xref: /openbmc/linux/arch/mips/mm/c-r4k.c (revision 9b1c2ecf)
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 #include <linux/dma-map-ops.h> /* for dma_default_coherent */
23 
24 #include <asm/bcache.h>
25 #include <asm/bootinfo.h>
26 #include <asm/cache.h>
27 #include <asm/cacheops.h>
28 #include <asm/cpu.h>
29 #include <asm/cpu-features.h>
30 #include <asm/cpu-type.h>
31 #include <asm/io.h>
32 #include <asm/page.h>
33 #include <asm/r4kcache.h>
34 #include <asm/sections.h>
35 #include <asm/mmu_context.h>
36 #include <asm/cacheflush.h> /* for run_uncached() */
37 #include <asm/traps.h>
38 #include <asm/mips-cps.h>
39 
40 /*
41  * Bits describing what cache ops an SMP callback function may perform.
42  *
43  * R4K_HIT   -	Virtual user or kernel address based cache operations. The
44  *		active_mm must be checked before using user addresses, falling
45  *		back to kmap.
46  * R4K_INDEX -	Index based cache operations.
47  */
48 
49 #define R4K_HIT		BIT(0)
50 #define R4K_INDEX	BIT(1)
51 
52 /**
53  * r4k_op_needs_ipi() - Decide if a cache op needs to be done on every core.
54  * @type:	Type of cache operations (R4K_HIT or R4K_INDEX).
55  *
56  * Decides whether a cache op needs to be performed on every core in the system.
57  * This may change depending on the @type of cache operation, as well as the set
58  * of online CPUs, so preemption should be disabled by the caller to prevent CPU
59  * hotplug from changing the result.
60  *
61  * Returns:	1 if the cache operation @type should be done on every core in
62  *		the system.
63  *		0 if the cache operation @type is globalized and only needs to
64  *		be performed on a simple CPU.
65  */
66 static inline bool r4k_op_needs_ipi(unsigned int type)
67 {
68 	/* The MIPS Coherence Manager (CM) globalizes address-based cache ops */
69 	if (type == R4K_HIT && mips_cm_present())
70 		return false;
71 
72 	/*
73 	 * Hardware doesn't globalize the required cache ops, so SMP calls may
74 	 * be needed, but only if there are foreign CPUs (non-siblings with
75 	 * separate caches).
76 	 */
77 	/* cpu_foreign_map[] undeclared when !CONFIG_SMP */
78 #ifdef CONFIG_SMP
79 	return !cpumask_empty(&cpu_foreign_map[0]);
80 #else
81 	return false;
82 #endif
83 }
84 
85 /*
86  * Special Variant of smp_call_function for use by cache functions:
87  *
88  *  o No return value
89  *  o collapses to normal function call on UP kernels
90  *  o collapses to normal function call on systems with a single shared
91  *    primary cache.
92  *  o doesn't disable interrupts on the local CPU
93  */
94 static inline void r4k_on_each_cpu(unsigned int type,
95 				   void (*func)(void *info), void *info)
96 {
97 	preempt_disable();
98 	if (r4k_op_needs_ipi(type))
99 		smp_call_function_many(&cpu_foreign_map[smp_processor_id()],
100 				       func, info, 1);
101 	func(info);
102 	preempt_enable();
103 }
104 
105 /*
106  * Must die.
107  */
108 static unsigned long icache_size __read_mostly;
109 static unsigned long dcache_size __read_mostly;
110 static unsigned long vcache_size __read_mostly;
111 static unsigned long scache_size __read_mostly;
112 
113 /*
114  * Dummy cache handling routines for machines without boardcaches
115  */
116 static void cache_noop(void) {}
117 
118 static struct bcache_ops no_sc_ops = {
119 	.bc_enable = (void *)cache_noop,
120 	.bc_disable = (void *)cache_noop,
121 	.bc_wback_inv = (void *)cache_noop,
122 	.bc_inv = (void *)cache_noop
123 };
124 
125 struct bcache_ops *bcops = &no_sc_ops;
126 
127 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
128 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
129 
130 #define R4600_HIT_CACHEOP_WAR_IMPL					\
131 do {									\
132 	if (IS_ENABLED(CONFIG_WAR_R4600_V2_HIT_CACHEOP) &&		\
133 	    cpu_is_r4600_v2_x())					\
134 		*(volatile unsigned long *)CKSEG1;			\
135 	if (IS_ENABLED(CONFIG_WAR_R4600_V1_HIT_CACHEOP))					\
136 		__asm__ __volatile__("nop;nop;nop;nop");		\
137 } while (0)
138 
139 static void (*r4k_blast_dcache_page)(unsigned long addr);
140 
141 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
142 {
143 	R4600_HIT_CACHEOP_WAR_IMPL;
144 	blast_dcache32_page(addr);
145 }
146 
147 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
148 {
149 	blast_dcache64_page(addr);
150 }
151 
152 static inline void r4k_blast_dcache_page_dc128(unsigned long addr)
153 {
154 	blast_dcache128_page(addr);
155 }
156 
157 static void r4k_blast_dcache_page_setup(void)
158 {
159 	unsigned long  dc_lsize = cpu_dcache_line_size();
160 
161 	switch (dc_lsize) {
162 	case 0:
163 		r4k_blast_dcache_page = (void *)cache_noop;
164 		break;
165 	case 16:
166 		r4k_blast_dcache_page = blast_dcache16_page;
167 		break;
168 	case 32:
169 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
170 		break;
171 	case 64:
172 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
173 		break;
174 	case 128:
175 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc128;
176 		break;
177 	default:
178 		break;
179 	}
180 }
181 
182 #ifndef CONFIG_EVA
183 #define r4k_blast_dcache_user_page  r4k_blast_dcache_page
184 #else
185 
186 static void (*r4k_blast_dcache_user_page)(unsigned long addr);
187 
188 static void r4k_blast_dcache_user_page_setup(void)
189 {
190 	unsigned long  dc_lsize = cpu_dcache_line_size();
191 
192 	if (dc_lsize == 0)
193 		r4k_blast_dcache_user_page = (void *)cache_noop;
194 	else if (dc_lsize == 16)
195 		r4k_blast_dcache_user_page = blast_dcache16_user_page;
196 	else if (dc_lsize == 32)
197 		r4k_blast_dcache_user_page = blast_dcache32_user_page;
198 	else if (dc_lsize == 64)
199 		r4k_blast_dcache_user_page = blast_dcache64_user_page;
200 }
201 
202 #endif
203 
204 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
205 
206 static void r4k_blast_dcache_page_indexed_setup(void)
207 {
208 	unsigned long dc_lsize = cpu_dcache_line_size();
209 
210 	if (dc_lsize == 0)
211 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
212 	else if (dc_lsize == 16)
213 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
214 	else if (dc_lsize == 32)
215 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
216 	else if (dc_lsize == 64)
217 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
218 	else if (dc_lsize == 128)
219 		r4k_blast_dcache_page_indexed = blast_dcache128_page_indexed;
220 }
221 
222 void (* r4k_blast_dcache)(void);
223 EXPORT_SYMBOL(r4k_blast_dcache);
224 
225 static void r4k_blast_dcache_setup(void)
226 {
227 	unsigned long dc_lsize = cpu_dcache_line_size();
228 
229 	if (dc_lsize == 0)
230 		r4k_blast_dcache = (void *)cache_noop;
231 	else if (dc_lsize == 16)
232 		r4k_blast_dcache = blast_dcache16;
233 	else if (dc_lsize == 32)
234 		r4k_blast_dcache = blast_dcache32;
235 	else if (dc_lsize == 64)
236 		r4k_blast_dcache = blast_dcache64;
237 	else if (dc_lsize == 128)
238 		r4k_blast_dcache = blast_dcache128;
239 }
240 
241 /* force code alignment (used for CONFIG_WAR_TX49XX_ICACHE_INDEX_INV) */
242 #define JUMP_TO_ALIGN(order) \
243 	__asm__ __volatile__( \
244 		"b\t1f\n\t" \
245 		".align\t" #order "\n\t" \
246 		"1:\n\t" \
247 		)
248 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
249 #define CACHE32_UNROLL32_ALIGN2 JUMP_TO_ALIGN(11)
250 
251 static inline void blast_r4600_v1_icache32(void)
252 {
253 	unsigned long flags;
254 
255 	local_irq_save(flags);
256 	blast_icache32();
257 	local_irq_restore(flags);
258 }
259 
260 static inline void tx49_blast_icache32(void)
261 {
262 	unsigned long start = INDEX_BASE;
263 	unsigned long end = start + current_cpu_data.icache.waysize;
264 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
265 	unsigned long ws_end = current_cpu_data.icache.ways <<
266 			       current_cpu_data.icache.waybit;
267 	unsigned long ws, addr;
268 
269 	CACHE32_UNROLL32_ALIGN2;
