xref: /openbmc/linux/arch/mips/mm/c-r4k.c (revision 8e9356c6)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
7  * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  */
10 #include <linux/hardirq.h>
11 #include <linux/init.h>
12 #include <linux/highmem.h>
13 #include <linux/kernel.h>
14 #include <linux/linkage.h>
15 #include <linux/preempt.h>
16 #include <linux/sched.h>
17 #include <linux/smp.h>
18 #include <linux/mm.h>
19 #include <linux/module.h>
20 #include <linux/bitops.h>
21 
22 #include <asm/bcache.h>
23 #include <asm/bootinfo.h>
24 #include <asm/cache.h>
25 #include <asm/cacheops.h>
26 #include <asm/cpu.h>
27 #include <asm/cpu-features.h>
28 #include <asm/cpu-type.h>
29 #include <asm/io.h>
30 #include <asm/page.h>
31 #include <asm/pgtable.h>
32 #include <asm/r4kcache.h>
33 #include <asm/sections.h>
34 #include <asm/mmu_context.h>
35 #include <asm/war.h>
36 #include <asm/cacheflush.h> /* for run_uncached() */
37 #include <asm/traps.h>
38 #include <asm/dma-coherence.h>
39 
40 /*
41  * Special Variant of smp_call_function for use by cache functions:
42  *
43  *  o No return value
44  *  o collapses to normal function call on UP kernels
45  *  o collapses to normal function call on systems with a single shared
46  *    primary cache.
47  *  o doesn't disable interrupts on the local CPU
48  */
49 static inline void r4k_on_each_cpu(void (*func) (void *info), void *info)
50 {
51 	preempt_disable();
52 
53 #if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
54 	smp_call_function(func, info, 1);
55 #endif
56 	func(info);
57 	preempt_enable();
58 }
59 
60 #if defined(CONFIG_MIPS_CMP)
61 #define cpu_has_safe_index_cacheops 0
62 #else
63 #define cpu_has_safe_index_cacheops 1
64 #endif
65 
66 /*
67  * Must die.
68  */
69 static unsigned long icache_size __read_mostly;
70 static unsigned long dcache_size __read_mostly;
71 static unsigned long scache_size __read_mostly;
72 
73 /*
74  * Dummy cache handling routines for machines without boardcaches
75  */
76 static void cache_noop(void) {}
77 
78 static struct bcache_ops no_sc_ops = {
79 	.bc_enable = (void *)cache_noop,
80 	.bc_disable = (void *)cache_noop,
81 	.bc_wback_inv = (void *)cache_noop,
82 	.bc_inv = (void *)cache_noop
83 };
84 
85 struct bcache_ops *bcops = &no_sc_ops;
86 
87 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
88 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
89 
90 #define R4600_HIT_CACHEOP_WAR_IMPL					\
91 do {									\
92 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
93 		*(volatile unsigned long *)CKSEG1;			\
94 	if (R4600_V1_HIT_CACHEOP_WAR)					\
95 		__asm__ __volatile__("nop;nop;nop;nop");		\
96 } while (0)
97 
98 static void (*r4k_blast_dcache_page)(unsigned long addr);
99 
100 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
101 {
102 	R4600_HIT_CACHEOP_WAR_IMPL;
103 	blast_dcache32_page(addr);
104 }
105 
106 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
107 {
108 	R4600_HIT_CACHEOP_WAR_IMPL;
109 	blast_dcache64_page(addr);
110 }
111 
112 static void r4k_blast_dcache_page_setup(void)
113 {
114 	unsigned long  dc_lsize = cpu_dcache_line_size();
115 
116 	if (dc_lsize == 0)
117 		r4k_blast_dcache_page = (void *)cache_noop;
118 	else if (dc_lsize == 16)
119 		r4k_blast_dcache_page = blast_dcache16_page;
120 	else if (dc_lsize == 32)
121 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
122 	else if (dc_lsize == 64)
123 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
124 }
125 
126 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
127 
128 static void r4k_blast_dcache_page_indexed_setup(void)
129 {
130 	unsigned long dc_lsize = cpu_dcache_line_size();
131 
132 	if (dc_lsize == 0)
133 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
134 	else if (dc_lsize == 16)
135 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
136 	else if (dc_lsize == 32)
137 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
138 	else if (dc_lsize == 64)
139 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
140 }
141 
142 void (* r4k_blast_dcache)(void);
143 EXPORT_SYMBOL(r4k_blast_dcache);
144 
145 static void r4k_blast_dcache_setup(void)
146 {
147 	unsigned long dc_lsize = cpu_dcache_line_size();
148 
149 	if (dc_lsize == 0)
150 		r4k_blast_dcache = (void *)cache_noop;
151 	else if (dc_lsize == 16)
152 		r4k_blast_dcache = blast_dcache16;
153 	else if (dc_lsize == 32)
154 		r4k_blast_dcache = blast_dcache32;
155 	else if (dc_lsize == 64)
156 		r4k_blast_dcache = blast_dcache64;
157 }
158 
159 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
160 #define JUMP_TO_ALIGN(order) \
161 	__asm__ __volatile__( \
162 		"b\t1f\n\t" \
163 		".align\t" #order "\n\t" \
164 		"1:\n\t" \
165 		)
166 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
167 #define CACHE32_UNROLL32_ALIGN2 JUMP_TO_ALIGN(11)
168 
169 static inline void blast_r4600_v1_icache32(void)
170 {
171 	unsigned long flags;
172 
173 	local_irq_save(flags);
174 	blast_icache32();
175 	local_irq_restore(flags);
176 }
177 
178 static inline void tx49_blast_icache32(void)
179 {
180 	unsigned long start = INDEX_BASE;
181 	unsigned long end = start + current_cpu_data.icache.waysize;
182 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
183 	unsigned long ws_end = current_cpu_data.icache.ways <<
184 			       current_cpu_data.icache.waybit;
185 	unsigned long ws, addr;
186 
187 	CACHE32_UNROLL32_ALIGN2;
188 	/* I'm in even chunk.  blast odd chunks */
189 	for (ws = 0; ws < ws_end; ws += ws_inc)
190 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
191 			cache32_unroll32(addr|ws, Index_Invalidate_I);
192 	CACHE32_UNROLL32_ALIGN;
193 	/* I'm in odd chunk.  blast even chunks */
194 	for (ws = 0; ws < ws_end; ws += ws_inc)
195 		for (addr = start; addr < end; addr += 0x400 * 2)
196 			cache32_unroll32(addr|ws, Index_Invalidate_I);
