xref: /openbmc/linux/arch/mips/mm/c-r4k.c (revision a09d2831)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
7  * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  */
10 #include <linux/hardirq.h>
11 #include <linux/init.h>
12 #include <linux/highmem.h>
13 #include <linux/kernel.h>
14 #include <linux/linkage.h>
15 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/mm.h>
18 #include <linux/module.h>
19 #include <linux/bitops.h>
20 
21 #include <asm/bcache.h>
22 #include <asm/bootinfo.h>
23 #include <asm/cache.h>
24 #include <asm/cacheops.h>
25 #include <asm/cpu.h>
26 #include <asm/cpu-features.h>
27 #include <asm/io.h>
28 #include <asm/page.h>
29 #include <asm/pgtable.h>
30 #include <asm/r4kcache.h>
31 #include <asm/sections.h>
32 #include <asm/system.h>
33 #include <asm/mmu_context.h>
34 #include <asm/war.h>
35 #include <asm/cacheflush.h> /* for run_uncached() */
36 
37 
38 /*
39  * Special Variant of smp_call_function for use by cache functions:
40  *
41  *  o No return value
42  *  o collapses to normal function call on UP kernels
43  *  o collapses to normal function call on systems with a single shared
44  *    primary cache.
45  */
46 static inline void r4k_on_each_cpu(void (*func) (void *info), void *info,
47                                    int wait)
48 {
49 	preempt_disable();
50 
51 #if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
52 	smp_call_function(func, info, wait);
53 #endif
54 	func(info);
55 	preempt_enable();
56 }
57 
58 #if defined(CONFIG_MIPS_CMP)
59 #define cpu_has_safe_index_cacheops 0
60 #else
61 #define cpu_has_safe_index_cacheops 1
62 #endif
63 
64 /*
65  * Must die.
66  */
67 static unsigned long icache_size __read_mostly;
68 static unsigned long dcache_size __read_mostly;
69 static unsigned long scache_size __read_mostly;
70 
71 /*
72  * Dummy cache handling routines for machines without boardcaches
73  */
74 static void cache_noop(void) {}
75 
76 static struct bcache_ops no_sc_ops = {
77 	.bc_enable = (void *)cache_noop,
78 	.bc_disable = (void *)cache_noop,
79 	.bc_wback_inv = (void *)cache_noop,
80 	.bc_inv = (void *)cache_noop
81 };
82 
83 struct bcache_ops *bcops = &no_sc_ops;
84 
85 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
86 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
87 
88 #define R4600_HIT_CACHEOP_WAR_IMPL					\
89 do {									\
90 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
91 		*(volatile unsigned long *)CKSEG1;			\
92 	if (R4600_V1_HIT_CACHEOP_WAR)					\
93 		__asm__ __volatile__("nop;nop;nop;nop");		\
94 } while (0)
95 
96 static void (*r4k_blast_dcache_page)(unsigned long addr);
97 
98 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
99 {
100 	R4600_HIT_CACHEOP_WAR_IMPL;
101 	blast_dcache32_page(addr);
102 }
103 
104 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
105 {
106 	R4600_HIT_CACHEOP_WAR_IMPL;
107 	blast_dcache64_page(addr);
108 }
109 
110 static void __cpuinit r4k_blast_dcache_page_setup(void)
111 {
112 	unsigned long  dc_lsize = cpu_dcache_line_size();
113 
114 	if (dc_lsize == 0)
115 		r4k_blast_dcache_page = (void *)cache_noop;
116 	else if (dc_lsize == 16)
117 		r4k_blast_dcache_page = blast_dcache16_page;
118 	else if (dc_lsize == 32)
119 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
120 	else if (dc_lsize == 64)
121 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
122 }
123 
124 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
125 
126 static void __cpuinit r4k_blast_dcache_page_indexed_setup(void)
127 {
128 	unsigned long dc_lsize = cpu_dcache_line_size();
129 
130 	if (dc_lsize == 0)
131 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
132 	else if (dc_lsize == 16)
133 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
134 	else if (dc_lsize == 32)
135 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
136 	else if (dc_lsize == 64)
137 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
138 }
139 
140 static void (* r4k_blast_dcache)(void);
141 
142 static void __cpuinit r4k_blast_dcache_setup(void)
143 {
144 	unsigned long dc_lsize = cpu_dcache_line_size();
145 
146 	if (dc_lsize == 0)
147 		r4k_blast_dcache = (void *)cache_noop;
148 	else if (dc_lsize == 16)
149 		r4k_blast_dcache = blast_dcache16;
150 	else if (dc_lsize == 32)
151 		r4k_blast_dcache = blast_dcache32;
152 	else if (dc_lsize == 64)
153 		r4k_blast_dcache = blast_dcache64;
154 }
155 
156 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
157 #define JUMP_TO_ALIGN(order) \
158 	__asm__ __volatile__( \
159 		"b\t1f\n\t" \
160 		".align\t" #order "\n\t" \
161 		"1:\n\t" \
162 		)
163 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
164 #define CACHE32_UNROLL32_ALIGN2	JUMP_TO_ALIGN(11)
165 
166 static inline void blast_r4600_v1_icache32(void)
167 {
168 	unsigned long flags;
169 
170 	local_irq_save(flags);
171 	blast_icache32();
