xref: /linux/arch/mips/mm/c-r4k.c (revision b68fc09be48edbc47de1a0f3d42ef8adf6c0ac55)
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/cpu_pm.h>
11 #include <linux/hardirq.h>
12 #include <linux/init.h>
13 #include <linux/highmem.h>
14 #include <linux/kernel.h>
15 #include <linux/linkage.h>
16 #include <linux/preempt.h>
17 #include <linux/sched.h>
18 #include <linux/smp.h>
19 #include <linux/mm.h>
20 #include <linux/export.h>
21 #include <linux/bitops.h>
22 
23 #include <asm/bcache.h>
24 #include <asm/bootinfo.h>
25 #include <asm/cache.h>
26 #include <asm/cacheops.h>
27 #include <asm/cpu.h>
28 #include <asm/cpu-features.h>
29 #include <asm/cpu-type.h>
30 #include <asm/io.h>
31 #include <asm/page.h>
32 #include <asm/pgtable.h>
33 #include <asm/r4kcache.h>
34 #include <asm/sections.h>
35 #include <asm/mmu_context.h>
36 #include <asm/war.h>
37 #include <asm/cacheflush.h> /* for run_uncached() */
38 #include <asm/traps.h>
39 #include <asm/dma-coherence.h>
40 #include <asm/mips-cps.h>
41 
42 /*
43  * Bits describing what cache ops an SMP callback function may perform.
44  *
45  * R4K_HIT   -	Virtual user or kernel address based cache operations. The
46  *		active_mm must be checked before using user addresses, falling
47  *		back to kmap.
48  * R4K_INDEX -	Index based cache operations.
49  */
50 
51 #define R4K_HIT		BIT(0)
52 #define R4K_INDEX	BIT(1)
53 
54 /**
55  * r4k_op_needs_ipi() - Decide if a cache op needs to be done on every core.
56  * @type:	Type of cache operations (R4K_HIT or R4K_INDEX).
57  *
58  * Decides whether a cache op needs to be performed on every core in the system.
59  * This may change depending on the @type of cache operation, as well as the set
60  * of online CPUs, so preemption should be disabled by the caller to prevent CPU
61  * hotplug from changing the result.
62  *
63  * Returns:	1 if the cache operation @type should be done on every core in
64  *		the system.
65  *		0 if the cache operation @type is globalized and only needs to
66  *		be performed on a simple CPU.
67  */
68 static inline bool r4k_op_needs_ipi(unsigned int type)
69 {
70 	/* The MIPS Coherence Manager (CM) globalizes address-based cache ops */
71 	if (type == R4K_HIT && mips_cm_present())
72 		return false;
73 
74 	/*
75 	 * Hardware doesn't globalize the required cache ops, so SMP calls may
76 	 * be needed, but only if there are foreign CPUs (non-siblings with
77 	 * separate caches).
78 	 */
79 	/* cpu_foreign_map[] undeclared when !CONFIG_SMP */
80 #ifdef CONFIG_SMP
81 	return !cpumask_empty(&cpu_foreign_map[0]);
82 #else
83 	return false;
84 #endif
85 }
86 
87 /*
88  * Special Variant of smp_call_function for use by cache functions:
89  *
90  *  o No return value
91  *  o collapses to normal function call on UP kernels
92  *  o collapses to normal function call on systems with a single shared
93  *    primary cache.
94  *  o doesn't disable interrupts on the local CPU
95  */
96 static inline void r4k_on_each_cpu(unsigned int type,
97 				   void (*func)(void *info), void *info)
98 {
99 	preempt_disable();
100 	if (r4k_op_needs_ipi(type))
101 		smp_call_function_many(&cpu_foreign_map[smp_processor_id()],
102 				       func, info, 1);
103 	func(info);
104 	preempt_enable();
105 }
106 
107 /*
108  * Must die.
109  */
110 static unsigned long icache_size __read_mostly;
111 static unsigned long dcache_size __read_mostly;
112 static unsigned long vcache_size __read_mostly;
113 static unsigned long scache_size __read_mostly;
114 
115 /*
116  * Dummy cache handling routines for machines without boardcaches
117  */
118 static void cache_noop(void) {}
119 
120 static struct bcache_ops no_sc_ops = {
121 	.bc_enable = (void *)cache_noop,
122 	.bc_disable = (void *)cache_noop,
123 	.bc_wback_inv = (void *)cache_noop,
124 	.bc_inv = (void *)cache_noop
125 };
126 
127 struct bcache_ops *bcops = &no_sc_ops;
128 
129 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
130 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
131 
132 #define R4600_HIT_CACHEOP_WAR_IMPL					\
133 do {									\
134 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
135 		*(volatile unsigned long *)CKSEG1;			\
136 	if (R4600_V1_HIT_CACHEOP_WAR)					\
137 		__asm__ __volatile__("nop;nop;nop;nop");		\
138 } while (0)
139 
140 static void (*r4k_blast_dcache_page)(unsigned long addr);
141 
142 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
143 {
144 	R4600_HIT_CACHEOP_WAR_IMPL;
145 	blast_dcache32_page(addr);
146 }
147 
148 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
149 {
150 	blast_dcache64_page(addr);
151 }
152 
153 static inline void r4k_blast_dcache_page_dc128(unsigned long addr)
154 {
155 	blast_dcache128_page(addr);
156 }
157 
158 static void r4k_blast_dcache_page_setup(void)
159 {
160 	unsigned long  dc_lsize = cpu_dcache_line_size();
161 
162 	switch (dc_lsize) {
163 	case 0:
164 		r4k_blast_dcache_page = (void *)cache_noop;
165 		break;
166 	case 16:
167 		r4k_blast_dcache_page = blast_dcache16_page;
168 		break;
169 	case 32:
170 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
171 		break;
172 	case 64:
173 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
174 		break;
175 	case 128:
176 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc128;
177 		break;
178 	default:
179 		break;
180 	}
181 }
182 
183 #ifndef CONFIG_EVA
184 #define r4k_blast_dcache_user_page  r4k_blast_dcache_page
185 #else
186 
187 static void (*r4k_blast_dcache_user_page)(unsigned long addr);
188 
189 static void r4k_blast_dcache_user_page_setup(void)
190 {
191 	unsigned long  dc_lsize = cpu_dcache_line_size();
192 
193 	if (dc_lsize == 0)
194 		r4k_blast_dcache_user_page = (void *)cache_noop;
195 	else if (dc_lsize == 16)
196 		r4k_blast_dcache_user_page = blast_dcache16_user_page;
197 	else if (dc_lsize == 32)
198 		r4k_blast_dcache_user_page = blast_dcache32_user_page;
199 	else if (dc_lsize == 64)
200 		r4k_blast_dcache_user_page = blast_dcache64_user_page;
201 }
202 
203 #endif
204 
205 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
206 
207 static void r4k_blast_dcache_page_indexed_setup(void)
208 {
209 	unsigned long dc_lsize = cpu_dcache_line_size();
210 
211 	if (dc_lsize == 0)
212 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
213 	else if (dc_lsize == 16)
214 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
215 	else if (dc_lsize == 32)
216 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
217 	else if (dc_lsize == 64)
218 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
219 	else if (dc_lsize == 128)
220 		r4k_blast_dcache_page_indexed = blast_dcache128_page_indexed;
221 }
222 
223 void (* r4k_blast_dcache)(void);
224 EXPORT_SYMBOL(r4k_blast_dcache);
225 
226 static void r4k_blast_dcache_setup(void)
227 {
228 	unsigned long dc_lsize = cpu_dcache_line_size();
229 
230 	if (dc_lsize == 0)
231 		r4k_blast_dcache = (void *)cache_noop;
232 	else if (dc_lsize == 16)
233 		r4k_blast_dcache = blast_dcache16;
234 	else if (dc_lsize == 32)
235 		r4k_blast_dcache = blast_dcache32;
236 	else if (dc_lsize == 64)
237 		r4k_blast_dcache = blast_dcache64;
238 	else if (dc_lsize == 128)
239 		r4k_blast_dcache = blast_dcache128;
240 }
241 
242 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
243 #define JUMP_TO_ALIGN(order) \
244 	__asm__ __volatile__( \
245 		"b\t1f\n\t" \
246 		".align\t" #order "\n\t" \
247 		"1:\n\t" \
248 		)
249 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
250 #define CACHE32_UNROLL32_ALIGN2 JUMP_TO_ALIGN(11)
251 
252 static inline void blast_r4600_v1_icache32(void)
253 {
254 	unsigned long flags;
255 
256 	local_irq_save(flags);
257 	blast_icache32();
258 	local_irq_restore(flags);
259 }
260 
261 static inline void tx49_blast_icache32(void)
262 {
263 	unsigned long start = INDEX_BASE;
264 	unsigned long end = start + current_cpu_data.icache.waysize;
