
1104 		 */
1105 		config1 = read_c0_config1();
1106 
1107 		lsize = (config1 >> 19) & 7;
1108 
1109 		/* IL == 7 is reserved */
1110 		if (lsize == 7)
1111 			panic("Invalid icache line size");
1112 
1113 		c->icache.linesz = lsize ? 2 << lsize : 0;
1114 
1115 		c->icache.sets = 32 << (((config1 >> 22) + 1) & 7);
1116 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1117 
1118 		icache_size = c->icache.sets *
1119 			      c->icache.ways *
1120 			      c->icache.linesz;
1121 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
1122 
1123 		if (config & 0x8)		/* VI bit */
1124 			c->icache.flags |= MIPS_CACHE_VTAG;
1125 
1126 		/*
1127 		 * Now probe the MIPS32 / MIPS64 data cache.
1128 		 */
1129 		c->dcache.flags = 0;
1130 
1131 		lsize = (config1 >> 10) & 7;
1132 
1133 		/* DL == 7 is reserved */
1134 		if (lsize == 7)
1135 			panic("Invalid dcache line size");
1136 
1137 		c->dcache.linesz = lsize ? 2 << lsize : 0;
1138 
1139 		c->dcache.sets = 32 << (((config1 >> 13) + 1) & 7);
1140 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1141 
1142 		dcache_size = c->dcache.sets *
1143 			      c->dcache.ways *
1144 			      c->dcache.linesz;
1145 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
1146 
1147 		c->options |= MIPS_CPU_PREFETCH;
1148 		break;
1149 	}
1150 
1151 	/*
1152 	 * Processor configuration sanity check for the R4000SC erratum
1153 	 * #5.	With page sizes larger than 32kB there is no possibility
1154 	 * to get a VCE exception anymore so we don't care about this
1155 	 * misconfiguration.  The case is rather theoretical anyway;
1156 	 * presumably no vendor is shipping his hardware in the "bad"
1157 	 * configuration.
1158 	 */
1159 	if ((prid & PRID_IMP_MASK) == PRID_IMP_R4000 &&
1160 	    (prid & PRID_REV_MASK) < PRID_REV_R4400 &&
1161 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
1162 	    PAGE_SIZE <= 0x8000)
1163 		panic("Improper R4000SC processor configuration detected");
1164 
1165 	/* compute a couple of other cache variables */
1166 	c->icache.waysize = icache_size / c->icache.ways;
1167 	c->dcache.waysize = dcache_size / c->dcache.ways;
1168 
1169 	c->icache.sets = c->icache.linesz ?
1170 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
1171 	c->dcache.sets = c->dcache.linesz ?
1172 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
1173 
1174 	/*
1175 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
1176 	 * 2-way virtually indexed so normally would suffer from aliases.  So
1177 	 * normally they'd suffer from aliases but magic in the hardware deals
1178 	 * with that for us so we don't need to take care ourselves.
1179 	 */
1180 	switch (current_cpu_type()) {
1181 	case CPU_20KC:
1182 	case CPU_25KF:
1183 	case CPU_SB1:
1184 	case CPU_SB1A:
1185 	case CPU_XLR:
1186 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1187 		break;
1188 
1189 	case CPU_R10000:
1190 	case CPU_R12000:
1191 	case CPU_R14000:
1192 		break;
1193 
1194 	case CPU_M14KC:
1195 	case CPU_M14KEC:
1196 	case CPU_24K:
1197 	case CPU_34K:
1198 	case CPU_74K:
1199 	case CPU_1004K:
1200 	case CPU_1074K:
1201 	case CPU_INTERAPTIV:
1202 	case CPU_P5600:
1203 	case CPU_PROAPTIV:
1204 	case CPU_M5150:
1205 		if ((c->cputype == CPU_74K) || (c->cputype == CPU_1074K))
1206 			alias_74k_erratum(c);
1207 		if (!(read_c0_config7() & MIPS_CONF7_IAR) &&
1208 		    (c->icache.waysize > PAGE_SIZE))
1209 			c->icache.flags |= MIPS_CACHE_ALIASES;
1210 		if (read_c0_config7() & MIPS_CONF7_AR) {
1211 			/*
1212 			 * Effectively physically indexed dcache,
1213 			 * thus no virtual aliases.
1214 			*/
1215 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1216 			break;
1217 		}
1218 	default:
1219 		if (c->dcache.waysize > PAGE_SIZE)
1220 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1221 	}
1222 
1223 	switch (current_cpu_type()) {
1224 	case CPU_20KC:
1225 		/*
1226 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1227 		 * the config register.