197 }
198 
199 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
200 {
201 	unsigned long flags;
202 
203 	local_irq_save(flags);
204 	blast_icache32_page_indexed(page);
205 	local_irq_restore(flags);
206 }
207 
208 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
209 {
210 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
211 	unsigned long start = INDEX_BASE + (page & indexmask);
212 	unsigned long end = start + PAGE_SIZE;
213 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
214 	unsigned long ws_end = current_cpu_data.icache.ways <<
215 			       current_cpu_data.icache.waybit;
216 	unsigned long ws, addr;
217 
218 	CACHE32_UNROLL32_ALIGN2;
219 	/* I'm in even chunk.  blast odd chunks */
220 	for (ws = 0; ws < ws_end; ws += ws_inc)
221 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
222 			cache32_unroll32(addr|ws, Index_Invalidate_I);
223 	CACHE32_UNROLL32_ALIGN;
224 	/* I'm in odd chunk.  blast even chunks */
225 	for (ws = 0; ws < ws_end; ws += ws_inc)
226 		for (addr = start; addr < end; addr += 0x400 * 2)
227 			cache32_unroll32(addr|ws, Index_Invalidate_I);
228 }
229 
230 static void (* r4k_blast_icache_page)(unsigned long addr);
231 
232 static void r4k_blast_icache_page_setup(void)
233 {
234 	unsigned long ic_lsize = cpu_icache_line_size();
235 
236 	if (ic_lsize == 0)
237 		r4k_blast_icache_page = (void *)cache_noop;
238 	else if (ic_lsize == 16)
239 		r4k_blast_icache_page = blast_icache16_page;
240 	else if (ic_lsize == 32 && current_cpu_type() == CPU_LOONGSON2)
241 		r4k_blast_icache_page = loongson2_blast_icache32_page;
242 	else if (ic_lsize == 32)
243 		r4k_blast_icache_page = blast_icache32_page;
244 	else if (ic_lsize == 64)
245 		r4k_blast_icache_page = blast_icache64_page;
246 }
247 
248 
249 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
250 
251 static void r4k_blast_icache_page_indexed_setup(void)
252 {
253 	unsigned long ic_lsize = cpu_icache_line_size();
254 
255 	if (ic_lsize == 0)
256 		r4k_blast_icache_page_indexed = (void *)cache_noop;
257 	else if (ic_lsize == 16)
258 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
259 	else if (ic_lsize == 32) {
260 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
261 			r4k_blast_icache_page_indexed =
262 				blast_icache32_r4600_v1_page_indexed;
263 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
264 			r4k_blast_icache_page_indexed =
265 				tx49_blast_icache32_page_indexed;
266 		else if (current_cpu_type() == CPU_LOONGSON2)
267 			r4k_blast_icache_page_indexed =
268 				loongson2_blast_icache32_page_indexed;
269 		else
270 			r4k_blast_icache_page_indexed =
271 				blast_icache32_page_indexed;
272 	} else if (ic_lsize == 64)
273 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
274 }
275 
276 void (* r4k_blast_icache)(void);
277 EXPORT_SYMBOL(r4k_blast_icache);
278 
279 static void r4k_blast_icache_setup(void)
280 {
281 	unsigned long ic_lsize = cpu_icache_line_size();
282 
283 	if (ic_lsize == 0)
284 		r4k_blast_icache = (void *)cache_noop;
285 	else if (ic_lsize == 16)
286 		r4k_blast_icache = blast_icache16;
287 	else if (ic_lsize == 32) {
288 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
289 			r4k_blast_icache = blast_r4600_v1_icache32;
290 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
291 			r4k_blast_icache = tx49_blast_icache32;
292 		else if (current_cpu_type() == CPU_LOONGSON2)
293 			r4k_blast_icache = loongson2_blast_icache32;
294 		else
295 			r4k_blast_icache = blast_icache32;
296 	} else if (ic_lsize == 64)
297 		r4k_blast_icache = blast_icache64;
298 }
299 
300 static void (* r4k_blast_scache_page)(unsigned long addr);
301 
302 static void r4k_blast_scache_page_setup(void)
303 {
304 	unsigned long sc_lsize = cpu_scache_line_size();
305 
306 	if (scache_size == 0)
307 		r4k_blast_scache_page = (void *)cache_noop;
308 	else if (sc_lsize == 16)
309 		r4k_blast_scache_page = blast_scache16_page;
310 	else if (sc_lsize == 32)
311 		r4k_blast_scache_page = blast_scache32_page;
312 	else if (sc_lsize == 64)
313 		r4k_blast_scache_page = blast_scache64_page;
314 	else if (sc_lsize == 128)
315 		r4k_blast_scache_page = blast_scache128_page;
316 }
317 
318 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
319 
320 static void r4k_blast_scache_page_indexed_setup(void)
321 {
322 	unsigned long sc_lsize = cpu_scache_line_size();
323 
324 	if (scache_size == 0)
325 		r4k_blast_scache_page_indexed = (void *)cache_noop;
326 	else if (sc_lsize == 16)
327 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
328 	else if (sc_lsize == 32)
329 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
330 	else if (sc_lsize == 64)
331 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
332 	else if (sc_lsize == 128)
333 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
334 }
335 
336 static void (* r4k_blast_scache)(void);
337 
338 static void r4k_blast_scache_setup(void)
339 {
340 	unsigned long sc_lsize = cpu_scache_line_size();
341 
342 	if (scache_size == 0)
343 		r4k_blast_scache = (void *)cache_noop;
344 	else if (sc_lsize == 16)
345 		r4k_blast_scache = blast_scache16;
346 	else if (sc_lsize == 32)
347 		r4k_blast_scache = blast_scache32;
348 	else if (sc_lsize == 64)
349 		r4k_blast_scache = blast_scache64;
350 	else if (sc_lsize == 128)
351 		r4k_blast_scache = blast_scache128;
352 }
353 
354 static inline void local_r4k___flush_cache_all(void * args)
355 {
356 	switch (current_cpu_type()) {
357 	case CPU_LOONGSON2:
358 	case CPU_R4000SC:
359 	case CPU_R4000MC:
360 	case CPU_R4400SC:
361 	case CPU_R4400MC:
362 	case CPU_R10000:
363 	case CPU_R12000:
364 	case CPU_R14000:
365 		/*
366 		 * These caches are inclusive caches, that is, if something
367 		 * is not cached in the S-cache, we know it also won't be
368 		 * in one of the primary caches.