270 	/* I'm in even chunk.  blast odd chunks */
271 	for (ws = 0; ws < ws_end; ws += ws_inc)
272 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
273 			cache_unroll(32, kernel_cache, Index_Invalidate_I,
274 				     addr | ws, 32);
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 			cache_unroll(32, kernel_cache, Index_Invalidate_I,
280 				     addr | ws, 32);
281 }
282 
283 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
284 {
285 	unsigned long flags;
286 
287 	local_irq_save(flags);
288 	blast_icache32_page_indexed(page);
289 	local_irq_restore(flags);
290 }
291 
292 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
293 {
294 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
295 	unsigned long start = INDEX_BASE + (page & indexmask);
296 	unsigned long end = start + PAGE_SIZE;
297 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
298 	unsigned long ws_end = current_cpu_data.icache.ways <<
299 			       current_cpu_data.icache.waybit;
300 	unsigned long ws, addr;
301 
302 	CACHE32_UNROLL32_ALIGN2;
303 	/* I'm in even chunk.  blast odd chunks */
304 	for (ws = 0; ws < ws_end; ws += ws_inc)
305 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
306 			cache_unroll(32, kernel_cache, Index_Invalidate_I,
307 				     addr | ws, 32);
308 	CACHE32_UNROLL32_ALIGN;
309 	/* I'm in odd chunk.  blast even chunks */
310 	for (ws = 0; ws < ws_end; ws += ws_inc)
311 		for (addr = start; addr < end; addr += 0x400 * 2)
312 			cache_unroll(32, kernel_cache, Index_Invalidate_I,
313 				     addr | ws, 32);
314 }
315 
316 static void (* r4k_blast_icache_page)(unsigned long addr);
317 
318 static void r4k_blast_icache_page_setup(void)
319 {
320 	unsigned long ic_lsize = cpu_icache_line_size();
321 
322 	if (ic_lsize == 0)
323 		r4k_blast_icache_page = (void *)cache_noop;
324 	else if (ic_lsize == 16)
325 		r4k_blast_icache_page = blast_icache16_page;
326 	else if (ic_lsize == 32 && current_cpu_type() == CPU_LOONGSON2EF)
327 		r4k_blast_icache_page = loongson2_blast_icache32_page;
328 	else if (ic_lsize == 32)
329 		r4k_blast_icache_page = blast_icache32_page;
330 	else if (ic_lsize == 64)
331 		r4k_blast_icache_page = blast_icache64_page;
332 	else if (ic_lsize == 128)
333 		r4k_blast_icache_page = blast_icache128_page;
334 }
335 
336 #ifndef CONFIG_EVA
337 #define r4k_blast_icache_user_page  r4k_blast_icache_page
338 #else
339 
340 static void (*r4k_blast_icache_user_page)(unsigned long addr);
341 
342 static void r4k_blast_icache_user_page_setup(void)
343 {
344 	unsigned long ic_lsize = cpu_icache_line_size();
345 
346 	if (ic_lsize == 0)
347 		r4k_blast_icache_user_page = (void *)cache_noop;
348 	else if (ic_lsize == 16)
349 		r4k_blast_icache_user_page = blast_icache16_user_page;
350 	else if (ic_lsize == 32)
351 		r4k_blast_icache_user_page = blast_icache32_user_page;
352 	else if (ic_lsize == 64)
353 		r4k_blast_icache_user_page = blast_icache64_user_page;
354 }
355 
356 #endif
357 
358 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
359 
360 static void r4k_blast_icache_page_indexed_setup(void)
361 {
362 	unsigned long ic_lsize = cpu_icache_line_size();
363 
364 	if (ic_lsize == 0)
365 		r4k_blast_icache_page_indexed = (void *)cache_noop;
366 	else if (ic_lsize == 16)
367 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
368 	else if (ic_lsize == 32) {
369 		if (IS_ENABLED(CONFIG_WAR_R4600_V1_INDEX_ICACHEOP) &&
370 		    cpu_is_r4600_v1_x())
371 			r4k_blast_icache_page_indexed =
372 				blast_icache32_r4600_v1_page_indexed;
373 		else if (IS_ENABLED(CONFIG_WAR_TX49XX_ICACHE_INDEX_INV))
374 			r4k_blast_icache_page_indexed =
375 				tx49_blast_icache32_page_indexed;
376 		else if (current_cpu_type() == CPU_LOONGSON2EF)
377 			r4k_blast_icache_page_indexed =
378 				loongson2_blast_icache32_page_indexed;
379 		else
380 			r4k_blast_icache_page_indexed =
381 				blast_icache32_page_indexed;
382 	} else if (ic_lsize == 64)
383 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
384 }
385 
386 void (* r4k_blast_icache)(void);
387 EXPORT_SYMBOL(r4k_blast_icache);
388 
389 static void r4k_blast_icache_setup(void)
390 {
391 	unsigned long ic_lsize = cpu_icache_line_size();
392 
393 	if (ic_lsize == 0)
394 		r4k_blast_icache = (void *)cache_noop;
395 	else if (ic_lsize == 16)
396 		r4k_blast_icache = blast_icache16;
397 	else if (ic_lsize == 32) {
398 		if (IS_ENABLED(CONFIG_WAR_R4600_V1_INDEX_ICACHEOP) &&
399 		    cpu_is_r4600_v1_x())
400 			r4k_blast_icache = blast_r4600_v1_icache32;
401 		else if (IS_ENABLED(CONFIG_WAR_TX49XX_ICACHE_INDEX_INV))
402 			r4k_blast_icache = tx49_blast_icache32;
403 		else if (current_cpu_type() == CPU_LOONGSON2EF)
404 			r4k_blast_icache = loongson2_blast_icache32;
405 		else
406 			r4k_blast_icache = blast_icache32;
407 	} else if (ic_lsize == 64)
408 		r4k_blast_icache = blast_icache64;
409 	else if (ic_lsize == 128)
410 		r4k_blast_icache = blast_icache128;
411 }
412 
413 static void (* r4k_blast_scache_page)(unsigned long addr);
414 
415 static void r4k_blast_scache_page_setup(void)
416 {
417 	unsigned long sc_lsize = cpu_scache_line_size();
418 
419 	if (scache_size == 0)
420 		r4k_blast_scache_page = (void *)cache_noop;
421 	else if (sc_lsize == 16)
422 		r4k_blast_scache_page = blast_scache16_page;
423 	else if (sc_lsize == 32)
424 		r4k_blast_scache_page = blast_scache32_page;
425 	else if (sc_lsize == 64)
426 		r4k_blast_scache_page = blast_scache64_page;
427 	else if (sc_lsize == 128)
428 		r4k_blast_scache_page = blast_scache128_page;
429 }
430 
431 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
432 
433 static void r4k_blast_scache_page_indexed_setup(void)
434 {
435 	unsigned long sc_lsize = cpu_scache_line_size();
436 
437 	if (scache_size == 0)
438 		r4k_blast_scache_page_indexed = (void *)cache_noop;
439 	else if (sc_lsize == 16)
440 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
441 	else if (sc_lsize == 32)
442 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
443 	else if (sc_lsize == 64)
444 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
445 	else if (sc_lsize == 128)
446 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
447 }
448 
449 static void (* r4k_blast_scache)(void);
450 
451 static void r4k_blast_scache_setup(void)
452 {
453 	unsigned long sc_lsize = cpu_scache_line_size();
454 
455 	if (scache_size == 0)
456 		r4k_blast_scache = (void *)cache_noop;
457 	else if (sc_lsize == 16)
458 		r4k_blast_scache = blast_scache16;
459 	else if (sc_lsize == 32)
460 		r4k_blast_scache = blast_scache32;
461 	else if (sc_lsize == 64)
462 		r4k_blast_scache = blast_scache64;
463 	else if (sc_lsize == 128)
464 		r4k_blast_scache = blast_scache128;
465 }
466 
467 static void (*r4k_blast_scache_node)(long node);
468 
469 static void r4k_blast_scache_node_setup(void)
470 {
471 	unsigned long sc_lsize = cpu_scache_line_size();
472 
473 	if (current_cpu_type() != CPU_LOONGSON64)
474 		r4k_blast_scache_node = (void *)cache_noop;
475 	else if (sc_lsize == 16)
476 		r4k_blast_scache_node = blast_scache16_node;
477 	else if (sc_lsize == 32)
478 		r4k_blast_scache_node = blast_scache32_node;
479 	else if (sc_lsize == 64)
480 		r4k_blast_scache_node = blast_scache64_node;
481 	else if (sc_lsize == 128)
482 		r4k_blast_scache_node = blast_scache128_node;
483 }
484 
485 static inline void local_r4k___flush_cache_all(void * args)
486 {
487 	switch (current_cpu_type()) {
488 	case CPU_LOONGSON2EF:
489 	case CPU_R4000SC:
490 	case CPU_R4000MC:
491 	case CPU_R4400SC:
492 	case CPU_R4400MC:
493 	case CPU_R10000:
494 	case CPU_R12000:
495 	case CPU_R14000:
496 	case CPU_R16000:
497 		/*
498 		 * These caches are inclusive caches, that is, if something
499 		 * is not cached in the S-cache, we know it also won't be
500 		 * in one of the primary caches.
