1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
7  * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  */
10 #include <linux/config.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/mm.h>
15 #include <linux/bitops.h>
16 
17 #include <asm/bcache.h>
18 #include <asm/bootinfo.h>
19 #include <asm/cacheops.h>
20 #include <asm/cpu.h>
21 #include <asm/io.h>
22 #include <asm/page.h>
23 #include <asm/pgtable.h>
24 #include <asm/r4kcache.h>
25 #include <asm/system.h>
26 #include <asm/mmu_context.h>
27 #include <asm/war.h>
28 
29 static unsigned long icache_size, dcache_size, scache_size;
30 
31 /*
32  * Dummy cache handling routines for machines without boardcaches
33  */
no_sc_noop(void)34 static void no_sc_noop(void) {}
35 
36 static struct bcache_ops no_sc_ops = {
37 	.bc_enable = (void *)no_sc_noop,
38 	.bc_disable = (void *)no_sc_noop,
39 	.bc_wback_inv = (void *)no_sc_noop,
40 	.bc_inv = (void *)no_sc_noop
41 };
42 
43 struct bcache_ops *bcops = &no_sc_ops;
44 
45 #define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x2010)
46 #define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x2020)
47 
48 #define R4600_HIT_CACHEOP_WAR_IMPL					\
49 do {									\
50 	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
51 		*(volatile unsigned long *)KSEG1;			\
52 	if (R4600_V1_HIT_CACHEOP_WAR)					\
53 		__asm__ __volatile__("nop;nop;nop;nop");		\
54 } while (0)
55 
56 static void (* r4k_blast_dcache_page)(unsigned long addr);
57 
r4k_blast_dcache_page_dc32(unsigned long addr)58 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
59 {
60 	R4600_HIT_CACHEOP_WAR_IMPL;
61 	blast_dcache32_page(addr);
62 }
63 
r4k_blast_dcache_page_setup(void)64 static inline void r4k_blast_dcache_page_setup(void)
65 {
66 	unsigned long dc_lsize = current_cpu_data.dcache.linesz;
67 
68 	if (dc_lsize == 16)
69 		r4k_blast_dcache_page = blast_dcache16_page;
70 	else if (dc_lsize == 32)
71 		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
72 }
73 
74 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
75 
r4k_blast_dcache_page_indexed_setup(void)76 static void r4k_blast_dcache_page_indexed_setup(void)
77 {
78 	unsigned long dc_lsize = current_cpu_data.dcache.linesz;
79 
80 	if (dc_lsize == 16)
81 		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
82 	else if (dc_lsize == 32)
83 		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
84 }
85 
86 static void (* r4k_blast_dcache)(void);
87 
r4k_blast_dcache_setup(void)88 static inline void r4k_blast_dcache_setup(void)
89 {
90 	unsigned long dc_lsize = current_cpu_data.dcache.linesz;
91 
92 	if (dc_lsize == 16)
93 		r4k_blast_dcache = blast_dcache16;
94 	else if (dc_lsize == 32)
95 		r4k_blast_dcache = blast_dcache32;
96 }
97 
98 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
99 #define JUMP_TO_ALIGN(order) \
100 	__asm__ __volatile__( \
101 		"b\t1f\n\t" \
102 		".align\t" #order "\n\t" \
103 		"1:\n\t" \
104 		)
105 #define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
106 #define CACHE32_UNROLL32_ALIGN2	JUMP_TO_ALIGN(11)
107 
blast_r4600_v1_icache32(void)108 static inline void blast_r4600_v1_icache32(void)
109 {
110 	unsigned long flags;
111 
112 	local_irq_save(flags);
113 	blast_icache32();
114 	local_irq_restore(flags);
115 }
116 
tx49_blast_icache32(void)117 static inline void tx49_blast_icache32(void)
118 {
119 	unsigned long start = KSEG0;
120 	unsigned long end = start + current_cpu_data.icache.waysize;
121 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
122 	unsigned long ws_end = current_cpu_data.icache.ways <<
123 	                       current_cpu_data.icache.waybit;
124 	unsigned long ws, addr;
125 
126 	CACHE32_UNROLL32_ALIGN2;
127 	/* I'm in even chunk.  blast odd chunks */
128 	for (ws = 0; ws < ws_end; ws += ws_inc)
129 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
130 			cache32_unroll32(addr|ws,Index_Invalidate_I);
131 	CACHE32_UNROLL32_ALIGN;
132 	/* I'm in odd chunk.  blast even chunks */
133 	for (ws = 0; ws < ws_end; ws += ws_inc)
134 		for (addr = start; addr < end; addr += 0x400 * 2)
135 			cache32_unroll32(addr|ws,Index_Invalidate_I);
136 }
137 
blast_icache32_r4600_v1_page_indexed(unsigned long page)138 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
139 {
140 	unsigned long flags;
141 
142 	local_irq_save(flags);
143 	blast_icache32_page_indexed(page);
144 	local_irq_restore(flags);
145 }
146 
tx49_blast_icache32_page_indexed(unsigned long page)147 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
148 {
149 	unsigned long start = page;
150 	unsigned long end = start + PAGE_SIZE;
151 	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
152 	unsigned long ws_end = current_cpu_data.icache.ways <<
153 	                       current_cpu_data.icache.waybit;
154 	unsigned long ws, addr;
155 