369 		 */
370 		r4k_blast_scache();
371 		break;
372 
373 	default:
374 		r4k_blast_dcache();
375 		r4k_blast_icache();
376 		break;
377 	}
378 }
379 
380 static void r4k___flush_cache_all(void)
381 {
382 	r4k_on_each_cpu(local_r4k___flush_cache_all, NULL);
383 }
384 
385 static inline int has_valid_asid(const struct mm_struct *mm)
386 {
387 #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
388 	int i;
389 
390 	for_each_online_cpu(i)
391 		if (cpu_context(i, mm))
392 			return 1;
393 
394 	return 0;
395 #else
396 	return cpu_context(smp_processor_id(), mm);
397 #endif
398 }
399 
400 static void r4k__flush_cache_vmap(void)
401 {
402 	r4k_blast_dcache();
403 }
404 
405 static void r4k__flush_cache_vunmap(void)
406 {
407 	r4k_blast_dcache();
408 }
409 
410 static inline void local_r4k_flush_cache_range(void * args)
411 {
412 	struct vm_area_struct *vma = args;
413 	int exec = vma->vm_flags & VM_EXEC;
414 
415 	if (!(has_valid_asid(vma->vm_mm)))
416 		return;
417 
418 	r4k_blast_dcache();
419 	if (exec)
420 		r4k_blast_icache();
421 }
422 
423 static void r4k_flush_cache_range(struct vm_area_struct *vma,
424 	unsigned long start, unsigned long end)
425 {
426 	int exec = vma->vm_flags & VM_EXEC;
427 
428 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
429 		r4k_on_each_cpu(local_r4k_flush_cache_range, vma);
430 }
431 
432 static inline void local_r4k_flush_cache_mm(void * args)
433 {
434 	struct mm_struct *mm = args;
435 
436 	if (!has_valid_asid(mm))
437 		return;
438 
439 	/*
440 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
441 	 * only flush the primary caches but R10000 and R12000 behave sane ...
442 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
443 	 * caches, so we can bail out early.
444 	 */
445 	if (current_cpu_type() == CPU_R4000SC ||
446 	    current_cpu_type() == CPU_R4000MC ||
447 	    current_cpu_type() == CPU_R4400SC ||
448 	    current_cpu_type() == CPU_R4400MC) {
449 		r4k_blast_scache();
450 		return;
451 	}
452 
453 	r4k_blast_dcache();
454 }
455 
456 static void r4k_flush_cache_mm(struct mm_struct *mm)
457 {
458 	if (!cpu_has_dc_aliases)
459 		return;
460 
461 	r4k_on_each_cpu(local_r4k_flush_cache_mm, mm);
462 }
463 
464 struct flush_cache_page_args {
465 	struct vm_area_struct *vma;
466 	unsigned long addr;
467 	unsigned long pfn;
468 };
469 
470 static inline void local_r4k_flush_cache_page(void *args)
471 {
472 	struct flush_cache_page_args *fcp_args = args;
473 	struct vm_area_struct *vma = fcp_args->vma;
474 	unsigned long addr = fcp_args->addr;
475 	struct page *page = pfn_to_page(fcp_args->pfn);
476 	int exec = vma->vm_flags & VM_EXEC;
477 	struct mm_struct *mm = vma->vm_mm;
478 	int map_coherent = 0;
479 	pgd_t *pgdp;
480 	pud_t *pudp;
481 	pmd_t *pmdp;
482 	pte_t *ptep;
483 	void *vaddr;
484 
485 	/*
486 	 * If ownes no valid ASID yet, cannot possibly have gotten
487 	 * this page into the cache.
488 	 */
489 	if (!has_valid_asid(mm))
490 		return;
491 
492 	addr &= PAGE_MASK;
493 	pgdp = pgd_offset(mm, addr);
494 	pudp = pud_offset(pgdp, addr);
495 	pmdp = pmd_offset(pudp, addr);
496 	ptep = pte_offset(pmdp, addr);
497 
498 	/*
499 	 * If the page isn't marked valid, the page cannot possibly be
500 	 * in the cache.
501 	 */
502 	if (!(pte_present(*ptep)))
503 		return;
504 
505 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
506 		vaddr = NULL;
507 	else {
508 		/*
509 		 * Use kmap_coherent or kmap_atomic to do flushes for
510 		 * another ASID than the current one.
