xref: /linux/arch/mips/kernel/cpu-probe.c (revision c0c9209ddd96bc4f1d70a8b9958710671e076080)
1 /*
2  * Processor capabilities determination functions.
3  *
4  * Copyright (C) xxxx  the Anonymous
5  * Copyright (C) 1994 - 2006 Ralf Baechle
6  * Copyright (C) 2003, 2004  Maciej W. Rozycki
7  * Copyright (C) 2001, 2004  MIPS Inc.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/ptrace.h>
17 #include <linux/stddef.h>
18 
19 #include <asm/bugs.h>
20 #include <asm/cpu.h>
21 #include <asm/fpu.h>
22 #include <asm/mipsregs.h>
23 #include <asm/system.h>
24 
25 /*
26  * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
27  * the implementation of the "wait" feature differs between CPU families. This
28  * points to the function that implements CPU specific wait.
29  * The wait instruction stops the pipeline and reduces the power consumption of
30  * the CPU very much.
31  */
32 void (*cpu_wait)(void) = NULL;
33 
34 static void r3081_wait(void)
35 {
36 	unsigned long cfg = read_c0_conf();
37 	write_c0_conf(cfg | R30XX_CONF_HALT);
38 }
39 
40 static void r39xx_wait(void)
41 {
42 	local_irq_disable();
43 	if (!need_resched())
44 		write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
45 	local_irq_enable();
46 }
47 
48 extern void r4k_wait(void);
49 
50 /*
51  * This variant is preferable as it allows testing need_resched and going to
52  * sleep depending on the outcome atomically.  Unfortunately the "It is
53  * implementation-dependent whether the pipeline restarts when a non-enabled
54  * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
55  * using this version a gamble.
56  */
57 static void r4k_wait_irqoff(void)
58 {
59 	local_irq_disable();
60 	if (!need_resched())
61 		__asm__("	.set	mips3		\n"
62 			"	wait			\n"
63 			"	.set	mips0		\n");
64 	local_irq_enable();
65 }
66 
67 /*
68  * The RM7000 variant has to handle erratum 38.  The workaround is to not
69  * have any pending stores when the WAIT instruction is executed.
70  */
71 static void rm7k_wait_irqoff(void)
72 {
73 	local_irq_disable();
74 	if (!need_resched())
75 		__asm__(
76 		"	.set	push					\n"
77 		"	.set	mips3					\n"
78 		"	.set	noat					\n"
79 		"	mfc0	$1, $12					\n"
80 		"	sync						\n"
81 		"	mtc0	$1, $12		# stalls until W stage	\n"
82 		"	wait						\n"
83 		"	mtc0	$1, $12		# stalls until W stage	\n"
84 		"	.set	pop					\n");
85 	local_irq_enable();
86 }
87 
88 /* The Au1xxx wait is available only if using 32khz counter or
89  * external timer source, but specifically not CP0 Counter. */
90 int allow_au1k_wait;
91 
92 static void au1k_wait(void)
93 {
94 	/* using the wait instruction makes CP0 counter unusable */
95 	__asm__("	.set	mips3			\n"
96 		"	cache	0x14, 0(%0)		\n"
97 		"	cache	0x14, 32(%0)		\n"
98 		"	sync				\n"
99 		"	nop				\n"
100 		"	wait				\n"
101 		"	nop				\n"
102 		"	nop				\n"
103 		"	nop				\n"
104 		"	nop				\n"
105 		"	.set	mips0			\n"
106 		: : "r" (au1k_wait));
107 }
108 
109 static int __initdata nowait = 0;
110 
111 static int __init wait_disable(char *s)
112 {
113 	nowait = 1;
114 
115 	return 1;
116 }
117 
118 __setup("nowait", wait_disable);
119 
120 void __init check_wait(void)
121 {
122 	struct cpuinfo_mips *c = &current_cpu_data;
123 
124 	if (nowait) {
125 		printk("Wait instruction disabled.\n");
126 		return;
127 	}
128 
