xref: /openbmc/linux/arch/mips/mm/c-r4k.c (revision 37185b33)
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/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/mmu_context.h>
33 #include <asm/war.h>
34 #include <asm/cacheflush.h> /* for run_uncached() */
35 #include <asm/traps.h>
36 
37 /*
38  * Special Variant of smp_call_function for use by cache functions:
39  *
40  *  o No return value
41  *  o collapses to normal function call on UP kernels
42  *  o collapses to normal function call on systems with a single shared
43  *    primary cache.
44  *  o doesn't disable interrupts on the local CPU
45  */
46 static inline void r4k_on_each_cpu(void (*func) (void *info), void *info)
47 {
48 	preempt_disable();
49 
50 #if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
51 	smp_call_function(func, info, 1);
52 #endif
53 	func(info);
54 	preempt_enable();
55 }
56 
57 #if defined(CONFIG_MIPS_CMP)
58 #define cpu_has_safe_index_cacheops 0
59 #else
60 #define cpu_has_safe_index_cacheops 1
61 #endif
62 
63 /*
64  * Must die.
65  */
66 static unsigned long icache_size __read_mostly;
67 static unsigned long dcache_size __read_mostly;
68 static unsigned long scache_size __read_mostly;
69 
70 /*
71  * Dummy cache handling routines for machines without boardcaches
72  */
73 static void cache_noop(void) {}
74 
75 static struct bcache_ops no_sc_ops = {
76 	.bc_enable = (void *)cache_noop,
77 	.bc_disable = (void *)cache_noop,
78 	.bc_wback_inv = (void *)cache_noop,
79 	.bc_inv = (void *)cache_noop
80 };
81 
82 struct bcache_ops *bcops = &no_sc_ops;
83 
84 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
85 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)
86 
87 #define R4600_HIT_CACHEOP_WAR_IMPL					\
88 do {									\
89 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
90 		*(volatile unsigned long *)CKSEG1;			\
91 	if (R4600_V1_HIT_CACHEOP_WAR)					\
92 		__asm__ __volatile__("nop;nop;nop;nop");		\
93 } while (0)
94 
95 static void (*r4k_blast_dcache_page)(unsigned long addr);
96 
97 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
98 {
99 	R4600_HIT_CACHEOP_WAR_IMPL;
100 	blast_dcache32_page(addr);
101 }
102 
103 static inline void r4k_blast_dcache_page_dc64(unsigned long addr)
104 {
105 	R4600_HIT_CACHEOP_WAR_IMPL;
106 	blast_dcache64_page(addr);
107 }
108 
109 static void __cpuinit r4k_blast_dcache_page_setup(void)
110 {
111 	unsigned long  dc_lsize = cpu_dcache_line_size();
112 
113 	if (dc_lsize == 0)
114 		r4k_blast_dcache_page = (void *)cache_noop;
115 	else if (dc_lsize == 16)
116 		r4k_blast_dcache_page = blast_dcache16_page;
117 	else if (dc_lsize == 32)
118 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
119 	else if (dc_lsize == 64)
120 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc64;
121 }
122 
123 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
124 
125 static void __cpuinit r4k_blast_dcache_page_indexed_setup(void)
126 {
127 	unsigned long dc_lsize = cpu_dcache_line_size();
128 
129 	if (dc_lsize == 0)
130 		r4k_blast_dcache_page_indexed = (void *)cache_noop;
131 	else if (dc_lsize == 16)
132 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
133 	else if (dc_lsize == 32)
134 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
135 	else if (dc_lsize == 64)
136 		r4k_blast_dcache_page_indexed = blast_dcache64_page_indexed;
137 }
138 
139 static void (* r4k_blast_dcache)(void);
140 
141 static void __cpuinit r4k_blast_dcache_setup(void)
142 {
143 	unsigned long dc_lsize = cpu_dcache_line_size();
144 
145 	if (dc_lsize == 0)
146 		r4k_blast_dcache = (void *)cache_noop;
147 	else if (dc_lsize == 16)
148 		r4k_blast_dcache = blast_dcache16;
149 	else if (dc_lsize == 32)
150 		r4k_blast_dcache = blast_dcache32;
151 	else if (dc_lsize == 64)
152 		r4k_blast_dcache = blast_dcache64;
153 }
154 
155 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
156 #define JUMP_TO_ALIGN(order) \
157 	__asm__ __volatile__( \
158 		"b\t1f\n\t" \
159 		".align\t" #order "\n\t" \
160 		"1:\n\t" \
161 		)
162 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
163 #define CACHE32_UNROLL32_ALIGN2	JUMP_TO_ALIGN(11)
164 
165 static inline void blast_r4600_v1_icache32(void)
166 {
167 	unsigned long flags;
168 
169 	local_irq_save(flags);
170 	blast_icache32();
171 	local_irq_restore(flags);
172 }
173 
174 static inline void tx49_blast_icache32(void)
175 {
176 	unsigned long start = INDEX_BASE;
177 	unsigned long end = start + current_cpu_data.icache.waysize;
178 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
179 	unsigned long ws_end = current_cpu_data.icache.ways <<
180 	                       current_cpu_data.icache.waybit;
181 	unsigned long ws, addr;
182 
183 	CACHE32_UNROLL32_ALIGN2;
184 	/* I'm in even chunk.  blast odd chunks */
185 	for (ws = 0; ws < ws_end; ws += ws_inc)
186 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
187 			cache32_unroll32(addr|ws, Index_Invalidate_I);
188 	CACHE32_UNROLL32_ALIGN;
189 	/* I'm in odd chunk.  blast even chunks */
190 	for (ws = 0; ws < ws_end; ws += ws_inc)
191 		for (addr = start; addr < end; addr += 0x400 * 2)
192 			cache32_unroll32(addr|ws, Index_Invalidate_I);
193 }
194 
195 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
196 {
197 	unsigned long flags;
198 
199 	local_irq_save(flags);
200 	blast_icache32_page_indexed(page);
201 	local_irq_restore(flags);
202 }
203 
204 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
205 {
206 	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
207 	unsigned long start = INDEX_BASE + (page & indexmask);
208 	unsigned long end = start + PAGE_SIZE;
209 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
210 	unsigned long ws_end = current_cpu_data.icache.ways <<
211 	                       current_cpu_data.icache.waybit;
212 	unsigned long ws, addr;
213 
214 	CACHE32_UNROLL32_ALIGN2;
215 	/* I'm in even chunk.  blast odd chunks */
216 	for (ws = 0; ws < ws_end; ws += ws_inc)
217 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
218 			cache32_unroll32(addr|ws, Index_Invalidate_I);