265 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
266 	unsigned long ws_end = current_cpu_data.icache.ways <<
267 			       current_cpu_data.icache.waybit;
268 	unsigned long ws, addr;
269 
270 	CACHE32_UNROLL32_ALIGN2;
271 	/* I'm in even chunk.  blast odd chunks */
272 	for (ws = 0; ws < ws_end; ws += ws_inc)
273 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
274 			cache32_unroll32(addr|ws, Index_Invalidate_I);
275 	CACHE32_UNROLL32_ALIGN;
276 	/* I'm in odd chunk.  blast even chunks */
277 	for (ws = 0; ws < ws_end; ws += ws_inc)
278 		for (addr = start; addr < end; addr += 0x400 * 2)
279 			cache32_unroll32(addr|ws, Index_Invalidate_I);
280 }
281 
282 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
283 {
284 	unsigned long flags;
285 
286 	local_irq_save(flags);
287 	blast_icache32_page_indexed(page);
288 	local_irq_restore(flags);
289 }
290 
291 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
292 {
293 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
294 	unsigned long start = INDEX_BASE + (page & indexmask);
295 	unsigned long end = start + PAGE_SIZE;
296 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
297 	unsigned long ws_end = current_cpu_data.icache.ways <<
298 			       current_cpu_data.icache.waybit;
299 	unsigned long ws, addr;
300 
301 	CACHE32_UNROLL32_ALIGN2;
302 	/* I'm in even chunk.  blast odd chunks */
303 	for (ws = 0; ws < ws_end; ws += ws_inc)
304 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
305 			cache32_unroll32(addr|ws, Index_Invalidate_I);
306 	CACHE32_UNROLL32_ALIGN;
307 	/* I'm in odd chunk.  blast even chunks */
308 	for (ws = 0; ws < ws_end; ws += ws_inc)
309 		for (addr = start; addr < end; addr += 0x400 * 2)
310 			cache32_unroll32(addr|ws, Index_Invalidate_I);
311 }
312 
313 static void (* r4k_blast_icache_page)(unsigned long addr);
314 
315 static void r4k_blast_icache_page_setup(void)
316 {
317 	unsigned long ic_lsize = cpu_icache_line_size();
318 
319 	if (ic_lsize == 0)
320 		r4k_blast_icache_page = (void *)cache_noop;
321 	else if (ic_lsize == 16)
322 		r4k_blast_icache_page = blast_icache16_page;
323 	else if (ic_lsize == 32 && current_cpu_type() == CPU_LOONGSON2)
324 		r4k_blast_icache_page = loongson2_blast_icache32_page;
325 	else if (ic_lsize == 32)
326 		r4k_blast_icache_page = blast_icache32_page;
327 	else if (ic_lsize == 64)
328 		r4k_blast_icache_page = blast_icache64_page;
329 	else if (ic_lsize == 128)
330 		r4k_blast_icache_page = blast_icache128_page;
331 }
332 
333 #ifndef CONFIG_EVA
334 #define r4k_blast_icache_user_page  r4k_blast_icache_page
335 #else
336 
337 static void (*r4k_blast_icache_user_page)(unsigned long addr);
338 
339 static void r4k_blast_icache_user_page_setup(void)
340 {
341 	unsigned long ic_lsize = cpu_icache_line_size();
342 
343 	if (ic_lsize == 0)
344 		r4k_blast_icache_user_page = (void *)cache_noop;
345 	else if (ic_lsize == 16)
346 		r4k_blast_icache_user_page = blast_icache16_user_page;
347 	else if (ic_lsize == 32)
348 		r4k_blast_icache_user_page = blast_icache32_user_page;
349 	else if (ic_lsize == 64)
350 		r4k_blast_icache_user_page = blast_icache64_user_page;
351 }
352 
353 #endif
354 
355 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
356 
357 static void r4k_blast_icache_page_indexed_setup(void)
358 {
359 	unsigned long ic_lsize = cpu_icache_line_size();
360 
361 	if (ic_lsize == 0)
362 		r4k_blast_icache_page_indexed = (void *)cache_noop;
363 	else if (ic_lsize == 16)
364 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
365 	else if (ic_lsize == 32) {
366 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
367 			r4k_blast_icache_page_indexed =
368 				blast_icache32_r4600_v1_page_indexed;
369 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
370 			r4k_blast_icache_page_indexed =
371 				tx49_blast_icache32_page_indexed;
372 		else if (current_cpu_type() == CPU_LOONGSON2)
373 			r4k_blast_icache_page_indexed =
374 				loongson2_blast_icache32_page_indexed;
375 		else
376 			r4k_blast_icache_page_indexed =
377 				blast_icache32_page_indexed;
378 	} else if (ic_lsize == 64)
379 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
380 }
381 
382 void (* r4k_blast_icache)(void);
383 EXPORT_SYMBOL(r4k_blast_icache);
384 
385 static void r4k_blast_icache_setup(void)
386 {
387 	unsigned long ic_lsize = cpu_icache_line_size();
388 
389 	if (ic_lsize == 0)
390 		r4k_blast_icache = (void *)cache_noop;
391 	else if (ic_lsize == 16)
392 		r4k_blast_icache = blast_icache16;
393 	else if (ic_lsize == 32) {
394 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
395 			r4k_blast_icache = blast_r4600_v1_icache32;
396 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
397 			r4k_blast_icache = tx49_blast_icache32;
398 		else if (current_cpu_type() == CPU_LOONGSON2)
399 			r4k_blast_icache = loongson2_blast_icache32;
400 		else
401 			r4k_blast_icache = blast_icache32;
402 	} else if (ic_lsize == 64)
403 		r4k_blast_icache = blast_icache64;
404 	else if (ic_lsize == 128)
405 		r4k_blast_icache = blast_icache128;
406 }
407 
408 static void (* r4k_blast_scache_page)(unsigned long addr);
409 
410 static void r4k_blast_scache_page_setup(void)
411 {
412 	unsigned long sc_lsize = cpu_scache_line_size();
413 
414 	if (scache_size == 0)
415 		r4k_blast_scache_page = (void *)cache_noop;
416 	else if (sc_lsize == 16)
417 		r4k_blast_scache_page = blast_scache16_page;
418 	else if (sc_lsize == 32)
419 		r4k_blast_scache_page = blast_scache32_page;
420 	else if (sc_lsize == 64)
421 		r4k_blast_scache_page = blast_scache64_page;
422 	else if (sc_lsize == 128)
423 		r4k_blast_scache_page = blast_scache128_page;
424 }
425 
426 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
427 
428 static void r4k_blast_scache_page_indexed_setup(void)
429 {
430 	unsigned long sc_lsize = cpu_scache_line_size();
431 
432 	if (scache_size == 0)
433 		r4k_blast_scache_page_indexed = (void *)cache_noop;
434 	else if (sc_lsize == 16)
435 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
436 	else if (sc_lsize == 32)
437 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
438 	else if (sc_lsize == 64)
439 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
440 	else if (sc_lsize == 128)
441 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
442 }
443 
444 static void (* r4k_blast_scache)(void);
445 
446 static void r4k_blast_scache_setup(void)
447 {
448 	unsigned long sc_lsize = cpu_scache_line_size();
449 
450 	if (scache_size == 0)
451 		r4k_blast_scache = (void *)cache_noop;
452 	else if (sc_lsize == 16)
453 		r4k_blast_scache = blast_scache16;
454 	else if (sc_lsize == 32)
455 		r4k_blast_scache = blast_scache32;
456 	else if (sc_lsize == 64)
457 		r4k_blast_scache = blast_scache64;
458 	else if (sc_lsize == 128)
459 		r4k_blast_scache = blast_scache128;
460 }
461 
462 static inline void local_r4k___flush_cache_all(void * args)
463 {
464 	switch (current_cpu_type()) {
465 	case CPU_LOONGSON2:
466 	case CPU_LOONGSON3:
467 	case CPU_R4000SC:
468 	case CPU_R4000MC:
469 	case CPU_R4400SC:
470 	case CPU_R4400MC:
471 	case CPU_R10000:
472 	case CPU_R12000:
473 	case CPU_R14000:
474 	case CPU_R16000:
475 		/*
476 		 * These caches are inclusive caches, that is, if something
477 		 * is not cached in the S-cache, we know it also won't be
478 		 * in one of the primary caches.
479 		 */
480 		r4k_blast_scache();
481 		break;
482 
483 	case CPU_BMIPS5000:
484 		r4k_blast_scache();
485 		__sync();
486 		break;
487 
488 	default:
489 		r4k_blast_dcache();
490 		r4k_blast_icache();
491 		break;
492 	}
493 }
494 
495 static void r4k___flush_cache_all(void)
496 {
497 	r4k_on_each_cpu(R4K_INDEX, local_r4k___flush_cache_all, NULL);
498 }
499 
500 /**
501  * has_valid_asid() - Determine if an mm already has an ASID.
502  * @mm:		Memory map.
503  * @type:	R4K_HIT or R4K_INDEX, type of cache op.