172 	local_irq_restore(flags);
173 }
174 
175 static inline void tx49_blast_icache32(void)
176 {
177 	unsigned long start = INDEX_BASE;
178 	unsigned long end = start + current_cpu_data.icache.waysize;
179 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
180 	unsigned long ws_end = current_cpu_data.icache.ways <<
181 	                       current_cpu_data.icache.waybit;
182 	unsigned long ws, addr;
183 
184 	CACHE32_UNROLL32_ALIGN2;
185 	/* I'm in even chunk.  blast odd chunks */
186 	for (ws = 0; ws < ws_end; ws += ws_inc)
187 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
188 			cache32_unroll32(addr|ws, Index_Invalidate_I);
189 	CACHE32_UNROLL32_ALIGN;
190 	/* I'm in odd chunk.  blast even chunks */
191 	for (ws = 0; ws < ws_end; ws += ws_inc)
192 		for (addr = start; addr < end; addr += 0x400 * 2)
193 			cache32_unroll32(addr|ws, Index_Invalidate_I);
194 }
195 
196 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
197 {
198 	unsigned long flags;
199 
200 	local_irq_save(flags);
201 	blast_icache32_page_indexed(page);
202 	local_irq_restore(flags);
203 }
204 
205 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
206 {
207 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
208 	unsigned long start = INDEX_BASE + (page & indexmask);
209 	unsigned long end = start + PAGE_SIZE;
210 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
211 	unsigned long ws_end = current_cpu_data.icache.ways <<
212 	                       current_cpu_data.icache.waybit;
213 	unsigned long ws, addr;
214 
215 	CACHE32_UNROLL32_ALIGN2;
216 	/* I'm in even chunk.  blast odd chunks */
217 	for (ws = 0; ws < ws_end; ws += ws_inc)
218 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
219 			cache32_unroll32(addr|ws, Index_Invalidate_I);
220 	CACHE32_UNROLL32_ALIGN;
221 	/* I'm in odd chunk.  blast even chunks */
222 	for (ws = 0; ws < ws_end; ws += ws_inc)
223 		for (addr = start; addr < end; addr += 0x400 * 2)
224 			cache32_unroll32(addr|ws, Index_Invalidate_I);
225 }
226 
227 static void (* r4k_blast_icache_page)(unsigned long addr);
228 
229 static void __cpuinit r4k_blast_icache_page_setup(void)
230 {
231 	unsigned long ic_lsize = cpu_icache_line_size();
232 
233 	if (ic_lsize == 0)
234 		r4k_blast_icache_page = (void *)cache_noop;
235 	else if (ic_lsize == 16)
236 		r4k_blast_icache_page = blast_icache16_page;
237 	else if (ic_lsize == 32)
238 		r4k_blast_icache_page = blast_icache32_page;
239 	else if (ic_lsize == 64)
240 		r4k_blast_icache_page = blast_icache64_page;
241 }
242 
243 
244 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
245 
246 static void __cpuinit r4k_blast_icache_page_indexed_setup(void)
247 {
248 	unsigned long ic_lsize = cpu_icache_line_size();
249 
250 	if (ic_lsize == 0)
251 		r4k_blast_icache_page_indexed = (void *)cache_noop;
252 	else if (ic_lsize == 16)
253 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
254 	else if (ic_lsize == 32) {
255 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
256 			r4k_blast_icache_page_indexed =
257 				blast_icache32_r4600_v1_page_indexed;
258 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
259 			r4k_blast_icache_page_indexed =
260 				tx49_blast_icache32_page_indexed;
261 		else
262 			r4k_blast_icache_page_indexed =
263 				blast_icache32_page_indexed;
264 	} else if (ic_lsize == 64)
265 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
266 }
267 
268 static void (* r4k_blast_icache)(void);
269 
270 static void __cpuinit r4k_blast_icache_setup(void)
271 {
272 	unsigned long ic_lsize = cpu_icache_line_size();
273 
274 	if (ic_lsize == 0)
275 		r4k_blast_icache = (void *)cache_noop;
276 	else if (ic_lsize == 16)
277 		r4k_blast_icache = blast_icache16;
278 	else if (ic_lsize == 32) {
279 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
280 			r4k_blast_icache = blast_r4600_v1_icache32;
281 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
282 			r4k_blast_icache = tx49_blast_icache32;
283 		else
284 			r4k_blast_icache = blast_icache32;
285 	} else if (ic_lsize == 64)
286 		r4k_blast_icache = blast_icache64;
287 }
288 
289 static void (* r4k_blast_scache_page)(unsigned long addr);
290 
291 static void __cpuinit r4k_blast_scache_page_setup(void)
292 {
293 	unsigned long sc_lsize = cpu_scache_line_size();
294 
295 	if (scache_size == 0)
296 		r4k_blast_scache_page = (void *)cache_noop;
297 	else if (sc_lsize == 16)
298 		r4k_blast_scache_page = blast_scache16_page;
299 	else if (sc_lsize == 32)
300 		r4k_blast_scache_page = blast_scache32_page;
301 	else if (sc_lsize == 64)
302 		r4k_blast_scache_page = blast_scache64_page;
303 	else if (sc_lsize == 128)
304 		r4k_blast_scache_page = blast_scache128_page;
305 }
306 
307 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
308 
309 static void __cpuinit r4k_blast_scache_page_indexed_setup(void)
310 {