219 	CACHE32_UNROLL32_ALIGN;
220 	/* I'm in odd chunk.  blast even chunks */
221 	for (ws = 0; ws < ws_end; ws += ws_inc)
222 		for (addr = start; addr < end; addr += 0x400 * 2)
223 			cache32_unroll32(addr|ws, Index_Invalidate_I);
224 }
225 
226 static void (* r4k_blast_icache_page)(unsigned long addr);
227 
228 static void __cpuinit r4k_blast_icache_page_setup(void)
229 {
230 	unsigned long ic_lsize = cpu_icache_line_size();
231 
232 	if (ic_lsize == 0)
233 		r4k_blast_icache_page = (void *)cache_noop;
234 	else if (ic_lsize == 16)
235 		r4k_blast_icache_page = blast_icache16_page;
236 	else if (ic_lsize == 32)
237 		r4k_blast_icache_page = blast_icache32_page;
238 	else if (ic_lsize == 64)
239 		r4k_blast_icache_page = blast_icache64_page;
240 }
241 
242 
243 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
244 
245 static void __cpuinit r4k_blast_icache_page_indexed_setup(void)
246 {
247 	unsigned long ic_lsize = cpu_icache_line_size();
248 
249 	if (ic_lsize == 0)
250 		r4k_blast_icache_page_indexed = (void *)cache_noop;
251 	else if (ic_lsize == 16)
252 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
253 	else if (ic_lsize == 32) {
254 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
255 			r4k_blast_icache_page_indexed =
256 				blast_icache32_r4600_v1_page_indexed;
257 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
258 			r4k_blast_icache_page_indexed =
259 				tx49_blast_icache32_page_indexed;
260 		else
261 			r4k_blast_icache_page_indexed =
262 				blast_icache32_page_indexed;
263 	} else if (ic_lsize == 64)
264 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
265 }
266 
267 static void (* r4k_blast_icache)(void);
268 
269 static void __cpuinit r4k_blast_icache_setup(void)
270 {
271 	unsigned long ic_lsize = cpu_icache_line_size();
272 
273 	if (ic_lsize == 0)
274 		r4k_blast_icache = (void *)cache_noop;
275 	else if (ic_lsize == 16)
276 		r4k_blast_icache = blast_icache16;
277 	else if (ic_lsize == 32) {
278 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
279 			r4k_blast_icache = blast_r4600_v1_icache32;
280 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
281 			r4k_blast_icache = tx49_blast_icache32;
282 		else
283 			r4k_blast_icache = blast_icache32;
284 	} else if (ic_lsize == 64)
285 		r4k_blast_icache = blast_icache64;
286 }
287 
288 static void (* r4k_blast_scache_page)(unsigned long addr);
289 
290 static void __cpuinit r4k_blast_scache_page_setup(void)
291 {
292 	unsigned long sc_lsize = cpu_scache_line_size();
293 
294 	if (scache_size == 0)
295 		r4k_blast_scache_page = (void *)cache_noop;
296 	else if (sc_lsize == 16)
297 		r4k_blast_scache_page = blast_scache16_page;
298 	else if (sc_lsize == 32)
299 		r4k_blast_scache_page = blast_scache32_page;
300 	else if (sc_lsize == 64)
301 		r4k_blast_scache_page = blast_scache64_page;
302 	else if (sc_lsize == 128)
303 		r4k_blast_scache_page = blast_scache128_page;
304 }
305 
306 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
307 
308 static void __cpuinit r4k_blast_scache_page_indexed_setup(void)
309 {
310 	unsigned long sc_lsize = cpu_scache_line_size();
311 
312 	if (scache_size == 0)
313 		r4k_blast_scache_page_indexed = (void *)cache_noop;
314 	else if (sc_lsize == 16)
315 		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
316 	else if (sc_lsize == 32)
317 		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
318 	else if (sc_lsize == 64)
319 		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
320 	else if (sc_lsize == 128)
321 		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
322 }
323 
324 static void (* r4k_blast_scache)(void);
325 
326 static void __cpuinit r4k_blast_scache_setup(void)
327 {
328 	unsigned long sc_lsize = cpu_scache_line_size();
329 
330 	if (scache_size == 0)
331 		r4k_blast_scache = (void *)cache_noop;
332 	else if (sc_lsize == 16)
333 		r4k_blast_scache = blast_scache16;
334 	else if (sc_lsize == 32)
335 		r4k_blast_scache = blast_scache32;
336 	else if (sc_lsize == 64)
337 		r4k_blast_scache = blast_scache64;
338 	else if (sc_lsize == 128)
339 		r4k_blast_scache = blast_scache128;
340 }
341 
342 static inline void local_r4k___flush_cache_all(void * args)
343 {
344 #if defined(CONFIG_CPU_LOONGSON2)
345 	r4k_blast_scache();
346 	return;
347 #endif
348 	r4k_blast_dcache();
349 	r4k_blast_icache();
350 
351 	switch (current_cpu_type()) {
352 	case CPU_R4000SC:
353 	case CPU_R4000MC:
354 	case CPU_R4400SC:
355 	case CPU_R4400MC:
356 	case CPU_R10000:
357 	case CPU_R12000:
358 	case CPU_R14000:
359 		r4k_blast_scache();
360 	}
361 }
362 
363 static void r4k___flush_cache_all(void)
364 {
365 	r4k_on_each_cpu(local_r4k___flush_cache_all, NULL);
366 }
367 
368 static inline int has_valid_asid(const struct mm_struct *mm)
369 {
370 #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
371 	int i;
372 
373 	for_each_online_cpu(i)
374 		if (cpu_context(i, mm))
375 			return 1;
376 
377 	return 0;
378 #else
379 	return cpu_context(smp_processor_id(), mm);
380 #endif
381 }
382 
383 static void r4k__flush_cache_vmap(void)
384 {
385 	r4k_blast_dcache();
386 }
387 
388 static void r4k__flush_cache_vunmap(void)
389 {
390 	r4k_blast_dcache();
391 }
392 
393 static inline void local_r4k_flush_cache_range(void * args)
394 {
395 	struct vm_area_struct *vma = args;
396 	int exec = vma->vm_flags & VM_EXEC;
397 
398 	if (!(has_valid_asid(vma->vm_mm)))
399 		return;
400 
401 	r4k_blast_dcache();
402 	if (exec)
403 		r4k_blast_icache();
404 }
405 
406 static void r4k_flush_cache_range(struct vm_area_struct *vma,
407 	unsigned long start, unsigned long end)
408 {
409 	int exec = vma->vm_flags & VM_EXEC;
410 
411 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
412 		r4k_on_each_cpu(local_r4k_flush_cache_range, vma);
413 }
414 
415 static inline void local_r4k_flush_cache_mm(void * args)
416 {
417 	struct mm_struct *mm = args;
418 
419 	if (!has_valid_asid(mm))
420 		return;
421 
422 	/*
423 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
424 	 * only flush the primary caches but R10000 and R12000 behave sane ...