511 		 */
512 		map_coherent = (cpu_has_dc_aliases &&
513 				page_mapped(page) && !Page_dcache_dirty(page));
514 		if (map_coherent)
515 			vaddr = kmap_coherent(page, addr);
516 		else
517 			vaddr = kmap_atomic(page);
518 		addr = (unsigned long)vaddr;
519 	}
520 
521 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
522 		r4k_blast_dcache_page(addr);
523 		if (exec && !cpu_icache_snoops_remote_store)
524 			r4k_blast_scache_page(addr);
525 	}
526 	if (exec) {
527 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
528 			int cpu = smp_processor_id();
529 
530 			if (cpu_context(cpu, mm) != 0)
531 				drop_mmu_context(mm, cpu);
532 		} else
533 			r4k_blast_icache_page(addr);
534 	}
535 
536 	if (vaddr) {
537 		if (map_coherent)
538 			kunmap_coherent();
539 		else
540 			kunmap_atomic(vaddr);
541 	}
542 }
543 
544 static void r4k_flush_cache_page(struct vm_area_struct *vma,
545 	unsigned long addr, unsigned long pfn)
546 {
547 	struct flush_cache_page_args args;
548 
549 	args.vma = vma;
550 	args.addr = addr;
551 	args.pfn = pfn;
552 
553 	r4k_on_each_cpu(local_r4k_flush_cache_page, &args);
554 }
555 
556 static inline void local_r4k_flush_data_cache_page(void * addr)
557 {
558 	r4k_blast_dcache_page((unsigned long) addr);
559 }
560 
561 static void r4k_flush_data_cache_page(unsigned long addr)
562 {
563 	if (in_atomic())
564 		local_r4k_flush_data_cache_page((void *)addr);
565 	else
566 		r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr);
567 }
568 
569 struct flush_icache_range_args {
570 	unsigned long start;
571 	unsigned long end;
572 };
573 
574 static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
575 {
576 	if (!cpu_has_ic_fills_f_dc) {
577 		if (end - start >= dcache_size) {
578 			r4k_blast_dcache();
579 		} else {
580 			R4600_HIT_CACHEOP_WAR_IMPL;
581 			protected_blast_dcache_range(start, end);
582 		}
583 	}
584 
585 	if (end - start > icache_size)
586 		r4k_blast_icache();
587 	else {
588 		switch (boot_cpu_type()) {
589 		case CPU_LOONGSON2:
590 			protected_loongson2_blast_icache_range(start, end);
591 			break;
592 
593 		default:
594 			protected_blast_icache_range(start, end);
595 			break;
596 		}
597 	}
598 }
599 
600 static inline void local_r4k_flush_icache_range_ipi(void *args)
601 {
602 	struct flush_icache_range_args *fir_args = args;
603 	unsigned long start = fir_args->start;
604 	unsigned long end = fir_args->end;
605 
606 	local_r4k_flush_icache_range(start, end);
607 }
608 
609 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
610 {
611 	struct flush_icache_range_args args;
612 
613 	args.start = start;
614 	args.end = end;
615 
616 	r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args);
617 	instruction_hazard();
618 }
619 
620 #ifdef CONFIG_DMA_NONCOHERENT
621 
622 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
623 {
624 	/* Catch bad driver code */
625 	BUG_ON(size == 0);
626 
627 	preempt_disable();
628 	if (cpu_has_inclusive_pcaches) {
629 		if (size >= scache_size)
630 			r4k_blast_scache();
631 		else
632 			blast_scache_range(addr, addr + size);
633 		preempt_enable();
634 		__sync();
635 		return;
636 	}
637 
638 	/*
639 	 * Either no secondary cache or the available caches don't have the
640 	 * subset property so we have to flush the primary caches
641 	 * explicitly
642 	 */
643 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
644 		r4k_blast_dcache();
645 	} else {
646 		R4600_HIT_CACHEOP_WAR_IMPL;
647 		blast_dcache_range(addr, addr + size);
648 	}
649 	preempt_enable();
650 
651 	bc_wback_inv(addr, size);
652 	__sync();
653 }
654 
655 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
656 {
657 	/* Catch bad driver code */
658 	BUG_ON(size == 0);
659 
660 	preempt_disable();
661 	if (cpu_has_inclusive_pcaches) {
662 		if (size >= scache_size)
663 			r4k_blast_scache();
664 		else {
665 			/*
666 			 * There is no clearly documented alignment requirement
667 			 * for the cache instruction on MIPS processors and
668 			 * some processors, among them the RM5200 and RM7000
669 			 * QED processors will throw an address error for cache
670 			 * hit ops with insufficient alignment.	 Solved by
671 			 * aligning the address to cache line size.
672 			 */
673 			blast_inv_scache_range(addr, addr + size);
674 		}
675 		preempt_enable();
676 		__sync();
677 		return;
678 	}
679 
680 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
681 		r4k_blast_dcache();
682 	} else {
683 		R4600_HIT_CACHEOP_WAR_IMPL;
684 		blast_inv_dcache_range(addr, addr + size);
685 	}
686 	preempt_enable();
687 
688 	bc_inv(addr, size);
689 	__sync();
690 }
691 #endif /* CONFIG_DMA_NONCOHERENT */
692 
693 /*
694  * While we're protected against bad userland addresses we don't care
695  * very much about what happens in that case.  Usually a segmentation
696  * fault will dump the process later on anyway ...
697  */
698 static void local_r4k_flush_cache_sigtramp(void * arg)
699 {
700 	unsigned long ic_lsize = cpu_icache_line_size();
701 	unsigned long dc_lsize = cpu_dcache_line_size();
702 	unsigned long sc_lsize = cpu_scache_line_size();
703 	unsigned long addr = (unsigned long) arg;
704 
705 	R4600_HIT_CACHEOP_WAR_IMPL;
706 	if (dc_lsize)
707 		protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
708 	if (!cpu_icache_snoops_remote_store && scache_size)
709 		protected_writeback_scache_line(addr & ~(sc_lsize - 1));
710 	if (ic_lsize)
711 		protected_flush_icache_line(addr & ~(ic_lsize - 1));
712 	if (MIPS4K_ICACHE_REFILL_WAR) {
713 		__asm__ __volatile__ (
714 			".set push\n\t"
715 			".set noat\n\t"
716 			".set mips3\n\t"
717 #ifdef CONFIG_32BIT
718 			"la	$at,1f\n\t"
719 #endif
720 #ifdef CONFIG_64BIT
721 			"dla	$at,1f\n\t"
722 #endif
723 			"cache	%0,($at)\n\t"
724 			"nop; nop; nop\n"
725 			"1:\n\t"
726 			".set pop"
727 			:
728 			: "i" (Hit_Invalidate_I));
729 	}
730 	if (MIPS_CACHE_SYNC_WAR)
731 		__asm__ __volatile__ ("sync");
732 }
733 
734 static void r4k_flush_cache_sigtramp(unsigned long addr)
735 {
736 	r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr);
737 }
738 
739 static void r4k_flush_icache_all(void)
740 {
741 	if (cpu_has_vtag_icache)
742 		r4k_blast_icache();
743 }
744 
745 struct flush_kernel_vmap_range_args {
746 	unsigned long	vaddr;
747 	int		size;
748 };
749 
750 static inline void local_r4k_flush_kernel_vmap_range(void *args)
751 {
752 	struct flush_kernel_vmap_range_args *vmra = args;
753 	unsigned long vaddr = vmra->vaddr;
754 	int size = vmra->size;
755 
756 	/*
757 	 * Aliases only affect the primary caches so don't bother with
758 	 * S-caches or T-caches.