311 	unsigned long sc_lsize = cpu_scache_line_size();
312 
313 	if (scache_size == 0)
314 		r4k_blast_scache_page_indexed = (void *)cache_noop;
315 	else if (sc_lsize == 16)
316 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
317 	else if (sc_lsize == 32)
318 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
319 	else if (sc_lsize == 64)
320 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
321 	else if (sc_lsize == 128)
322 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
323 }
324 
325 static void (* r4k_blast_scache)(void);
326 
327 static void __cpuinit r4k_blast_scache_setup(void)
328 {
329 	unsigned long sc_lsize = cpu_scache_line_size();
330 
331 	if (scache_size == 0)
332 		r4k_blast_scache = (void *)cache_noop;
333 	else if (sc_lsize == 16)
334 		r4k_blast_scache = blast_scache16;
335 	else if (sc_lsize == 32)
336 		r4k_blast_scache = blast_scache32;
337 	else if (sc_lsize == 64)
338 		r4k_blast_scache = blast_scache64;
339 	else if (sc_lsize == 128)
340 		r4k_blast_scache = blast_scache128;
341 }
342 
343 static inline void local_r4k___flush_cache_all(void * args)
344 {
345 #if defined(CONFIG_CPU_LOONGSON2)
346 	r4k_blast_scache();
347 	return;
348 #endif
349 	r4k_blast_dcache();
350 	r4k_blast_icache();
351 
352 	switch (current_cpu_type()) {
353 	case CPU_R4000SC:
354 	case CPU_R4000MC:
355 	case CPU_R4400SC:
356 	case CPU_R4400MC:
357 	case CPU_R10000:
358 	case CPU_R12000:
359 	case CPU_R14000:
360 		r4k_blast_scache();
361 	}
362 }
363 
364 static void r4k___flush_cache_all(void)
365 {
366 	r4k_on_each_cpu(local_r4k___flush_cache_all, NULL, 1);
367 }
368 
369 static inline int has_valid_asid(const struct mm_struct *mm)
370 {
371 #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
372 	int i;
373 
374 	for_each_online_cpu(i)
375 		if (cpu_context(i, mm))
376 			return 1;
377 
378 	return 0;
379 #else
380 	return cpu_context(smp_processor_id(), mm);
381 #endif
382 }
383 
384 static void r4k__flush_cache_vmap(void)
385 {
386 	r4k_blast_dcache();
387 }
388 
389 static void r4k__flush_cache_vunmap(void)
390 {
391 	r4k_blast_dcache();
392 }
393 
394 static inline void local_r4k_flush_cache_range(void * args)
395 {
396 	struct vm_area_struct *vma = args;
397 	int exec = vma->vm_flags & VM_EXEC;
398 
399 	if (!(has_valid_asid(vma->vm_mm)))
400 		return;
401 
402 	r4k_blast_dcache();
403 	if (exec)
404 		r4k_blast_icache();
405 }
406 
407 static void r4k_flush_cache_range(struct vm_area_struct *vma,
408 	unsigned long start, unsigned long end)
409 {
410 	int exec = vma->vm_flags & VM_EXEC;
411 
412 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
413 		r4k_on_each_cpu(local_r4k_flush_cache_range, vma, 1);
414 }
415 
416 static inline void local_r4k_flush_cache_mm(void * args)
417 {
418 	struct mm_struct *mm = args;
419 
420 	if (!has_valid_asid(mm))
421 		return;
422 
423 	/*
424 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
425 	 * only flush the primary caches but R10000 and R12000 behave sane ...
426 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
427 	 * caches, so we can bail out early.
428 	 */
429 	if (current_cpu_type() == CPU_R4000SC ||
430 	    current_cpu_type() == CPU_R4000MC ||
431 	    current_cpu_type() == CPU_R4400SC ||
432 	    current_cpu_type() == CPU_R4400MC) {
433 		r4k_blast_scache();
434 		return;
435 	}
436 
437 	r4k_blast_dcache();
438 }
439 
440 static void r4k_flush_cache_mm(struct mm_struct *mm)
441 {
442 	if (!cpu_has_dc_aliases)
443 		return;
444 
445 	r4k_on_each_cpu(local_r4k_flush_cache_mm, mm, 1);
446 }
447 
448 struct flush_cache_page_args {
449 	struct vm_area_struct *vma;
450 	unsigned long addr;
451 	unsigned long pfn;
452 };
453 
454 static inline void local_r4k_flush_cache_page(void *args)
455 {
456 	struct flush_cache_page_args *fcp_args = args;
457 	struct vm_area_struct *vma = fcp_args->vma;
458 	unsigned long addr = fcp_args->addr;
459 	struct page *page = pfn_to_page(fcp_args->pfn);
460 	int exec = vma->vm_flags & VM_EXEC;
461 	struct mm_struct *mm = vma->vm_mm;
462 	int map_coherent = 0;
463 	pgd_t *pgdp;
464 	pud_t *pudp;
465 	pmd_t *pmdp;
466 	pte_t *ptep;
467 	void *vaddr;
468 
469 	/*
470 	 * If ownes no valid ASID yet, cannot possibly have gotten
471 	 * this page into the cache.
472 	 */
473 	if (!has_valid_asid(mm))
474 		return;
475 
476 	addr &= PAGE_MASK;
477 	pgdp = pgd_offset(mm, addr);
478 	pudp = pud_offset(pgdp, addr);
479 	pmdp = pmd_offset(pudp, addr);
480 	ptep = pte_offset(pmdp, addr);
481 
482 	/*
483 	 * If the page isn't marked valid, the page cannot possibly be
484 	 * in the cache.
485 	 */
486 	if (!(pte_present(*ptep)))
487 		return;
488 
489 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
490 		vaddr = NULL;
491 	else {
492 		/*
493 		 * Use kmap_coherent or kmap_atomic to do flushes for
494 		 * another ASID than the current one.