1228 		 */
1229 		c->icache.flags |= MIPS_CACHE_VTAG;
1230 		break;
1231 
1232 	case CPU_ALCHEMY:
1233 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1234 		break;
1235 
1236 	case CPU_LOONGSON2:
1237 		/*
1238 		 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1239 		 * one op will act on all 4 ways
1240 		 */
1241 		c->icache.ways = 1;
1242 	}
1243 
1244 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1245 	       icache_size >> 10,
1246 	       c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1247 	       way_string[c->icache.ways], c->icache.linesz);
1248 
1249 	printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1250 	       dcache_size >> 10, way_string[c->dcache.ways],
1251 	       (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1252 	       (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1253 			"cache aliases" : "no aliases",
1254 	       c->dcache.linesz);
1255 }
1256 
1257 /*
1258  * If you even _breathe_ on this function, look at the gcc output and make sure
1259  * it does not pop things on and off the stack for the cache sizing loop that
1260  * executes in KSEG1 space or else you will crash and burn badly.  You have
1261  * been warned.
1262  */
1263 static int probe_scache(void)
1264 {
1265 	unsigned long flags, addr, begin, end, pow2;
1266 	unsigned int config = read_c0_config();
1267 	struct cpuinfo_mips *c = &current_cpu_data;
1268 
1269 	if (config & CONF_SC)
1270 		return 0;
1271 
1272 	begin = (unsigned long) &_stext;
1273 	begin &= ~((4 * 1024 * 1024) - 1);
1274 	end = begin + (4 * 1024 * 1024);
1275 
1276 	/*
1277 	 * This is such a bitch, you'd think they would make it easy to do
1278 	 * this.  Away you daemons of stupidity!
1279 	 */
1280 	local_irq_save(flags);
1281 
1282 	/* Fill each size-multiple cache line with a valid tag. */
1283 	pow2 = (64 * 1024);
1284 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1285 		unsigned long *p = (unsigned long *) addr;
1286 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1287 		pow2 <<= 1;
1288 	}
1289 
1290 	/* Load first line with zero (therefore invalid) tag. */
1291 	write_c0_taglo(0);
1292 	write_c0_taghi(0);
1293 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1294 	cache_op(Index_Store_Tag_I, begin);
1295 	cache_op(Index_Store_Tag_D, begin);
1296 	cache_op(Index_Store_Tag_SD, begin);
1297 
1298 	/* Now search for the wrap around point. */
1299 	pow2 = (128 * 1024);
1300 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1301 		cache_op(Index_Load_Tag_SD, addr);
1302 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1303 		if (!read_c0_taglo())
1304 			break;
1305 		pow2 <<= 1;
1306 	}
1307 	local_irq_restore(flags);
1308 	addr -= begin;
1309 
1310 	scache_size = addr;
1311 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1312 	c->scache.ways = 1;
1313 	c->dcache.waybit = 0;		/* does not matter */
1314 
1315 	return 1;
1316 }
1317 
1318 static void __init loongson2_sc_init(void)
1319 {
1320 	struct cpuinfo_mips *c = &current_cpu_data;
1321 
1322 	scache_size = 512*1024;
1323 	c->scache.linesz = 32;
1324 	c->scache.ways = 4;
1325 	c->scache.waybit = 0;
1326 	c->scache.waysize = scache_size / (c->scache.ways);
1327 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1328 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1329 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1330 
1331 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1332 }
1333 
1334 static void __init loongson3_sc_init(void)
1335 {
1336 	struct cpuinfo_mips *c = &current_cpu_data;
1337 	unsigned int config2, lsize;
1338 
1339 	config2 = read_c0_config2();
1340 	lsize = (config2 >> 4) & 15;
1341 	if (lsize)
1342 		c->scache.linesz = 2 << lsize;
1343 	else
1344 		c->scache.linesz = 0;
1345 	c->scache.sets = 64 << ((config2 >> 8) & 15);
1346 	c->scache.ways = 1 + (config2 & 15);
1347 
1348 	scache_size = c->scache.sets *
1349 				  c->scache.ways *
1350 				  c->scache.linesz;
1351 	/* Loongson-3 has 4 cores, 1MB scache for each. scaches are shared */
1352 	scache_size *= 4;
1353 	c->scache.waybit = 0;
1354 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1355 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1356 	if (scache_size)
1357 		c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1358 	return;
1359 }
1360 
1361 extern int r5k_sc_init(void);
1362 extern int rm7k_sc_init(void);
1363 extern int mips_sc_init(void);
1364 
1365 static void setup_scache(void)
1366 {
1367 	struct cpuinfo_mips *c = &current_cpu_data;
1368 	unsigned int config = read_c0_config();
1369 	int sc_present = 0;
1370 
1371 	/*
1372 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1373 	 * processors don't have a S-cache that would be relevant to the
1374 	 * Linux memory management.