501 		 */
502 		r4k_blast_scache();
503 		break;
504 
505 	case CPU_LOONGSON64:
506 		/* Use get_ebase_cpunum() for both NUMA=y/n */
507 		r4k_blast_scache_node(get_ebase_cpunum() >> 2);
508 		break;
509 
510 	case CPU_BMIPS5000:
511 		r4k_blast_scache();
512 		__sync();
513 		break;
514 
515 	default:
516 		r4k_blast_dcache();
517 		r4k_blast_icache();
518 		break;
519 	}
520 }
521 
522 static void r4k___flush_cache_all(void)
523 {
524 	r4k_on_each_cpu(R4K_INDEX, local_r4k___flush_cache_all, NULL);
525 }
526 
527 /**
528  * has_valid_asid() - Determine if an mm already has an ASID.
529  * @mm:		Memory map.
530  * @type:	R4K_HIT or R4K_INDEX, type of cache op.
531  *
532  * Determines whether @mm already has an ASID on any of the CPUs which cache ops
533  * of type @type within an r4k_on_each_cpu() call will affect. If
534  * r4k_on_each_cpu() does an SMP call to a single VPE in each core, then the
535  * scope of the operation is confined to sibling CPUs, otherwise all online CPUs
536  * will need to be checked.
537  *
538  * Must be called in non-preemptive context.
539  *
540  * Returns:	1 if the CPUs affected by @type cache ops have an ASID for @mm.
541  *		0 otherwise.
542  */
543 static inline int has_valid_asid(const struct mm_struct *mm, unsigned int type)
544 {
545 	unsigned int i;
546 	const cpumask_t *mask = cpu_present_mask;
547 
548 	if (cpu_has_mmid)
549 		return cpu_context(0, mm) != 0;
550 
551 	/* cpu_sibling_map[] undeclared when !CONFIG_SMP */
552 #ifdef CONFIG_SMP
553 	/*
554 	 * If r4k_on_each_cpu does SMP calls, it does them to a single VPE in
555 	 * each foreign core, so we only need to worry about siblings.
556 	 * Otherwise we need to worry about all present CPUs.
557 	 */
558 	if (r4k_op_needs_ipi(type))
559 		mask = &cpu_sibling_map[smp_processor_id()];
560 #endif
561 	for_each_cpu(i, mask)
562 		if (cpu_context(i, mm))
563 			return 1;
564 	return 0;
565 }
566 
567 static void r4k__flush_cache_vmap(void)
568 {
569 	r4k_blast_dcache();
570 }
571 
572 static void r4k__flush_cache_vunmap(void)
573 {
574 	r4k_blast_dcache();
575 }
576 
577 /*
578  * Note: flush_tlb_range() assumes flush_cache_range() sufficiently flushes
579  * whole caches when vma is executable.
580  */
581 static inline void local_r4k_flush_cache_range(void * args)
582 {
583 	struct vm_area_struct *vma = args;
584 	int exec = vma->vm_flags & VM_EXEC;
585 
586 	if (!has_valid_asid(vma->vm_mm, R4K_INDEX))
587 		return;
588 
589 	/*
590 	 * If dcache can alias, we must blast it since mapping is changing.
591 	 * If executable, we must ensure any dirty lines are written back far
592 	 * enough to be visible to icache.
593 	 */
594 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
595 		r4k_blast_dcache();
596 	/* If executable, blast stale lines from icache */
597 	if (exec)
598 		r4k_blast_icache();
599 }
600 
601 static void r4k_flush_cache_range(struct vm_area_struct *vma,
602 	unsigned long start, unsigned long end)
603 {
604 	int exec = vma->vm_flags & VM_EXEC;
605 
606 	if (cpu_has_dc_aliases || exec)
607 		r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_range, vma);
608 }
609 
610 static inline void local_r4k_flush_cache_mm(void * args)
611 {
612 	struct mm_struct *mm = args;
613 
614 	if (!has_valid_asid(mm, R4K_INDEX))
615 		return;
616 
617 	/*
618 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
619 	 * only flush the primary caches but R1x000 behave sane ...
620 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
621 	 * caches, so we can bail out early.
622 	 */
623 	if (current_cpu_type() == CPU_R4000SC ||
624 	    current_cpu_type() == CPU_R4000MC ||
625 	    current_cpu_type() == CPU_R4400SC ||
626 	    current_cpu_type() == CPU_R4400MC) {
627 		r4k_blast_scache();
628 		return;
629 	}
630 
631 	r4k_blast_dcache();
632 }
633 
634 static void r4k_flush_cache_mm(struct mm_struct *mm)
635 {
636 	if (!cpu_has_dc_aliases)
637 		return;
638 
639 	r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_mm, mm);
640 }
641 
642 struct flush_cache_page_args {
643 	struct vm_area_struct *vma;
644 	unsigned long addr;
645 	unsigned long pfn;
646 };
647 
648 static inline void local_r4k_flush_cache_page(void *args)
649 {
650 	struct flush_cache_page_args *fcp_args = args;
651 	struct vm_area_struct *vma = fcp_args->vma;
652 	unsigned long addr = fcp_args->addr;
653 	struct page *page = pfn_to_page(fcp_args->pfn);
654 	int exec = vma->vm_flags & VM_EXEC;
655 	struct mm_struct *mm = vma->vm_mm;
656 	int map_coherent = 0;
657 	pmd_t *pmdp;
658 	pte_t *ptep;
659 	void *vaddr;
660 
661 	/*
662 	 * If owns no valid ASID yet, cannot possibly have gotten
663 	 * this page into the cache.
664 	 */
665 	if (!has_valid_asid(mm, R4K_HIT))
666 		return;
667 
668 	addr &= PAGE_MASK;
669 	pmdp = pmd_off(mm, addr);
670 	ptep = pte_offset_kernel(pmdp, addr);
671 
672 	/*
673 	 * If the page isn't marked valid, the page cannot possibly be
674 	 * in the cache.
675 	 */
676 	if (!(pte_present(*ptep)))
677 		return;
678 
679 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
680 		vaddr = NULL;
681 	else {
682 		/*
683 		 * Use kmap_coherent or kmap_atomic to do flushes for
684 		 * another ASID than the current one.