495 		 */
496 		map_coherent = (cpu_has_dc_aliases &&
497 				page_mapped(page) && !Page_dcache_dirty(page));
498 		if (map_coherent)
499 			vaddr = kmap_coherent(page, addr);
500 		else
501 			vaddr = kmap_atomic(page, KM_USER0);
502 		addr = (unsigned long)vaddr;
503 	}
504 
505 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
506 		r4k_blast_dcache_page(addr);
507 		if (exec && !cpu_icache_snoops_remote_store)
508 			r4k_blast_scache_page(addr);
509 	}
510 	if (exec) {
511 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
512 			int cpu = smp_processor_id();
513 
514 			if (cpu_context(cpu, mm) != 0)
515 				drop_mmu_context(mm, cpu);
516 		} else
517 			r4k_blast_icache_page(addr);
518 	}
519 
520 	if (vaddr) {
521 		if (map_coherent)
522 			kunmap_coherent();
523 		else
524 			kunmap_atomic(vaddr, KM_USER0);
525 	}
526 }
527 
528 static void r4k_flush_cache_page(struct vm_area_struct *vma,
529 	unsigned long addr, unsigned long pfn)
530 {
531 	struct flush_cache_page_args args;
532 
533 	args.vma = vma;
534 	args.addr = addr;
535 	args.pfn = pfn;
536 
537 	r4k_on_each_cpu(local_r4k_flush_cache_page, &args, 1);
538 }
539 
540 static inline void local_r4k_flush_data_cache_page(void * addr)
541 {
542 	r4k_blast_dcache_page((unsigned long) addr);
543 }
544 
545 static void r4k_flush_data_cache_page(unsigned long addr)
546 {
547 	if (in_atomic())
548 		local_r4k_flush_data_cache_page((void *)addr);
549 	else
550 		r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr,
551 			        1);
552 }
553 
554 struct flush_icache_range_args {
555 	unsigned long start;
556 	unsigned long end;
557 };
558 
559 static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
560 {
561 	if (!cpu_has_ic_fills_f_dc) {
562 		if (end - start >= dcache_size) {
563 			r4k_blast_dcache();
564 		} else {
565 			R4600_HIT_CACHEOP_WAR_IMPL;
566 			protected_blast_dcache_range(start, end);
567 		}
568 	}
569 
570 	if (end - start > icache_size)
571 		r4k_blast_icache();
572 	else
573 		protected_blast_icache_range(start, end);
574 }
575 
576 static inline void local_r4k_flush_icache_range_ipi(void *args)
577 {
578 	struct flush_icache_range_args *fir_args = args;
579 	unsigned long start = fir_args->start;
580 	unsigned long end = fir_args->end;
581 
582 	local_r4k_flush_icache_range(start, end);
583 }
584 
585 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
586 {
587 	struct flush_icache_range_args args;
588 
589 	args.start = start;
590 	args.end = end;
591 
592 	r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args, 1);
593 	instruction_hazard();
594 }
595 
596 #ifdef CONFIG_DMA_NONCOHERENT
597 
598 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
599 {
600 	/* Catch bad driver code */
601 	BUG_ON(size == 0);
602 
603 	if (cpu_has_inclusive_pcaches) {
604 		if (size >= scache_size)
605 			r4k_blast_scache();
606 		else
607 			blast_scache_range(addr, addr + size);
608 		return;
609 	}
610 
611 	/*
612 	 * Either no secondary cache or the available caches don't have the
613 	 * subset property so we have to flush the primary caches
614 	 * explicitly
615 	 */
616 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
617 		r4k_blast_dcache();
618 	} else {
619 		R4600_HIT_CACHEOP_WAR_IMPL;
620 		blast_dcache_range(addr, addr + size);
621 	}
622 
623 	bc_wback_inv(addr, size);
624 }
625 
626 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
627 {
628 	/* Catch bad driver code */
629 	BUG_ON(size == 0);
630 
631 	if (cpu_has_inclusive_pcaches) {
632 		if (size >= scache_size)
633 			r4k_blast_scache();
634 		else {
635 			unsigned long lsize = cpu_scache_line_size();
636 			unsigned long almask = ~(lsize - 1);
637 
638 			/*
639 			 * There is no clearly documented alignment requirement
640 			 * for the cache instruction on MIPS processors and
641 			 * some processors, among them the RM5200 and RM7000
642 			 * QED processors will throw an address error for cache
643 			 * hit ops with insufficient alignment.  Solved by
644 			 * aligning the address to cache line size.
645 			 */
646 			cache_op(Hit_Writeback_Inv_SD, addr & almask);
647 			cache_op(Hit_Writeback_Inv_SD,
648 				 (addr + size - 1) & almask);
649 			blast_inv_scache_range(addr, addr + size);
650 		}
651 		return;
652 	}
653 
654 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
655 		r4k_blast_dcache();
656 	} else {
657 		unsigned long lsize = cpu_dcache_line_size();
658 		unsigned long almask = ~(lsize - 1);
659 
660 		R4600_HIT_CACHEOP_WAR_IMPL;
661 		cache_op(Hit_Writeback_Inv_D, addr & almask);
662 		cache_op(Hit_Writeback_Inv_D, (addr + size - 1)  & almask);
663 		blast_inv_dcache_range(addr, addr + size);
664 	}
665 
666 	bc_inv(addr, size);
667 }
668 #endif /* CONFIG_DMA_NONCOHERENT */
669 
670 /*
671  * While we're protected against bad userland addresses we don't care
672  * very much about what happens in that case.  Usually a segmentation
673  * fault will dump the process later on anyway ...