425 	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
426 	 * caches, so we can bail out early.
427 	 */
428 	if (current_cpu_type() == CPU_R4000SC ||
429 	    current_cpu_type() == CPU_R4000MC ||
430 	    current_cpu_type() == CPU_R4400SC ||
431 	    current_cpu_type() == CPU_R4400MC) {
432 		r4k_blast_scache();
433 		return;
434 	}
435 
436 	r4k_blast_dcache();
437 }
438 
439 static void r4k_flush_cache_mm(struct mm_struct *mm)
440 {
441 	if (!cpu_has_dc_aliases)
442 		return;
443 
444 	r4k_on_each_cpu(local_r4k_flush_cache_mm, mm);
445 }
446 
447 struct flush_cache_page_args {
448 	struct vm_area_struct *vma;
449 	unsigned long addr;
450 	unsigned long pfn;
451 };
452 
453 static inline void local_r4k_flush_cache_page(void *args)
454 {
455 	struct flush_cache_page_args *fcp_args = args;
456 	struct vm_area_struct *vma = fcp_args->vma;
457 	unsigned long addr = fcp_args->addr;
458 	struct page *page = pfn_to_page(fcp_args->pfn);
459 	int exec = vma->vm_flags & VM_EXEC;
460 	struct mm_struct *mm = vma->vm_mm;
461 	int map_coherent = 0;
462 	pgd_t *pgdp;
463 	pud_t *pudp;
464 	pmd_t *pmdp;
465 	pte_t *ptep;
466 	void *vaddr;
467 
468 	/*
469 	 * If ownes no valid ASID yet, cannot possibly have gotten
470 	 * this page into the cache.
471 	 */
472 	if (!has_valid_asid(mm))
473 		return;
474 
475 	addr &= PAGE_MASK;
476 	pgdp = pgd_offset(mm, addr);
477 	pudp = pud_offset(pgdp, addr);
478 	pmdp = pmd_offset(pudp, addr);
479 	ptep = pte_offset(pmdp, addr);
480 
481 	/*
482 	 * If the page isn't marked valid, the page cannot possibly be
483 	 * in the cache.
484 	 */
485 	if (!(pte_present(*ptep)))
486 		return;
487 
488 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
489 		vaddr = NULL;
490 	else {
491 		/*
492 		 * Use kmap_coherent or kmap_atomic to do flushes for
493 		 * another ASID than the current one.
494 		 */
495 		map_coherent = (cpu_has_dc_aliases &&
496 				page_mapped(page) && !Page_dcache_dirty(page));
497 		if (map_coherent)
498 			vaddr = kmap_coherent(page, addr);
499 		else
500 			vaddr = kmap_atomic(page);
501 		addr = (unsigned long)vaddr;
502 	}
503 
504 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
505 		r4k_blast_dcache_page(addr);
506 		if (exec && !cpu_icache_snoops_remote_store)
507 			r4k_blast_scache_page(addr);
508 	}
509 	if (exec) {
510 		if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
511 			int cpu = smp_processor_id();
512 
513 			if (cpu_context(cpu, mm) != 0)
514 				drop_mmu_context(mm, cpu);
515 		} else
516 			r4k_blast_icache_page(addr);
517 	}
518 
519 	if (vaddr) {
520 		if (map_coherent)
521 			kunmap_coherent();
522 		else
523 			kunmap_atomic(vaddr);
524 	}
525 }
526 
527 static void r4k_flush_cache_page(struct vm_area_struct *vma,
528 	unsigned long addr, unsigned long pfn)
529 {
530 	struct flush_cache_page_args args;
531 
532 	args.vma = vma;
533 	args.addr = addr;
534 	args.pfn = pfn;
535 
536 	r4k_on_each_cpu(local_r4k_flush_cache_page, &args);
537 }
538 
539 static inline void local_r4k_flush_data_cache_page(void * addr)
540 {
541 	r4k_blast_dcache_page((unsigned long) addr);
542 }
543 
544 static void r4k_flush_data_cache_page(unsigned long addr)
545 {
546 	if (in_atomic())
547 		local_r4k_flush_data_cache_page((void *)addr);
548 	else
549 		r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr);
550 }
551 
552 struct flush_icache_range_args {
553 	unsigned long start;
554 	unsigned long end;
555 };
556 
557 static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
558 {
559 	if (!cpu_has_ic_fills_f_dc) {
560 		if (end - start >= dcache_size) {
561 			r4k_blast_dcache();
562 		} else {
563 			R4600_HIT_CACHEOP_WAR_IMPL;
564 			protected_blast_dcache_range(start, end);
565 		}
566 	}
567 
568 	if (end - start > icache_size)
569 		r4k_blast_icache();
570 	else
571 		protected_blast_icache_range(start, end);