129 	switch (c->cputype) {
130 	case CPU_R3081:
131 	case CPU_R3081E:
132 		cpu_wait = r3081_wait;
133 		break;
134 	case CPU_TX3927:
135 		cpu_wait = r39xx_wait;
136 		break;
137 	case CPU_R4200:
138 /*	case CPU_R4300: */
139 	case CPU_R4600:
140 	case CPU_R4640:
141 	case CPU_R4650:
142 	case CPU_R4700:
143 	case CPU_R5000:
144 	case CPU_NEVADA:
145 	case CPU_4KC:
146 	case CPU_4KEC:
147 	case CPU_4KSC:
148 	case CPU_5KC:
149 	case CPU_25KF:
150 	case CPU_PR4450:
151 	case CPU_BCM3302:
152 		cpu_wait = r4k_wait;
153 		break;
154 
155 	case CPU_RM7000:
156 		cpu_wait = rm7k_wait_irqoff;
157 		break;
158 
159 	case CPU_24K:
160 	case CPU_34K:
161 	case CPU_1004K:
162 		cpu_wait = r4k_wait;
163 		if (read_c0_config7() & MIPS_CONF7_WII)
164 			cpu_wait = r4k_wait_irqoff;
165 		break;
166 
167 	case CPU_74K:
168 		cpu_wait = r4k_wait;
169 		if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
170 			cpu_wait = r4k_wait_irqoff;
171 		break;
172 
173 	case CPU_TX49XX:
174 		cpu_wait = r4k_wait_irqoff;
175 		break;
176 	case CPU_AU1000:
177 	case CPU_AU1100:
178 	case CPU_AU1500:
179 	case CPU_AU1550:
180 	case CPU_AU1200:
181 	case CPU_AU1210:
182 	case CPU_AU1250:
183 		if (allow_au1k_wait)
184 			cpu_wait = au1k_wait;
185 		break;
186 	case CPU_20KC:
187 		/*
188 		 * WAIT on Rev1.0 has E1, E2, E3 and E16.
189 		 * WAIT on Rev2.0 and Rev3.0 has E16.
190 		 * Rev3.1 WAIT is nop, why bother
191 		 */
192 		if ((c->processor_id & 0xff) <= 0x64)
193 			break;
194 
195 		/*
196 		 * Another rev is incremeting c0_count at a reduced clock
197 		 * rate while in WAIT mode.  So we basically have the choice
198 		 * between using the cp0 timer as clocksource or avoiding
199 		 * the WAIT instruction.  Until more details are known,
200 		 * disable the use of WAIT for 20Kc entirely.
201 		   cpu_wait = r4k_wait;
202 		 */
203 		break;
204 	case CPU_RM9000:
205 		if ((c->processor_id & 0x00ff) >= 0x40)
206 			cpu_wait = r4k_wait;
207 		break;
208 	default:
209 		break;
210 	}
211 }
212 
213 static inline void check_errata(void)
214 {
215 	struct cpuinfo_mips *c = &current_cpu_data;
216 
217 	switch (c->cputype) {
218 	case CPU_34K:
219 		/*
220 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
221 		 * This code only handles VPE0, any SMP/SMTC/RTOS code
222 		 * making use of VPE1 will be responsable for that VPE.
223 		 */
224 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
225 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
226 		break;
227 	default:
228 		break;
229 	}
230 }
231 
232 void __init check_bugs32(void)
233 {
234 	check_errata();
235 }
236 
237 /*
238  * Probe whether cpu has config register by trying to play with
239  * alternate cache bit and see whether it matters.
240  * It's used by cpu_probe to distinguish between R3000A and R3081.
241  */
242 static inline int cpu_has_confreg(void)
243 {
244 #ifdef CONFIG_CPU_R3000
245 	extern unsigned long r3k_cache_size(unsigned long);
246 	unsigned long size1, size2;
247 	unsigned long cfg = read_c0_conf();
248 
249 	size1 = r3k_cache_size(ST0_ISC);
250 	write_c0_conf(cfg ^ R30XX_CONF_AC);
251 	size2 = r3k_cache_size(ST0_ISC);
252 	write_c0_conf(cfg);
253 	return size1 != size2;
254 #else
255 	return 0;
256 #endif
257 }
258 
259 /*
260  * Get the FPU Implementation/Revision.