685 		 */
686 		map_coherent = (cpu_has_dc_aliases &&
687 				page_mapcount(page) &&
688 				!Page_dcache_dirty(page));
689 		if (map_coherent)
690 			vaddr = kmap_coherent(page, addr);
691 		else
692 			vaddr = kmap_atomic(page);
693 		addr = (unsigned long)vaddr;
694 	}
695 
696 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
697 		vaddr ? r4k_blast_dcache_page(addr) :
698 			r4k_blast_dcache_user_page(addr);
699 		if (exec && !cpu_icache_snoops_remote_store)
700 			r4k_blast_scache_page(addr);
701 	}
702 	if (exec) {
703 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
704 			drop_mmu_context(mm);
705 		} else
706 			vaddr ? r4k_blast_icache_page(addr) :
707 				r4k_blast_icache_user_page(addr);
708 	}
709 
710 	if (vaddr) {
711 		if (map_coherent)
712 			kunmap_coherent();
713 		else
714 			kunmap_atomic(vaddr);
715 	}
716 }
717 
718 static void r4k_flush_cache_page(struct vm_area_struct *vma,
719 	unsigned long addr, unsigned long pfn)
720 {
721 	struct flush_cache_page_args args;
722 
723 	args.vma = vma;
724 	args.addr = addr;
725 	args.pfn = pfn;
726 
727 	r4k_on_each_cpu(R4K_HIT, local_r4k_flush_cache_page, &args);
728 }
729 
730 static inline void local_r4k_flush_data_cache_page(void * addr)
731 {
732 	r4k_blast_dcache_page((unsigned long) addr);
733 }
734 
735 static void r4k_flush_data_cache_page(unsigned long addr)
736 {
737 	if (in_atomic())
738 		local_r4k_flush_data_cache_page((void *)addr);
739 	else
740 		r4k_on_each_cpu(R4K_HIT, local_r4k_flush_data_cache_page,
741 				(void *) addr);
742 }
743 
744 struct flush_icache_range_args {
745 	unsigned long start;
746 	unsigned long end;
747 	unsigned int type;
748 	bool user;
749 };
750 
751 static inline void __local_r4k_flush_icache_range(unsigned long start,
752 						  unsigned long end,
753 						  unsigned int type,
754 						  bool user)
755 {
756 	if (!cpu_has_ic_fills_f_dc) {
757 		if (type == R4K_INDEX ||
758 		    (type & R4K_INDEX && end - start >= dcache_size)) {
759 			r4k_blast_dcache();
760 		} else {
761 			R4600_HIT_CACHEOP_WAR_IMPL;
762 			if (user)
763 				protected_blast_dcache_range(start, end);
764 			else
765 				blast_dcache_range(start, end);
766 		}
767 	}
768 
769 	if (type == R4K_INDEX ||
770 	    (type & R4K_INDEX && end - start > icache_size))
771 		r4k_blast_icache();
772 	else {
773 		switch (boot_cpu_type()) {
774 		case CPU_LOONGSON2EF:
775 			protected_loongson2_blast_icache_range(start, end);
776 			break;
777 
778 		default:
779 			if (user)
780 				protected_blast_icache_range(start, end);
781 			else
782 				blast_icache_range(start, end);
783 			break;
784 		}
785 	}
786 }
787 
788 static inline void local_r4k_flush_icache_range(unsigned long start,
789 						unsigned long end)
790 {
791 	__local_r4k_flush_icache_range(start, end, R4K_HIT | R4K_INDEX, false);
792 }
793 
794 static inline void local_r4k_flush_icache_user_range(unsigned long start,
795 						     unsigned long end)
796 {
797 	__local_r4k_flush_icache_range(start, end, R4K_HIT | R4K_INDEX, true);
798 }
799 
800 static inline void local_r4k_flush_icache_range_ipi(void *args)
801 {
802 	struct flush_icache_range_args *fir_args = args;
803 	unsigned long start = fir_args->start;
804 	unsigned long end = fir_args->end;
805 	unsigned int type = fir_args->type;
806 	bool user = fir_args->user;
807 
808 	__local_r4k_flush_icache_range(start, end, type, user);
809 }
810 
811 static void __r4k_flush_icache_range(unsigned long start, unsigned long end,
812 				     bool user)
813 {
814 	struct flush_icache_range_args args;
815 	unsigned long size, cache_size;
816 
817 	args.start = start;
818 	args.end = end;
819 	args.type = R4K_HIT | R4K_INDEX;
820 	args.user = user;
821 
822 	/*
823 	 * Indexed cache ops require an SMP call.
824 	 * Consider if that can or should be avoided.
825 	 */
826 	preempt_disable();
827 	if (r4k_op_needs_ipi(R4K_INDEX) && !r4k_op_needs_ipi(R4K_HIT)) {
828 		/*
829 		 * If address-based cache ops don't require an SMP call, then
830 		 * use them exclusively for small flushes.
831 		 */
832 		size = end - start;
833 		cache_size = icache_size;
834 		if (!cpu_has_ic_fills_f_dc) {
835 			size *= 2;
836 			cache_size += dcache_size;
837 		}
838 		if (size <= cache_size)
839 			args.type &= ~R4K_INDEX;
840 	}
841 	r4k_on_each_cpu(args.type, local_r4k_flush_icache_range_ipi, &args);
842 	preempt_enable();
843 	instruction_hazard();
844 }
845 
846 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
847 {
848 	return __r4k_flush_icache_range(start, end, false);
849 }
850 
851 static void r4k_flush_icache_user_range(unsigned long start, unsigned long end)
852 {
853 	return __r4k_flush_icache_range(start, end, true);
854 }
855 
856 #ifdef CONFIG_DMA_NONCOHERENT
857 
858 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
859 {
860 	/* Catch bad driver code */
861 	if (WARN_ON(size == 0))
862 		return;
863 
864 	preempt_disable();
865 	if (cpu_has_inclusive_pcaches) {
866 		if (size >= scache_size) {
867 			if (current_cpu_type() != CPU_LOONGSON64)
868 				r4k_blast_scache();
869 			else
870 				r4k_blast_scache_node(pa_to_nid(addr));
871 		} else {
872 			blast_scache_range(addr, addr + size);
873 		}
874 		preempt_enable();
875 		__sync();
876 		return;
877 	}
878 
879 	/*
880 	 * Either no secondary cache or the available caches don't have the
881 	 * subset property so we have to flush the primary caches
882 	 * explicitly.
883 	 * If we would need IPI to perform an INDEX-type operation, then
884 	 * we have to use the HIT-type alternative as IPI cannot be used
885 	 * here due to interrupts possibly being disabled.
886 	 */
887 	if (!r4k_op_needs_ipi(R4K_INDEX) && size >= dcache_size) {
888 		r4k_blast_dcache();
889 	} else {
890 		R4600_HIT_CACHEOP_WAR_IMPL;
891 		blast_dcache_range(addr, addr + size);
892 	}
893 	preempt_enable();
894 
895 	bc_wback_inv(addr, size);
896 	__sync();
897 }
898 
899 static void prefetch_cache_inv(unsigned long addr, unsigned long size)
900 {
901 	unsigned int linesz = cpu_scache_line_size();
902 	unsigned long addr0 = addr, addr1;
903 
904 	addr0 &= ~(linesz - 1);
905 	addr1 = (addr0 + size - 1) & ~(linesz - 1);
906 
907 	protected_writeback_scache_line(addr0);
908 	if (likely(addr1 != addr0))
909 		protected_writeback_scache_line(addr1);
910 	else
911 		return;
912 
913 	addr0 += linesz;
914 	if (likely(addr1 != addr0))
915 		protected_writeback_scache_line(addr0);
916 	else
917 		return;
918 
919 	addr1 -= linesz;
920 	if (likely(addr1 > addr0))
921 		protected_writeback_scache_line(addr0);
922 }
923 
924 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
925 {
926 	/* Catch bad driver code */
927 	if (WARN_ON(size == 0))
928 		return;
929 
930 	preempt_disable();
931 
932 	if (current_cpu_type() == CPU_BMIPS5000)
933 		prefetch_cache_inv(addr, size);
934 
935 	if (cpu_has_inclusive_pcaches) {
936 		if (size >= scache_size) {
937 			if (current_cpu_type() != CPU_LOONGSON64)
938 				r4k_blast_scache();
939 			else
940 				r4k_blast_scache_node(pa_to_nid(addr));
941 		} else {
942 			/*
943 			 * There is no clearly documented alignment requirement
944 			 * for the cache instruction on MIPS processors and
945 			 * some processors, among them the RM5200 and RM7000
946 			 * QED processors will throw an address error for cache
947 			 * hit ops with insufficient alignment.	 Solved by
948 			 * aligning the address to cache line size.
949 			 */
950 			blast_inv_scache_range(addr, addr + size);
951 		}
952 		preempt_enable();
953 		__sync();
954 		return;
955 	}
956 
957 	if (!r4k_op_needs_ipi(R4K_INDEX) && size >= dcache_size) {
958 		r4k_blast_dcache();
959 	} else {
960 		R4600_HIT_CACHEOP_WAR_IMPL;
961 		blast_inv_dcache_range(addr, addr + size);
962 	}
963 	preempt_enable();
964 
965 	bc_inv(addr, size);
966 	__sync();
967 }
968 #endif /* CONFIG_DMA_NONCOHERENT */
969 
970 static void r4k_flush_icache_all(void)
971 {
972 	if (cpu_has_vtag_icache)
973 		r4k_blast_icache();
974 }
975 
976 struct flush_kernel_vmap_range_args {
977 	unsigned long	vaddr;
978 	int		size;
979 };
980 
981 static inline void local_r4k_flush_kernel_vmap_range_index(void *args)
982 {
983 	/*
984 	 * Aliases only affect the primary caches so don't bother with
985 	 * S-caches or T-caches.