572 }
573 
574 static inline void local_r4k_flush_icache_range_ipi(void *args)
575 {
576 	struct flush_icache_range_args *fir_args = args;
577 	unsigned long start = fir_args->start;
578 	unsigned long end = fir_args->end;
579 
580 	local_r4k_flush_icache_range(start, end);
581 }
582 
583 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
584 {
585 	struct flush_icache_range_args args;
586 
587 	args.start = start;
588 	args.end = end;
589 
590 	r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args);
591 	instruction_hazard();
592 }
593 
594 #ifdef CONFIG_DMA_NONCOHERENT
595 
596 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
597 {
598 	/* Catch bad driver code */
599 	BUG_ON(size == 0);
600 
601 	if (cpu_has_inclusive_pcaches) {
602 		if (size >= scache_size)
603 			r4k_blast_scache();
604 		else
605 			blast_scache_range(addr, addr + size);
606 		__sync();
607 		return;
608 	}
609 
610 	/*
611 	 * Either no secondary cache or the available caches don't have the
612 	 * subset property so we have to flush the primary caches
613 	 * explicitly
614 	 */
615 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
616 		r4k_blast_dcache();
617 	} else {
618 		R4600_HIT_CACHEOP_WAR_IMPL;
619 		blast_dcache_range(addr, addr + size);
620 	}
621 
622 	bc_wback_inv(addr, size);
623 	__sync();
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 		__sync();
652 		return;
653 	}
654 
655 	if (cpu_has_safe_index_cacheops && size >= dcache_size) {
656 		r4k_blast_dcache();
657 	} else {
658 		unsigned long lsize = cpu_dcache_line_size();
659 		unsigned long almask = ~(lsize - 1);
660 
661 		R4600_HIT_CACHEOP_WAR_IMPL;
662 		cache_op(Hit_Writeback_Inv_D, addr & almask);
663 		cache_op(Hit_Writeback_Inv_D, (addr + size - 1)  & almask);
664 		blast_inv_dcache_range(addr, addr + size);
665 	}
666 
667 	bc_inv(addr, size);
668 	__sync();
669 }
670 #endif /* CONFIG_DMA_NONCOHERENT */
671 
672 /*
673  * While we're protected against bad userland addresses we don't care
674  * very much about what happens in that case.  Usually a segmentation
675  * fault will dump the process later on anyway ...
676  */
677 static void local_r4k_flush_cache_sigtramp(void * arg)
678 {
679 	unsigned long ic_lsize = cpu_icache_line_size();
680 	unsigned long dc_lsize = cpu_dcache_line_size();
681 	unsigned long sc_lsize = cpu_scache_line_size();
682 	unsigned long addr = (unsigned long) arg;
683 
684 	R4600_HIT_CACHEOP_WAR_IMPL;
685 	if (dc_lsize)
686 		protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
687 	if (!cpu_icache_snoops_remote_store && scache_size)
688 		protected_writeback_scache_line(addr & ~(sc_lsize - 1));
689 	if (ic_lsize)
690 		protected_flush_icache_line(addr & ~(ic_lsize - 1));
691 	if (MIPS4K_ICACHE_REFILL_WAR) {
692 		__asm__ __volatile__ (
693 			".set push\n\t"
694 			".set noat\n\t"
695 			".set mips3\n\t"
696 #ifdef CONFIG_32BIT
697 			"la	$at,1f\n\t"
698 #endif
699 #ifdef CONFIG_64BIT
700 			"dla	$at,1f\n\t"
701 #endif
702 			"cache	%0,($at)\n\t"
703 			"nop; nop; nop\n"
704 			"1:\n\t"
705 			".set pop"
706 			:
707 			: "i" (Hit_Invalidate_I));
708 	}
709 	if (MIPS_CACHE_SYNC_WAR)
710 		__asm__ __volatile__ ("sync");
711 }
712 
713 static void r4k_flush_cache_sigtramp(unsigned long addr)
714 {
715 	r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr);
716 }
717 
718 static void r4k_flush_icache_all(void)
719 {
720 	if (cpu_has_vtag_icache)
721 		r4k_blast_icache();
722 }
723 
724 struct flush_kernel_vmap_range_args {
725 	unsigned long	vaddr;
726 	int		size;
727 };
728 
729 static inline void local_r4k_flush_kernel_vmap_range(void *args)
730 {
731 	struct flush_kernel_vmap_range_args *vmra = args;
732 	unsigned long vaddr = vmra->vaddr;
733 	int size = vmra->size;
734 
735 	/*
736 	 * Aliases only affect the primary caches so don't bother with
737 	 * S-caches or T-caches.