504  *
505  * Determines whether @mm already has an ASID on any of the CPUs which cache ops
506  * of type @type within an r4k_on_each_cpu() call will affect. If
507  * r4k_on_each_cpu() does an SMP call to a single VPE in each core, then the
508  * scope of the operation is confined to sibling CPUs, otherwise all online CPUs
509  * will need to be checked.
510  *
511  * Must be called in non-preemptive context.
512  *
513  * Returns:	1 if the CPUs affected by @type cache ops have an ASID for @mm.
514  *		0 otherwise.
515  */
516 static inline int has_valid_asid(const struct mm_struct *mm, unsigned int type)
517 {
518 	unsigned int i;
519 	const cpumask_t *mask = cpu_present_mask;
520 
521 	/* cpu_sibling_map[] undeclared when !CONFIG_SMP */
522 #ifdef CONFIG_SMP
523 	/*
524 	 * If r4k_on_each_cpu does SMP calls, it does them to a single VPE in
525 	 * each foreign core, so we only need to worry about siblings.
526 	 * Otherwise we need to worry about all present CPUs.
527 	 */
528 	if (r4k_op_needs_ipi(type))
529 		mask = &cpu_sibling_map[smp_processor_id()];
530 #endif
531 	for_each_cpu(i, mask)
532 		if (cpu_context(i, mm))
533 			return 1;
534 	return 0;
535 }
536 
537 static void r4k__flush_cache_vmap(void)
538 {
539 	r4k_blast_dcache();
540 }
541 
542 static void r4k__flush_cache_vunmap(void)
543 {
544 	r4k_blast_dcache();
545 }
546 
547 /*
548  * Note: flush_tlb_range() assumes flush_cache_range() sufficiently flushes
549  * whole caches when vma is executable.
550  */
551 static inline void local_r4k_flush_cache_range(void * args)
552 {
553 	struct vm_area_struct *vma = args;
554 	int exec = vma->vm_flags & VM_EXEC;
555 
556 	if (!has_valid_asid(vma->vm_mm, R4K_INDEX))
557 		return;
558 
559 	/*
560 	 * If dcache can alias, we must blast it since mapping is changing.
561 	 * If executable, we must ensure any dirty lines are written back far
562 	 * enough to be visible to icache.
563 	 */
564 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
565 		r4k_blast_dcache();
566 	/* If executable, blast stale lines from icache */
567 	if (exec)
568 		r4k_blast_icache();
569 }
570 
571 static void r4k_flush_cache_range(struct vm_area_struct *vma,
572 	unsigned long start, unsigned long end)
573 {
574 	int exec = vma->vm_flags & VM_EXEC;
575 
576 	if (cpu_has_dc_aliases || exec)
577 		r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_range, vma);
578 }
579 
580 static inline void local_r4k_flush_cache_mm(void * args)
581 {
582 	struct mm_struct *mm = args;
583 
584 	if (!has_valid_asid(mm, R4K_INDEX))
585 		return;
586 
587 	/*
588 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
589 	 * only flush the primary caches but R1x000 behave sane ...
590 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
591 	 * caches, so we can bail out early.
592 	 */
593 	if (current_cpu_type() == CPU_R4000SC ||
594 	    current_cpu_type() == CPU_R4000MC ||
595 	    current_cpu_type() == CPU_R4400SC ||
596 	    current_cpu_type() == CPU_R4400MC) {
597 		r4k_blast_scache();
598 		return;
599 	}
600 
601 	r4k_blast_dcache();
602 }
603 
604 static void r4k_flush_cache_mm(struct mm_struct *mm)
605 {
606 	if (!cpu_has_dc_aliases)
607 		return;
608 
609 	r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_mm, mm);
610 }
611 
612 struct flush_cache_page_args {
613 	struct vm_area_struct *vma;
614 	unsigned long addr;
615 	unsigned long pfn;
616 };
617 
618 static inline void local_r4k_flush_cache_page(void *args)
619 {
620 	struct flush_cache_page_args *fcp_args = args;
621 	struct vm_area_struct *vma = fcp_args->vma;
622 	unsigned long addr = fcp_args->addr;
623 	struct page *page = pfn_to_page(fcp_args->pfn);
624 	int exec = vma->vm_flags & VM_EXEC;
625 	struct mm_struct *mm = vma->vm_mm;
626 	int map_coherent = 0;
627 	pgd_t *pgdp;
628 	pud_t *pudp;
629 	pmd_t *pmdp;
630 	pte_t *ptep;
631 	void *vaddr;
632 
633 	/*
634 	 * If owns no valid ASID yet, cannot possibly have gotten
635 	 * this page into the cache.
636 	 */
637 	if (!has_valid_asid(mm, R4K_HIT))
638 		return;
639 
640 	addr &= PAGE_MASK;
641 	pgdp = pgd_offset(mm, addr);
642 	pudp = pud_offset(pgdp, addr);
643 	pmdp = pmd_offset(pudp, addr);
644 	ptep = pte_offset(pmdp, addr);
645 
646 	/*
647 	 * If the page isn't marked valid, the page cannot possibly be
648 	 * in the cache.
649 	 */
650 	if (!(pte_present(*ptep)))
651 		return;
652 
653 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
654 		vaddr = NULL;
655 	else {
656 		/*
657 		 * Use kmap_coherent or kmap_atomic to do flushes for
658 		 * another ASID than the current one.
659 		 */
660 		map_coherent = (cpu_has_dc_aliases &&
661 				page_mapcount(page) &&
662 				!Page_dcache_dirty(page));
663 		if (map_coherent)
664 			vaddr = kmap_coherent(page, addr);
665 		else
666 			vaddr = kmap_atomic(page);
667 		addr = (unsigned long)vaddr;
668 	}
669 
670 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
671 		vaddr ? r4k_blast_dcache_page(addr) :
672 			r4k_blast_dcache_user_page(addr);
673 		if (exec && !cpu_icache_snoops_remote_store)
674 			r4k_blast_scache_page(addr);
675 	}
676 	if (exec) {
677 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
678 			int cpu = smp_processor_id();
679 
680 			if (cpu_context(cpu, mm) != 0)
681 				drop_mmu_context(mm, cpu);
682 		} else
683 			vaddr ? r4k_blast_icache_page(addr) :
684 				r4k_blast_icache_user_page(addr);
685 	}
686 
687 	if (vaddr) {
688 		if (map_coherent)
689 			kunmap_coherent();
690 		else
691 			kunmap_atomic(vaddr);
692 	}
693 }
694 
695 static void r4k_flush_cache_page(struct vm_area_struct *vma,
696 	unsigned long addr, unsigned long pfn)
697 {
698 	struct flush_cache_page_args args;
699 
700 	args.vma = vma;
701 	args.addr = addr;
702 	args.pfn = pfn;
703 
704 	r4k_on_each_cpu(R4K_HIT, local_r4k_flush_cache_page, &args);
705 }
706 
707 static inline void local_r4k_flush_data_cache_page(void * addr)
708 {
709 	r4k_blast_dcache_page((unsigned long) addr);
710 }
711 
712 static void r4k_flush_data_cache_page(unsigned long addr)
713 {
714 	if (in_atomic())
715 		local_r4k_flush_data_cache_page((void *)addr);
716 	else
717 		r4k_on_each_cpu(R4K_HIT, local_r4k_flush_data_cache_page,
718 				(void *) addr);
719 }
720 
721 struct flush_icache_range_args {
722 	unsigned long start;
723 	unsigned long end;
724 	unsigned int type;
725 	bool user;
726 };
727 
728 static inline void __local_r4k_flush_icache_range(unsigned long start,
729 						  unsigned long end,
730 						  unsigned int type,
731 						  bool user)
732 {
733 	if (!cpu_has_ic_fills_f_dc) {
734 		if (type == R4K_INDEX ||
735 		    (type & R4K_INDEX && end - start >= dcache_size)) {
736 			r4k_blast_dcache();
737 		} else {
738 			R4600_HIT_CACHEOP_WAR_IMPL;
739 			if (user)
740 				protected_blast_dcache_range(start, end);
741 			else
742 				blast_dcache_range(start, end);
743 		}
744 	}
745 
746 	if (type == R4K_INDEX ||
747 	    (type & R4K_INDEX && end - start > icache_size))
748 		r4k_blast_icache();
749 	else {
750 		switch (boot_cpu_type()) {
751 		case CPU_LOONGSON2:
752 			protected_loongson2_blast_icache_range(start, end);
753 			break;
754 
755 		default:
756 			if (user)
757 				protected_blast_icache_range(start, end);
758 			else
759 				blast_icache_range(start, end);
760 			break;
761 		}
762 	}
763 }
764 
765 static inline void local_r4k_flush_icache_range(unsigned long start,
766 						unsigned long end)
767 {
768 	__local_r4k_flush_icache_range(start, end, R4K_HIT | R4K_INDEX, false);
769 }
770 
771 static inline void local_r4k_flush_icache_user_range(unsigned long start,
772 						     unsigned long end)
773 {
774 	__local_r4k_flush_icache_range(start, end, R4K_HIT | R4K_INDEX, true);
775 }
776 
777 static inline void local_r4k_flush_icache_range_ipi(void *args)
778 {
779 	struct flush_icache_range_args *fir_args = args;
780 	unsigned long start = fir_args->start;
781 	unsigned long end = fir_args->end;
782 	unsigned int type = fir_args->type;
783 	bool user = fir_args->user;
784 
785 	__local_r4k_flush_icache_range(start, end, type, user);
786 }
787 
788 static void __r4k_flush_icache_range(unsigned long start, unsigned long end,
789 				     bool user)
790 {
791 	struct flush_icache_range_args args;
792 	unsigned long size, cache_size;
793 
794 	args.start = start;
795 	args.end = end;
796 	args.type = R4K_HIT | R4K_INDEX;
797 	args.user = user;
798 
799 	/*
800 	 * Indexed cache ops require an SMP call.