156 	CACHE32_UNROLL32_ALIGN2;
157 	/* I'm in even chunk.  blast odd chunks */
158 	for (ws = 0; ws < ws_end; ws += ws_inc)
159 		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
160 			cache32_unroll32(addr|ws,Index_Invalidate_I);
161 	CACHE32_UNROLL32_ALIGN;
162 	/* I'm in odd chunk.  blast even chunks */
163 	for (ws = 0; ws < ws_end; ws += ws_inc)
164 		for (addr = start; addr < end; addr += 0x400 * 2)
165 			cache32_unroll32(addr|ws,Index_Invalidate_I);
166 }
167 
168 static void (* r4k_blast_icache_page)(unsigned long addr);
169 
r4k_blast_icache_page_setup(void)170 static inline void r4k_blast_icache_page_setup(void)
171 {
172 	unsigned long ic_lsize = current_cpu_data.icache.linesz;
173 
174 	if (ic_lsize == 16)
175 		r4k_blast_icache_page = blast_icache16_page;
176 	else if (ic_lsize == 32)
177 		r4k_blast_icache_page = blast_icache32_page;
178 	else if (ic_lsize == 64)
179 		r4k_blast_icache_page = blast_icache64_page;
180 }
181 
182 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
183 
r4k_blast_icache_page_indexed_setup(void)184 static inline void r4k_blast_icache_page_indexed_setup(void)
185 {
186 	unsigned long ic_lsize = current_cpu_data.icache.linesz;
187 
188 	if (ic_lsize == 16)
189 		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
190 	else if (ic_lsize == 32) {
191 		if (TX49XX_ICACHE_INDEX_INV_WAR)
192 			r4k_blast_icache_page_indexed =
193 				tx49_blast_icache32_page_indexed;
194 		else if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
195 			r4k_blast_icache_page_indexed =
196 				blast_icache32_r4600_v1_page_indexed;
197 		else
198 			r4k_blast_icache_page_indexed =
199 				blast_icache32_page_indexed;
200 	} else if (ic_lsize == 64)
201 		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
202 }
203 
204 static void (* r4k_blast_icache)(void);
205 
r4k_blast_icache_setup(void)206 static inline void r4k_blast_icache_setup(void)
207 {
208 	unsigned long ic_lsize = current_cpu_data.icache.linesz;
209 
210 	if (ic_lsize == 16)
211 		r4k_blast_icache = blast_icache16;
212 	else if (ic_lsize == 32) {
213 		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
214 			r4k_blast_icache = blast_r4600_v1_icache32;
215 		else if (TX49XX_ICACHE_INDEX_INV_WAR)
216 			r4k_blast_icache = tx49_blast_icache32;
217 		else if (ic_lsize == 32)
218 			r4k_blast_icache = blast_icache32;
219 	} else if (ic_lsize == 64)
220 		r4k_blast_icache = blast_icache64;
221 }
222 
223 static void (* r4k_blast_scache_page)(unsigned long addr);
224 
r4k_blast_scache_page_setup(void)225 static inline void r4k_blast_scache_page_setup(void)
226 {
227 	unsigned long sc_lsize = current_cpu_data.scache.linesz;
228 
229 	if (sc_lsize == 16)
230 		r4k_blast_scache_page = blast_scache16_page;
231 	else if (sc_lsize == 32)
232 		r4k_blast_scache_page = blast_scache32_page;
233 	else if (sc_lsize == 64)
234 		r4k_blast_scache_page = blast_scache64_page;
235 	else if (sc_lsize == 128)
236 		r4k_blast_scache_page = blast_scache128_page;
237 }
238 
239 static void (* r4k_blast_scache)(void);
240 
r4k_blast_scache_setup(void)241 static inline void r4k_blast_scache_setup(void)
242 {
243 	unsigned long sc_lsize = current_cpu_data.scache.linesz;
244 
245 	if (sc_lsize == 16)
246 		r4k_blast_scache = blast_scache16;
247 	else if (sc_lsize == 32)
248 		r4k_blast_scache = blast_scache32;
249 	else if (sc_lsize == 64)
250 		r4k_blast_scache = blast_scache64;
251 	else if (sc_lsize == 128)
252 		r4k_blast_scache = blast_scache128;
253 }
254 
r4k_flush_cache_all(void)255 static void r4k_flush_cache_all(void)
256 {
257 	if (!cpu_has_dc_aliases)
258 		return;
259 
260 	r4k_blast_dcache();
261 	r4k_blast_icache();
262 }
263 
r4k___flush_cache_all(void)264 static void r4k___flush_cache_all(void)
265 {
266 	r4k_blast_dcache();
267 	r4k_blast_icache();
268 
269 	switch (current_cpu_data.cputype) {
270 	case CPU_R4000SC:
271 	case CPU_R4000MC:
272 	case CPU_R4400SC:
273 	case CPU_R4400MC:
274 	case CPU_R10000:
275 	case CPU_R12000:
276 		r4k_blast_scache();
277 	}
278 }
279 
r4k_flush_cache_range(struct mm_struct * mm,unsigned long start,unsigned long end)280 static void r4k_flush_cache_range(struct mm_struct *mm,
281 	unsigned long start, unsigned long end)
282 {
283 	if (!cpu_has_dc_aliases)
284 		return;
285 
286 	if (cpu_context(smp_processor_id(), mm) != 0) {
287 		r4k_blast_dcache();
288 		r4k_blast_icache();
289 	}
290 }
291 
r4k_flush_cache_mm(struct mm_struct * mm)292 static void r4k_flush_cache_mm(struct mm_struct *mm)
293 {
294 	if (!cpu_has_dc_aliases)
295 		return;
296 
297 	if (!cpu_context(smp_processor_id(), mm))
298 		return;
299 
300 	r4k_blast_dcache();
301 	r4k_blast_icache();
302 
303 	/*
304 	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
305 	 * only flush the primary caches but R10000 and R12000 behave sane ...