674  */
675 static void local_r4k_flush_cache_sigtramp(void * arg)
676 {
677 	unsigned long ic_lsize = cpu_icache_line_size();
678 	unsigned long dc_lsize = cpu_dcache_line_size();
679 	unsigned long sc_lsize = cpu_scache_line_size();
680 	unsigned long addr = (unsigned long) arg;
681 
682 	R4600_HIT_CACHEOP_WAR_IMPL;
683 	if (dc_lsize)
684 		protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
685 	if (!cpu_icache_snoops_remote_store && scache_size)
686 		protected_writeback_scache_line(addr & ~(sc_lsize - 1));
687 	if (ic_lsize)
688 		protected_flush_icache_line(addr & ~(ic_lsize - 1));
689 	if (MIPS4K_ICACHE_REFILL_WAR) {
690 		__asm__ __volatile__ (
691 			".set push\n\t"
692 			".set noat\n\t"
693 			".set mips3\n\t"
694 #ifdef CONFIG_32BIT
695 			"la	$at,1f\n\t"
696 #endif
697 #ifdef CONFIG_64BIT
698 			"dla	$at,1f\n\t"
699 #endif
700 			"cache	%0,($at)\n\t"
701 			"nop; nop; nop\n"
702 			"1:\n\t"
703 			".set pop"
704 			:
705 			: "i" (Hit_Invalidate_I));
706 	}
707 	if (MIPS_CACHE_SYNC_WAR)
708 		__asm__ __volatile__ ("sync");
709 }
710 
711 static void r4k_flush_cache_sigtramp(unsigned long addr)
712 {
713 	r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr, 1);
714 }
715 
716 static void r4k_flush_icache_all(void)
717 {
718 	if (cpu_has_vtag_icache)
719 		r4k_blast_icache();
720 }
721 
722 static inline void rm7k_erratum31(void)
723 {
724 	const unsigned long ic_lsize = 32;
725 	unsigned long addr;
726 
727 	/* RM7000 erratum #31. The icache is screwed at startup. */
728 	write_c0_taglo(0);
729 	write_c0_taghi(0);
730 
731 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
732 		__asm__ __volatile__ (
733 			".set push\n\t"
734 			".set noreorder\n\t"
735 			".set mips3\n\t"
736 			"cache\t%1, 0(%0)\n\t"
737 			"cache\t%1, 0x1000(%0)\n\t"
738 			"cache\t%1, 0x2000(%0)\n\t"
739 			"cache\t%1, 0x3000(%0)\n\t"
740 			"cache\t%2, 0(%0)\n\t"
741 			"cache\t%2, 0x1000(%0)\n\t"
742 			"cache\t%2, 0x2000(%0)\n\t"
743 			"cache\t%2, 0x3000(%0)\n\t"
744 			"cache\t%1, 0(%0)\n\t"
745 			"cache\t%1, 0x1000(%0)\n\t"
746 			"cache\t%1, 0x2000(%0)\n\t"
747 			"cache\t%1, 0x3000(%0)\n\t"
748 			".set pop\n"
749 			:
750 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
751 	}
752 }
753 
754 static char *way_string[] __cpuinitdata = { NULL, "direct mapped", "2-way",
755 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
756 };
757 
758 static void __cpuinit probe_pcache(void)
759 {
760 	struct cpuinfo_mips *c = &current_cpu_data;
761 	unsigned int config = read_c0_config();
762 	unsigned int prid = read_c0_prid();
763 	unsigned long config1;
764 	unsigned int lsize;
765 
766 	switch (c->cputype) {
767 	case CPU_R4600:			/* QED style two way caches? */
768 	case CPU_R4700:
769 	case CPU_R5000:
770 	case CPU_NEVADA:
771 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
772 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
773 		c->icache.ways = 2;
774 		c->icache.waybit = __ffs(icache_size/2);
775 
776 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
777 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
778 		c->dcache.ways = 2;
779 		c->dcache.waybit= __ffs(dcache_size/2);
780 
781 		c->options |= MIPS_CPU_CACHE_CDEX_P;
782 		break;
783 
784 	case CPU_R5432:
785 	case CPU_R5500:
786 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
787 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
788 		c->icache.ways = 2;
789 		c->icache.waybit= 0;
790 
791 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
792 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
793 		c->dcache.ways = 2;
794 		c->dcache.waybit = 0;
795 
796 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
797 		break;
798 
799 	case CPU_TX49XX:
800 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
801 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
802 		c->icache.ways = 4;
803 		c->icache.waybit= 0;
804 
805 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
806 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
807 		c->dcache.ways = 4;
808 		c->dcache.waybit = 0;
809 
810 		c->options |= MIPS_CPU_CACHE_CDEX_P;
811 		c->options |= MIPS_CPU_PREFETCH;
812 		break;
813 
814 	case CPU_R4000PC:
815 	case CPU_R4000SC:
816 	case CPU_R4000MC:
817 	case CPU_R4400PC:
818 	case CPU_R4400SC:
819 	case CPU_R4400MC:
820 	case CPU_R4300:
821 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
822 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
823 		c->icache.ways = 1;
824 		c->icache.waybit = 0; 	/* doesn't matter */
825 
826 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
827 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
828 		c->dcache.ways = 1;
829 		c->dcache.waybit = 0;	/* does not matter */
830 
831 		c->options |= MIPS_CPU_CACHE_CDEX_P;
832 		break;
833 
834 	case CPU_R10000:
835 	case CPU_R12000:
836 	case CPU_R14000:
837 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
838 		c->icache.linesz = 64;
839 		c->icache.ways = 2;
840 		c->icache.waybit = 0;
841 
842 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
843 		c->dcache.linesz = 32;
844 		c->dcache.ways = 2;
845 		c->dcache.waybit = 0;
846 
847 		c->options |= MIPS_CPU_PREFETCH;
848 		break;
849 
850 	case CPU_VR4133:
851 		write_c0_config(config & ~VR41_CONF_P4K);
852 	case CPU_VR4131:
853 		/* Workaround for cache instruction bug of VR4131 */
854 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
855 		    c->processor_id == 0x0c82U) {
856 			config |= 0x00400000U;
857 			if (c->processor_id == 0x0c80U)
858 				config |= VR41_CONF_BP;
859 			write_c0_config(config);
860 		} else
861 			c->options |= MIPS_CPU_CACHE_CDEX_P;
862 
863 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
864 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
865 		c->icache.ways = 2;
866 		c->icache.waybit = __ffs(icache_size/2);
867 
868 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
869 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
870 		c->dcache.ways = 2;
871 		c->dcache.waybit = __ffs(dcache_size/2);
872 		break;
873 
874 	case CPU_VR41XX:
875 	case CPU_VR4111:
876 	case CPU_VR4121:
877 	case CPU_VR4122:
878 	case CPU_VR4181:
879 	case CPU_VR4181A:
880 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
881 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
882 		c->icache.ways = 1;
883 		c->icache.waybit = 0; 	/* doesn't matter */
884 
885 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
886 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
887 		c->dcache.ways = 1;
888 		c->dcache.waybit = 0;	/* does not matter */
889 
890 		c->options |= MIPS_CPU_CACHE_CDEX_P;
891 		break;
892 
893 	case CPU_RM7000:
894 		rm7k_erratum31();
895 
896 	case CPU_RM9000:
897 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
898 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
899 		c->icache.ways = 4;
900 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
901 
902 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
903 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
904 		c->dcache.ways = 4;
905 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
906 
907 #if !defined(CONFIG_SMP) || !defined(RM9000_CDEX_SMP_WAR)
908 		c->options |= MIPS_CPU_CACHE_CDEX_P;
909 #endif
910 		c->options |= MIPS_CPU_PREFETCH;
911 		break;
912 
913 	case CPU_LOONGSON2:
914 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
915 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
916 		if (prid & 0x3)
917 			c->icache.ways = 4;
918 		else
919 			c->icache.ways = 2;
920 		c->icache.waybit = 0;
921 
922 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
923 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
924 		if (prid & 0x3)
925 			c->dcache.ways = 4;
926 		else
927 			c->dcache.ways = 2;
928 		c->dcache.waybit = 0;
929 		break;
930 
931 	default:
932 		if (!(config & MIPS_CONF_M))
933 			panic("Don't know how to probe P-caches on this cpu.");
934 
935 		/*
936 		 * So we seem to be a MIPS32 or MIPS64 CPU
937 		 * So let's probe the I-cache ...