801 	 * Consider if that can or should be avoided.
802 	 */
803 	preempt_disable();
804 	if (r4k_op_needs_ipi(R4K_INDEX) && !r4k_op_needs_ipi(R4K_HIT)) {
805 		/*
806 		 * If address-based cache ops don't require an SMP call, then
807 		 * use them exclusively for small flushes.
808 		 */
809 		size = end - start;
810 		cache_size = icache_size;
811 		if (!cpu_has_ic_fills_f_dc) {
812 			size *= 2;
813 			cache_size += dcache_size;
814 		}
815 		if (size <= cache_size)
816 			args.type &= ~R4K_INDEX;
817 	}
818 	r4k_on_each_cpu(args.type, local_r4k_flush_icache_range_ipi, &args);
819 	preempt_enable();
820 	instruction_hazard();
821 }
822 
823 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
824 {
825 	return __r4k_flush_icache_range(start, end, false);
826 }
827 
828 static void r4k_flush_icache_user_range(unsigned long start, unsigned long end)
829 {
830 	return __r4k_flush_icache_range(start, end, true);
831 }
832 
833 #ifdef CONFIG_DMA_NONCOHERENT
834 
835 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
836 {
837 	/* Catch bad driver code */
838 	if (WARN_ON(size == 0))
839 		return;
840 
841 	preempt_disable();
842 	if (cpu_has_inclusive_pcaches) {
843 		if (size >= scache_size)
844 			r4k_blast_scache();
845 		else
846 			blast_scache_range(addr, addr + size);
847 		preempt_enable();
848 		__sync();
849 		return;
850 	}
851 
852 	/*
853 	 * Either no secondary cache or the available caches don't have the
854 	 * subset property so we have to flush the primary caches
855 	 * explicitly.
856 	 * If we would need IPI to perform an INDEX-type operation, then
857 	 * we have to use the HIT-type alternative as IPI cannot be used
858 	 * here due to interrupts possibly being disabled.
859 	 */
860 	if (!r4k_op_needs_ipi(R4K_INDEX) && size >= dcache_size) {
861 		r4k_blast_dcache();
862 	} else {
863 		R4600_HIT_CACHEOP_WAR_IMPL;
864 		blast_dcache_range(addr, addr + size);
865 	}
866 	preempt_enable();
867 
868 	bc_wback_inv(addr, size);
869 	__sync();
870 }
871 
872 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
873 {
874 	/* Catch bad driver code */
875 	if (WARN_ON(size == 0))
876 		return;
877 
878 	preempt_disable();
879 	if (cpu_has_inclusive_pcaches) {
880 		if (size >= scache_size)
881 			r4k_blast_scache();
882 		else {
883 			/*
884 			 * There is no clearly documented alignment requirement
885 			 * for the cache instruction on MIPS processors and
886 			 * some processors, among them the RM5200 and RM7000
887 			 * QED processors will throw an address error for cache
888 			 * hit ops with insufficient alignment.	 Solved by
889 			 * aligning the address to cache line size.
890 			 */
891 			blast_inv_scache_range(addr, addr + size);
892 		}
893 		preempt_enable();
894 		__sync();
895 		return;
896 	}
897 
898 	if (!r4k_op_needs_ipi(R4K_INDEX) && size >= dcache_size) {
899 		r4k_blast_dcache();
900 	} else {
901 		R4600_HIT_CACHEOP_WAR_IMPL;
902 		blast_inv_dcache_range(addr, addr + size);
903 	}
904 	preempt_enable();
905 
906 	bc_inv(addr, size);
907 	__sync();
908 }
909 #endif /* CONFIG_DMA_NONCOHERENT */
910 
911 struct flush_cache_sigtramp_args {
912 	struct mm_struct *mm;
913 	struct page *page;
914 	unsigned long addr;
915 };
916 
917 /*
918  * While we're protected against bad userland addresses we don't care
919  * very much about what happens in that case.  Usually a segmentation
920  * fault will dump the process later on anyway ...
921  */
922 static void local_r4k_flush_cache_sigtramp(void *args)
923 {
924 	struct flush_cache_sigtramp_args *fcs_args = args;
925 	unsigned long addr = fcs_args->addr;
926 	struct page *page = fcs_args->page;
927 	struct mm_struct *mm = fcs_args->mm;
928 	int map_coherent = 0;
929 	void *vaddr;
930 
931 	unsigned long ic_lsize = cpu_icache_line_size();
932 	unsigned long dc_lsize = cpu_dcache_line_size();
933 	unsigned long sc_lsize = cpu_scache_line_size();
934 
935 	/*
936 	 * If owns no valid ASID yet, cannot possibly have gotten
937 	 * this page into the cache.
938 	 */
939 	if (!has_valid_asid(mm, R4K_HIT))
940 		return;
941 
942 	if (mm == current->active_mm) {
943 		vaddr = NULL;
944 	} else {
945 		/*
946 		 * Use kmap_coherent or kmap_atomic to do flushes for
947 		 * another ASID than the current one.
948 		 */
949 		map_coherent = (cpu_has_dc_aliases &&
950 				page_mapcount(page) &&
951 				!Page_dcache_dirty(page));
952 		if (map_coherent)
953 			vaddr = kmap_coherent(page, addr);
954 		else
955 			vaddr = kmap_atomic(page);
956 		addr = (unsigned long)vaddr + (addr & ~PAGE_MASK);
957 	}
958 
959 	R4600_HIT_CACHEOP_WAR_IMPL;
960 	if (!cpu_has_ic_fills_f_dc) {
961 		if (dc_lsize)
962 			vaddr ? flush_dcache_line(addr & ~(dc_lsize - 1))
963 			      : protected_writeback_dcache_line(
964 							addr & ~(dc_lsize - 1));
965 		if (!cpu_icache_snoops_remote_store && scache_size)
966 			vaddr ? flush_scache_line(addr & ~(sc_lsize - 1))
967 			      : protected_writeback_scache_line(
968 							addr & ~(sc_lsize - 1));
969 	}
970 	if (ic_lsize)
971 		vaddr ? flush_icache_line(addr & ~(ic_lsize - 1))
972 		      : protected_flush_icache_line(addr & ~(ic_lsize - 1));
973 
974 	if (vaddr) {
975 		if (map_coherent)
976 			kunmap_coherent();
977 		else
978 			kunmap_atomic(vaddr);
979 	}
980 
981 	if (MIPS4K_ICACHE_REFILL_WAR) {
982 		__asm__ __volatile__ (
983 			".set push\n\t"
984 			".set noat\n\t"
985 			".set "MIPS_ISA_LEVEL"\n\t"
986 #ifdef CONFIG_32BIT
987 			"la	$at,1f\n\t"
988 #endif
989 #ifdef CONFIG_64BIT
990 			"dla	$at,1f\n\t"
991 #endif
992 			"cache	%0,($at)\n\t"
993 			"nop; nop; nop\n"
994 			"1:\n\t"
995 			".set pop"
996 			:
997 			: "i" (Hit_Invalidate_I));
998 	}
999 	if (MIPS_CACHE_SYNC_WAR)
1000 		__asm__ __volatile__ ("sync");
1001 }
1002 
1003 static void r4k_flush_cache_sigtramp(unsigned long addr)
1004 {
1005 	struct flush_cache_sigtramp_args args;
1006 	int npages;
1007 
1008 	down_read(&current->mm->mmap_sem);
1009 
1010 	npages = get_user_pages_fast(addr, 1, 0, &args.page);
1011 	if (npages < 1)
1012 		goto out;
1013 
1014 	args.mm = current->mm;
1015 	args.addr = addr;
1016 
1017 	r4k_on_each_cpu(R4K_HIT, local_r4k_flush_cache_sigtramp, &args);
1018 
1019 	put_page(args.page);
1020 out:
1021 	up_read(&current->mm->mmap_sem);
1022 }
1023 
1024 static void r4k_flush_icache_all(void)
1025 {
1026 	if (cpu_has_vtag_icache)
1027 		r4k_blast_icache();
1028 }
1029 
1030 struct flush_kernel_vmap_range_args {
1031 	unsigned long	vaddr;
1032 	int		size;
1033 };
1034 
1035 static inline void local_r4k_flush_kernel_vmap_range_index(void *args)
1036 {
1037 	/*
1038 	 * Aliases only affect the primary caches so don't bother with
1039 	 * S-caches or T-caches.
