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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 = 64 << ((config1 >> 22) & 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 = 64 << ((config1 >> 13) & 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_24K:
1055         case CPU_34K:
1056         case CPU_74K:
1057         case CPU_1004K:
1058                 if ((read_c0_config7() & (1 << 16))) {
1059                         /* effectively physically indexed dcache,
1060                            thus no virtual aliases. */
1061                         c->dcache.flags |= MIPS_CACHE_PINDEX;
1062                         break;
1063                 }
1064         default:
1065                 if (c->dcache.waysize > PAGE_SIZE)
1066                         c->dcache.flags |= MIPS_CACHE_ALIASES;
1067         }
1068
1069         switch (c->cputype) {
1070         case CPU_20KC:
1071                 /*
1072                  * Some older 20Kc chips doesn't have the 'VI' bit in
1073                  * the config register.
1074                  */
1075                 c->icache.flags |= MIPS_CACHE_VTAG;
1076                 break;
1077
1078         case CPU_ALCHEMY:
1079                 c->icache.flags |= MIPS_CACHE_IC_F_DC;
1080                 break;
1081         }
1082
1083 #ifdef  CONFIG_CPU_LOONGSON2
1084         /*
1085          * LOONGSON2 has 4 way icache, but when using indexed cache op,
1086          * one op will act on all 4 ways
1087          */
1088         c->icache.ways = 1;
1089 #endif
1090
1091         printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1092                icache_size >> 10,
1093                c->icache.flags & MIPS_CACHE_VTAG ? "VIVT" : "VIPT",
1094                way_string[c->icache.ways], c->icache.linesz);
1095
1096         printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1097                dcache_size >> 10, way_string[c->dcache.ways],
1098                (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1099                (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1100                         "cache aliases" : "no aliases",
1101                c->dcache.linesz);
1102 }
1103
1104 /*
1105  * If you even _breathe_ on this function, look at the gcc output and make sure
1106  * it does not pop things on and off the stack for the cache sizing loop that
1107  * executes in KSEG1 space or else you will crash and burn badly.  You have
1108  * been warned.
1109  */
1110 static int __cpuinit probe_scache(void)
1111 {
1112         unsigned long flags, addr, begin, end, pow2;
1113         unsigned int config = read_c0_config();
1114         struct cpuinfo_mips *c = &current_cpu_data;
1115
1116         if (config & CONF_SC)
1117                 return 0;
1118
1119         begin = (unsigned long) &_stext;
1120         begin &= ~((4 * 1024 * 1024) - 1);
1121         end = begin + (4 * 1024 * 1024);
1122
1123         /*
1124          * This is such a bitch, you'd think they would make it easy to do
1125          * this.  Away you daemons of stupidity!
1126          */
1127         local_irq_save(flags);
1128
1129         /* Fill each size-multiple cache line with a valid tag. */
1130         pow2 = (64 * 1024);
1131         for (addr = begin; addr < end; addr = (begin + pow2)) {
1132                 unsigned long *p = (unsigned long *) addr;
1133                 __asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1134                 pow2 <<= 1;
1135         }
1136
1137         /* Load first line with zero (therefore invalid) tag. */
1138         write_c0_taglo(0);
1139         write_c0_taghi(0);
1140         __asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1141         cache_op(Index_Store_Tag_I, begin);
1142         cache_op(Index_Store_Tag_D, begin);
1143         cache_op(Index_Store_Tag_SD, begin);
1144
1145         /* Now search for the wrap around point. */
1146         pow2 = (128 * 1024);
1147         for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1148                 cache_op(Index_Load_Tag_SD, addr);
1149                 __asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1150                 if (!read_c0_taglo())
1151                         break;
1152                 pow2 <<= 1;
1153         }
1154         local_irq_restore(flags);
1155         addr -= begin;
1156
1157         scache_size = addr;
1158         c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1159         c->scache.ways = 1;
1160         c->dcache.waybit = 0;           /* does not matter */
1161
1162         return 1;
1163 }
1164
1165 #if defined(CONFIG_CPU_LOONGSON2)
1166 static void __init loongson2_sc_init(void)
1167 {
1168         struct cpuinfo_mips *c = &current_cpu_data;
1169
1170         scache_size = 512*1024;
1171         c->scache.linesz = 32;
1172         c->scache.ways = 4;
1173         c->scache.waybit = 0;
1174         c->scache.waysize = scache_size / (c->scache.ways);
1175         c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1176         pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1177                scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1178
1179         c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1180 }
1181 #endif
1182
1183 extern int r5k_sc_init(void);
1184 extern int rm7k_sc_init(void);
1185 extern int mips_sc_init(void);
1186
1187 static void __cpuinit setup_scache(void)
1188 {
1189         struct cpuinfo_mips *c = &current_cpu_data;
1190         unsigned int config = read_c0_config();
1191         int sc_present = 0;
1192
1193         /*
1194          * Do the probing thing on R4000SC and R4400SC processors.  Other
1195          * processors don't have a S-cache that would be relevant to the
1196          * Linux memory management.