938 		 */
939 		config1 = read_c0_config1();
940 
941 		if ((lsize = ((config1 >> 19) & 7)))
942 			c->icache.linesz = 2 << lsize;
943 		else
944 			c->icache.linesz = lsize;
945 		c->icache.sets = 64 << ((config1 >> 22) & 7);
946 		c->icache.ways = 1 + ((config1 >> 16) & 7);
947 
948 		icache_size = c->icache.sets *
949 		              c->icache.ways *
950 		              c->icache.linesz;
951 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
952 
953 		if (config & 0x8)		/* VI bit */
954 			c->icache.flags |= MIPS_CACHE_VTAG;
955 
956 		/*
957 		 * Now probe the MIPS32 / MIPS64 data cache.
958 		 */
959 		c->dcache.flags = 0;
960 
961 		if ((lsize = ((config1 >> 10) & 7)))
962 			c->dcache.linesz = 2 << lsize;
963 		else
964 			c->dcache.linesz= lsize;
965 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
966 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
967 
968 		dcache_size = c->dcache.sets *
969 		              c->dcache.ways *
970 		              c->dcache.linesz;
971 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
972 
973 		c->options |= MIPS_CPU_PREFETCH;
974 		break;
975 	}
976 
977 	/*
978 	 * Processor configuration sanity check for the R4000SC erratum
979 	 * #5.  With page sizes larger than 32kB there is no possibility
980 	 * to get a VCE exception anymore so we don't care about this
981 	 * misconfiguration.  The case is rather theoretical anyway;
982 	 * presumably no vendor is shipping his hardware in the "bad"
983 	 * configuration.
984 	 */
985 	if ((prid & 0xff00) == PRID_IMP_R4000 && (prid & 0xff) < 0x40 &&
986 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
987 	    PAGE_SIZE <= 0x8000)
988 		panic("Improper R4000SC processor configuration detected");
989 
990 	/* compute a couple of other cache variables */
991 	c->icache.waysize = icache_size / c->icache.ways;
992 	c->dcache.waysize = dcache_size / c->dcache.ways;
993 
994 	c->icache.sets = c->icache.linesz ?
995 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
996 	c->dcache.sets = c->dcache.linesz ?
997 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
998 
999 	/*
1000 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
1001 	 * 2-way virtually indexed so normally would suffer from aliases.  So
1002 	 * normally they'd suffer from aliases but magic in the hardware deals
1003 	 * with that for us so we don't need to take care ourselves.
1004 	 */
1005 	switch (c->cputype) {
1006 	case CPU_20KC:
1007 	case CPU_25KF:
1008 	case CPU_SB1:
1009 	case CPU_SB1A:
1010 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1011 		break;
1012 
1013 	case CPU_R10000:
1014 	case CPU_R12000:
1015 	case CPU_R14000:
1016 		break;
1017 
1018 	case CPU_24K:
1019 	case CPU_34K:
1020 	case CPU_74K:
1021 	case CPU_1004K:
1022 		if ((read_c0_config7() & (1 << 16))) {
1023 			/* effectively physically indexed dcache,
1024 			   thus no virtual aliases. */
1025 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1026 			break;
1027 		}
1028 	default:
1029 		if (c->dcache.waysize > PAGE_SIZE)
1030 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1031 	}
1032 
1033 	switch (c->cputype) {
1034 	case CPU_20KC:
1035 		/*
1036 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1037 		 * the config register.
1038 		 */
1039 		c->icache.flags |= MIPS_CACHE_VTAG;
1040 		break;
1041 
1042 	case CPU_ALCHEMY:
1043 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1044 		break;
1045 	}
1046 
1047 #ifdef  CONFIG_CPU_LOONGSON2
1048 	/*
1049 	 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1050 	 * one op will act on all 4 ways
1051 	 */
1052 	c->icache.ways = 1;
1053 #endif
1054 
1055 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1056 	       icache_size >> 10,
1057 	       c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1058 	       way_string[c->icache.ways], c->icache.linesz);
1059 
1060 	printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1061 	       dcache_size >> 10, way_string[c->dcache.ways],
1062 	       (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1063 	       (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1064 			"cache aliases" : "no aliases",
1065 	       c->dcache.linesz);
1066 }
1067 
1068 /*
1069  * If you even _breathe_ on this function, look at the gcc output and make sure
1070  * it does not pop things on and off the stack for the cache sizing loop that
1071  * executes in KSEG1 space or else you will crash and burn badly.  You have
1072  * been warned.