306 	 */
307 	if (current_cpu_data.cputype == CPU_R4000SC ||
308 	    current_cpu_data.cputype == CPU_R4000MC ||
309 	    current_cpu_data.cputype == CPU_R4400SC ||
310 	    current_cpu_data.cputype == CPU_R4400MC)
311 		r4k_blast_scache();
312 }
313 
r4k_flush_cache_page(struct vm_area_struct * vma,unsigned long page)314 static void r4k_flush_cache_page(struct vm_area_struct *vma,
315 					unsigned long page)
316 {
317 	int exec = vma->vm_flags & VM_EXEC;
318 	struct mm_struct *mm = vma->vm_mm;
319 	pgd_t *pgdp;
320 	pmd_t *pmdp;
321 	pte_t *ptep;
322 
323 	/*
324 	 * If ownes no valid ASID yet, cannot possibly have gotten
325 	 * this page into the cache.
326 	 */
327 	if (cpu_context(smp_processor_id(), mm) == 0)
328 		return;
329 
330 	page &= PAGE_MASK;
331 	pgdp = pgd_offset(mm, page);
332 	pmdp = pmd_offset(pgdp, page);
333 	ptep = pte_offset(pmdp, page);
334 
335 	/*
336 	 * If the page isn't marked valid, the page cannot possibly be
337 	 * in the cache.
338 	 */
339 	if (!(pte_val(*ptep) & _PAGE_PRESENT))
340 		return;
341 
342 	/*
343 	 * Doing flushes for another ASID than the current one is
344 	 * too difficult since stupid R4k caches do a TLB translation
345 	 * for every cache flush operation.  So we do indexed flushes
346 	 * in that case, which doesn't overly flush the cache too much.
347 	 */
348 	if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID)) {
349 		if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
350 			r4k_blast_dcache_page(page);
351 		if (exec)
352 			r4k_blast_icache_page(page);
353 
354 		return;
355 	}
356 
357 	/*
358 	 * Do indexed flush, too much work to get the (possible) TLB refills
359 	 * to work correctly.
360 	 */
361 	page = (KSEG0 + (page & (dcache_size - 1)));
362 	if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
363 		r4k_blast_dcache_page_indexed(page);
364 	if (exec) {
365 		if (cpu_has_vtag_icache) {
366 			int cpu = smp_processor_id();
367 
368 			if (cpu_context(cpu, vma->vm_mm) != 0)
369 				drop_mmu_context(vma->vm_mm, cpu);
370 		} else
371 			r4k_blast_icache_page_indexed(page);
372 	}
373 }
374 
r4k_flush_data_cache_page(unsigned long addr)375 static void r4k_flush_data_cache_page(unsigned long addr)
376 {
377 	r4k_blast_dcache_page(addr);
378 }
379 
r4k_flush_icache_range(unsigned long start,unsigned long end)380 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
381 {
382 	unsigned long dc_lsize = current_cpu_data.dcache.linesz;
383 	unsigned long ic_lsize = current_cpu_data.icache.linesz;
384 	unsigned long addr, aend;
385 
386 	if (!cpu_has_ic_fills_f_dc) {
387 		if (end - start > dcache_size)
388 			r4k_blast_dcache();
389 		else {
390 			addr = start & ~(dc_lsize - 1);
391 			aend = (end - 1) & ~(dc_lsize - 1);
392 
393 			while (1) {
394 				/* Hit_Writeback_Inv_D */
395 				protected_writeback_dcache_line(addr);
396 				if (addr == aend)
397 					break;
398 				addr += dc_lsize;
399 			}
400 		}
401 	}
402 
403 	if (end - start > icache_size)
404 		r4k_blast_icache();
405 	else {
406 		addr = start & ~(ic_lsize - 1);
407 		aend = (end - 1) & ~(ic_lsize - 1);
408 		while (1) {
409 			/* Hit_Invalidate_I */
410 			protected_flush_icache_line(addr);
411 			if (addr == aend)
412 				break;
413 			addr += ic_lsize;
414 		}
415 	}
416 }
417 
418 /*
419  * Ok, this seriously sucks.  We use them to flush a user page but don't
420  * know the virtual address, so we have to blast away the whole icache
421  * which is significantly more expensive than the real thing.  Otoh we at
422  * least know the kernel address of the page so we can flush it
423  * selectivly.