759 	 */
760 	if (cpu_has_safe_index_cacheops && size >= dcache_size)
761 		r4k_blast_dcache();
762 	else {
763 		R4600_HIT_CACHEOP_WAR_IMPL;
764 		blast_dcache_range(vaddr, vaddr + size);
765 	}
766 }
767 
768 static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
769 {
770 	struct flush_kernel_vmap_range_args args;
771 
772 	args.vaddr = (unsigned long) vaddr;
773 	args.size = size;
774 
775 	r4k_on_each_cpu(local_r4k_flush_kernel_vmap_range, &args);
776 }
777 
778 static inline void rm7k_erratum31(void)
779 {
780 	const unsigned long ic_lsize = 32;
781 	unsigned long addr;
782 
783 	/* RM7000 erratum #31. The icache is screwed at startup. */
784 	write_c0_taglo(0);
785 	write_c0_taghi(0);
786 
787 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
788 		__asm__ __volatile__ (
789 			".set push\n\t"
790 			".set noreorder\n\t"
791 			".set mips3\n\t"
792 			"cache\t%1, 0(%0)\n\t"
793 			"cache\t%1, 0x1000(%0)\n\t"
794 			"cache\t%1, 0x2000(%0)\n\t"
795 			"cache\t%1, 0x3000(%0)\n\t"
796 			"cache\t%2, 0(%0)\n\t"
797 			"cache\t%2, 0x1000(%0)\n\t"
798 			"cache\t%2, 0x2000(%0)\n\t"
799 			"cache\t%2, 0x3000(%0)\n\t"
800 			"cache\t%1, 0(%0)\n\t"
801 			"cache\t%1, 0x1000(%0)\n\t"
802 			"cache\t%1, 0x2000(%0)\n\t"
803 			"cache\t%1, 0x3000(%0)\n\t"
804 			".set pop\n"
805 			:
806 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
807 	}
808 }
809 
810 static inline void alias_74k_erratum(struct cpuinfo_mips *c)
811 {
812 	unsigned int imp = c->processor_id & PRID_IMP_MASK;
813 	unsigned int rev = c->processor_id & PRID_REV_MASK;
814 
815 	/*
816 	 * Early versions of the 74K do not update the cache tags on a
817 	 * vtag miss/ptag hit which can occur in the case of KSEG0/KUSEG
818 	 * aliases. In this case it is better to treat the cache as always
819 	 * having aliases.
820 	 */
821 	switch (imp) {
822 	case PRID_IMP_74K:
823 		if (rev <= PRID_REV_ENCODE_332(2, 4, 0))
824 			c->dcache.flags |= MIPS_CACHE_VTAG;
825 		if (rev == PRID_REV_ENCODE_332(2, 4, 0))
826 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
827 		break;
828 	case PRID_IMP_1074K:
829 		if (rev <= PRID_REV_ENCODE_332(1, 1, 0)) {
830 			c->dcache.flags |= MIPS_CACHE_VTAG;
831 			write_c0_config6(read_c0_config6() | MIPS_CONF6_SYND);
832 		}
833 		break;
834 	default:
835 		BUG();
836 	}
837 }
838 
839 static char *way_string[] = { NULL, "direct mapped", "2-way",
840 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
841 };
842 
843 static void probe_pcache(void)
844 {
845 	struct cpuinfo_mips *c = &current_cpu_data;
846 	unsigned int config = read_c0_config();
847 	unsigned int prid = read_c0_prid();
848 	unsigned long config1;
849 	unsigned int lsize;
850 
851 	switch (current_cpu_type()) {
852 	case CPU_R4600:			/* QED style two way caches? */
853 	case CPU_R4700:
854 	case CPU_R5000:
855 	case CPU_NEVADA:
856 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
857 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
858 		c->icache.ways = 2;
859 		c->icache.waybit = __ffs(icache_size/2);
860 
861 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
862 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
863 		c->dcache.ways = 2;
864 		c->dcache.waybit= __ffs(dcache_size/2);
865 
866 		c->options |= MIPS_CPU_CACHE_CDEX_P;
867 		break;
868 
869 	case CPU_R5432:
870 	case CPU_R5500:
871 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
872 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
873 		c->icache.ways = 2;
874 		c->icache.waybit= 0;
875 
876 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
877 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
878 		c->dcache.ways = 2;
879 		c->dcache.waybit = 0;
880 
881 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
882 		break;
883 
884 	case CPU_TX49XX:
885 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
886 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
887 		c->icache.ways = 4;
888 		c->icache.waybit= 0;
889 
890 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
891 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
892 		c->dcache.ways = 4;
893 		c->dcache.waybit = 0;
894 
895 		c->options |= MIPS_CPU_CACHE_CDEX_P;
896 		c->options |= MIPS_CPU_PREFETCH;
897 		break;
898 
899 	case CPU_R4000PC:
900 	case CPU_R4000SC:
901 	case CPU_R4000MC:
902 	case CPU_R4400PC:
903 	case CPU_R4400SC:
904 	case CPU_R4400MC:
905 	case CPU_R4300:
906 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
907 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
908 		c->icache.ways = 1;
909 		c->icache.waybit = 0;	/* doesn't matter */
910 
911 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
912 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
913 		c->dcache.ways = 1;
914 		c->dcache.waybit = 0;	/* does not matter */
915 
916 		c->options |= MIPS_CPU_CACHE_CDEX_P;
917 		break;
918 
919 	case CPU_R10000:
920 	case CPU_R12000:
921 	case CPU_R14000:
922 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
923 		c->icache.linesz = 64;
924 		c->icache.ways = 2;
925 		c->icache.waybit = 0;
926 
927 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
928 		c->dcache.linesz = 32;
929 		c->dcache.ways = 2;
930 		c->dcache.waybit = 0;
931 
932 		c->options |= MIPS_CPU_PREFETCH;
933 		break;
934 
935 	case CPU_VR4133:
936 		write_c0_config(config & ~VR41_CONF_P4K);
937 	case CPU_VR4131:
938 		/* Workaround for cache instruction bug of VR4131 */
939 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
940 		    c->processor_id == 0x0c82U) {
941 			config |= 0x00400000U;
942 			if (c->processor_id == 0x0c80U)
943 				config |= VR41_CONF_BP;
944 			write_c0_config(config);
945 		} else
946 			c->options |= MIPS_CPU_CACHE_CDEX_P;
947 
948 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
949 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
950 		c->icache.ways = 2;