261  */
262 static inline unsigned long cpu_get_fpu_id(void)
263 {
264 	unsigned long tmp, fpu_id;
265 
266 	tmp = read_c0_status();
267 	__enable_fpu();
268 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
269 	write_c0_status(tmp);
270 	return fpu_id;
271 }
272 
273 /*
274  * Check the CPU has an FPU the official way.
275  */
276 static inline int __cpu_has_fpu(void)
277 {
278 	return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
279 }
280 
281 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
282 		| MIPS_CPU_COUNTER)
283 
284 static inline void cpu_probe_legacy(struct cpuinfo_mips *c)
285 {
286 	switch (c->processor_id & 0xff00) {
287 	case PRID_IMP_R2000:
288 		c->cputype = CPU_R2000;
289 		c->isa_level = MIPS_CPU_ISA_I;
290 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
291 		             MIPS_CPU_NOFPUEX;
292 		if (__cpu_has_fpu())
293 			c->options |= MIPS_CPU_FPU;
294 		c->tlbsize = 64;
295 		break;
296 	case PRID_IMP_R3000:
297 		if ((c->processor_id & 0xff) == PRID_REV_R3000A)
298 			if (cpu_has_confreg())
299 				c->cputype = CPU_R3081E;
300 			else
301 				c->cputype = CPU_R3000A;
302 		else
303 			c->cputype = CPU_R3000;
304 		c->isa_level = MIPS_CPU_ISA_I;
305 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
306 		             MIPS_CPU_NOFPUEX;
307 		if (__cpu_has_fpu())
308 			c->options |= MIPS_CPU_FPU;
309 		c->tlbsize = 64;
310 		break;
311 	case PRID_IMP_R4000:
312 		if (read_c0_config() & CONF_SC) {
313 			if ((c->processor_id & 0xff) >= PRID_REV_R4400)
314 				c->cputype = CPU_R4400PC;
315 			else
316 				c->cputype = CPU_R4000PC;
317 		} else {
318 			if ((c->processor_id & 0xff) >= PRID_REV_R4400)
319 				c->cputype = CPU_R4400SC;
320 			else
321 				c->cputype = CPU_R4000SC;
322 		}
323 
324 		c->isa_level = MIPS_CPU_ISA_III;
325 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
326 		             MIPS_CPU_WATCH | MIPS_CPU_VCE |
327 		             MIPS_CPU_LLSC;
328 		c->tlbsize = 48;
329 		break;
330 	case PRID_IMP_VR41XX:
331 		switch (c->processor_id & 0xf0) {
332 		case PRID_REV_VR4111:
333 			c->cputype = CPU_VR4111;
334 			break;
335 		case PRID_REV_VR4121:
336 			c->cputype = CPU_VR4121;
337 			break;
338 		case PRID_REV_VR4122:
339 			if ((c->processor_id & 0xf) < 0x3)
340 				c->cputype = CPU_VR4122;
341 			else
342 				c->cputype = CPU_VR4181A;
343 			break;
344 		case PRID_REV_VR4130:
345 			if ((c->processor_id & 0xf) < 0x4)
346 				c->cputype = CPU_VR4131;
347 			else
348 				c->cputype = CPU_VR4133;
349 			break;
350 		default:
351 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
352 			c->cputype = CPU_VR41XX;
353 			break;
354 		}
355 		c->isa_level = MIPS_CPU_ISA_III;
356 		c->options = R4K_OPTS;
357 		c->tlbsize = 32;
358 		break;
359 	case PRID_IMP_R4300:
360 		c->cputype = CPU_R4300;
361 		c->isa_level = MIPS_CPU_ISA_III;
362 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
363 		             MIPS_CPU_LLSC;
364 		c->tlbsize = 32;
365 		break;
366 	case PRID_IMP_R4600:
367 		c->cputype = CPU_R4600;
368 		c->isa_level = MIPS_CPU_ISA_III;
369 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
370 			     MIPS_CPU_LLSC;
371 		c->tlbsize = 48;
372 		break;
373 	#if 0
374  	case PRID_IMP_R4650:
375 		/*
376 		 * This processor doesn't have an MMU, so it's not
377 		 * "real easy" to run Linux on it. It is left purely
378 		 * for documentation.  Commented out because it shares
379 		 * it's c0_prid id number with the TX3900.