1197          */
1198         switch (c->cputype) {
1199         case CPU_R4000SC:
1200         case CPU_R4000MC:
1201         case CPU_R4400SC:
1202         case CPU_R4400MC:
1203                 sc_present = run_uncached(probe_scache);
1204                 if (sc_present)
1205                         c->options |= MIPS_CPU_CACHE_CDEX_S;
1206                 break;
1207
1208         case CPU_R10000:
1209         case CPU_R12000:
1210         case CPU_R14000:
1211                 scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1212                 c->scache.linesz = 64 << ((config >> 13) & 1);
1213                 c->scache.ways = 2;
1214                 c->scache.waybit= 0;
1215                 sc_present = 1;
1216                 break;
1217
1218         case CPU_R5000:
1219         case CPU_NEVADA:
1220 #ifdef CONFIG_R5000_CPU_SCACHE
1221                 r5k_sc_init();
1222 #endif
1223                 return;
1224
1225         case CPU_RM7000:
1226         case CPU_RM9000:
1227 #ifdef CONFIG_RM7000_CPU_SCACHE
1228                 rm7k_sc_init();
1229 #endif
1230                 return;
1231
1232 #if defined(CONFIG_CPU_LOONGSON2)
1233         case CPU_LOONGSON2:
1234                 loongson2_sc_init();
1235                 return;
1236 #endif
1237         case CPU_XLP:
1238                 /* don't need to worry about L2, fully coherent */
1239                 return;
1240
1241         default:
1242                 if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
1243                     c->isa_level == MIPS_CPU_ISA_M32R2 ||
1244                     c->isa_level == MIPS_CPU_ISA_M64R1 ||
1245                     c->isa_level == MIPS_CPU_ISA_M64R2) {
1246 #ifdef CONFIG_MIPS_CPU_SCACHE
1247                         if (mips_sc_init ()) {
1248                                 scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1249                                 printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1250                                        scache_size >> 10,
1251                                        way_string[c->scache.ways], c->scache.linesz);
1252                         }
1253 #else
1254                         if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1255                                 panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1256 #endif
1257                         return;
1258                 }
1259                 sc_present = 0;
1260         }
1261
1262         if (!sc_present)
1263                 return;
1264
1265         /* compute a couple of other cache variables */
1266         c->scache.waysize = scache_size / c->scache.ways;
1267
1268         c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1269
1270         printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1271                scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1272
1273         c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1274 }
1275
1276 void au1x00_fixup_config_od(void)
1277 {
1278         /*
1279          * c0_config.od (bit 19) was write only (and read as 0)
1280          * on the early revisions of Alchemy SOCs.  It disables the bus
1281          * transaction overlapping and needs to be set to fix various errata.
1282          */
1283         switch (read_c0_prid()) {
1284         case 0x00030100: /* Au1000 DA */
1285         case 0x00030201: /* Au1000 HA */
1286         case 0x00030202: /* Au1000 HB */
1287         case 0x01030200: /* Au1500 AB */
1288         /*
1289          * Au1100 errata actually keeps silence about this bit, so we set it
1290          * just in case for those revisions that require it to be set according
1291          * to the (now gone) cpu table.
1292          */
1293         case 0x02030200: /* Au1100 AB */
1294         case 0x02030201: /* Au1100 BA */
1295         case 0x02030202: /* Au1100 BC */
1296                 set_c0_config(1 << 19);
1297                 break;
1298         }
1299 }
1300
1301 /* CP0 hazard avoidance. */
1302 #define NXP_BARRIER()                                                   \
1303          __asm__ __volatile__(                                          \
1304         ".set noreorder\n\t"                                            \
1305         "nop; nop; nop; nop; nop; nop;\n\t"                             \
1306         ".set reorder\n\t")
1307
1308 static void nxp_pr4450_fixup_config(void)
1309 {
1310         unsigned long config0;
1311
1312         config0 = read_c0_config();
1313
1314         /* clear all three cache coherency fields */
1315         config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1316         config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1317                     ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1318                     ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1319         write_c0_config(config0);
1320         NXP_BARRIER();
1321 }
1322
1323 static int __cpuinitdata cca = -1;
1324
1325 static int __init cca_setup(char *str)
1326 {
1327         get_option(&str, &cca);
1328
1329         return 1;
1330 }
1331
1332 __setup("cca=", cca_setup);
1333
1334 static void __cpuinit coherency_setup(void)
1335 {
1336         if (cca < 0 || cca > 7)
1337                 cca = read_c0_config() & CONF_CM_CMASK;
1338         _page_cachable_default = cca << _CACHE_SHIFT;
1339
1340         pr_debug("Using cache attribute %d\n", cca);
1341         change_c0_config(CONF_CM_CMASK, cca);
1342
1343         /*
1344          * c0_status.cu=0 specifies that updates by the sc instruction use
1345          * the coherency mode specified by the TLB; 1 means cachable
1346          * coherent update on write will be used.  Not all processors have
1347          * this bit and; some wire it to zero, others like Toshiba had the
1348          * silly idea of putting something else there ...