738 	 */
739 	if (cpu_has_safe_index_cacheops && size >= dcache_size)
740 		r4k_blast_dcache();
741 	else {
742 		R4600_HIT_CACHEOP_WAR_IMPL;
743 		blast_dcache_range(vaddr, vaddr + size);
744 	}
745 }
746 
747 static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
748 {
749 	struct flush_kernel_vmap_range_args args;
750 
751 	args.vaddr = (unsigned long) vaddr;
752 	args.size = size;
753 
754 	r4k_on_each_cpu(local_r4k_flush_kernel_vmap_range, &args);
755 }
756 
757 static inline void rm7k_erratum31(void)
758 {
759 	const unsigned long ic_lsize = 32;
760 	unsigned long addr;
761 
762 	/* RM7000 erratum #31. The icache is screwed at startup. */
763 	write_c0_taglo(0);
764 	write_c0_taghi(0);
765 
766 	for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
767 		__asm__ __volatile__ (
768 			".set push\n\t"
769 			".set noreorder\n\t"
770 			".set mips3\n\t"
771 			"cache\t%1, 0(%0)\n\t"
772 			"cache\t%1, 0x1000(%0)\n\t"
773 			"cache\t%1, 0x2000(%0)\n\t"
774 			"cache\t%1, 0x3000(%0)\n\t"
775 			"cache\t%2, 0(%0)\n\t"
776 			"cache\t%2, 0x1000(%0)\n\t"
777 			"cache\t%2, 0x2000(%0)\n\t"
778 			"cache\t%2, 0x3000(%0)\n\t"
779 			"cache\t%1, 0(%0)\n\t"
780 			"cache\t%1, 0x1000(%0)\n\t"
781 			"cache\t%1, 0x2000(%0)\n\t"
782 			"cache\t%1, 0x3000(%0)\n\t"
783 			".set pop\n"
784 			:
785 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
786 	}
787 }
788 
789 static char *way_string[] __cpuinitdata = { NULL, "direct mapped", "2-way",
790 	"3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
791 };
792 
793 static void __cpuinit probe_pcache(void)
794 {
795 	struct cpuinfo_mips *c = &current_cpu_data;
796 	unsigned int config = read_c0_config();
797 	unsigned int prid = read_c0_prid();
798 	unsigned long config1;
799 	unsigned int lsize;
800 
801 	switch (c->cputype) {
802 	case CPU_R4600:			/* QED style two way caches? */
803 	case CPU_R4700:
804 	case CPU_R5000:
805 	case CPU_NEVADA:
806 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
807 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
808 		c->icache.ways = 2;
809 		c->icache.waybit = __ffs(icache_size/2);
810 
811 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
812 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
813 		c->dcache.ways = 2;
814 		c->dcache.waybit= __ffs(dcache_size/2);
815 
816 		c->options |= MIPS_CPU_CACHE_CDEX_P;
817 		break;
818 
819 	case CPU_R5432:
820 	case CPU_R5500:
821 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
822 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
823 		c->icache.ways = 2;
824 		c->icache.waybit= 0;
825 
826 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
827 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
828 		c->dcache.ways = 2;
829 		c->dcache.waybit = 0;
830 
831 		c->options |= MIPS_CPU_CACHE_CDEX_P | MIPS_CPU_PREFETCH;
832 		break;
833 
834 	case CPU_TX49XX:
835 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
836 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
837 		c->icache.ways = 4;
838 		c->icache.waybit= 0;
839 
840 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
841 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
842 		c->dcache.ways = 4;
843 		c->dcache.waybit = 0;
844 
845 		c->options |= MIPS_CPU_CACHE_CDEX_P;
846 		c->options |= MIPS_CPU_PREFETCH;
847 		break;
848 
849 	case CPU_R4000PC:
850 	case CPU_R4000SC:
851 	case CPU_R4000MC:
852 	case CPU_R4400PC:
853 	case CPU_R4400SC:
854 	case CPU_R4400MC:
855 	case CPU_R4300:
856 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
857 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
858 		c->icache.ways = 1;
859 		c->icache.waybit = 0; 	/* doesn't matter */
860 
861 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
862 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
863 		c->dcache.ways = 1;
864 		c->dcache.waybit = 0;	/* does not matter */
865 
866 		c->options |= MIPS_CPU_CACHE_CDEX_P;
867 		break;
868 
869 	case CPU_R10000:
870 	case CPU_R12000:
871 	case CPU_R14000:
872 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
873 		c->icache.linesz = 64;
874 		c->icache.ways = 2;
875 		c->icache.waybit = 0;
876 
877 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
878 		c->dcache.linesz = 32;
879 		c->dcache.ways = 2;
880 		c->dcache.waybit = 0;
881 
882 		c->options |= MIPS_CPU_PREFETCH;
883 		break;
884 
885 	case CPU_VR4133:
886 		write_c0_config(config & ~VR41_CONF_P4K);
887 	case CPU_VR4131:
888 		/* Workaround for cache instruction bug of VR4131 */
889 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
890 		    c->processor_id == 0x0c82U) {
891 			config |= 0x00400000U;
892 			if (c->processor_id == 0x0c80U)
893 				config |= VR41_CONF_BP;
894 			write_c0_config(config);
895 		} else
896 			c->options |= MIPS_CPU_CACHE_CDEX_P;
897 
898 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
899 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
900 		c->icache.ways = 2;
901 		c->icache.waybit = __ffs(icache_size/2);
902 
903 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
904 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
905 		c->dcache.ways = 2;
906 		c->dcache.waybit = __ffs(dcache_size/2);
907 		break;
908 
909 	case CPU_VR41XX:
910 	case CPU_VR4111:
911 	case CPU_VR4121:
912 	case CPU_VR4122:
913 	case CPU_VR4181:
914 	case CPU_VR4181A:
915 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
916 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
917 		c->icache.ways = 1;
918 		c->icache.waybit = 0; 	/* doesn't matter */
919 
920 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
921 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
922 		c->dcache.ways = 1;
923 		c->dcache.waybit = 0;	/* does not matter */
924 
925 		c->options |= MIPS_CPU_CACHE_CDEX_P;
926 		break;
927 
928 	case CPU_RM7000:
929 		rm7k_erratum31();
930 
931 	case CPU_RM9000:
932 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
933 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
934 		c->icache.ways = 4;
935 		c->icache.waybit = __ffs(icache_size / c->icache.ways);
936 
937 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
938 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
939 		c->dcache.ways = 4;
940 		c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
941 
942 #if !defined(CONFIG_SMP) || !defined(RM9000_CDEX_SMP_WAR)
943 		c->options |= MIPS_CPU_CACHE_CDEX_P;
944 #endif
945 		c->options |= MIPS_CPU_PREFETCH;
946 		break;
947 
948 	case CPU_LOONGSON2:
949 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
950 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
951 		if (prid & 0x3)
952 			c->icache.ways = 4;
953 		else
954 			c->icache.ways = 2;
955 		c->icache.waybit = 0;
956 
957 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
958 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
959 		if (prid & 0x3)
960 			c->dcache.ways = 4;
961 		else
962 			c->dcache.ways = 2;
963 		c->dcache.waybit = 0;
964 		break;
965 
966 	default:
967 		if (!(config & MIPS_CONF_M))
968 			panic("Don't know how to probe P-caches on this cpu.");
969 
970 		/*
971 		 * So we seem to be a MIPS32 or MIPS64 CPU
972 		 * So let's probe the I-cache ...