1375 	 */
1376 	switch (current_cpu_type()) {
1377 	case CPU_R4000SC:
1378 	case CPU_R4000MC:
1379 	case CPU_R4400SC:
1380 	case CPU_R4400MC:
1381 		sc_present = run_uncached(probe_scache);
1382 		if (sc_present)
1383 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1384 		break;
1385 
1386 	case CPU_R10000:
1387 	case CPU_R12000:
1388 	case CPU_R14000:
1389 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1390 		c->scache.linesz = 64 << ((config >> 13) & 1);
1391 		c->scache.ways = 2;
1392 		c->scache.waybit= 0;
1393 		sc_present = 1;
1394 		break;
1395 
1396 	case CPU_R5000:
1397 	case CPU_NEVADA:
1398 #ifdef CONFIG_R5000_CPU_SCACHE
1399 		r5k_sc_init();
1400 #endif
1401 		return;
1402 
1403 	case CPU_RM7000:
1404 #ifdef CONFIG_RM7000_CPU_SCACHE
1405 		rm7k_sc_init();
1406 #endif
1407 		return;
1408 
1409 	case CPU_LOONGSON2:
1410 		loongson2_sc_init();
1411 		return;
1412 
1413 	case CPU_LOONGSON3:
1414 		loongson3_sc_init();
1415 		return;
1416 
1417 	case CPU_XLP:
1418 		/* don't need to worry about L2, fully coherent */
1419 		return;
1420 
1421 	default:
1422 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M32R2 |
1423 				    MIPS_CPU_ISA_M64R1 | MIPS_CPU_ISA_M64R2)) {
1424 #ifdef CONFIG_MIPS_CPU_SCACHE
1425 			if (mips_sc_init ()) {
1426 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1427 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1428 				       scache_size >> 10,
1429 				       way_string[c->scache.ways], c->scache.linesz);
1430 			}
1431 #else
1432 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1433 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1434 #endif
1435 			return;
1436 		}
1437 		sc_present = 0;
1438 	}
1439 
1440 	if (!sc_present)
1441 		return;
1442 
1443 	/* compute a couple of other cache variables */
1444 	c->scache.waysize = scache_size / c->scache.ways;
1445 
1446 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1447 
1448 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1449 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1450 
1451 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1452 }
1453 
1454 void au1x00_fixup_config_od(void)
1455 {
1456 	/*
1457 	 * c0_config.od (bit 19) was write only (and read as 0)
1458 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1459 	 * transaction overlapping and needs to be set to fix various errata.
1460 	 */
1461 	switch (read_c0_prid()) {
1462 	case 0x00030100: /* Au1000 DA */
1463 	case 0x00030201: /* Au1000 HA */
1464 	case 0x00030202: /* Au1000 HB */
1465 	case 0x01030200: /* Au1500 AB */
1466 	/*
1467 	 * Au1100 errata actually keeps silence about this bit, so we set it
1468 	 * just in case for those revisions that require it to be set according
1469 	 * to the (now gone) cpu table.
1470 	 */
1471 	case 0x02030200: /* Au1100 AB */
1472 	case 0x02030201: /* Au1100 BA */
1473 	case 0x02030202: /* Au1100 BC */
1474 		set_c0_config(1 << 19);
1475 		break;
1476 	}
1477 }
1478 
1479 /* CP0 hazard avoidance. */
1480 #define NXP_BARRIER()							\
1481 	 __asm__ __volatile__(						\
1482 	".set noreorder\n\t"						\
1483 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1484 	".set reorder\n\t")
1485 
1486 static void nxp_pr4450_fixup_config(void)
1487 {
1488 	unsigned long config0;
1489 
1490 	config0 = read_c0_config();
1491 
1492 	/* clear all three cache coherency fields */
1493 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1494 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1495 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1496 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1497 	write_c0_config(config0);
1498 	NXP_BARRIER();
1499 }
1500 
1501 static int cca = -1;
1502 
1503 static int __init cca_setup(char *str)
1504 {
1505 	get_option(&str, &cca);
1506 
1507 	return 0;
1508 }
1509 
1510 early_param("cca", cca_setup);
1511 
1512 static void coherency_setup(void)
1513 {
1514 	if (cca < 0 || cca > 7)
1515 		cca = read_c0_config() & CONF_CM_CMASK;
1516 	_page_cachable_default = cca << _CACHE_SHIFT;
1517 
1518 	pr_debug("Using cache attribute %d\n", cca);
1519 	change_c0_config(CONF_CM_CMASK, cca);
1520 
1521 	/*
1522 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1523 	 * the coherency mode specified by the TLB; 1 means cachable
1524 	 * coherent update on write will be used.  Not all processors have
1525 	 * this bit and; some wire it to zero, others like Toshiba had the
1526 	 * silly idea of putting something else there ...