1349          */
1350         switch (current_cpu_type()) {
1351         case CPU_R4000PC:
1352         case CPU_R4000SC:
1353         case CPU_R4000MC:
1354         case CPU_R4400PC:
1355         case CPU_R4400SC:
1356         case CPU_R4400MC:
1357                 clear_c0_config(CONF_CU);
1358                 break;
1359         /*
1360          * We need to catch the early Alchemy SOCs with
1361          * the write-only co_config.od bit and set it back to one on:
1362          * Au1000 rev DA, HA, HB;  Au1100 AB, BA, BC, Au1500 AB
1363          */
1364         case CPU_ALCHEMY:
1365                 au1x00_fixup_config_od();
1366                 break;
1367
1368         case PRID_IMP_PR4450:
1369                 nxp_pr4450_fixup_config();
1370                 break;
1371         }
1372 }
1373
1374 #if defined(CONFIG_DMA_NONCOHERENT)
1375
1376 static int __cpuinitdata coherentio;
1377
1378 static int __init setcoherentio(char *str)
1379 {
1380         coherentio = 1;
1381
1382         return 1;
1383 }
1384
1385 __setup("coherentio", setcoherentio);
1386 #endif
1387
1388 static void __cpuinit r4k_cache_error_setup(void)
1389 {
1390         extern char __weak except_vec2_generic;
1391         extern char __weak except_vec2_sb1;
1392         struct cpuinfo_mips *c = &current_cpu_data;
1393
1394         switch (c->cputype) {
1395         case CPU_SB1:
1396         case CPU_SB1A:
1397                 set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1398                 break;
1399
1400         default:
1401                 set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1402                 break;
1403         }
1404 }
1405
1406 void __cpuinit r4k_cache_init(void)
1407 {
1408         extern void build_clear_page(void);
1409         extern void build_copy_page(void);
1410         struct cpuinfo_mips *c = &current_cpu_data;
1411
1412         probe_pcache();
1413         setup_scache();
1414
1415         r4k_blast_dcache_page_setup();
1416         r4k_blast_dcache_page_indexed_setup();
1417         r4k_blast_dcache_setup();
1418         r4k_blast_icache_page_setup();
1419         r4k_blast_icache_page_indexed_setup();
1420         r4k_blast_icache_setup();
1421         r4k_blast_scache_page_setup();
1422         r4k_blast_scache_page_indexed_setup();
1423         r4k_blast_scache_setup();
1424
1425         /*
1426          * Some MIPS32 and MIPS64 processors have physically indexed caches.
1427          * This code supports virtually indexed processors and will be
1428          * unnecessarily inefficient on physically indexed processors.
1429          */
1430         if (c->dcache.linesz)
1431                 shm_align_mask = max_t( unsigned long,
1432                                         c->dcache.sets * c->dcache.linesz - 1,
1433                                         PAGE_SIZE - 1);
1434         else
1435                 shm_align_mask = PAGE_SIZE-1;
1436
1437         __flush_cache_vmap      = r4k__flush_cache_vmap;
1438         __flush_cache_vunmap    = r4k__flush_cache_vunmap;
1439
1440         flush_cache_all         = cache_noop;
1441         __flush_cache_all       = r4k___flush_cache_all;
1442         flush_cache_mm          = r4k_flush_cache_mm;
1443         flush_cache_page        = r4k_flush_cache_page;
1444         flush_cache_range       = r4k_flush_cache_range;
1445
1446         __flush_kernel_vmap_range = r4k_flush_kernel_vmap_range;
1447
1448         flush_cache_sigtramp    = r4k_flush_cache_sigtramp;
1449         flush_icache_all        = r4k_flush_icache_all;
1450         local_flush_data_cache_page     = local_r4k_flush_data_cache_page;
1451         flush_data_cache_page   = r4k_flush_data_cache_page;
1452         flush_icache_range      = r4k_flush_icache_range;
1453         local_flush_icache_range        = local_r4k_flush_icache_range;
1454
1455 #if defined(CONFIG_DMA_NONCOHERENT)
1456         if (coherentio) {
1457                 _dma_cache_wback_inv    = (void *)cache_noop;
1458                 _dma_cache_wback        = (void *)cache_noop;
1459                 _dma_cache_inv          = (void *)cache_noop;
1460         } else {
1461                 _dma_cache_wback_inv    = r4k_dma_cache_wback_inv;
1462                 _dma_cache_wback        = r4k_dma_cache_wback_inv;
1463                 _dma_cache_inv          = r4k_dma_cache_inv;
1464         }
1465 #endif
1466
1467         build_clear_page();
1468         build_copy_page();
1469 #if !defined(CONFIG_MIPS_CMP)
1470         local_r4k___flush_cache_all(NULL);
1471 #endif
1472         coherency_setup();
1473         board_cache_error_setup = r4k_cache_error_setup;
1474 }