1040 	 */
1041 	r4k_blast_dcache();
1042 }
1043 
1044 static inline void local_r4k_flush_kernel_vmap_range(void *args)
1045 {
1046 	struct flush_kernel_vmap_range_args *vmra = args;
1047 	unsigned long vaddr = vmra->vaddr;
1048 	int size = vmra->size;
1049 
1050 	/*
1051 	 * Aliases only affect the primary caches so don't bother with
1052 	 * S-caches or T-caches.
1053 	 */
1054 	R4600_HIT_CACHEOP_WAR_IMPL;
1055 	blast_dcache_range(vaddr, vaddr + size);
1056 }
1057 
1058 static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
1059 {
1060 	struct flush_kernel_vmap_range_args args;
1061 
1062 	args.vaddr = (unsigned long) vaddr;
1063 	args.size = size;
1064 
1065 	if (size >= dcache_size)
1066 		r4k_on_each_cpu(R4K_INDEX,
1067 				local_r4k_flush_kernel_vmap_range_index, NULL);
1068 	else
1069 		r4k_on_each_cpu(R4K_HIT, local_r4k_flush_kernel_vmap_range,
1070 				&args);
1071 }
1072 
1073 static inline void rm7k_erratum31(void)
1074 {
1075 	const unsigned long ic_lsize = 32;
1076 	unsigned long addr;
1077 
1078 	/* RM7000 erratum #31. The icache is screwed at startup. */
1079 	write_c0_taglo(0);
1080 	write_c0_taghi(0);
1081 
1082 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
1083 		__asm__ __volatile__ (
1084 			".set push\n\t"
1085 			".set noreorder\n\t"
1086 			".set mips3\n\t"
1087 			"cache\t%1, 0(%0)\n\t"
1088 			"cache\t%1, 0x1000(%0)\n\t"
1089 			"cache\t%1, 0x2000(%0)\n\t"
1090 			"cache\t%1, 0x3000(%0)\n\t"
1091 			"cache\t%2, 0(%0)\n\t"
1092 			"cache\t%2, 0x1000(%0)\n\t"
1093 			"cache\t%2, 0x2000(%0)\n\t"
1094 			"cache\t%2, 0x3000(%0)\n\t"
1095 			"cache\t%1, 0(%0)\n\t"
1096 			"cache\t%1, 0x1000(%0)\n\t"
1097 			"cache\t%1, 0x2000(%0)\n\t"
1098 			"cache\t%1, 0x3000(%0)\n\t"
1099 			".set pop\n"
1100 			:
1101 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
1102 	}
1103 }
1104 
1105 static inline int alias_74k_erratum(struct cpuinfo_mips *c)
1106 {
1107 	unsigned int imp = c->processor_id & PRID_IMP_MASK;
1108 	unsigned int rev = c->processor_id & PRID_REV_MASK;
1109 	int present = 0;
1110 
1111 	/*
1112 	 * Early versions of the 74K do not update the cache tags on a
1113 	 * vtag miss/ptag hit which can occur in the case of KSEG0/KUSEG
1114 	 * aliases.  In this case it is better to treat the cache as always
1115 	 * having aliases.  Also disable the synonym tag update feature
1116 	 * where available.  In this case no opportunistic tag update will
1117 	 * happen where a load causes a virtual address miss but a physical
1118 	 * address hit during a D-cache look-up.
1119 	 */
1120 	switch (imp) {
1121 	case PRID_IMP_74K:
1122 		if (rev <= PRID_REV_ENCODE_332(2, 4, 0))
1123 			present = 1;
1124 		if (rev == PRID_REV_ENCODE_332(2, 4, 0))
1125 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
1126 		break;
1127 	case PRID_IMP_1074K:
1128 		if (rev <= PRID_REV_ENCODE_332(1, 1, 0)) {
1129 			present = 1;
1130 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
1131 		}
1132 		break;
1133 	default:
1134 		BUG();
1135 	}
1136 
1137 	return present;
1138 }
1139 
1140 static void b5k_instruction_hazard(void)
1141 {
1142 	__sync();
1143 	__sync();
1144 	__asm__ __volatile__(
1145 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1146 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1147 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1148 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1149 	: : : "memory");
1150 }
1151 
1152 static char *way_string[] = { NULL, "direct mapped", "2-way",
1153 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way",
1154 	"9-way", "10-way", "11-way", "12-way",
1155 	"13-way", "14-way", "15-way", "16-way",
1156 };
1157 
1158 static void probe_pcache(void)
1159 {
1160 	struct cpuinfo_mips *c = &current_cpu_data;
1161 	unsigned int config = read_c0_config();
1162 	unsigned int prid = read_c0_prid();
1163 	int has_74k_erratum = 0;
1164 	unsigned long config1;
1165 	unsigned int lsize;
1166 
1167 	switch (current_cpu_type()) {
1168 	case CPU_R4600:			/* QED style two way caches? */
1169 	case CPU_R4700:
1170 	case CPU_R5000:
1171 	case CPU_NEVADA:
1172 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1173 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1174 		c->icache.ways = 2;
1175 		c->icache.waybit = __ffs(icache_size/2);
1176 
1177 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1178 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1179 		c->dcache.ways = 2;
1180 		c->dcache.waybit= __ffs(dcache_size/2);
1181 
1182 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1183 		break;
1184 
1185 	case CPU_R5432:
1186 	case CPU_R5500:
1187 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1188 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1189 		c->icache.ways = 2;
1190 		c->icache.waybit= 0;
1191 
1192 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1193 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1194 		c->dcache.ways = 2;
1195 		c->dcache.waybit = 0;
1196 
1197 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
1198 		break;
1199 
1200 	case CPU_TX49XX:
1201 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1202 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1203 		c->icache.ways = 4;
1204 		c->icache.waybit= 0;
1205 
1206 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1207 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1208 		c->dcache.ways = 4;
1209 		c->dcache.waybit = 0;
1210 
1211 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1212 		c->options |= MIPS_CPU_PREFETCH;
1213 		break;
1214 
1215 	case CPU_R4000PC:
1216 	case CPU_R4000SC:
1217 	case CPU_R4000MC:
1218 	case CPU_R4400PC:
1219 	case CPU_R4400SC:
1220 	case CPU_R4400MC:
1221 	case CPU_R4300:
1222 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1223 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1224 		c->icache.ways = 1;
1225 		c->icache.waybit = 0;	/* doesn't matter */
1226 
1227 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1228 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1229 		c->dcache.ways = 1;
1230 		c->dcache.waybit = 0;	/* does not matter */
1231 
1232 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1233 		break;
1234 
1235 	case CPU_R10000:
1236 	case CPU_R12000:
1237 	case CPU_R14000:
1238 	case CPU_R16000:
1239 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
1240 		c->icache.linesz = 64;
1241 		c->icache.ways = 2;
1242 		c->icache.waybit = 0;
1243 
1244 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
1245 		c->dcache.linesz = 32;
1246 		c->dcache.ways = 2;
1247 		c->dcache.waybit = 0;
1248 
1249 		c->options |= MIPS_CPU_PREFETCH;
1250 		break;
1251 
1252 	case CPU_VR4133:
1253 		write_c0_config(config & ~VR41_CONF_P4K);
1254 	case CPU_VR4131:
1255 		/* Workaround for cache instruction bug of VR4131 */
1256 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
1257 		    c->processor_id == 0x0c82U) {
1258 			config |= 0x00400000U;
1259 			if (c->processor_id == 0x0c80U)
1260 				config |= VR41_CONF_BP;
1261 			write_c0_config(config);
1262 		} else
1263 			c->options |= MIPS_CPU_CACHE_CDEX_P;
1264 
1265 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
1266 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1267 		c->icache.ways = 2;
1268 		c->icache.waybit = __ffs(icache_size/2);
1269 
1270 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
1271 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1272 		c->dcache.ways = 2;
1273 		c->dcache.waybit = __ffs(dcache_size/2);
1274 		break;
1275 
1276 	case CPU_VR41XX:
1277 	case CPU_VR4111:
1278 	case CPU_VR4121:
1279 	case CPU_VR4122:
1280 	case CPU_VR4181:
1281 	case CPU_VR4181A:
1282 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
1283 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1284 		c->icache.ways = 1;
1285 		c->icache.waybit = 0;	/* doesn't matter */
1286 
1287 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
1288 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1289 		c->dcache.ways = 1;
1290 		c->dcache.waybit = 0;	/* does not matter */
1291 
1292 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1293 		break;
1294 
1295 	case CPU_RM7000:
1296 		rm7k_erratum31();
1297 
1298 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1299 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1300 		c->icache.ways = 4;
1301 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
1302 
1303 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1304 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1305 		c->dcache.ways = 4;
1306 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
1307 
1308 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1309 		c->options |= MIPS_CPU_PREFETCH;
1310 		break;
1311 
1312 	case CPU_LOONGSON2:
1313 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1314 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1315 		if (prid & 0x3)
1316 			c->icache.ways = 4;
1317 		else
1318 			c->icache.ways = 2;
1319 		c->icache.waybit = 0;
1320 
1321 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1322 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1323 		if (prid & 0x3)
1324 			c->dcache.ways = 4;
1325 		else
1326 			c->dcache.ways = 2;
1327 		c->dcache.waybit = 0;
1328 		break;
1329 
1330 	case CPU_LOONGSON3:
1331 		config1 = read_c0_config1();
1332 		lsize = (config1 >> 19) & 7;
1333 		if (lsize)
1334 			c->icache.linesz = 2 << lsize;
1335 		else
1336 			c->icache.linesz = 0;
1337 		c->icache.sets = 64 << ((config1 >> 22) & 7);
1338 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1339 		icache_size = c->icache.sets *
1340 					  c->icache.ways *
1341 					  c->icache.linesz;
1342 		c->icache.waybit = 0;
1343 
1344 		lsize = (config1 >> 10) & 7;
1345 		if (lsize)
1346 			c->dcache.linesz = 2 << lsize;
1347 		else
1348 			c->dcache.linesz = 0;
1349 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
1350 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1351 		dcache_size = c->dcache.sets *
1352 					  c->dcache.ways *
1353 					  c->dcache.linesz;
1354 		c->dcache.waybit = 0;
1355 		if ((prid & PRID_REV_MASK) >= PRID_REV_LOONGSON3A_R2)
1356 			c->options |= MIPS_CPU_PREFETCH;
1357 		break;
1358 
1359 	case CPU_CAVIUM_OCTEON3:
1360 		/* For now lie about the number of ways. */
1361 		c->icache.linesz = 128;
1362 		c->icache.sets = 16;
1363 		c->icache.ways = 8;
1364 		c->icache.flags |= MIPS_CACHE_VTAG;
1365 		icache_size = c->icache.sets * c->icache.ways * c->icache.linesz;
1366 
1367 		c->dcache.linesz = 128;
1368 		c->dcache.ways = 8;
1369 		c->dcache.sets = 8;
1370 		dcache_size = c->dcache.sets * c->dcache.ways * c->dcache.linesz;
1371 		c->options |= MIPS_CPU_PREFETCH;
1372 		break;
1373 
1374 	default:
1375 		if (!(config & MIPS_CONF_M))
1376 			panic("Don't know how to probe P-caches on this cpu.");
1377 
1378 		/*
1379 		 * So we seem to be a MIPS32 or MIPS64 CPU
1380 		 * So let's probe the I-cache ...