951 		c->icache.waybit = __ffs(icache_size/2);
952 
953 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
954 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
955 		c->dcache.ways = 2;
956 		c->dcache.waybit = __ffs(dcache_size/2);
957 		break;
958 
959 	case CPU_VR41XX:
960 	case CPU_VR4111:
961 	case CPU_VR4121:
962 	case CPU_VR4122:
963 	case CPU_VR4181:
964 	case CPU_VR4181A:
965 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
966 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
967 		c->icache.ways = 1;
968 		c->icache.waybit = 0;	/* doesn't matter */
969 
970 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
971 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
972 		c->dcache.ways = 1;
973 		c->dcache.waybit = 0;	/* does not matter */
974 
975 		c->options |= MIPS_CPU_CACHE_CDEX_P;
976 		break;
977 
978 	case CPU_RM7000:
979 		rm7k_erratum31();
980 
981 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
982 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
983 		c->icache.ways = 4;
984 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
985 
986 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
987 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
988 		c->dcache.ways = 4;
989 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
990 
991 		c->options |= MIPS_CPU_CACHE_CDEX_P;
992 		c->options |= MIPS_CPU_PREFETCH;
993 		break;
994 
995 	case CPU_LOONGSON2:
996 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
997 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
998 		if (prid & 0x3)
999 			c->icache.ways = 4;
1000 		else
1001 			c->icache.ways = 2;
1002 		c->icache.waybit = 0;
1003 
1004 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
1005 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
1006 		if (prid & 0x3)
1007 			c->dcache.ways = 4;
1008 		else
1009 			c->dcache.ways = 2;
1010 		c->dcache.waybit = 0;
1011 		break;
1012 
1013 	default:
1014 		if (!(config & MIPS_CONF_M))
1015 			panic("Don't know how to probe P-caches on this cpu.");
1016 
1017 		/*
1018 		 * So we seem to be a MIPS32 or MIPS64 CPU
1019 		 * So let's probe the I-cache ...
1020 		 */
1021 		config1 = read_c0_config1();
1022 
1023 		lsize = (config1 >> 19) & 7;
1024 
1025 		/* IL == 7 is reserved */
1026 		if (lsize == 7)
1027 			panic("Invalid icache line size");
1028 
1029 		c->icache.linesz = lsize ? 2 << lsize : 0;
1030 
1031 		c->icache.sets = 32 << (((config1 >> 22) + 1) & 7);
1032 		c->icache.ways = 1 + ((config1 >> 16) & 7);
1033 
1034 		icache_size = c->icache.sets *
1035 			      c->icache.ways *
1036 			      c->icache.linesz;
1037 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
1038 
1039 		if (config & 0x8)		/* VI bit */
1040 			c->icache.flags |= MIPS_CACHE_VTAG;
1041 
1042 		/*
1043 		 * Now probe the MIPS32 / MIPS64 data cache.
1044 		 */
1045 		c->dcache.flags = 0;
1046 
1047 		lsize = (config1 >> 10) & 7;
1048 
1049 		/* DL == 7 is reserved */
1050 		if (lsize == 7)
1051 			panic("Invalid dcache line size");
1052 
1053 		c->dcache.linesz = lsize ? 2 << lsize : 0;
1054 
1055 		c->dcache.sets = 32 << (((config1 >> 13) + 1) & 7);
1056 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1057 
1058 		dcache_size = c->dcache.sets *
1059 			      c->dcache.ways *
1060 			      c->dcache.linesz;
1061 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
1062 
1063 		c->options |= MIPS_CPU_PREFETCH;
1064 		break;
1065 	}
1066 
1067 	/*
1068 	 * Processor configuration sanity check for the R4000SC erratum
1069 	 * #5.	With page sizes larger than 32kB there is no possibility
1070 	 * to get a VCE exception anymore so we don't care about this
1071 	 * misconfiguration.  The case is rather theoretical anyway;
1072 	 * presumably no vendor is shipping his hardware in the "bad"
1073 	 * configuration.
1074 	 */
1075 	if ((prid & PRID_IMP_MASK) == PRID_IMP_R4000 &&
1076 	    (prid & PRID_REV_MASK) < PRID_REV_R4400 &&
1077 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
1078 	    PAGE_SIZE <= 0x8000)
1079 		panic("Improper R4000SC processor configuration detected");
1080 
1081 	/* compute a couple of other cache variables */
1082 	c->icache.waysize = icache_size / c->icache.ways;
1083 	c->dcache.waysize = dcache_size / c->dcache.ways;
1084 
1085 	c->icache.sets = c->icache.linesz ?
1086 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
1087 	c->dcache.sets = c->dcache.linesz ?
1088 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
1089 
1090 	/*
1091 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
1092 	 * 2-way virtually indexed so normally would suffer from aliases.  So
1093 	 * normally they'd suffer from aliases but magic in the hardware deals
1094 	 * with that for us so we don't need to take care ourselves.
1095 	 */
1096 	switch (current_cpu_type()) {
1097 	case CPU_20KC:
1098 	case CPU_25KF:
1099 	case CPU_SB1:
1100 	case CPU_SB1A:
1101 	case CPU_XLR:
1102 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1103 		break;
1104 
1105 	case CPU_R10000:
1106 	case CPU_R12000:
1107 	case CPU_R14000:
1108 		break;
1109 
1110 	case CPU_M14KC:
1111 	case CPU_M14KEC:
1112 	case CPU_24K:
1113 	case CPU_34K:
1114 	case CPU_74K:
1115 	case CPU_1004K:
1116 	case CPU_INTERAPTIV:
1117 	case CPU_PROAPTIV:
1118 		if (current_cpu_type() == CPU_74K)
1119 			alias_74k_erratum(c);
1120 		if ((read_c0_config7() & (1 << 16))) {
1121 			/* effectively physically indexed dcache,
1122 			   thus no virtual aliases. */
1123 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1124 			break;
1125 		}
1126 	default:
1127 		if (c->dcache.waysize > PAGE_SIZE)
1128 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1129 	}
1130 
1131 	switch (current_cpu_type()) {
1132 	case CPU_20KC:
1133 		/*
1134 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1135 		 * the config register.