424  */
r4k_flush_icache_page(struct vm_area_struct * vma,struct page * page)425 static void r4k_flush_icache_page(struct vm_area_struct *vma,
426 	struct page *page)
427 {
428 	/*
429 	 * If there's no context yet, or the page isn't executable, no icache
430 	 * flush is needed.
431 	 */
432 	if (!(vma->vm_flags & VM_EXEC))
433 		return;
434 
435 	/*
436 	 * Tricky ...  Because we don't know the virtual address we've got the
437 	 * choice of either invalidating the entire primary and secondary
438 	 * caches or invalidating the secondary caches also.  With the subset
439 	 * enforcment on R4000SC, R4400SC, R10000 and R12000 invalidating the
440 	 * secondary cache will result in any entries in the primary caches
441 	 * also getting invalidated which hopefully is a bit more economical.
442 	 */
443 	if (cpu_has_subset_pcaches) {
444 		unsigned long addr = (unsigned long) page_address(page);
445 
446 		r4k_blast_scache_page(addr);
447 		ClearPageDcacheDirty(page);
448 
449 		return;
450 	}
451 
452 	if (!cpu_has_ic_fills_f_dc) {
453 		unsigned long addr = (unsigned long) page_address(page);
454 		r4k_blast_dcache_page(addr);
455 		ClearPageDcacheDirty(page);
456 	}
457 
458 	/*
459 	 * We're not sure of the virtual address(es) involved here, so
460 	 * we have to flush the entire I-cache.
461 	 */
462 	if (cpu_has_vtag_icache) {
463 		int cpu = smp_processor_id();
464 
465 		if (cpu_context(cpu, vma->vm_mm) != 0)
466 			drop_mmu_context(vma->vm_mm, cpu);
467 	} else
468 		r4k_blast_icache();
469 }
470 
471 #ifdef CONFIG_NONCOHERENT_IO
472 
r4k_dma_cache_wback_inv(unsigned long addr,unsigned long size)473 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
474 {
475 	unsigned long end, a;
476 
477 	/* Catch bad driver code */
478 	BUG_ON(size == 0);
479 
480 	if (cpu_has_subset_pcaches) {
481 		unsigned long sc_lsize = current_cpu_data.scache.linesz;
482 
483 		if (size >= scache_size) {
484 			r4k_blast_scache();
485 			return;
486 		}
487 
488 		a = addr & ~(sc_lsize - 1);
489 		end = (addr + size - 1) & ~(sc_lsize - 1);
490 		while (1) {
491 			flush_scache_line(a);	/* Hit_Writeback_Inv_SD */
492 			if (a == end)
493 				break;
494 			a += sc_lsize;
495 		}
496 		return;
497 	}
498 
499 	/*
500 	 * Either no secondary cache or the available caches don't have the
501 	 * subset property so we have to flush the primary caches
502 	 * explicitly
503 	 */
504 	if (size >= dcache_size) {
505 		r4k_blast_dcache();
506 	} else {
507 		unsigned long dc_lsize = current_cpu_data.dcache.linesz;
508 
509 		R4600_HIT_CACHEOP_WAR_IMPL;
510 		a = addr & ~(dc_lsize - 1);
511 		end = (addr + size - 1) & ~(dc_lsize - 1);
512 		while (1) {
513 			flush_dcache_line(a);	/* Hit_Writeback_Inv_D */
514 			if (a == end)
515 				break;
516 			a += dc_lsize;
517 		}
518 	}
519 
520 	bc_wback_inv(addr, size);
521 }
522 
r4k_dma_cache_inv(unsigned long addr,unsigned long size)523 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
524 {
525 	unsigned long end, a;
526 
527 	/* Catch bad driver code */
528 	BUG_ON(size == 0);
529 
530 	if (cpu_has_subset_pcaches) {
531 		unsigned long sc_lsize = current_cpu_data.scache.linesz;
532 
533 		if (size >= scache_size) {
534 			r4k_blast_scache();
535 			return;
536 		}
537 
538 		a = addr & ~(sc_lsize - 1);
539 		end = (addr + size - 1) & ~(sc_lsize - 1);
540 		while (1) {
541 			flush_scache_line(a);	/* Hit_Writeback_Inv_SD */
542 			if (a == end)
543 				break;
544 			a += sc_lsize;
545 		}
546 		return;
547 	}
548 
549 	if (size >= dcache_size) {
550 		r4k_blast_dcache();
551 	} else {
552 		unsigned long dc_lsize = current_cpu_data.dcache.linesz;
553 
554 		R4600_HIT_CACHEOP_WAR_IMPL;
555 		a = addr & ~(dc_lsize - 1);
556 		end = (addr + size - 1) & ~(dc_lsize - 1);
557 		while (1) {
558 			flush_dcache_line(a);	/* Hit_Writeback_Inv_D */
559 			if (a == end)
560 				break;
561 			a += dc_lsize;
562 		}
563 	}
564 
565 	bc_inv(addr, size);
566 }
567 #endif /* CONFIG_NONCOHERENT_IO */
568 
569 /*
570  * While we're protected against bad userland addresses we don't care
571  * very much about what happens in that case.  Usually a segmentation
572  * fault will dump the process later on anyway ...