1381 		 */
1382 		config1 = read_c0_config1();
1383 
1384 		lsize = (config1 >> 19) & 7;
1385 
1386 		/* IL == 7 is reserved */
1387 		if (lsize == 7)
1388 			panic("Invalid icache line size");
1389 
1390 		c->icache.linesz = lsize ? 2 << lsize : 0;
1391 
1392 		c->icache.sets = 32 << (((config1 >> 22) + 1) & 7);
1393 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1394 
1395 		icache_size = c->icache.sets *
1396 			      c->icache.ways *
1397 			      c->icache.linesz;
1398 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
1399 
1400 		if (config & MIPS_CONF_VI)
1401 			c->icache.flags |= MIPS_CACHE_VTAG;
1402 
1403 		/*
1404 		 * Now probe the MIPS32 / MIPS64 data cache.
1405 		 */
1406 		c->dcache.flags = 0;
1407 
1408 		lsize = (config1 >> 10) & 7;
1409 
1410 		/* DL == 7 is reserved */
1411 		if (lsize == 7)
1412 			panic("Invalid dcache line size");
1413 
1414 		c->dcache.linesz = lsize ? 2 << lsize : 0;
1415 
1416 		c->dcache.sets = 32 << (((config1 >> 13) + 1) & 7);
1417 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1418 
1419 		dcache_size = c->dcache.sets *
1420 			      c->dcache.ways *
1421 			      c->dcache.linesz;
1422 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
1423 
1424 		c->options |= MIPS_CPU_PREFETCH;
1425 		break;
1426 	}
1427 
1428 	/*
1429 	 * Processor configuration sanity check for the R4000SC erratum
1430 	 * #5.	With page sizes larger than 32kB there is no possibility
1431 	 * to get a VCE exception anymore so we don't care about this
1432 	 * misconfiguration.  The case is rather theoretical anyway;
1433 	 * presumably no vendor is shipping his hardware in the "bad"
1434 	 * configuration.
1435 	 */
1436 	if ((prid & PRID_IMP_MASK) == PRID_IMP_R4000 &&
1437 	    (prid & PRID_REV_MASK) < PRID_REV_R4400 &&
1438 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
1439 	    PAGE_SIZE <= 0x8000)
1440 		panic("Improper R4000SC processor configuration detected");
1441 
1442 	/* compute a couple of other cache variables */
1443 	c->icache.waysize = icache_size / c->icache.ways;
1444 	c->dcache.waysize = dcache_size / c->dcache.ways;
1445 
1446 	c->icache.sets = c->icache.linesz ?
1447 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
1448 	c->dcache.sets = c->dcache.linesz ?
1449 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
1450 
1451 	/*
1452 	 * R1x000 P-caches are odd in a positive way.  They're 32kB 2-way
1453 	 * virtually indexed so normally would suffer from aliases.  So
1454 	 * normally they'd suffer from aliases but magic in the hardware deals
1455 	 * with that for us so we don't need to take care ourselves.
1456 	 */
1457 	switch (current_cpu_type()) {
1458 	case CPU_20KC:
1459 	case CPU_25KF:
1460 	case CPU_I6400:
1461 	case CPU_I6500:
1462 	case CPU_SB1:
1463 	case CPU_SB1A:
1464 	case CPU_XLR:
1465 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1466 		break;
1467 
1468 	case CPU_R10000:
1469 	case CPU_R12000:
1470 	case CPU_R14000:
1471 	case CPU_R16000:
1472 		break;
1473 
1474 	case CPU_74K:
1475 	case CPU_1074K:
1476 		has_74k_erratum = alias_74k_erratum(c);
1477 		/* Fall through. */
1478 	case CPU_M14KC:
1479 	case CPU_M14KEC:
1480 	case CPU_24K:
1481 	case CPU_34K:
1482 	case CPU_1004K:
1483 	case CPU_INTERAPTIV:
1484 	case CPU_P5600:
1485 	case CPU_PROAPTIV:
1486 	case CPU_M5150:
1487 	case CPU_QEMU_GENERIC:
1488 	case CPU_P6600:
1489 	case CPU_M6250:
1490 		if (!(read_c0_config7() & MIPS_CONF7_IAR) &&
1491 		    (c->icache.waysize > PAGE_SIZE))
1492 			c->icache.flags |= MIPS_CACHE_ALIASES;
1493 		if (!has_74k_erratum && (read_c0_config7() & MIPS_CONF7_AR)) {
1494 			/*
1495 			 * Effectively physically indexed dcache,
1496 			 * thus no virtual aliases.
1497 			*/
1498 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1499 			break;
1500 		}
1501 	default:
1502 		if (has_74k_erratum || c->dcache.waysize > PAGE_SIZE)
1503 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1504 	}
1505 
1506 	/* Physically indexed caches don't suffer from virtual aliasing */
1507 	if (c->dcache.flags & MIPS_CACHE_PINDEX)
1508 		c->dcache.flags &= ~MIPS_CACHE_ALIASES;
1509 
1510 	/*
1511 	 * In systems with CM the icache fills from L2 or closer caches, and
1512 	 * thus sees remote stores without needing to write them back any
1513 	 * further than that.
1514 	 */
1515 	if (mips_cm_present())
1516 		c->icache.flags |= MIPS_IC_SNOOPS_REMOTE;
1517 
1518 	switch (current_cpu_type()) {
1519 	case CPU_20KC:
1520 		/*
1521 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1522 		 * the config register.