973 		 */
974 		config1 = read_c0_config1();
975 
976 		if ((lsize = ((config1 >> 19) & 7)))
977 			c->icache.linesz = 2 << lsize;
978 		else
979 			c->icache.linesz = lsize;
980 		c->icache.sets = 32 << (((config1 >> 22) + 1) & 7);
981 		c->icache.ways = 1 + ((config1 >> 16) & 7);
982 
983 		icache_size = c->icache.sets *
984 		              c->icache.ways *
985 		              c->icache.linesz;
986 		c->icache.waybit = __ffs(icache_size/c->icache.ways);
987 
988 		if (config & 0x8)		/* VI bit */
989 			c->icache.flags |= MIPS_CACHE_VTAG;
990 
991 		/*
992 		 * Now probe the MIPS32 / MIPS64 data cache.
993 		 */
994 		c->dcache.flags = 0;
995 
996 		if ((lsize = ((config1 >> 10) & 7)))
997 			c->dcache.linesz = 2 << lsize;
998 		else
999 			c->dcache.linesz= lsize;
1000 		c->dcache.sets = 32 << (((config1 >> 13) + 1) & 7);
1001 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
1002 
1003 		dcache_size = c->dcache.sets *
1004 		              c->dcache.ways *
1005 		              c->dcache.linesz;
1006 		c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
1007 
1008 		c->options |= MIPS_CPU_PREFETCH;
1009 		break;
1010 	}
1011 
1012 	/*
1013 	 * Processor configuration sanity check for the R4000SC erratum
1014 	 * #5.  With page sizes larger than 32kB there is no possibility
1015 	 * to get a VCE exception anymore so we don't care about this
1016 	 * misconfiguration.  The case is rather theoretical anyway;
1017 	 * presumably no vendor is shipping his hardware in the "bad"
1018 	 * configuration.
1019 	 */
1020 	if ((prid & 0xff00) == PRID_IMP_R4000 && (prid & 0xff) < 0x40 &&
1021 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
1022 	    PAGE_SIZE <= 0x8000)
1023 		panic("Improper R4000SC processor configuration detected");
1024 
1025 	/* compute a couple of other cache variables */
1026 	c->icache.waysize = icache_size / c->icache.ways;
1027 	c->dcache.waysize = dcache_size / c->dcache.ways;
1028 
1029 	c->icache.sets = c->icache.linesz ?
1030 		icache_size / (c->icache.linesz * c->icache.ways) : 0;
1031 	c->dcache.sets = c->dcache.linesz ?
1032 		dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
1033 
1034 	/*
1035 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
1036 	 * 2-way virtually indexed so normally would suffer from aliases.  So
1037 	 * normally they'd suffer from aliases but magic in the hardware deals
1038 	 * with that for us so we don't need to take care ourselves.
1039 	 */
1040 	switch (c->cputype) {
1041 	case CPU_20KC:
1042 	case CPU_25KF:
1043 	case CPU_SB1:
1044 	case CPU_SB1A:
1045 	case CPU_XLR:
1046 		c->dcache.flags |= MIPS_CACHE_PINDEX;
1047 		break;
1048 
1049 	case CPU_R10000:
1050 	case CPU_R12000:
1051 	case CPU_R14000:
1052 		break;
1053 
1054 	case CPU_M14KC:
1055 	case CPU_24K:
1056 	case CPU_34K:
1057 	case CPU_74K:
1058 	case CPU_1004K:
1059 		if ((read_c0_config7() & (1 << 16))) {
1060 			/* effectively physically indexed dcache,
1061 			   thus no virtual aliases. */
1062 			c->dcache.flags |= MIPS_CACHE_PINDEX;
1063 			break;
1064 		}
1065 	default:
1066 		if (c->dcache.waysize > PAGE_SIZE)
1067 			c->dcache.flags |= MIPS_CACHE_ALIASES;
1068 	}
1069 
1070 	switch (c->cputype) {
1071 	case CPU_20KC:
1072 		/*
1073 		 * Some older 20Kc chips doesn't have the 'VI' bit in
1074 		 * the config register.
1075 		 */
1076 		c->icache.flags |= MIPS_CACHE_VTAG;
1077 		break;
1078 
1079 	case CPU_ALCHEMY:
1080 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
1081 		break;
1082 	}
1083 
1084 #ifdef  CONFIG_CPU_LOONGSON2
1085 	/*
1086 	 * LOONGSON2 has 4 way icache, but when using indexed cache op,
1087 	 * one op will act on all 4 ways
1088 	 */
1089 	c->icache.ways = 1;
1090 #endif
1091 
1092 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1093 	       icache_size >> 10,
1094 	       c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1095 	       way_string[c->icache.ways], c->icache.linesz);
1096 
1097 	printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1098 	       dcache_size >> 10, way_string[c->dcache.ways],
1099 	       (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1100 	       (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1101 			"cache aliases" : "no aliases",
1102 	       c->dcache.linesz);
1103 }
1104 
1105 /*
1106  * If you even _breathe_ on this function, look at the gcc output and make sure
1107  * it does not pop things on and off the stack for the cache sizing loop that
1108  * executes in KSEG1 space or else you will crash and burn badly.  You have
1109  * been warned.
1110  */
1111 static int __cpuinit probe_scache(void)
1112 {
1113 	unsigned long flags, addr, begin, end, pow2;
1114 	unsigned int config = read_c0_config();
1115 	struct cpuinfo_mips *c = &current_cpu_data;
1116 
1117 	if (config & CONF_SC)
1118 		return 0;
1119 
1120 	begin = (unsigned long) &_stext;
1121 	begin &= ~((4 * 1024 * 1024) - 1);
1122 	end = begin + (4 * 1024 * 1024);
1123 
1124 	/*
1125 	 * This is such a bitch, you'd think they would make it easy to do
1126 	 * this.  Away you daemons of stupidity!