573  */
r4k_flush_cache_sigtramp(unsigned long addr)574 static void r4k_flush_cache_sigtramp(unsigned long addr)
575 {
576 	unsigned long ic_lsize = current_cpu_data.icache.linesz;
577 	unsigned long dc_lsize = current_cpu_data.dcache.linesz;
578 
579 	R4600_HIT_CACHEOP_WAR_IMPL;
580 	protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
581 	protected_flush_icache_line(addr & ~(ic_lsize - 1));
582 	if (MIPS4K_ICACHE_REFILL_WAR) {
583 		__asm__ __volatile__ (
584 			".set push\n\t"
585 			".set noat\n\t"
586 			".set mips3\n\t"
587 #if CONFIG_MIPS32
588 			"la	$at,1f\n\t"
589 #endif
590 #if CONFIG_MIPS64
591 			"dla	$at,1f\n\t"
592 #endif
593 			"cache	%0,($at)\n\t"
594 			"nop; nop; nop\n"
595 			"1:\n\t"
596 			".set pop"
597 			:
598 			: "i" (Hit_Invalidate_I));
599 	}
600 	if (MIPS_CACHE_SYNC_WAR)
601 		__asm__ __volatile__ ("sync");
602 }
603 
r4k_flush_icache_all(void)604 static void r4k_flush_icache_all(void)
605 {
606 	if (cpu_has_vtag_icache)
607 		r4k_blast_icache();
608 }
609 
rm7k_erratum31(void)610 static inline void rm7k_erratum31(void)
611 {
612 	const unsigned long ic_lsize = 32;
613 	unsigned long addr;
614 
615 	/* RM7000 erratum #31. The icache is screwed at startup. */
616 	write_c0_taglo(0);
617 	write_c0_taghi(0);
618 
619 	for (addr = KSEG0; addr <= KSEG0 + 4096; addr += ic_lsize) {
620 		__asm__ __volatile__ (
621 			".set noreorder\n\t"
622 			".set mips3\n\t"
623 			"cache\t%1, 0(%0)\n\t"
624 			"cache\t%1, 0x1000(%0)\n\t"
625 			"cache\t%1, 0x2000(%0)\n\t"
626 			"cache\t%1, 0x3000(%0)\n\t"
627 			"cache\t%2, 0(%0)\n\t"
628 			"cache\t%2, 0x1000(%0)\n\t"
629 			"cache\t%2, 0x2000(%0)\n\t"
630 			"cache\t%2, 0x3000(%0)\n\t"
631 			"cache\t%1, 0(%0)\n\t"
632 			"cache\t%1, 0x1000(%0)\n\t"
633 			"cache\t%1, 0x2000(%0)\n\t"
634 			"cache\t%1, 0x3000(%0)\n\t"
635 			".set\tmips0\n\t"
636 			".set\treorder\n\t"
637 			:
638 			: "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
639 	}
640 }
641 
642 static char *way_string[] = { NULL, "direct mapped", "2-way", "3-way", "4-way",
643 	"5-way", "6-way", "7-way", "8-way"
644 };
645 
probe_pcache(void)646 static void __init probe_pcache(void)
647 {
648 	struct cpuinfo_mips *c = &current_cpu_data;
649 	unsigned int config = read_c0_config();
650 	unsigned int prid = read_c0_prid();
651 	unsigned long config1;
652 	unsigned int lsize;
653 
654 	switch (c->cputype) {
655 	case CPU_R4600:			/* QED style two way caches? */
656 	case CPU_R4700:
657 	case CPU_R5000:
658 	case CPU_NEVADA:
659 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
660 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
661 		c->icache.ways = 2;
662 		c->icache.waybit = ffs(icache_size/2) - 1;
663 
664 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
665 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
666 		c->dcache.ways = 2;
667 		c->dcache.waybit= ffs(dcache_size/2) - 1;
668 
669 		c->options |= MIPS_CPU_CACHE_CDEX_P;
670 		break;
671 
672 	case CPU_R5432:
673 	case CPU_R5500:
674 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
675 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
676 		c->icache.ways = 2;
677 		c->icache.waybit= 0;
678 
679 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
680 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
681 		c->dcache.ways = 2;
682 		c->dcache.waybit = 0;
683 
684 		c->options |= MIPS_CPU_CACHE_CDEX_P;
685 		break;
686 
687 	case CPU_TX49XX:
688 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
689 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
690 		c->icache.ways = 4;
691 		c->icache.waybit= 0;
692 
693 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
694 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
695 		c->dcache.ways = 4;
696 		c->dcache.waybit = 0;
697 
698 		c->options |= MIPS_CPU_CACHE_CDEX_P;
699 		break;
700 
701 	case CPU_R4000PC:
702 	case CPU_R4000SC:
703 	case CPU_R4000MC:
704 	case CPU_R4400PC:
705 	case CPU_R4400SC:
706 	case CPU_R4400MC:
707 	case CPU_R4300:
708 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
709 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
710 		c->icache.ways = 1;
711 		c->icache.waybit = 0; 	/* doesn't matter */
712 
713 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
714 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