1523 		 */
1524 		c->icache.flags |= MIPS_CACHE_VTAG;
1525 		break;
1526 
1527 	case CPU_ALCHEMY:
1528 	case CPU_I6400:
1529 	case CPU_I6500:
1530 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1531 		break;
1532 
1533 	case CPU_BMIPS5000:
1534 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1535 		/* Cache aliases are handled in hardware; allow HIGHMEM */
1536 		c->dcache.flags &= ~MIPS_CACHE_ALIASES;
1537 		break;
1538 
1539 	case CPU_LOONGSON2:
1540 		/*
1541 		 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1542 		 * one op will act on all 4 ways
1543 		 */
1544 		c->icache.ways = 1;
1545 	}
1546 
1547 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1548 	       icache_size >> 10,
1549 	       c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1550 	       way_string[c->icache.ways], c->icache.linesz);
1551 
1552 	printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1553 	       dcache_size >> 10, way_string[c->dcache.ways],
1554 	       (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1555 	       (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1556 			"cache aliases" : "no aliases",
1557 	       c->dcache.linesz);
1558 }
1559 
1560 static void probe_vcache(void)
1561 {
1562 	struct cpuinfo_mips *c = &current_cpu_data;
1563 	unsigned int config2, lsize;
1564 
1565 	if (current_cpu_type() != CPU_LOONGSON3)
1566 		return;
1567 
1568 	config2 = read_c0_config2();
1569 	if ((lsize = ((config2 >> 20) & 15)))
1570 		c->vcache.linesz = 2 << lsize;
1571 	else
1572 		c->vcache.linesz = lsize;
1573 
1574 	c->vcache.sets = 64 << ((config2 >> 24) & 15);
1575 	c->vcache.ways = 1 + ((config2 >> 16) & 15);
1576 
1577 	vcache_size = c->vcache.sets * c->vcache.ways * c->vcache.linesz;
1578 
1579 	c->vcache.waybit = 0;
1580 	c->vcache.waysize = vcache_size / c->vcache.ways;
1581 
1582 	pr_info("Unified victim cache %ldkB %s, linesize %d bytes.\n",
1583 		vcache_size >> 10, way_string[c->vcache.ways], c->vcache.linesz);
1584 }
1585 
1586 /*
1587  * If you even _breathe_ on this function, look at the gcc output and make sure
1588  * it does not pop things on and off the stack for the cache sizing loop that
1589  * executes in KSEG1 space or else you will crash and burn badly.  You have
1590  * been warned.
1591  */
1592 static int probe_scache(void)
1593 {
1594 	unsigned long flags, addr, begin, end, pow2;
1595 	unsigned int config = read_c0_config();
1596 	struct cpuinfo_mips *c = &current_cpu_data;
1597 
1598 	if (config & CONF_SC)
1599 		return 0;
1600 
1601 	begin = (unsigned long) &_stext;
1602 	begin &= ~((4 * 1024 * 1024) - 1);
1603 	end = begin + (4 * 1024 * 1024);
1604 
1605 	/*
1606 	 * This is such a bitch, you'd think they would make it easy to do
1607 	 * this.  Away you daemons of stupidity!
1608 	 */
1609 	local_irq_save(flags);
1610 
1611 	/* Fill each size-multiple cache line with a valid tag. */
1612 	pow2 = (64 * 1024);
1613 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1614 		unsigned long *p = (unsigned long *) addr;
1615 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1616 		pow2 <<= 1;
1617 	}
1618 
1619 	/* Load first line with zero (therefore invalid) tag. */
1620 	write_c0_taglo(0);
1621 	write_c0_taghi(0);
1622 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1623 	cache_op(Index_Store_Tag_I, begin);
1624 	cache_op(Index_Store_Tag_D, begin);
1625 	cache_op(Index_Store_Tag_SD, begin);
1626 
1627 	/* Now search for the wrap around point. */
1628 	pow2 = (128 * 1024);
1629 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1630 		cache_op(Index_Load_Tag_SD, addr);
1631 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1632 		if (!read_c0_taglo())
1633 			break;
1634 		pow2 <<= 1;
1635 	}
1636 	local_irq_restore(flags);
1637 	addr -= begin;
1638 
1639 	scache_size = addr;
1640 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1641 	c->scache.ways = 1;
1642 	c->scache.waybit = 0;		/* does not matter */
1643 
1644 	return 1;
1645 }
1646 
1647 static void __init loongson2_sc_init(void)
1648 {
1649 	struct cpuinfo_mips *c = &current_cpu_data;
1650 
1651 	scache_size = 512*1024;
1652 	c->scache.linesz = 32;
1653 	c->scache.ways = 4;
1654 	c->scache.waybit = 0;
1655 	c->scache.waysize = scache_size / (c->scache.ways);
1656 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1657 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1658 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1659 
1660 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1661 }
1662 
1663 static void __init loongson3_sc_init(void)
1664 {
1665 	struct cpuinfo_mips *c = &current_cpu_data;
1666 	unsigned int config2, lsize;
1667 
1668 	config2 = read_c0_config2();
1669 	lsize = (config2 >> 4) & 15;
1670 	if (lsize)
1671 		c->scache.linesz = 2 << lsize;
1672 	else
1673 		c->scache.linesz = 0;
1674 	c->scache.sets = 64 << ((config2 >> 8) & 15);
1675 	c->scache.ways = 1 + (config2 & 15);
1676 
1677 	scache_size = c->scache.sets *
1678 				  c->scache.ways *
1679 				  c->scache.linesz;
1680 	/* Loongson-3 has 4 cores, 1MB scache for each. scaches are shared */
1681 	scache_size *= 4;
1682 	c->scache.waybit = 0;
1683 	c->scache.waysize = scache_size / c->scache.ways;
1684 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1685 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1686 	if (scache_size)
1687 		c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1688 	return;
1689 }
1690 
1691 extern int r5k_sc_init(void);
1692 extern int rm7k_sc_init(void);
1693 extern int mips_sc_init(void);
1694 
1695 static void setup_scache(void)
1696 {
1697 	struct cpuinfo_mips *c = &current_cpu_data;
1698 	unsigned int config = read_c0_config();
1699 	int sc_present = 0;
1700 
1701 	/*
1702 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1703 	 * processors don't have a S-cache that would be relevant to the
1704 	 * Linux memory management.
1705 	 */
1706 	switch (current_cpu_type()) {
1707 	case CPU_R4000SC:
1708 	case CPU_R4000MC:
1709 	case CPU_R4400SC:
1710 	case CPU_R4400MC:
1711 		sc_present = run_uncached(probe_scache);
1712 		if (sc_present)
1713 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1714 		break;
1715 
1716 	case CPU_R10000:
1717 	case CPU_R12000:
1718 	case CPU_R14000:
1719 	case CPU_R16000:
1720 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1721 		c->scache.linesz = 64 << ((config >> 13) & 1);
1722 		c->scache.ways = 2;
1723 		c->scache.waybit= 0;
1724 		sc_present = 1;
1725 		break;
1726 
1727 	case CPU_R5000:
1728 	case CPU_NEVADA:
1729 #ifdef CONFIG_R5000_CPU_SCACHE
1730 		r5k_sc_init();
1731 #endif
1732 		return;
1733 
1734 	case CPU_RM7000:
1735 #ifdef CONFIG_RM7000_CPU_SCACHE
1736 		rm7k_sc_init();
1737 #endif
1738 		return;
1739 
1740 	case CPU_LOONGSON2:
1741 		loongson2_sc_init();
1742 		return;
1743 
1744 	case CPU_LOONGSON3:
1745 		loongson3_sc_init();
1746 		return;
1747 
1748 	case CPU_CAVIUM_OCTEON3:
1749 	case CPU_XLP:
1750 		/* don't need to worry about L2, fully coherent */
1751 		return;
1752 
1753 	default:
1754 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M32R2 |
1755 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R1 |
1756 				    MIPS_CPU_ISA_M64R2 | MIPS_CPU_ISA_M64R6)) {
1757 #ifdef CONFIG_MIPS_CPU_SCACHE
1758 			if (mips_sc_init ()) {
1759 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1760 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1761 				       scache_size >> 10,
1762 				       way_string[c->scache.ways], c->scache.linesz);
1763 			}
1764 #else
1765 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1766 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1767 #endif
1768 			return;
1769 		}
1770 		sc_present = 0;
1771 	}
1772 
1773 	if (!sc_present)
1774 		return;
1775 
1776 	/* compute a couple of other cache variables */
1777 	c->scache.waysize = scache_size / c->scache.ways;
1778 
1779 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1780 
1781 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1782 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1783 
1784 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1785 }
1786 
1787 void au1x00_fixup_config_od(void)
1788 {
1789 	/*
1790 	 * c0_config.od (bit 19) was write only (and read as 0)
1791 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1792 	 * transaction overlapping and needs to be set to fix various errata.
1793 	 */
1794 	switch (read_c0_prid()) {
1795 	case 0x00030100: /* Au1000 DA */
1796 	case 0x00030201: /* Au1000 HA */
1797 	case 0x00030202: /* Au1000 HB */
1798 	case 0x01030200: /* Au1500 AB */
1799 	/*
1800 	 * Au1100 errata actually keeps silence about this bit, so we set it
1801 	 * just in case for those revisions that require it to be set according
1802 	 * to the (now gone) cpu table.