1073  */
1074 static int __cpuinit probe_scache(void)
1075 {
1076 	unsigned long flags, addr, begin, end, pow2;
1077 	unsigned int config = read_c0_config();
1078 	struct cpuinfo_mips *c = &current_cpu_data;
1079 	int tmp;
1080 
1081 	if (config & CONF_SC)
1082 		return 0;
1083 
1084 	begin = (unsigned long) &_stext;
1085 	begin &= ~((4 * 1024 * 1024) - 1);
1086 	end = begin + (4 * 1024 * 1024);
1087 
1088 	/*
1089 	 * This is such a bitch, you'd think they would make it easy to do
1090 	 * this.  Away you daemons of stupidity!
1091 	 */
1092 	local_irq_save(flags);
1093 
1094 	/* Fill each size-multiple cache line with a valid tag. */
1095 	pow2 = (64 * 1024);
1096 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1097 		unsigned long *p = (unsigned long *) addr;
1098 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1099 		pow2 <<= 1;
1100 	}
1101 
1102 	/* Load first line with zero (therefore invalid) tag. */
1103 	write_c0_taglo(0);
1104 	write_c0_taghi(0);
1105 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1106 	cache_op(Index_Store_Tag_I, begin);
1107 	cache_op(Index_Store_Tag_D, begin);
1108 	cache_op(Index_Store_Tag_SD, begin);
1109 
1110 	/* Now search for the wrap around point. */
1111 	pow2 = (128 * 1024);
1112 	tmp = 0;
1113 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1114 		cache_op(Index_Load_Tag_SD, addr);
1115 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1116 		if (!read_c0_taglo())
1117 			break;
1118 		pow2 <<= 1;
1119 	}
1120 	local_irq_restore(flags);
1121 	addr -= begin;
1122 
1123 	scache_size = addr;
1124 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1125 	c->scache.ways = 1;
1126 	c->dcache.waybit = 0;		/* does not matter */
1127 
1128 	return 1;
1129 }
1130 
1131 #if defined(CONFIG_CPU_LOONGSON2)
1132 static void __init loongson2_sc_init(void)
1133 {
1134 	struct cpuinfo_mips *c = &current_cpu_data;
1135 
1136 	scache_size = 512*1024;
1137 	c->scache.linesz = 32;
1138 	c->scache.ways = 4;
1139 	c->scache.waybit = 0;
1140 	c->scache.waysize = scache_size / (c->scache.ways);
1141 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1142 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1143 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1144 
1145 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1146 }
1147 #endif
1148 
1149 extern int r5k_sc_init(void);
1150 extern int rm7k_sc_init(void);
1151 extern int mips_sc_init(void);
1152 
1153 static void __cpuinit setup_scache(void)
1154 {
1155 	struct cpuinfo_mips *c = &current_cpu_data;
1156 	unsigned int config = read_c0_config();
1157 	int sc_present = 0;
1158 
1159 	/*
1160 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1161 	 * processors don't have a S-cache that would be relevant to the
1162 	 * Linux memory management.
1163 	 */
1164 	switch (c->cputype) {
1165 	case CPU_R4000SC:
1166 	case CPU_R4000MC:
1167 	case CPU_R4400SC:
1168 	case CPU_R4400MC:
1169 		sc_present = run_uncached(probe_scache);
1170 		if (sc_present)
1171 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1172 		break;
1173 
1174 	case CPU_R10000:
1175 	case CPU_R12000:
1176 	case CPU_R14000:
1177 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1178 		c->scache.linesz = 64 << ((config >> 13) & 1);
1179 		c->scache.ways = 2;
1180 		c->scache.waybit= 0;
1181 		sc_present = 1;
1182 		break;
1183 
1184 	case CPU_R5000:
1185 	case CPU_NEVADA:
1186 #ifdef CONFIG_R5000_CPU_SCACHE
1187 		r5k_sc_init();
1188 #endif
1189                 return;
1190 
1191 	case CPU_RM7000:
1192 	case CPU_RM9000:
1193 #ifdef CONFIG_RM7000_CPU_SCACHE
1194 		rm7k_sc_init();
1195 #endif
1196 		return;
1197 
1198 #if defined(CONFIG_CPU_LOONGSON2)
1199 	case CPU_LOONGSON2:
1200 		loongson2_sc_init();
1201 		return;
1202 #endif
1203 
1204 	default:
1205 		if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
1206 		    c->isa_level == MIPS_CPU_ISA_M32R2 ||
1207 		    c->isa_level == MIPS_CPU_ISA_M64R1 ||
1208 		    c->isa_level == MIPS_CPU_ISA_M64R2) {
1209 #ifdef CONFIG_MIPS_CPU_SCACHE
1210 			if (mips_sc_init ()) {
1211 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1212 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1213 				       scache_size >> 10,
1214 				       way_string[c->scache.ways], c->scache.linesz);
1215 			}
1216 #else
1217 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1218 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1219 #endif
1220 			return;
1221 		}
1222 		sc_present = 0;
1223 	}
1224 
1225 	if (!sc_present)
1226 		return;
1227 
1228 	/* compute a couple of other cache variables */
1229 	c->scache.waysize = scache_size / c->scache.ways;
1230 
1231 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1232 
1233 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1234 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1235 
1236 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1237 }
1238 
1239 void au1x00_fixup_config_od(void)
1240 {
1241 	/*
1242 	 * c0_config.od (bit 19) was write only (and read as 0)
1243 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1244 	 * transaction overlapping and needs to be set to fix various errata.
1245 	 */
1246 	switch (read_c0_prid()) {
1247 	case 0x00030100: /* Au1000 DA */
1248 	case 0x00030201: /* Au1000 HA */
1249 	case 0x00030202: /* Au1000 HB */
1250 	case 0x01030200: /* Au1500 AB */
1251 	/*
1252 	 * Au1100 errata actually keeps silence about this bit, so we set it
1253 	 * just in case for those revisions that require it to be set according
1254 	 * to the (now gone) cpu table.