715 		c->dcache.ways = 1;
716 		c->dcache.waybit = 0;	/* does not matter */
717 
718 		c->options |= MIPS_CPU_CACHE_CDEX_P;
719 		break;
720 
721 	case CPU_R10000:
722 	case CPU_R12000:
723 		icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
724 		c->icache.linesz = 64;
725 		c->icache.ways = 2;
726 		c->icache.waybit = 0;
727 
728 		dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
729 		c->dcache.linesz = 32;
730 		c->dcache.ways = 2;
731 		c->dcache.waybit = 0;
732 
733 		c->options |= MIPS_CPU_PREFETCH;
734 		break;
735 
736 	case CPU_VR4133:
737 		write_c0_config(config & ~CONF_EB);
738 	case CPU_VR4131:
739 		/* Workaround for cache instruction bug of VR4131 */
740 		if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
741 		    c->processor_id == 0x0c82U) {
742 			config &= ~0x00000030U;
743 			config |= 0x00410000U;
744 			write_c0_config(config);
745 		}
746 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
747 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
748 		c->icache.ways = 2;
749 		c->icache.waybit = ffs(icache_size/2) - 1;
750 
751 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
752 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
753 		c->dcache.ways = 2;
754 		c->dcache.waybit = ffs(dcache_size/2) - 1;
755 
756 		c->options |= MIPS_CPU_CACHE_CDEX_P;
757 		break;
758 
759 	case CPU_VR41XX:
760 	case CPU_VR4111:
761 	case CPU_VR4121:
762 	case CPU_VR4122:
763 	case CPU_VR4181:
764 	case CPU_VR4181A:
765 		icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
766 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
767 		c->icache.ways = 1;
768 		c->icache.waybit = 0; 	/* doesn't matter */
769 
770 		dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
771 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
772 		c->dcache.ways = 1;
773 		c->dcache.waybit = 0;	/* does not matter */
774 
775 		c->options |= MIPS_CPU_CACHE_CDEX_P;
776 		break;
777 
778 	case CPU_RM7000:
779 		rm7k_erratum31();
780 
781 	case CPU_RM9000:
782 		icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
783 		c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
784 		c->icache.ways = 4;
785 		c->icache.waybit = ffs(icache_size / c->icache.ways) - 1;
786 
787 		dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
788 		c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
789 		c->dcache.ways = 4;
790 		c->dcache.waybit = ffs(dcache_size / c->dcache.ways) - 1;
791 
792 #if !defined(CONFIG_SMP) || !defined(RM9000_CDEX_SMP_WAR)
793 		c->options |= MIPS_CPU_CACHE_CDEX_P;
794 #endif
795 		c->options |= MIPS_CPU_PREFETCH;
796 		break;
797 
798 	default:
799 		if (!(config & MIPS_CONF_M))
800 			panic("Don't know how to probe P-caches on this cpu.");
801 
802 		/*
803 		 * So we seem to be a MIPS32 or MIPS64 CPU
804 		 * So let's probe the I-cache ...
805 		 */
806 		config1 = read_c0_config1();
807 
808 		if ((lsize = ((config1 >> 19) & 7)))
809 			c->icache.linesz = 2 << lsize;
810 		else
811 			c->icache.linesz = lsize;
812 		c->icache.sets = 64 << ((config1 >> 22) & 7);
813 		c->icache.ways = 1 + ((config1 >> 16) & 7);
814 
815 		icache_size = c->icache.sets *
816 		              c->icache.ways *
817 		              c->icache.linesz;
818 		c->icache.waybit = ffs(icache_size/c->icache.ways) - 1;
819 
820 		if (config & 0x8)		/* VI bit */
821 			c->icache.flags |= MIPS_CACHE_VTAG;
822 
823 		/*
824 		 * Now probe the MIPS32 / MIPS64 data cache.
825 		 */
826 		c->dcache.flags = 0;
827 
828 		if ((lsize = ((config1 >> 10) & 7)))
829 			c->dcache.linesz = 2 << lsize;
830 		else
831 			c->dcache.linesz= lsize;
832 		c->dcache.sets = 64 << ((config1 >> 13) & 7);
833 		c->dcache.ways = 1 + ((config1 >> 7) & 7);
834 
835 		dcache_size = c->dcache.sets *
836 		              c->dcache.ways *
837 		              c->dcache.linesz;
838 		c->dcache.waybit = ffs(dcache_size/c->dcache.ways) - 1;
839 
840 		c->options |= MIPS_CPU_PREFETCH;
841 		break;
842 	}
843 
844 	/*
845 	 * Processor configuration sanity check for the R4000SC erratum
846 	 * #5.  With page sizes larger than 32kB there is no possibility
847 	 * to get a VCE exception anymore so we don't care about this
848 	 * misconfiguration.  The case is rather theoretical anyway;
849 	 * presumably no vendor is shipping his hardware in the "bad"
850 	 * configuration.