986 	 */
987 	r4k_blast_dcache();
988 }
989 
990 static inline void local_r4k_flush_kernel_vmap_range(void *args)
991 {
992 	struct flush_kernel_vmap_range_args *vmra = args;
993 	unsigned long vaddr = vmra->vaddr;
994 	int size = vmra->size;
995 
996 	/*
997 	 * Aliases only affect the primary caches so don't bother with
998 	 * S-caches or T-caches.
999 	 */
1000 	R4600_HIT_CACHEOP_WAR_IMPL;
1001 	blast_dcache_range(vaddr, vaddr + size);
1002 }
1003 
1004 static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
1005 {
1006 	struct flush_kernel_vmap_range_args args;
1007 
1008 	args.vaddr = (unsigned long) vaddr;
1009 	args.size = size;
1010 
1011 	if (size >= dcache_size)
1012 		r4k_on_each_cpu(R4K_INDEX,
1013 				local_r4k_flush_kernel_vmap_range_index, NULL);
1014 	else
1015 		r4k_on_each_cpu(R4K_HIT, local_r4k_flush_kernel_vmap_range,
1016 				&args);
1017 }
1018 
1019 static inline void rm7k_erratum31(void)
1020 {
1021 	const unsigned long ic_lsize = 32;
1022 	unsigned long addr;
1023 
1024 	/* RM7000 erratum #31. The icache is screwed at startup. */
1025 	write_c0_taglo(0);
1026 	write_c0_taghi(0);
1027 
1028 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
1029 		__asm__ __volatile__ (
1030 			".set push\n\t"
1031 			".set noreorder\n\t"
1032 			".set mips3\n\t"
1033 			"cache\t%1, 0(%0)\n\t"
1034 			"cache\t%1, 0x1000(%0)\n\t"
1035 			"cache\t%1, 0x2000(%0)\n\t"
1036 			"cache\t%1, 0x3000(%0)\n\t"
1037 			"cache\t%2, 0(%0)\n\t"
1038 			"cache\t%2, 0x1000(%0)\n\t"
1039 			"cache\t%2, 0x2000(%0)\n\t"
1040 			"cache\t%2, 0x3000(%0)\n\t"
1041 			"cache\t%1, 0(%0)\n\t"
1042 			"cache\t%1, 0x1000(%0)\n\t"
1043 			"cache\t%1, 0x2000(%0)\n\t"
1044 			"cache\t%1, 0x3000(%0)\n\t"
1045 			".set pop\n"
1046 			:
1047 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill_I));
1048 	}
1049 }
1050 
1051 static inline int alias_74k_erratum(struct cpuinfo_mips *c)
1052 {
1053 	unsigned int imp = c->processor_id & PRID_IMP_MASK;
1054 	unsigned int rev = c->processor_id & PRID_REV_MASK;
1055 	int present = 0;
1056 
1057 	/*
1058 	 * Early versions of the 74K do not update the cache tags on a
1059 	 * vtag miss/ptag hit which can occur in the case of KSEG0/KUSEG
1060 	 * aliases.  In this case it is better to treat the cache as always
1061 	 * having aliases.  Also disable the synonym tag update feature
1062 	 * where available.  In this case no opportunistic tag update will
1063 	 * happen where a load causes a virtual address miss but a physical
1064 	 * address hit during a D-cache look-up.
1065 	 */
1066 	switch (imp) {
1067 	case PRID_IMP_74K:
1068 		if (rev <= PRID_REV_ENCODE_332(2, 4, 0))
1069 			present = 1;
1070 		if (rev == PRID_REV_ENCODE_332(2, 4, 0))
1071 			write_c0_config6(read_c0_config6() | MTI_CONF6_SYND);
1072 		break;
1073 	case PRID_IMP_1074K:
1074 		if (rev <= PRID_REV_ENCODE_332(1, 1, 0)) {
1075 			present = 1;
1076 			write_c0_config6(read_c0_config6() | MTI_CONF6_SYND);
1077 		}
1078 		break;
1079 	default:
1080 		BUG();
1081 	}
1082 
1083 	return present;
1084 }
1085 
1086 static void b5k_instruction_hazard(void)
1087 {
1088 	__sync();
1089 	__sync();
1090 	__asm__ __volatile__(
1091 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1092 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1093 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1094 	"       nop; nop; nop; nop; nop; nop; nop; nop\n"
1095 	: : : "memory");
1096 }
1097 
1098 static char *way_string[] = { NULL, "direct mapped", "2-way",
1099 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way",
1100 	"9-way", "10-way", "11-way", "12-way",
1101 	"13-way", "14-way", "15-way", "16-way",
1102 };
1103 
1104 static void probe_pcache(void)
1105 {
1106 	struct cpuinfo_mips *c = &current_cpu_data;
1107 	unsigned int config = read_c0_config();
1108 	unsigned int prid = read_c0_prid();
1109 	int has_74k_erratum = 0;
1110 	unsigned long config1;
1111 	unsigned int lsize;
1112 
1113 	switch (current_cpu_type()) {
1114 	case CPU_R4600:			/* QED style two way caches? */
1115 	case CPU_R4700:
1116 	case CPU_R5000:
1117 	case CPU_NEVADA:
1118 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1119 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1120 		c->icache.ways = 2;
1121 		c->icache.waybit = __ffs(icache_size/2);
1122 
1123 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1124 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1125 		c->dcache.ways = 2;
1126 		c->dcache.waybit= __ffs(dcache_size/2);
1127 
1128 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1129 		break;
1130 
1131 	case CPU_R5500:
1132 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1133 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1134 		c->icache.ways = 2;
1135 		c->icache.waybit= 0;
1136 
1137 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1138 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1139 		c->dcache.ways = 2;
1140 		c->dcache.waybit = 0;
1141 
1142 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
1143 		break;
1144 
1145 	case CPU_TX49XX:
1146 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1147 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1148 		c->icache.ways = 4;
1149 		c->icache.waybit= 0;
1150 
1151 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1152 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1153 		c->dcache.ways = 4;
1154 		c->dcache.waybit = 0;
1155 
1156 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1157 		c->options |= MIPS_CPU_PREFETCH;
1158 		break;
1159 
1160 	case CPU_R4000PC:
1161 	case CPU_R4000SC:
1162 	case CPU_R4000MC:
1163 	case CPU_R4400PC:
1164 	case CPU_R4400SC:
1165 	case CPU_R4400MC:
1166 	case CPU_R4300:
1167 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1168 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1169 		c->icache.ways = 1;
1170 		c->icache.waybit = 0;	/* doesn't matter */
1171 
1172 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1173 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1174 		c->dcache.ways = 1;
1175 		c->dcache.waybit = 0;	/* does not matter */
1176 
1177 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1178 		break;
1179 
1180 	case CPU_R10000:
1181 	case CPU_R12000:
1182 	case CPU_R14000:
1183 	case CPU_R16000:
1184 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
1185 		c->icache.linesz = 64;
1186 		c->icache.ways = 2;
1187 		c->icache.waybit = 0;
1188 
1189 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
1190 		c->dcache.linesz = 32;
1191 		c->dcache.ways = 2;
1192 		c->dcache.waybit = 0;
1193 
1194 		c->options |= MIPS_CPU_PREFETCH;
1195 		break;
1196 
1197 	case CPU_RM7000:
1198 		rm7k_erratum31();
1199 
1200 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1201 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1202 		c->icache.ways = 4;
1203 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
1204 
1205 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1206 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1207 		c->dcache.ways = 4;
1208 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
1209 
1210 		c->options |= MIPS_CPU_CACHE_CDEX_P;
1211 		c->options |= MIPS_CPU_PREFETCH;
1212 		break;
1213 
1214 	case CPU_LOONGSON2EF:
1215 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
1216 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
1217 		if (prid & 0x3)
1218 			c->icache.ways = 4;
1219 		else
1220 			c->icache.ways = 2;
1221 		c->icache.waybit = 0;
1222 
1223 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1224 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1225 		if (prid & 0x3)
1226 			c->dcache.ways = 4;
1227 		else
1228 			c->dcache.ways = 2;
1229 		c->dcache.waybit = 0;
1230 		break;
1231 
1232 	case CPU_LOONGSON64:
1233 		config1 = read_c0_config1();
1234 		lsize = (config1 >> 19) & 7;
1235 		if (lsize)
1236 			c->icache.linesz = 2 << lsize;
1237 		else
1238 			c->icache.linesz = 0;
1239 		c->icache.sets = 64 << ((config1 >> 22) & 7);
1240 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1241 		icache_size = c->icache.sets *
1242 					  c->icache.ways *
1243 					  c->icache.linesz;
1244 		c->icache.waybit = 0;
1245 
1246 		lsize = (config1 >> 10) & 7;
1247 		if (lsize)
1248 			c->dcache.linesz = 2 << lsize;
1249 		else
1250 			c->dcache.linesz = 0;
1251 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
1252 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1253 		dcache_size = c->dcache.sets *
1254 					  c->dcache.ways *
1255 					  c->dcache.linesz;
1256 		c->dcache.waybit = 0;
1257 		if ((c->processor_id & (PRID_IMP_MASK | PRID_REV_MASK)) >=
1258 				(PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_0) ||
1259 				(c->processor_id & PRID_IMP_MASK) == PRID_IMP_LOONGSON_64R)
1260 			c->options |= MIPS_CPU_PREFETCH;
1261 		break;
1262 
1263 	case CPU_CAVIUM_OCTEON3:
1264 		/* For now lie about the number of ways. */
1265 		c->icache.linesz = 128;
1266 		c->icache.sets = 16;
1267 		c->icache.ways = 8;
1268 		c->icache.flags |= MIPS_CACHE_VTAG;
1269 		icache_size = c->icache.sets * c->icache.ways * c->icache.linesz;
1270 
1271 		c->dcache.linesz = 128;
1272 		c->dcache.ways = 8;
1273 		c->dcache.sets = 8;
1274 		dcache_size = c->dcache.sets * c->dcache.ways * c->dcache.linesz;
1275 		c->options |= MIPS_CPU_PREFETCH;
1276 		break;
1277 
1278 	default:
1279 		if (!(config & MIPS_CONF_M))
1280 			panic("Don't know how to probe P-caches on this cpu.");
1281 
1282 		/*
1283 		 * So we seem to be a MIPS32 or MIPS64 CPU
1284 		 * So let's probe the I-cache ...