1127 	 */
1128 	local_irq_save(flags);
1129 
1130 	/* Fill each size-multiple cache line with a valid tag. */
1131 	pow2 = (64 * 1024);
1132 	for (addr = begin; addr < end; addr = (begin + pow2)) {
1133 		unsigned long *p = (unsigned long *) addr;
1134 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1135 		pow2 <<= 1;
1136 	}
1137 
1138 	/* Load first line with zero (therefore invalid) tag. */
1139 	write_c0_taglo(0);
1140 	write_c0_taghi(0);
1141 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1142 	cache_op(Index_Store_Tag_I, begin);
1143 	cache_op(Index_Store_Tag_D, begin);
1144 	cache_op(Index_Store_Tag_SD, begin);
1145 
1146 	/* Now search for the wrap around point. */
1147 	pow2 = (128 * 1024);
1148 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1149 		cache_op(Index_Load_Tag_SD, addr);
1150 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1151 		if (!read_c0_taglo())
1152 			break;
1153 		pow2 <<= 1;
1154 	}
1155 	local_irq_restore(flags);
1156 	addr -= begin;
1157 
1158 	scache_size = addr;
1159 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1160 	c->scache.ways = 1;
1161 	c->dcache.waybit = 0;		/* does not matter */
1162 
1163 	return 1;
1164 }
1165 
1166 #if defined(CONFIG_CPU_LOONGSON2)
1167 static void __init loongson2_sc_init(void)
1168 {
1169 	struct cpuinfo_mips *c = &current_cpu_data;
1170 
1171 	scache_size = 512*1024;
1172 	c->scache.linesz = 32;
1173 	c->scache.ways = 4;
1174 	c->scache.waybit = 0;
1175 	c->scache.waysize = scache_size / (c->scache.ways);
1176 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1177 	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1178 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1179 
1180 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1181 }
1182 #endif
1183 
1184 extern int r5k_sc_init(void);
1185 extern int rm7k_sc_init(void);
1186 extern int mips_sc_init(void);
1187 
1188 static void __cpuinit setup_scache(void)
1189 {
1190 	struct cpuinfo_mips *c = &current_cpu_data;
1191 	unsigned int config = read_c0_config();
1192 	int sc_present = 0;
1193 
1194 	/*
1195 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
1196 	 * processors don't have a S-cache that would be relevant to the
1197 	 * Linux memory management.
1198 	 */
1199 	switch (c->cputype) {
1200 	case CPU_R4000SC:
1201 	case CPU_R4000MC:
1202 	case CPU_R4400SC:
1203 	case CPU_R4400MC:
1204 		sc_present = run_uncached(probe_scache);
1205 		if (sc_present)
1206 			c->options |= MIPS_CPU_CACHE_CDEX_S;
1207 		break;
1208 
1209 	case CPU_R10000:
1210 	case CPU_R12000:
1211 	case CPU_R14000:
1212 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1213 		c->scache.linesz = 64 << ((config >> 13) & 1);
1214 		c->scache.ways = 2;
1215 		c->scache.waybit= 0;
1216 		sc_present = 1;
1217 		break;
1218 
1219 	case CPU_R5000:
1220 	case CPU_NEVADA:
1221 #ifdef CONFIG_R5000_CPU_SCACHE
1222 		r5k_sc_init();
1223 #endif
1224                 return;
1225 
1226 	case CPU_RM7000:
1227 	case CPU_RM9000:
1228 #ifdef CONFIG_RM7000_CPU_SCACHE
1229 		rm7k_sc_init();
1230 #endif
1231 		return;
1232 
1233 #if defined(CONFIG_CPU_LOONGSON2)
1234 	case CPU_LOONGSON2:
1235 		loongson2_sc_init();
1236 		return;
1237 #endif
1238 	case CPU_XLP:
1239 		/* don't need to worry about L2, fully coherent */
1240 		return;
1241 
1242 	default:
1243 		if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
1244 		    c->isa_level == MIPS_CPU_ISA_M32R2 ||
1245 		    c->isa_level == MIPS_CPU_ISA_M64R1 ||
1246 		    c->isa_level == MIPS_CPU_ISA_M64R2) {
1247 #ifdef CONFIG_MIPS_CPU_SCACHE
1248 			if (mips_sc_init ()) {
1249 				scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1250 				printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1251 				       scache_size >> 10,
1252 				       way_string[c->scache.ways], c->scache.linesz);
1253 			}
1254 #else
1255 			if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1256 				panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1257 #endif
1258 			return;
1259 		}
1260 		sc_present = 0;
1261 	}
1262 
1263 	if (!sc_present)
1264 		return;
1265 
1266 	/* compute a couple of other cache variables */
1267 	c->scache.waysize = scache_size / c->scache.ways;
1268 
1269 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1270 
1271 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1272 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1273 
1274 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1275 }
1276 
1277 void au1x00_fixup_config_od(void)
1278 {
1279 	/*
1280 	 * c0_config.od (bit 19) was write only (and read as 0)
1281 	 * on the early revisions of Alchemy SOCs.  It disables the bus
1282 	 * transaction overlapping and needs to be set to fix various errata.
1283 	 */
1284 	switch (read_c0_prid()) {
1285 	case 0x00030100: /* Au1000 DA */
1286 	case 0x00030201: /* Au1000 HA */
1287 	case 0x00030202: /* Au1000 HB */
1288 	case 0x01030200: /* Au1500 AB */
1289 	/*
1290 	 * Au1100 errata actually keeps silence about this bit, so we set it
1291 	 * just in case for those revisions that require it to be set according
1292 	 * to the (now gone) cpu table.