1136 		 */
1137 		c->icache.flags |= MIPS_CACHE_VTAG;
1138 		break;
1139 
1140 	case CPU_ALCHEMY:
1141 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1142 		break;
1143 
1144 	case CPU_LOONGSON2:
1145 		/*
1146 		 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1147 		 * one op will act on all 4 ways
1148 		 */
1149 		c->icache.ways = 1;
1150 	}
1151 
1152 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1153 	       icache_size >> 10,
1154 	       c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1155 	       way_string[c->icache.ways], c->icache.linesz);
1156 
1157 	printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1158 	       dcache_size >> 10, way_string[c->dcache.ways],
1159 	       (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1160 	       (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1161 			"cache aliases" : "no aliases",
1162 	       c->dcache.linesz);
1163 }
1164 
1165 /*
1166  * If you even _breathe_ on this function, look at the gcc output and make sure
1167  * it does not pop things on and off the stack for the cache sizing loop that
1168  * executes in KSEG1 space or else you will crash and burn badly.  You have
1169  * been warned.
1170  */
1171 static int probe_scache(void)
1172 {
1173 	unsigned long flags, addr, begin, end, pow2;
1174 	unsigned int config = read_c0_config();
1175 	struct cpuinfo_mips *c = &current_cpu_data;
1176 
1177 	if (config & CONF_SC)
1178 		return 0;
1179 
1180 	begin = (unsigned long) &_stext;
1181 	begin &= ~((4 * 1024 * 1024) - 1);
1182 	end = begin + (4 * 1024 * 1024);
1183 
1184 	/*
1185 	 * This is such a bitch, you'd think they would make it easy to do
1186 	 * this.  Away you daemons of stupidity!
1187 	 */
1188 	local_irq_save(flags);
1189 
1190 	/* Fill each size-multiple cache line with a valid tag. */
1191 	pow2 = (64 * 1024);
1192 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1193 		unsigned long *p = (unsigned long *) addr;
1194 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1195 		pow2 <<= 1;
1196 	}
1197 
1198 	/* Load first line with zero (therefore invalid) tag. */
1199 	write_c0_taglo(0);
1200 	write_c0_taghi(0);
1201 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1202 	cache_op(Index_Store_Tag_I, begin);
1203 	cache_op(Index_Store_Tag_D, begin);
1204 	cache_op(Index_Store_Tag_SD, begin);
1205 
1206 	/* Now search for the wrap around point. */
1207 	pow2 = (128 * 1024);
1208 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1209 		cache_op(Index_Load_Tag_SD, addr);
1210 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1211 		if (!read_c0_taglo())
1212 			break;
1213 		pow2 <<= 1;
1214 	}
1215 	local_irq_restore(flags);
1216 	addr -= begin;
1217 
1218 	scache_size = addr;
1219 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1220 	c->scache.ways = 1;
1221 	c->dcache.waybit = 0;		/* does not matter */
1222 
1223 	return 1;
1224 }
1225 
1226 static void __init loongson2_sc_init(void)
1227 {
1228 	struct cpuinfo_mips *c = &current_cpu_data;
1229 
1230 	scache_size = 512*1024;
1231 	c->scache.linesz = 32;
1232 	c->scache.ways = 4;
1233 	c->scache.waybit = 0;
1234 	c->scache.waysize = scache_size / (c->scache.ways);
1235 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1236 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1237 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1238 
1239 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1240 }
1241 
1242 extern int r5k_sc_init(void);
1243 extern int rm7k_sc_init(void);
1244 extern int mips_sc_init(void);
1245 
1246 static void setup_scache(void)
1247 {
1248 	struct cpuinfo_mips *c = &current_cpu_data;
1249 	unsigned int config = read_c0_config();
1250 	int sc_present = 0;
1251 
1252 	/*
1253 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1254 	 * processors don't have a S-cache that would be relevant to the
1255 	 * Linux memory management.
1256 	 */
1257 	switch (current_cpu_type()) {
1258 	case CPU_R4000SC:
1259 	case CPU_R4000MC:
1260 	case CPU_R4400SC:
1261 	case CPU_R4400MC:
1262 		sc_present = run_uncached(probe_scache);
1263 		if (sc_present)
1264 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1265 		break;
1266 
1267 	case CPU_R10000:
1268 	case CPU_R12000:
1269 	case CPU_R14000:
1270 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1271 		c->scache.linesz = 64 << ((config >> 13) & 1);
1272 		c->scache.ways = 2;
1273 		c->scache.waybit= 0;
1274 		sc_present = 1;
1275 		break;
1276 
1277 	case CPU_R5000:
1278 	case CPU_NEVADA:
1279 #ifdef CONFIG_R5000_CPU_SCACHE
1280 		r5k_sc_init();
1281 #endif
1282 		return;
1283 
1284 	case CPU_RM7000:
1285 #ifdef CONFIG_RM7000_CPU_SCACHE
1286 		rm7k_sc_init();
1287 #endif
1288 		return;
1289 
1290 	case CPU_LOONGSON2:
1291 		loongson2_sc_init();
1292 		return;
1293 
1294 	case CPU_XLP:
1295 		/* don't need to worry about L2, fully coherent */
1296 		return;
1297 
1298 	default:
1299 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M32R2 |
1300 				    MIPS_CPU_ISA_M64R1 | MIPS_CPU_ISA_M64R2)) {
1301 #ifdef CONFIG_MIPS_CPU_SCACHE
1302 			if (mips_sc_init ()) {
1303 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1304 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1305 				       scache_size >> 10,
1306 				       way_string[c->scache.ways], c->scache.linesz);
1307 			}
1308 #else
1309 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1310 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1311 #endif
1312 			return;
1313 		}
1314 		sc_present = 0;
1315 	}
1316 
1317 	if (!sc_present)
1318 		return;
1319 
1320 	/* compute a couple of other cache variables */
1321 	c->scache.waysize = scache_size / c->scache.ways;
1322 
1323 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1324 
1325 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1326 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1327 
1328 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1329 }
1330 
1331 void au1x00_fixup_config_od(void)
1332 {
1333 	/*
1334 	 * c0_config.od (bit 19) was write only (and read as 0)
1335 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1336 	 * transaction overlapping and needs to be set to fix various errata.