1285 		 */
1286 		config1 = read_c0_config1();
1287 
1288 		lsize = (config1 >> 19) & 7;
1289 
1290 		/* IL == 7 is reserved */
1291 		if (lsize == 7)
1292 			panic("Invalid icache line size");
1293 
1294 		c->icache.linesz = lsize ? 2 << lsize : 0;
1295 
1296 		c->icache.sets = 32 << (((config1 >> 22) + 1) & 7);
1297 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1298 
1299 		icache_size = c->icache.sets *
1300 			      c->icache.ways *
1301 			      c->icache.linesz;
1302 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
1303 
1304 		if (config & MIPS_CONF_VI)
1305 			c->icache.flags |= MIPS_CACHE_VTAG;
1306 
1307 		/*
1308 		 * Now probe the MIPS32 / MIPS64 data cache.
1309 		 */
1310 		c->dcache.flags = 0;
1311 
1312 		lsize = (config1 >> 10) & 7;
1313 
1314 		/* DL == 7 is reserved */
1315 		if (lsize == 7)
1316 			panic("Invalid dcache line size");
1317 
1318 		c->dcache.linesz = lsize ? 2 << lsize : 0;
1319 
1320 		c->dcache.sets = 32 << (((config1 >> 13) + 1) & 7);
1321 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1322 
1323 		dcache_size = c->dcache.sets *
1324 			      c->dcache.ways *
1325 			      c->dcache.linesz;
1326 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
1327 
1328 		c->options |= MIPS_CPU_PREFETCH;
1329 		break;
1330 	}
1331 
1332 	/*
1333 	 * Processor configuration sanity check for the R4000SC erratum
1334 	 * #5.	With page sizes larger than 32kB there is no possibility
1335 	 * to get a VCE exception anymore so we don't care about this
1336 	 * misconfiguration.  The case is rather theoretical anyway;
1337 	 * presumably no vendor is shipping his hardware in the "bad"
1338 	 * configuration.
1339 	 */
1340 	if ((prid & PRID_IMP_MASK) == PRID_IMP_R4000 &&
1341 	    (prid & PRID_REV_MASK) < PRID_REV_R4400 &&
1342 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
1343 	    PAGE_SIZE <= 0x8000)
1344 		panic("Improper R4000SC processor configuration detected");
1345 
1346 	/* compute a couple of other cache variables */
1347 	c->icache.waysize = icache_size / c->icache.ways;
1348 	c->dcache.waysize = dcache_size / c->dcache.ways;
1349 
1350 	c->icache.sets = c->icache.linesz ?
1351 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
1352 	c->dcache.sets = c->dcache.linesz ?
1353 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
1354 
1355 	/*
1356 	 * R1x000 P-caches are odd in a positive way.  They're 32kB 2-way
1357 	 * virtually indexed so normally would suffer from aliases.  So
1358 	 * normally they'd suffer from aliases but magic in the hardware deals
1359 	 * with that for us so we don't need to take care ourselves.
1360 	 */
1361 	switch (current_cpu_type()) {
1362 	case CPU_20KC:
1363 	case CPU_25KF:
1364 	case CPU_I6400:
1365 	case CPU_I6500:
1366 	case CPU_SB1:
1367 	case CPU_SB1A:
1368 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1369 		break;
1370 
1371 	case CPU_R10000:
1372 	case CPU_R12000:
1373 	case CPU_R14000:
1374 	case CPU_R16000:
1375 		break;
1376 
1377 	case CPU_74K:
1378 	case CPU_1074K:
1379 		has_74k_erratum = alias_74k_erratum(c);
1380 		fallthrough;
1381 	case CPU_M14KC:
1382 	case CPU_M14KEC:
1383 	case CPU_24K:
1384 	case CPU_34K:
1385 	case CPU_1004K:
1386 	case CPU_INTERAPTIV:
1387 	case CPU_P5600:
1388 	case CPU_PROAPTIV:
1389 	case CPU_M5150:
1390 	case CPU_QEMU_GENERIC:
1391 	case CPU_P6600:
1392 	case CPU_M6250:
1393 		if (!(read_c0_config7() & MIPS_CONF7_IAR) &&
1394 		    (c->icache.waysize > PAGE_SIZE))
1395 			c->icache.flags |= MIPS_CACHE_ALIASES;
1396 		if (!has_74k_erratum && (read_c0_config7() & MIPS_CONF7_AR)) {
1397 			/*
1398 			 * Effectively physically indexed dcache,
1399 			 * thus no virtual aliases.
1400 			*/
1401 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1402 			break;
1403 		}
1404 		fallthrough;
1405 	default:
1406 		if (has_74k_erratum || c->dcache.waysize > PAGE_SIZE)
1407 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1408 	}
1409 
1410 	/* Physically indexed caches don't suffer from virtual aliasing */
1411 	if (c->dcache.flags & MIPS_CACHE_PINDEX)
1412 		c->dcache.flags &= ~MIPS_CACHE_ALIASES;
1413 
1414 	/*
1415 	 * In systems with CM the icache fills from L2 or closer caches, and
1416 	 * thus sees remote stores without needing to write them back any
1417 	 * further than that.
1418 	 */
1419 	if (mips_cm_present())
1420 		c->icache.flags |= MIPS_IC_SNOOPS_REMOTE;
1421 
1422 	switch (current_cpu_type()) {
1423 	case CPU_20KC:
1424 		/*
1425 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1426 		 * the config register.
1427 		 */
1428 		c->icache.flags |= MIPS_CACHE_VTAG;
1429 		break;
1430 
1431 	case CPU_ALCHEMY:
1432 	case CPU_I6400:
1433 	case CPU_I6500:
1434 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1435 		break;
1436 
1437 	case CPU_BMIPS5000:
1438 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1439 		/* Cache aliases are handled in hardware; allow HIGHMEM */
1440 		c->dcache.flags &= ~MIPS_CACHE_ALIASES;
1441 		break;
1442 
1443 	case CPU_LOONGSON2EF:
1444 		/*
1445 		 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1446 		 * one op will act on all 4 ways
1447 		 */
1448 		c->icache.ways = 1;
1449 	}
1450 
1451 	pr_info("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1452 		icache_size >> 10,
1453 		c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1454 		way_string[c->icache.ways], c->icache.linesz);
1455 
1456 	pr_info("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1457 		dcache_size >> 10, way_string[c->dcache.ways],
1458 		(c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1459 		(c->dcache.flags & MIPS_CACHE_ALIASES) ?