1803 	 */
1804 	case 0x02030200: /* Au1100 AB */
1805 	case 0x02030201: /* Au1100 BA */
1806 	case 0x02030202: /* Au1100 BC */
1807 		set_c0_config(1 << 19);
1808 		break;
1809 	}
1810 }
1811 
1812 /* CP0 hazard avoidance. */
1813 #define NXP_BARRIER()							\
1814 	 __asm__ __volatile__(						\
1815 	".set noreorder\n\t"						\
1816 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1817 	".set reorder\n\t")
1818 
1819 static void nxp_pr4450_fixup_config(void)
1820 {
1821 	unsigned long config0;
1822 
1823 	config0 = read_c0_config();
1824 
1825 	/* clear all three cache coherency fields */
1826 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1827 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1828 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1829 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1830 	write_c0_config(config0);
1831 	NXP_BARRIER();
1832 }
1833 
1834 static int cca = -1;
1835 
1836 static int __init cca_setup(char *str)
1837 {
1838 	get_option(&str, &cca);
1839 
1840 	return 0;
1841 }
1842 
1843 early_param("cca", cca_setup);
1844 
1845 static void coherency_setup(void)
1846 {
1847 	if (cca < 0 || cca > 7)
1848 		cca = read_c0_config() & CONF_CM_CMASK;
1849 	_page_cachable_default = cca << _CACHE_SHIFT;
1850 
1851 	pr_debug("Using cache attribute %d\n", cca);
1852 	change_c0_config(CONF_CM_CMASK, cca);
1853 
1854 	/*
1855 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1856 	 * the coherency mode specified by the TLB; 1 means cachable
1857 	 * coherent update on write will be used.  Not all processors have
1858 	 * this bit and; some wire it to zero, others like Toshiba had the
1859 	 * silly idea of putting something else there ...
1860 	 */
1861 	switch (current_cpu_type()) {
1862 	case CPU_R4000PC:
1863 	case CPU_R4000SC:
1864 	case CPU_R4000MC:
1865 	case CPU_R4400PC:
1866 	case CPU_R4400SC:
1867 	case CPU_R4400MC:
1868 		clear_c0_config(CONF_CU);
1869 		break;
1870 	/*
1871 	 * We need to catch the early Alchemy SOCs with
1872 	 * the write-only co_config.od bit and set it back to one on:
1873 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1874 	 */
1875 	case CPU_ALCHEMY:
1876 		au1x00_fixup_config_od();
1877 		break;
1878 
1879 	case PRID_IMP_PR4450:
1880 		nxp_pr4450_fixup_config();
1881 		break;
1882 	}
1883 }
1884 
1885 static void r4k_cache_error_setup(void)
1886 {
1887 	extern char __weak except_vec2_generic;
1888 	extern char __weak except_vec2_sb1;
1889 
1890 	switch (current_cpu_type()) {
1891 	case CPU_SB1:
1892 	case CPU_SB1A:
1893 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1894 		break;
1895 
1896 	default:
1897 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1898 		break;
1899 	}
1900 }
1901 
1902 void r4k_cache_init(void)
1903 {
1904 	extern void build_clear_page(void);
1905 	extern void build_copy_page(void);
1906 	struct cpuinfo_mips *c = &current_cpu_data;
1907 
1908 	probe_pcache();
1909 	probe_vcache();
1910 	setup_scache();
1911 
1912 	r4k_blast_dcache_page_setup();
1913 	r4k_blast_dcache_page_indexed_setup();
1914 	r4k_blast_dcache_setup();
1915 	r4k_blast_icache_page_setup();
1916 	r4k_blast_icache_page_indexed_setup();
1917 	r4k_blast_icache_setup();
1918 	r4k_blast_scache_page_setup();
1919 	r4k_blast_scache_page_indexed_setup();
1920 	r4k_blast_scache_setup();
1921 #ifdef CONFIG_EVA
1922 	r4k_blast_dcache_user_page_setup();
1923 	r4k_blast_icache_user_page_setup();
1924 #endif
1925 
1926 	/*
1927 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1928 	 * This code supports virtually indexed processors and will be
1929 	 * unnecessarily inefficient on physically indexed processors.
1930 	 */
1931 	if (c->dcache.linesz && cpu_has_dc_aliases)
1932 		shm_align_mask = max_t( unsigned long,
1933 					c->dcache.sets * c->dcache.linesz - 1,
1934 					PAGE_SIZE - 1);
1935 	else
1936 		shm_align_mask = PAGE_SIZE-1;
1937 
1938 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1939 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1940 
1941 	flush_cache_all		= cache_noop;
1942 	__flush_cache_all	= r4k___flush_cache_all;
1943 	flush_cache_mm		= r4k_flush_cache_mm;
1944 	flush_cache_page	= r4k_flush_cache_page;
1945 	flush_cache_range	= r4k_flush_cache_range;
1946 
1947 	__flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1948 
1949 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1950 	flush_icache_all	= r4k_flush_icache_all;
1951 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1952 	flush_data_cache_page	= r4k_flush_data_cache_page;
1953 	flush_icache_range	= r4k_flush_icache_range;
1954 	local_flush_icache_range	= local_r4k_flush_icache_range;
1955 	__flush_icache_user_range	= r4k_flush_icache_user_range;
1956 	__local_flush_icache_user_range	= local_r4k_flush_icache_user_range;
1957 
1958 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
1959 # if defined(CONFIG_DMA_PERDEV_COHERENT)
1960 	if (0) {
1961 # else
1962 	if ((coherentio == IO_COHERENCE_ENABLED) ||
1963 	    ((coherentio == IO_COHERENCE_DEFAULT) && hw_coherentio)) {
1964 # endif
1965 		_dma_cache_wback_inv	= (void *)cache_noop;
1966 		_dma_cache_wback	= (void *)cache_noop;
1967 		_dma_cache_inv		= (void *)cache_noop;
1968 	} else {
1969 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1970 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1971 		_dma_cache_inv		= r4k_dma_cache_inv;
1972 	}
1973 #endif
1974 
1975 	build_clear_page();
1976 	build_copy_page();
1977 
1978 	/*
1979 	 * We want to run CMP kernels on core with and without coherent
1980 	 * caches. Therefore, do not use CONFIG_MIPS_CMP to decide whether
1981 	 * or not to flush caches.
1982 	 */
1983 	local_r4k___flush_cache_all(NULL);
1984 
1985 	coherency_setup();
1986 	board_cache_error_setup = r4k_cache_error_setup;
1987 
1988 	/*
1989 	 * Per-CPU overrides
1990 	 */
1991 	switch (current_cpu_type()) {
1992 	case CPU_BMIPS4350:
1993 	case CPU_BMIPS4380:
1994 		/* No IPI is needed because all CPUs share the same D$ */
1995 		flush_data_cache_page = r4k_blast_dcache_page;
1996 		break;
1997 	case CPU_BMIPS5000:
1998 		/* We lose our superpowers if L2 is disabled */
1999 		if (c->scache.flags & MIPS_CACHE_NOT_PRESENT)
2000 			break;
2001 
2002 		/* I$ fills from D$ just by emptying the write buffers */
2003 		flush_cache_page = (void *)b5k_instruction_hazard;
2004 		flush_cache_range = (void *)b5k_instruction_hazard;
2005 		flush_cache_sigtramp = (void *)b5k_instruction_hazard;
2006 		local_flush_data_cache_page = (void *)b5k_instruction_hazard;
2007 		flush_data_cache_page = (void *)b5k_instruction_hazard;
2008 		flush_icache_range = (void *)b5k_instruction_hazard;
2009 		local_flush_icache_range = (void *)b5k_instruction_hazard;
2010 
2011 
2012 		/* Optimization: an L2 flush implicitly flushes the L1 */
2013 		current_cpu_data.options |= MIPS_CPU_INCLUSIVE_CACHES;
2014 		break;
2015 	case CPU_LOONGSON3:
2016 		/* Loongson-3 maintains cache coherency by hardware */
2017 		__flush_cache_all	= cache_noop;
2018 		__flush_cache_vmap	= cache_noop;
2019 		__flush_cache_vunmap	= cache_noop;
2020 		__flush_kernel_vmap_range = (void *)cache_noop;
2021 		flush_cache_mm		= (void *)cache_noop;
2022 		flush_cache_page	= (void *)cache_noop;
2023 		flush_cache_range	= (void *)cache_noop;
2024 		flush_cache_sigtramp	= (void *)cache_noop;
2025 		flush_icache_all	= (void *)cache_noop;
2026 		flush_data_cache_page	= (void *)cache_noop;
2027 		local_flush_data_cache_page	= (void *)cache_noop;
2028 		break;
2029 	}
2030 }
2031 
2032 static int r4k_cache_pm_notifier(struct notifier_block *self, unsigned long cmd,
2033 			       void *v)
2034 {
2035 	switch (cmd) {
2036 	case CPU_PM_ENTER_FAILED:
2037 	case CPU_PM_EXIT:
2038 		coherency_setup();
2039 		break;
2040 	}
2041 
2042 	return NOTIFY_OK;
2043 }
2044 
2045 static struct notifier_block r4k_cache_pm_notifier_block = {
2046 	.notifier_call = r4k_cache_pm_notifier,
2047 };
2048 
2049 int __init r4k_cache_init_pm(void)
2050 {
2051 	return cpu_pm_register_notifier(&r4k_cache_pm_notifier_block);
2052 }
2053 arch_initcall(r4k_cache_init_pm);
2054