1337 	 */
1338 	switch (read_c0_prid()) {
1339 	case 0x00030100: /* Au1000 DA */
1340 	case 0x00030201: /* Au1000 HA */
1341 	case 0x00030202: /* Au1000 HB */
1342 	case 0x01030200: /* Au1500 AB */
1343 	/*
1344 	 * Au1100 errata actually keeps silence about this bit, so we set it
1345 	 * just in case for those revisions that require it to be set according
1346 	 * to the (now gone) cpu table.
1347 	 */
1348 	case 0x02030200: /* Au1100 AB */
1349 	case 0x02030201: /* Au1100 BA */
1350 	case 0x02030202: /* Au1100 BC */
1351 		set_c0_config(1 << 19);
1352 		break;
1353 	}
1354 }
1355 
1356 /* CP0 hazard avoidance. */
1357 #define NXP_BARRIER()							\
1358 	 __asm__ __volatile__(						\
1359 	".set noreorder\n\t"						\
1360 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1361 	".set reorder\n\t")
1362 
1363 static void nxp_pr4450_fixup_config(void)
1364 {
1365 	unsigned long config0;
1366 
1367 	config0 = read_c0_config();
1368 
1369 	/* clear all three cache coherency fields */
1370 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1371 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1372 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1373 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1374 	write_c0_config(config0);
1375 	NXP_BARRIER();
1376 }
1377 
1378 static int cca = -1;
1379 
1380 static int __init cca_setup(char *str)
1381 {
1382 	get_option(&str, &cca);
1383 
1384 	return 0;
1385 }
1386 
1387 early_param("cca", cca_setup);
1388 
1389 static void coherency_setup(void)
1390 {
1391 	if (cca < 0 || cca > 7)
1392 		cca = read_c0_config() & CONF_CM_CMASK;
1393 	_page_cachable_default = cca << _CACHE_SHIFT;
1394 
1395 	pr_debug("Using cache attribute %d\n", cca);
1396 	change_c0_config(CONF_CM_CMASK, cca);
1397 
1398 	/*
1399 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1400 	 * the coherency mode specified by the TLB; 1 means cachable
1401 	 * coherent update on write will be used.  Not all processors have
1402 	 * this bit and; some wire it to zero, others like Toshiba had the
1403 	 * silly idea of putting something else there ...
1404 	 */
1405 	switch (current_cpu_type()) {
1406 	case CPU_R4000PC:
1407 	case CPU_R4000SC:
1408 	case CPU_R4000MC:
1409 	case CPU_R4400PC:
1410 	case CPU_R4400SC:
1411 	case CPU_R4400MC:
1412 		clear_c0_config(CONF_CU);
1413 		break;
1414 	/*
1415 	 * We need to catch the early Alchemy SOCs with
1416 	 * the write-only co_config.od bit and set it back to one on:
1417 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1418 	 */
1419 	case CPU_ALCHEMY:
1420 		au1x00_fixup_config_od();
1421 		break;
1422 
1423 	case PRID_IMP_PR4450:
1424 		nxp_pr4450_fixup_config();
1425 		break;
1426 	}
1427 }
1428 
1429 static void r4k_cache_error_setup(void)
1430 {
1431 	extern char __weak except_vec2_generic;
1432 	extern char __weak except_vec2_sb1;
1433 
1434 	switch (current_cpu_type()) {
1435 	case CPU_SB1:
1436 	case CPU_SB1A:
1437 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1438 		break;
1439 
1440 	default:
1441 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1442 		break;
1443 	}
1444 }
1445 
1446 void r4k_cache_init(void)
1447 {
1448 	extern void build_clear_page(void);
1449 	extern void build_copy_page(void);
1450 	struct cpuinfo_mips *c = &current_cpu_data;
1451 
1452 	probe_pcache();
1453 	setup_scache();
1454 
1455 	r4k_blast_dcache_page_setup();
1456 	r4k_blast_dcache_page_indexed_setup();
1457 	r4k_blast_dcache_setup();
1458 	r4k_blast_icache_page_setup();
1459 	r4k_blast_icache_page_indexed_setup();
1460 	r4k_blast_icache_setup();
1461 	r4k_blast_scache_page_setup();
1462 	r4k_blast_scache_page_indexed_setup();
1463 	r4k_blast_scache_setup();
1464 
1465 	/*
1466 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1467 	 * This code supports virtually indexed processors and will be
1468 	 * unnecessarily inefficient on physically indexed processors.
1469 	 */
1470 	if (c->dcache.linesz)
1471 		shm_align_mask = max_t( unsigned long,
1472 					c->dcache.sets * c->dcache.linesz - 1,
1473 					PAGE_SIZE - 1);
1474 	else
1475 		shm_align_mask = PAGE_SIZE-1;
1476 
1477 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1478 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1479 
1480 	flush_cache_all		= cache_noop;
1481 	__flush_cache_all	= r4k___flush_cache_all;
1482 	flush_cache_mm		= r4k_flush_cache_mm;
1483 	flush_cache_page	= r4k_flush_cache_page;
1484 	flush_cache_range	= r4k_flush_cache_range;
1485 
1486 	__flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1487 
1488 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1489 	flush_icache_all	= r4k_flush_icache_all;
1490 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1491 	flush_data_cache_page	= r4k_flush_data_cache_page;
1492 	flush_icache_range	= r4k_flush_icache_range;
1493 	local_flush_icache_range	= local_r4k_flush_icache_range;
1494 
1495 #if defined(CONFIG_DMA_NONCOHERENT)
1496 	if (coherentio) {
1497 		_dma_cache_wback_inv	= (void *)cache_noop;
1498 		_dma_cache_wback	= (void *)cache_noop;
1499 		_dma_cache_inv		= (void *)cache_noop;
1500 	} else {
1501 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1502 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1503 		_dma_cache_inv		= r4k_dma_cache_inv;
1504 	}
1505 #endif
1506 
1507 	build_clear_page();
1508 	build_copy_page();
1509 
1510 	/*
1511 	 * We want to run CMP kernels on core with and without coherent
1512 	 * caches. Therefore, do not use CONFIG_MIPS_CMP to decide whether
1513 	 * or not to flush caches.
1514 	 */
1515 	local_r4k___flush_cache_all(NULL);
1516 
1517 	coherency_setup();
1518 	board_cache_error_setup = r4k_cache_error_setup;
1519 }
1520