1293 	 */
1294 	case 0x02030200: /* Au1100 AB */
1295 	case 0x02030201: /* Au1100 BA */
1296 	case 0x02030202: /* Au1100 BC */
1297 		set_c0_config(1 << 19);
1298 		break;
1299 	}
1300 }
1301 
1302 /* CP0 hazard avoidance. */
1303 #define NXP_BARRIER()							\
1304 	 __asm__ __volatile__(						\
1305 	".set noreorder\n\t"						\
1306 	"nop; nop; nop; nop; nop; nop;\n\t"				\
1307 	".set reorder\n\t")
1308 
1309 static void nxp_pr4450_fixup_config(void)
1310 {
1311 	unsigned long config0;
1312 
1313 	config0 = read_c0_config();
1314 
1315 	/* clear all three cache coherency fields */
1316 	config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1317 	config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1318 		    ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1319 		    ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1320 	write_c0_config(config0);
1321 	NXP_BARRIER();
1322 }
1323 
1324 static int __cpuinitdata cca = -1;
1325 
1326 static int __init cca_setup(char *str)
1327 {
1328 	get_option(&str, &cca);
1329 
1330 	return 1;
1331 }
1332 
1333 __setup("cca=", cca_setup);
1334 
1335 static void __cpuinit coherency_setup(void)
1336 {
1337 	if (cca < 0 || cca > 7)
1338 		cca = read_c0_config() & CONF_CM_CMASK;
1339 	_page_cachable_default = cca << _CACHE_SHIFT;
1340 
1341 	pr_debug("Using cache attribute %d\n", cca);
1342 	change_c0_config(CONF_CM_CMASK, cca);
1343 
1344 	/*
1345 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1346 	 * the coherency mode specified by the TLB; 1 means cachable
1347 	 * coherent update on write will be used.  Not all processors have
1348 	 * this bit and; some wire it to zero, others like Toshiba had the
1349 	 * silly idea of putting something else there ...
1350 	 */
1351 	switch (current_cpu_type()) {
1352 	case CPU_R4000PC:
1353 	case CPU_R4000SC:
1354 	case CPU_R4000MC:
1355 	case CPU_R4400PC:
1356 	case CPU_R4400SC:
1357 	case CPU_R4400MC:
1358 		clear_c0_config(CONF_CU);
1359 		break;
1360 	/*
1361 	 * We need to catch the early Alchemy SOCs with
1362 	 * the write-only co_config.od bit and set it back to one on:
1363 	 * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1364 	 */
1365 	case CPU_ALCHEMY:
1366 		au1x00_fixup_config_od();
1367 		break;
1368 
1369 	case PRID_IMP_PR4450:
1370 		nxp_pr4450_fixup_config();
1371 		break;
1372 	}
1373 }
1374 
1375 #if defined(CONFIG_DMA_NONCOHERENT)
1376 
1377 static int __cpuinitdata coherentio;
1378 
1379 static int __init setcoherentio(char *str)
1380 {
1381 	coherentio = 1;
1382 
1383 	return 1;
1384 }
1385 
1386 __setup("coherentio", setcoherentio);
1387 #endif
1388 
1389 static void __cpuinit r4k_cache_error_setup(void)
1390 {
1391 	extern char __weak except_vec2_generic;
1392 	extern char __weak except_vec2_sb1;
1393 	struct cpuinfo_mips *c = &current_cpu_data;
1394 
1395 	switch (c->cputype) {
1396 	case CPU_SB1:
1397 	case CPU_SB1A:
1398 		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1399 		break;
1400 
1401 	default:
1402 		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1403 		break;
1404 	}
1405 }
1406 
1407 void __cpuinit r4k_cache_init(void)
1408 {
1409 	extern void build_clear_page(void);
1410 	extern void build_copy_page(void);
1411 	struct cpuinfo_mips *c = &current_cpu_data;
1412 
1413 	probe_pcache();
1414 	setup_scache();
1415 
1416 	r4k_blast_dcache_page_setup();
1417 	r4k_blast_dcache_page_indexed_setup();
1418 	r4k_blast_dcache_setup();
1419 	r4k_blast_icache_page_setup();
1420 	r4k_blast_icache_page_indexed_setup();
1421 	r4k_blast_icache_setup();
1422 	r4k_blast_scache_page_setup();
1423 	r4k_blast_scache_page_indexed_setup();
1424 	r4k_blast_scache_setup();
1425 
1426 	/*
1427 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1428 	 * This code supports virtually indexed processors and will be
1429 	 * unnecessarily inefficient on physically indexed processors.
1430 	 */
1431 	if (c->dcache.linesz)
1432 		shm_align_mask = max_t( unsigned long,
1433 					c->dcache.sets * c->dcache.linesz - 1,
1434 					PAGE_SIZE - 1);
1435 	else
1436 		shm_align_mask = PAGE_SIZE-1;
1437 
1438 	__flush_cache_vmap	= r4k__flush_cache_vmap;
1439 	__flush_cache_vunmap	= r4k__flush_cache_vunmap;
1440 
1441 	flush_cache_all		= cache_noop;
1442 	__flush_cache_all	= r4k___flush_cache_all;
1443 	flush_cache_mm		= r4k_flush_cache_mm;
1444 	flush_cache_page	= r4k_flush_cache_page;
1445 	flush_cache_range	= r4k_flush_cache_range;
1446 
1447 	__flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1448 
1449 	flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1450 	flush_icache_all	= r4k_flush_icache_all;
1451 	local_flush_data_cache_page	= local_r4k_flush_data_cache_page;
1452 	flush_data_cache_page	= r4k_flush_data_cache_page;
1453 	flush_icache_range	= r4k_flush_icache_range;
1454 	local_flush_icache_range	= local_r4k_flush_icache_range;
1455 
1456 #if defined(CONFIG_DMA_NONCOHERENT)
1457 	if (coherentio) {
1458 		_dma_cache_wback_inv	= (void *)cache_noop;
1459 		_dma_cache_wback	= (void *)cache_noop;
1460 		_dma_cache_inv		= (void *)cache_noop;
1461 	} else {
1462 		_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1463 		_dma_cache_wback	= r4k_dma_cache_wback_inv;
1464 		_dma_cache_inv		= r4k_dma_cache_inv;
1465 	}
1466 #endif
1467 
1468 	build_clear_page();
1469 	build_copy_page();
1470 #if !defined(CONFIG_MIPS_CMP)
1471 	local_r4k___flush_cache_all(NULL);
1472 #endif
1473 	coherency_setup();
1474 	board_cache_error_setup = r4k_cache_error_setup;
1475 }
1476