1460 			"cache aliases" : "no aliases",
1461 		c->dcache.linesz);
1462 }
1463 
1464 static void probe_vcache(void)
1465 {
1466 	struct cpuinfo_mips *c = &current_cpu_data;
1467 	unsigned int config2, lsize;
1468 
1469 	if (current_cpu_type() != CPU_LOONGSON64)
1470 		return;
1471 
1472 	config2 = read_c0_config2();
1473 	if ((lsize = ((config2 >> 20) & 15)))
1474 		c->vcache.linesz = 2 << lsize;
1475 	else
1476 		c->vcache.linesz = lsize;
1477 
1478 	c->vcache.sets = 64 << ((config2 >> 24) & 15);
1479 	c->vcache.ways = 1 + ((config2 >> 16) & 15);
1480 
1481 	vcache_size = c->vcache.sets * c->vcache.ways * c->vcache.linesz;
1482 
1483 	c->vcache.waybit = 0;
1484 	c->vcache.waysize = vcache_size / c->vcache.ways;
1485 
1486 	pr_info("Unified victim cache %ldkB %s, linesize %d bytes.\n",
1487 		vcache_size >> 10, way_string[c->vcache.ways], c->vcache.linesz);
1488 }
1489 
1490 /*
1491  * If you even _breathe_ on this function, look at the gcc output and make sure
1492  * it does not pop things on and off the stack for the cache sizing loop that
1493  * executes in KSEG1 space or else you will crash and burn badly.  You have
1494  * been warned.
1495  */
1496 static int probe_scache(void)
1497 {
1498 	unsigned long flags, addr, begin, end, pow2;
1499 	unsigned int config = read_c0_config();
1500 	struct cpuinfo_mips *c = &current_cpu_data;
1501 
1502 	if (config & CONF_SC)
1503 		return 0;
1504 
1505 	begin = (unsigned long) &_stext;
1506 	begin &= ~((4 * 1024 * 1024) - 1);
1507 	end = begin + (4 * 1024 * 1024);
1508 
1509 	/*
1510 	 * This is such a bitch, you'd think they would make it easy to do
1511 	 * this.  Away you daemons of stupidity!
1512 	 */
1513 	local_irq_save(flags);
1514 
1515 	/* Fill each size-multiple cache line with a valid tag. */
1516 	pow2 = (64 * 1024);
1517 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1518 		unsigned long *p = (unsigned long *) addr;
1519 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1520 		pow2 <<= 1;
1521 	}
1522 
1523 	/* Load first line with zero (therefore invalid) tag. */
1524 	write_c0_taglo(0);
1525 	write_c0_taghi(0);
1526 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1527 	cache_op(Index_Store_Tag_I, begin);
1528 	cache_op(Index_Store_Tag_D, begin);
1529 	cache_op(Index_Store_Tag_SD, begin);
1530 
1531 	/* Now search for the wrap around point. */
1532 	pow2 = (128 * 1024);
1533 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1534 		cache_op(Index_Load_Tag_SD, addr);
1535 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1536 		if (!read_c0_taglo())
1537 			break;
1538 		pow2 <<= 1;
1539 	}
1540 	local_irq_restore(flags);
1541 	addr -= begin;
1542 
1543 	scache_size = addr;
1544 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1545 	c->scache.ways = 1;
1546 	c->scache.waybit = 0;		/* does not matter */
1547 
1548 	return 1;
1549 }
1550 
1551 static void loongson2_sc_init(void)
1552 {
1553 	struct cpuinfo_mips *c = &current_cpu_data;
1554 
1555 	scache_size = 512*1024;
1556 	c->scache.linesz = 32;
1557 	c->scache.ways = 4;
1558 	c->scache.waybit = 0;
1559 	c->scache.waysize = scache_size / (c->scache.ways);
1560 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1561 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1562 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1563 
1564 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1565 }
1566 
1567 static void loongson3_sc_init(void)
1568 {
1569 	struct cpuinfo_mips *c = &current_cpu_data;
1570 	unsigned int config2, lsize;
1571 
1572 	config2 = read_c0_config2();
1573 	lsize = (config2 >> 4) & 15;
1574 	if (lsize)
1575 		c->scache.linesz = 2 << lsize;
1576 	else
1577 		c->scache.linesz = 0;
1578 	c->scache.sets = 64 << ((config2 >> 8) & 15);
1579 	c->scache.ways = 1 + (config2 & 15);
1580 
1581 	/* Loongson-3 has 4-Scache banks, while Loongson-2K have only 2 banks */
1582 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_LOONGSON_64R)
1583 		c->scache.sets *= 2;
1584 	else
1585 		c->scache.sets *= 4;
1586 
1587 	scache_size = c->scache.sets * c->scache.ways * c->scache.linesz;
1588 
1589 	c->scache.waybit = 0;
1590 	c->scache.waysize = scache_size / c->scache.ways;
1591 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1592 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1593 	if (scache_size)
1594 		c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1595 	return;
1596 }
1597 
1598 extern int r5k_sc_init(void);
1599 extern int rm7k_sc_init(void);
1600 extern int mips_sc_init(void);
1601 
1602 static void setup_scache(void)
1603 {
1604 	struct cpuinfo_mips *c = &current_cpu_data;
1605 	unsigned int config = read_c0_config();
1606 	int sc_present = 0;
1607 
1608 	/*
1609 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1610 	 * processors don't have a S-cache that would be relevant to the
1611 	 * Linux memory management.
1612 	 */
1613 	switch (current_cpu_type()) {
1614 	case CPU_R4000SC:
1615 	case CPU_R4000MC:
1616 	case CPU_R4400SC:
1617 	case CPU_R4400MC:
1618 		sc_present = run_uncached(probe_scache);
1619 		if (sc_present)
1620 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1621 		break;
1622 
1623 	case CPU_R10000:
1624 	case CPU_R12000:
1625 	case CPU_R14000:
1626 	case CPU_R16000:
1627 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1628 		c->scache.linesz = 64 << ((config >> 13) & 1);
1629 		c->scache.ways = 2;
1630 		c->scache.waybit= 0;
1631 		sc_present = 1;
1632 		break;
1633 
1634 	case CPU_R5000:
1635 	case CPU_NEVADA:
1636 #ifdef CONFIG_R5000_CPU_SCACHE
1637 		r5k_sc_init();
1638 #endif
1639 		return;
1640 
1641 	case CPU_RM7000:
1642 #ifdef CONFIG_RM7000_CPU_SCACHE
1643 		rm7k_sc_init();
1644 #endif
1645 		return;
1646 
1647 	case CPU_LOONGSON2EF:
1648 		loongson2_sc_init();
1649 		return;
1650 
1651 	case CPU_LOONGSON64:
1652 		loongson3_sc_init();
1653 		return;
1654 
1655 	case CPU_CAVIUM_OCTEON3:
1656 		/* don't need to worry about L2, fully coherent */
1657 		return;
1658 
1659 	default:
1660 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
1661 				    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
1662 				    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
1663 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
1664 #ifdef CONFIG_MIPS_CPU_SCACHE
1665 			if (mips_sc_init ()) {
1666 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1667 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1668 				       scache_size >> 10,
1669 				       way_string[c->scache.ways], c->scache.linesz);
1670 
1671 				if (current_cpu_type() == CPU_BMIPS5000)
1672 					c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1673 			}
1674 
1675 #else
1676 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1677 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1678 #endif
1679 			return;
1680 		}
1681 		sc_present = 0;
1682 	}
1683 
1684 	if (!sc_present)
1685 		return;
1686 
1687 	/* compute a couple of other cache variables */
1688 	c->scache.waysize = scache_size / c->scache.ways;
1689 
1690 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1691 
1692 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1693 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1694 
1695 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1696 }
1697 
1698 void au1x00_fixup_config_od(void)
1699 {
1700 	/*
1701 	 * c0_config.od (bit 19) was write only (and read as 0)
1702 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1703 	 * transaction overlapping and needs to be set to fix various errata.
1704 	 */
1705 	switch (read_c0_prid()) {
1706 	case 0x00030100: /* Au1000 DA */
1707 	case 0x00030201: /* Au1000 HA */
1708 	case 0x00030202: /* Au1000 HB */
1709 	case 0x01030200: /* Au1500 AB */
1710 	/*
1711 	 * Au1100 errata actually keeps silence about this bit, so we set it
1712 	 * just in case for those revisions that require it to be set according
1713 	 * to the (now gone) cpu table.