851 	 */
852 	if ((prid & 0xff00) == PRID_IMP_R4000 && (prid & 0xff) < 0x40 &&
853 	    !(config & CONF_SC) && c->icache.linesz != 16 &&
854 	    PAGE_SIZE <= 0x8000)
855 		panic("Improper R4000SC processor configuration detected");
856 
857 	/* compute a couple of other cache variables */
858 	c->icache.waysize = icache_size / c->icache.ways;
859 	c->dcache.waysize = dcache_size / c->dcache.ways;
860 
861 	c->icache.sets = icache_size / (c->icache.linesz * c->icache.ways);
862 	c->dcache.sets = dcache_size / (c->dcache.linesz * c->dcache.ways);
863 
864 	/*
865 	 * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
866 	 * 2-way virtually indexed so normally would suffer from aliases.  So
867 	 * normally they'd suffer from aliases but magic in the hardware deals
868 	 * with that for us so we don't need to take care ourselves.
869 	 */
870 	if (c->cputype != CPU_R10000 && c->cputype != CPU_R12000)
871 		if (c->dcache.waysize > PAGE_SIZE)
872 		        c->dcache.flags |= MIPS_CACHE_ALIASES;
873 
874 	switch (c->cputype) {
875 	case CPU_20KC:
876 		/*
877 		 * Some older 20Kc chips doesn't have the 'VI' bit in
878 		 * the config register.
879 		 */
880 		c->icache.flags |= MIPS_CACHE_VTAG;
881 		break;
882 
883 	case CPU_AU1500:
884 		c->icache.flags |= MIPS_CACHE_IC_F_DC;
885 		break;
886 	}
887 
888 	printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
889 	       icache_size >> 10,
890 	       cpu_has_vtag_icache ? "virtually tagged" : "physically tagged",
891 	       way_string[c->icache.ways], c->icache.linesz);
892 
893 	printk("Primary data cache %ldkB, %s, linesize %d bytes.\n",
894 	       dcache_size >> 10, way_string[c->dcache.ways], c->dcache.linesz);
895 }
896 
897 /*
898  * If you even _breathe_ on this function, look at the gcc output and make sure
899  * it does not pop things on and off the stack for the cache sizing loop that
900  * executes in KSEG1 space or else you will crash and burn badly.  You have
901  * been warned.
902  */
probe_scache(void)903 static int __init probe_scache(void)
904 {
905 	extern unsigned long stext;
906 	unsigned long flags, addr, begin, end, pow2;
907 	unsigned int config = read_c0_config();
908 	struct cpuinfo_mips *c = &current_cpu_data;
909 	int tmp;
910 
911 	if (config & CONF_SC)
912 		return 0;
913 
914 	begin = (unsigned long) &stext;
915 	begin &= ~((4 * 1024 * 1024) - 1);
916 	end = begin + (4 * 1024 * 1024);
917 
918 	/*
919 	 * This is such a bitch, you'd think they would make it easy to do
920 	 * this.  Away you daemons of stupidity!
921 	 */
922 	local_irq_save(flags);
923 
924 	/* Fill each size-multiple cache line with a valid tag. */
925 	pow2 = (64 * 1024);
926 	for (addr = begin; addr < end; addr = (begin + pow2)) {
927 		unsigned long *p = (unsigned long *) addr;
928 		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
929 		pow2 <<= 1;
930 	}
931 
932 	/* Load first line with zero (therefore invalid) tag. */
933 	write_c0_taglo(0);
934 	write_c0_taghi(0);
935 	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
936 	cache_op(Index_Store_Tag_I, begin);
937 	cache_op(Index_Store_Tag_D, begin);
938 	cache_op(Index_Store_Tag_SD, begin);
939 
940 	/* Now search for the wrap around point. */
941 	pow2 = (128 * 1024);
942 	tmp = 0;
943 	for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
944 		cache_op(Index_Load_Tag_SD, addr);
945 		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
946 		if (!read_c0_taglo())
947 			break;
948 		pow2 <<= 1;
949 	}
950 	local_irq_restore(flags);
951 	addr -= begin;
952 
953 	scache_size = addr;
954 	c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
955 	c->scache.ways = 1;
956 	c->dcache.waybit = 0;		/* does not matter */
957 
958 	return 1;
959 }
960 
961 typedef int (*probe_func_t)(unsigned long);
962 extern int r5k_sc_init(void);
963 extern int rm7k_sc_init(void);
964 
setup_scache(void)965 static void __init setup_scache(void)
966 {
967 	struct cpuinfo_mips *c = &current_cpu_data;
968 	unsigned int config = read_c0_config();
969 	probe_func_t probe_scache_kseg1;
970 	int sc_present = 0;
971 
972 	/*
973 	 * Do the probing thing on R4000SC and R4400SC processors.  Other
974 	 * processors don't have a S-cache that would be relevant to the
975 	 * Linux memory managment.