1255 	 */
1256 	case 0x02030200: /* Au1100 AB */
1257 	case 0x02030201: /* Au1100 BA */
1258 	case 0x02030202: /* Au1100 BC */
1259 		set_c0_config(1 << 19);
1260 		break;
1261 	}
1262 }
1263 
1264 /* CP0 hazard avoidance. */
1265 #define NXP_BARRIER()							\
1266 	 __asm__ __volatile__(						\
1267 	".set noreorder\n\t"						\
1268 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1269 	".set reorder\n\t")
1270 
1271 static void nxp_pr4450_fixup_config(void)
1272 {
1273 	unsigned long config0;
1274 
1275 	config0 = read_c0_config();
1276 
1277 	/* clear all three cache coherency fields */
1278 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1279 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1280 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1281 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1282 	write_c0_config(config0);
1283 	NXP_BARRIER();
1284 }
1285 
1286 static int __cpuinitdata cca = -1;
1287 
1288 static int __init cca_setup(char *str)
1289 {
1290 	get_option(&str, &cca);
1291 
1292 	return 1;
1293 }
1294 
1295 __setup("cca=", cca_setup);
1296 
1297 static void __cpuinit coherency_setup(void)
1298 {
1299 	if (cca < 0 || cca > 7)
1300 		cca = read_c0_config() & CONF_CM_CMASK;
1301 	_page_cachable_default = cca << _CACHE_SHIFT;
1302 
1303 	pr_debug("Using cache attribute %d\n", cca);
1304 	change_c0_config(CONF_CM_CMASK, cca);
1305 
1306 	/*
1307 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1308 	 * the coherency mode specified by the TLB; 1 means cachable
1309 	 * coherent update on write will be used.  Not all processors have
1310 	 * this bit and; some wire it to zero, others like Toshiba had the
1311 	 * silly idea of putting something else there ...
1312 	 */
1313 	switch (current_cpu_type()) {
1314 	case CPU_R4000PC:
1315 	case CPU_R4000SC:
1316 	case CPU_R4000MC:
1317 	case CPU_R4400PC:
1318 	case CPU_R4400SC:
1319 	case CPU_R4400MC:
1320 		clear_c0_config(CONF_CU);
1321 		break;
1322 	/*
1323 	 * We need to catch the early Alchemy SOCs with
1324 	 * the write-only co_config.od bit and set it back to one on:
1325 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1326 	 */
1327 	case CPU_ALCHEMY:
1328 		au1x00_fixup_config_od();
1329 		break;
1330 
1331 	case PRID_IMP_PR4450:
1332 		nxp_pr4450_fixup_config();
1333 		break;
1334 	}
1335 }
1336 
1337 #if defined(CONFIG_DMA_NONCOHERENT)
1338 
1339 static int __cpuinitdata coherentio;
1340 
1341 static int __init setcoherentio(char *str)
1342 {
1343 	coherentio = 1;
1344 
1345 	return 1;
1346 }
1347 
1348 __setup("coherentio", setcoherentio);
1349 #endif
1350 
1351 void __cpuinit r4k_cache_init(void)
1352 {
1353 	extern void build_clear_page(void);
1354 	extern void build_copy_page(void);
1355 	extern char __weak except_vec2_generic;
1356 	extern char __weak except_vec2_sb1;
1357 	struct cpuinfo_mips *c = &current_cpu_data;
1358 
1359 	switch (c->cputype) {
1360 	case CPU_SB1:
1361 	case CPU_SB1A:
1362 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1363 		break;
1364 
1365 	default:
1366 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1367 		break;
1368 	}
1369 
1370 	probe_pcache();
1371 	setup_scache();
1372 
1373 	r4k_blast_dcache_page_setup();
1374 	r4k_blast_dcache_page_indexed_setup();
1375 	r4k_blast_dcache_setup();
1376 	r4k_blast_icache_page_setup();
1377 	r4k_blast_icache_page_indexed_setup();
1378 	r4k_blast_icache_setup();
1379 	r4k_blast_scache_page_setup();
1380 	r4k_blast_scache_page_indexed_setup();
1381 	r4k_blast_scache_setup();
1382 
1383 	/*
1384 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1385 	 * This code supports virtually indexed processors and will be
1386 	 * unnecessarily inefficient on physically indexed processors.
1387 	 */
1388 	if (c->dcache.linesz)
1389 		shm_align_mask = max_t( unsigned long,
1390 					c->dcache.sets * c->dcache.linesz - 1,
1391 					PAGE_SIZE - 1);
1392 	else
1393 		shm_align_mask = PAGE_SIZE-1;
1394 
1395 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1396 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1397 
1398 	flush_cache_all		= cache_noop;
1399 	__flush_cache_all	= r4k___flush_cache_all;
1400 	flush_cache_mm		= r4k_flush_cache_mm;
1401 	flush_cache_page	= r4k_flush_cache_page;
1402 	flush_cache_range	= r4k_flush_cache_range;
1403 
1404 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1405 	flush_icache_all	= r4k_flush_icache_all;
1406 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1407 	flush_data_cache_page	= r4k_flush_data_cache_page;
1408 	flush_icache_range	= r4k_flush_icache_range;
1409 	local_flush_icache_range	= local_r4k_flush_icache_range;
1410 
1411 #if defined(CONFIG_DMA_NONCOHERENT)
1412 	if (coherentio) {
1413 		_dma_cache_wback_inv	= (void *)cache_noop;
1414 		_dma_cache_wback	= (void *)cache_noop;
1415 		_dma_cache_inv		= (void *)cache_noop;
1416 	} else {
1417 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1418 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1419 		_dma_cache_inv		= r4k_dma_cache_inv;
1420 	}
1421 #endif
1422 
1423 	build_clear_page();
1424 	build_copy_page();
1425 #if !defined(CONFIG_MIPS_CMP)
1426 	local_r4k___flush_cache_all(NULL);
1427 #endif
1428 	coherency_setup();
1429 }
1430