1714 	 */
1715 	case 0x02030200: /* Au1100 AB */
1716 	case 0x02030201: /* Au1100 BA */
1717 	case 0x02030202: /* Au1100 BC */
1718 		set_c0_config(1 << 19);
1719 		break;
1720 	}
1721 }
1722 
1723 /* CP0 hazard avoidance. */
1724 #define NXP_BARRIER()							\
1725 	 __asm__ __volatile__(						\
1726 	".set noreorder\n\t"						\
1727 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1728 	".set reorder\n\t")
1729 
1730 static void nxp_pr4450_fixup_config(void)
1731 {
1732 	unsigned long config0;
1733 
1734 	config0 = read_c0_config();
1735 
1736 	/* clear all three cache coherency fields */
1737 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1738 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1739 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1740 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1741 	write_c0_config(config0);
1742 	NXP_BARRIER();
1743 }
1744 
1745 static int cca = -1;
1746 
1747 static int __init cca_setup(char *str)
1748 {
1749 	get_option(&str, &cca);
1750 
1751 	return 0;
1752 }
1753 
1754 early_param("cca", cca_setup);
1755 
1756 static void coherency_setup(void)
1757 {
1758 	if (cca < 0 || cca > 7)
1759 		cca = read_c0_config() & CONF_CM_CMASK;
1760 	_page_cachable_default = cca << _CACHE_SHIFT;
1761 
1762 	pr_debug("Using cache attribute %d\n", cca);
1763 	change_c0_config(CONF_CM_CMASK, cca);
1764 
1765 	/*
1766 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1767 	 * the coherency mode specified by the TLB; 1 means cachable
1768 	 * coherent update on write will be used.  Not all processors have
1769 	 * this bit and; some wire it to zero, others like Toshiba had the
1770 	 * silly idea of putting something else there ...
1771 	 */
1772 	switch (current_cpu_type()) {
1773 	case CPU_R4000PC:
1774 	case CPU_R4000SC:
1775 	case CPU_R4000MC:
1776 	case CPU_R4400PC:
1777 	case CPU_R4400SC:
1778 	case CPU_R4400MC:
1779 		clear_c0_config(CONF_CU);
1780 		break;
1781 	/*
1782 	 * We need to catch the early Alchemy SOCs with
1783 	 * the write-only co_config.od bit and set it back to one on:
1784 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1785 	 */
1786 	case CPU_ALCHEMY:
1787 		au1x00_fixup_config_od();
1788 		break;
1789 
1790 	case PRID_IMP_PR4450:
1791 		nxp_pr4450_fixup_config();
1792 		break;
1793 	}
1794 }
1795 
1796 static void r4k_cache_error_setup(void)
1797 {
1798 	extern char __weak except_vec2_generic;
1799 	extern char __weak except_vec2_sb1;
1800 
1801 	switch (current_cpu_type()) {
1802 	case CPU_SB1:
1803 	case CPU_SB1A:
1804 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1805 		break;
1806 
1807 	default:
1808 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1809 		break;
1810 	}
1811 }
1812 
1813 void r4k_cache_init(void)
1814 {
1815 	extern void build_clear_page(void);
1816 	extern void build_copy_page(void);
1817 	struct cpuinfo_mips *c = &current_cpu_data;
1818 
1819 	probe_pcache();
1820 	probe_vcache();
1821 	setup_scache();
1822 
1823 	r4k_blast_dcache_page_setup();
1824 	r4k_blast_dcache_page_indexed_setup();
1825 	r4k_blast_dcache_setup();
1826 	r4k_blast_icache_page_setup();
1827 	r4k_blast_icache_page_indexed_setup();
1828 	r4k_blast_icache_setup();
1829 	r4k_blast_scache_page_setup();
1830 	r4k_blast_scache_page_indexed_setup();
1831 	r4k_blast_scache_setup();
1832 	r4k_blast_scache_node_setup();
1833 #ifdef CONFIG_EVA
1834 	r4k_blast_dcache_user_page_setup();
1835 	r4k_blast_icache_user_page_setup();
1836 #endif
1837 
1838 	/*
1839 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1840 	 * This code supports virtually indexed processors and will be
1841 	 * unnecessarily inefficient on physically indexed processors.
1842 	 */
1843 	if (c->dcache.linesz && cpu_has_dc_aliases)
1844 		shm_align_mask = max_t( unsigned long,
1845 					c->dcache.sets * c->dcache.linesz - 1,
1846 					PAGE_SIZE - 1);
1847 	else
1848 		shm_align_mask = PAGE_SIZE-1;
1849 
1850 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1851 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1852 
1853 	flush_cache_all		= cache_noop;
1854 	__flush_cache_all	= r4k___flush_cache_all;
1855 	flush_cache_mm		= r4k_flush_cache_mm;
1856 	flush_cache_page	= r4k_flush_cache_page;
1857 	flush_cache_range	= r4k_flush_cache_range;
1858 
1859 	__flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1860 
1861 	flush_icache_all	= r4k_flush_icache_all;
1862 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1863 	flush_data_cache_page	= r4k_flush_data_cache_page;
1864 	flush_icache_range	= r4k_flush_icache_range;
1865 	local_flush_icache_range	= local_r4k_flush_icache_range;
1866 	__flush_icache_user_range	= r4k_flush_icache_user_range;
1867 	__local_flush_icache_user_range	= local_r4k_flush_icache_user_range;
1868 
1869 #ifdef CONFIG_DMA_NONCOHERENT
1870 	if (dma_default_coherent) {
1871 		_dma_cache_wback_inv	= (void *)cache_noop;
1872 		_dma_cache_wback	= (void *)cache_noop;
1873 		_dma_cache_inv		= (void *)cache_noop;
1874 	} else {
1875 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1876 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1877 		_dma_cache_inv		= r4k_dma_cache_inv;
1878 	}
1879 #endif /* CONFIG_DMA_NONCOHERENT */
1880 
1881 	build_clear_page();
1882 	build_copy_page();
1883 
1884 	/*
1885 	 * We want to run CMP kernels on core with and without coherent
1886 	 * caches. Therefore, do not use CONFIG_MIPS_CMP to decide whether
1887 	 * or not to flush caches.
1888 	 */
1889 	local_r4k___flush_cache_all(NULL);
1890 
1891 	coherency_setup();
1892 	board_cache_error_setup = r4k_cache_error_setup;
1893 
1894 	/*
1895 	 * Per-CPU overrides
1896 	 */
1897 	switch (current_cpu_type()) {
1898 	case CPU_BMIPS4350:
1899 	case CPU_BMIPS4380:
1900 		/* No IPI is needed because all CPUs share the same D$ */
1901 		flush_data_cache_page = r4k_blast_dcache_page;
1902 		break;
1903 	case CPU_BMIPS5000:
1904 		/* We lose our superpowers if L2 is disabled */
1905 		if (c->scache.flags & MIPS_CACHE_NOT_PRESENT)
1906 			break;
1907 
1908 		/* I$ fills from D$ just by emptying the write buffers */
1909 		flush_cache_page = (void *)b5k_instruction_hazard;
1910 		flush_cache_range = (void *)b5k_instruction_hazard;
1911 		local_flush_data_cache_page = (void *)b5k_instruction_hazard;
1912 		flush_data_cache_page = (void *)b5k_instruction_hazard;
1913 		flush_icache_range = (void *)b5k_instruction_hazard;
1914 		local_flush_icache_range = (void *)b5k_instruction_hazard;
1915 
1916 
1917 		/* Optimization: an L2 flush implicitly flushes the L1 */
1918 		current_cpu_data.options |= MIPS_CPU_INCLUSIVE_CACHES;
1919 		break;
1920 	case CPU_LOONGSON64:
1921 		/* Loongson-3 maintains cache coherency by hardware */
1922 		__flush_cache_all	= cache_noop;
1923 		__flush_cache_vmap	= cache_noop;
1924 		__flush_cache_vunmap	= cache_noop;
1925 		__flush_kernel_vmap_range = (void *)cache_noop;
1926 		flush_cache_mm		= (void *)cache_noop;
1927 		flush_cache_page	= (void *)cache_noop;
1928 		flush_cache_range	= (void *)cache_noop;
1929 		flush_icache_all	= (void *)cache_noop;
1930 		flush_data_cache_page	= (void *)cache_noop;
1931 		local_flush_data_cache_page	= (void *)cache_noop;
1932 		break;
1933 	}
1934 }
1935 
1936 static int r4k_cache_pm_notifier(struct notifier_block *self, unsigned long cmd,
1937 			       void *v)
1938 {
1939 	switch (cmd) {
1940 	case CPU_PM_ENTER_FAILED:
1941 	case CPU_PM_EXIT:
1942 		coherency_setup();
1943 		break;
1944 	}
1945 
1946 	return NOTIFY_OK;
1947 }
1948 
1949 static struct notifier_block r4k_cache_pm_notifier_block = {
1950 	.notifier_call = r4k_cache_pm_notifier,
1951 };
1952 
1953 int __init r4k_cache_init_pm(void)
1954 {
1955 	return cpu_pm_register_notifier(&r4k_cache_pm_notifier_block);
1956 }
1957 arch_initcall(r4k_cache_init_pm);
1958