976 	 */
977 	switch (c->cputype) {
978 	case CPU_R4000SC:
979 	case CPU_R4000MC:
980 	case CPU_R4400SC:
981 	case CPU_R4400MC:
982 		probe_scache_kseg1 = (probe_func_t) (KSEG1ADDR(&probe_scache));
983 		sc_present = probe_scache_kseg1(config);
984 		if (sc_present)
985 			c->options |= MIPS_CPU_CACHE_CDEX_S;
986 		break;
987 
988 	case CPU_R10000:
989 	case CPU_R12000:
990 		scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
991 		c->scache.linesz = 64 << ((config >> 13) & 1);
992 		c->scache.ways = 2;
993 		c->scache.waybit= 0;
994 		sc_present = 1;
995 		break;
996 
997 	case CPU_R5000:
998 	case CPU_NEVADA:
999 #ifdef CONFIG_R5000_CPU_SCACHE
1000 		r5k_sc_init();
1001 #endif
1002                 return;
1003 
1004 	case CPU_RM7000:
1005 	case CPU_RM9000:
1006 #ifdef CONFIG_RM7000_CPU_SCACHE
1007 		rm7k_sc_init();
1008 #endif
1009 		return;
1010 
1011 	default:
1012 		sc_present = 0;
1013 	}
1014 
1015 	if (!sc_present)
1016 		return;
1017 
1018 	if ((c->isa_level == MIPS_CPU_ISA_M32 ||
1019 	     c->isa_level == MIPS_CPU_ISA_M64) &&
1020 	    !(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1021 		panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1022 
1023 	/* compute a couple of other cache variables */
1024 	c->scache.waysize = scache_size / c->scache.ways;
1025 
1026 	c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1027 
1028 	printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1029 	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1030 
1031 	c->options |= MIPS_CPU_SUBSET_CACHES;
1032 }
1033 
coherency_setup(void)1034 static inline void coherency_setup(void)
1035 {
1036 	change_c0_config(CONF_CM_CMASK, CONF_CM_DEFAULT);
1037 
1038 	/*
1039 	 * c0_status.cu=0 specifies that updates by the sc instruction use
1040 	 * the coherency mode specified by the TLB; 1 means cachable
1041 	 * coherent update on write will be used.  Not all processors have
1042 	 * this bit and; some wire it to zero, others like Toshiba had the
1043 	 * silly idea of putting something else there ...
1044 	 */
1045 	switch (current_cpu_data.cputype) {
1046 	case CPU_R4000PC:
1047 	case CPU_R4000SC:
1048 	case CPU_R4000MC:
1049 	case CPU_R4400PC:
1050 	case CPU_R4400SC:
1051 	case CPU_R4400MC:
1052 		clear_c0_config(CONF_CU);
1053 		break;
1054 	}
1055 
1056 }
1057 
ld_mmu_r4xx0(void)1058 void __init ld_mmu_r4xx0(void)
1059 {
1060 	extern void build_clear_page(void);
1061 	extern void build_copy_page(void);
1062 	extern char except_vec2_generic;
1063 	struct cpuinfo_mips *c = &current_cpu_data;
1064 
1065 	/* Default cache error handler for R4000 and R5000 family */
1066 	memcpy((void *)(KSEG0 + 0x100), &except_vec2_generic, 0x80);
1067 	memcpy((void *)(KSEG1 + 0x100), &except_vec2_generic, 0x80);
1068 
1069 	probe_pcache();
1070 	setup_scache();
1071 
1072 	if (c->dcache.sets * c->dcache.ways > PAGE_SIZE)
1073 		c->dcache.flags |= MIPS_CACHE_ALIASES;
1074 
1075 	r4k_blast_dcache_page_setup();
1076 	r4k_blast_dcache_page_indexed_setup();
1077 	r4k_blast_dcache_setup();
1078 	r4k_blast_icache_page_setup();
1079 	r4k_blast_icache_page_indexed_setup();
1080 	r4k_blast_icache_setup();
1081 	r4k_blast_scache_page_setup();
1082 	r4k_blast_scache_setup();
1083 
1084 	/*
1085 	 * Some MIPS32 and MIPS64 processors have physically indexed caches.
1086 	 * This code supports virtually indexed processors and will be
1087 	 * unnecessarily inefficient on physically indexed processors.
1088 	 */
1089 	shm_align_mask = max_t( unsigned long,
1090 				c->dcache.sets * c->dcache.linesz - 1,
1091 				PAGE_SIZE - 1);
1092 
1093 	_flush_cache_all	= r4k_flush_cache_all;
1094 	___flush_cache_all	= r4k___flush_cache_all;
1095 	_flush_cache_mm		= r4k_flush_cache_mm;
1096 	_flush_cache_page	= r4k_flush_cache_page;
1097 	_flush_icache_page	= r4k_flush_icache_page;
1098 	_flush_cache_range	= r4k_flush_cache_range;
1099 
1100 	_flush_cache_sigtramp	= r4k_flush_cache_sigtramp;
1101 	_flush_icache_all	= r4k_flush_icache_all;
1102 	_flush_data_cache_page	= r4k_flush_data_cache_page;
1103 	_flush_icache_range	= r4k_flush_icache_range;
1104 
1105 #ifdef CONFIG_NONCOHERENT_IO
1106 	_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
1107 	_dma_cache_wback	= r4k_dma_cache_wback_inv;
1108 	_dma_cache_inv		= r4k_dma_cache_inv;
1109 #endif
1110 
1111 	__flush_cache_all();
1112 	coherency_setup();
1113 
1114 	build_clear_page();
1115 	build_copy_page();
1116 }
1117