1527 	 */
1528 	switch (current_cpu_type()) {
1529 	case CPU_R4000PC:
1530 	case CPU_R4000SC:
1531 	case CPU_R4000MC:
1532 	case CPU_R4400PC:
1533 	case CPU_R4400SC:
1534 	case CPU_R4400MC:
1535 		clear_c0_config(CONF_CU);
1536 		break;
1537 	/*
1538 	 * We need to catch the early Alchemy SOCs with
1539 	 * the write-only co_config.od bit and set it back to one on:
1540 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1541 	 */
1542 	case CPU_ALCHEMY:
1543 		au1x00_fixup_config_od();
1544 		break;
1545 
1546 	case PRID_IMP_PR4450:
1547 		nxp_pr4450_fixup_config();
1548 		break;
1549 	}
1550 }
1551 
1552 static void r4k_cache_error_setup(void)
1553 {
1554 	extern char __weak except_vec2_generic;
1555 	extern char __weak except_vec2_sb1;
1556 
1557 	switch (current_cpu_type()) {
1558 	case CPU_SB1:
1559 	case CPU_SB1A:
1560 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1561 		break;
1562 
1563 	default:
1564 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1565 		break;
1566 	}
1567 }
1568 
1569 void r4k_cache_init(void)
1570 {
1571 	extern void build_clear_page(void);
1572 	extern void build_copy_page(void);
1573 	struct cpuinfo_mips *c = &current_cpu_data;
1574 
1575 	probe_pcache();
1576 	setup_scache();
1577 
1578 	r4k_blast_dcache_page_setup();
1579 	r4k_blast_dcache_page_indexed_setup();
1580 	r4k_blast_dcache_setup();
1581 	r4k_blast_icache_page_setup();
1582 	r4k_blast_icache_page_indexed_setup();
1583 	r4k_blast_icache_setup();
1584 	r4k_blast_scache_page_setup();
1585 	r4k_blast_scache_page_indexed_setup();
1586 	r4k_blast_scache_setup();
1587 #ifdef CONFIG_EVA
1588 	r4k_blast_dcache_user_page_setup();
1589 	r4k_blast_icache_user_page_setup();
1590 #endif
1591 
1592 	/*
1593 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1594 	 * This code supports virtually indexed processors and will be
1595 	 * unnecessarily inefficient on physically indexed processors.
1596 	 */
1597 	if (c->dcache.linesz)
1598 		shm_align_mask = max_t( unsigned long,
1599 					c->dcache.sets * c->dcache.linesz - 1,
1600 					PAGE_SIZE - 1);
1601 	else
1602 		shm_align_mask = PAGE_SIZE-1;
1603 
1604 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1605 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1606 
1607 	flush_cache_all		= cache_noop;
1608 	__flush_cache_all	= r4k___flush_cache_all;
1609 	flush_cache_mm		= r4k_flush_cache_mm;
1610 	flush_cache_page	= r4k_flush_cache_page;
1611 	flush_cache_range	= r4k_flush_cache_range;
1612 
1613 	__flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1614 
1615 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1616 	flush_icache_all	= r4k_flush_icache_all;
1617 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1618 	flush_data_cache_page	= r4k_flush_data_cache_page;
1619 	flush_icache_range	= r4k_flush_icache_range;
1620 	local_flush_icache_range	= local_r4k_flush_icache_range;
1621 
1622 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
1623 	if (coherentio) {
1624 		_dma_cache_wback_inv	= (void *)cache_noop;
1625 		_dma_cache_wback	= (void *)cache_noop;
1626 		_dma_cache_inv		= (void *)cache_noop;
1627 	} else {
1628 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1629 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1630 		_dma_cache_inv		= r4k_dma_cache_inv;
1631 	}
1632 #endif
1633 
1634 	build_clear_page();
1635 	build_copy_page();
1636 
1637 	/*
1638 	 * We want to run CMP kernels on core with and without coherent
1639 	 * caches. Therefore, do not use CONFIG_MIPS_CMP to decide whether
1640 	 * or not to flush caches.
1641 	 */
1642 	local_r4k___flush_cache_all(NULL);
1643 
1644 	coherency_setup();
1645 	board_cache_error_setup = r4k_cache_error_setup;
1646 }
1647