380 		 */
381 		c->cputype = CPU_R4650;
382 	 	c->isa_level = MIPS_CPU_ISA_III;
383 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
384 	        c->tlbsize = 48;
385 		break;
386 	#endif
387 	case PRID_IMP_TX39:
388 		c->isa_level = MIPS_CPU_ISA_I;
389 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
390 
391 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
392 			c->cputype = CPU_TX3927;
393 			c->tlbsize = 64;
394 		} else {
395 			switch (c->processor_id & 0xff) {
396 			case PRID_REV_TX3912:
397 				c->cputype = CPU_TX3912;
398 				c->tlbsize = 32;
399 				break;
400 			case PRID_REV_TX3922:
401 				c->cputype = CPU_TX3922;
402 				c->tlbsize = 64;
403 				break;
404 			default:
405 				c->cputype = CPU_UNKNOWN;
406 				break;
407 			}
408 		}
409 		break;
410 	case PRID_IMP_R4700:
411 		c->cputype = CPU_R4700;
412 		c->isa_level = MIPS_CPU_ISA_III;
413 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
414 		             MIPS_CPU_LLSC;
415 		c->tlbsize = 48;
416 		break;
417 	case PRID_IMP_TX49:
418 		c->cputype = CPU_TX49XX;
419 		c->isa_level = MIPS_CPU_ISA_III;
420 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
421 		if (!(c->processor_id & 0x08))
422 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
423 		c->tlbsize = 48;
424 		break;
425 	case PRID_IMP_R5000:
426 		c->cputype = CPU_R5000;
427 		c->isa_level = MIPS_CPU_ISA_IV;
428 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
429 		             MIPS_CPU_LLSC;
430 		c->tlbsize = 48;
431 		break;
432 	case PRID_IMP_R5432:
433 		c->cputype = CPU_R5432;
434 		c->isa_level = MIPS_CPU_ISA_IV;
435 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
436 		             MIPS_CPU_WATCH | MIPS_CPU_LLSC;
437 		c->tlbsize = 48;
438 		break;
439 	case PRID_IMP_R5500:
440 		c->cputype = CPU_R5500;
441 		c->isa_level = MIPS_CPU_ISA_IV;
442 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
443 		             MIPS_CPU_WATCH | MIPS_CPU_LLSC;
444 		c->tlbsize = 48;
445 		break;
446 	case PRID_IMP_NEVADA:
447 		c->cputype = CPU_NEVADA;
448 		c->isa_level = MIPS_CPU_ISA_IV;
449 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
450 		             MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
451 		c->tlbsize = 48;
452 		break;
453 	case PRID_IMP_R6000:
454 		c->cputype = CPU_R6000;
455 		c->isa_level = MIPS_CPU_ISA_II;
456 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
457 		             MIPS_CPU_LLSC;
458 		c->tlbsize = 32;
459 		break;
460 	case PRID_IMP_R6000A:
461 		c->cputype = CPU_R6000A;
462 		c->isa_level = MIPS_CPU_ISA_II;
463 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
464 		             MIPS_CPU_LLSC;
465 		c->tlbsize = 32;
466 		break;
467 	case PRID_IMP_RM7000:
468 		c->cputype = CPU_RM7000;
469 		c->isa_level = MIPS_CPU_ISA_IV;
470 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
471 		             MIPS_CPU_LLSC;
472 		/*
473 		 * Undocumented RM7000:  Bit 29 in the info register of
474 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
475 		 * entries.
476 		 *
477 		 * 29      1 =>    64 entry JTLB
478 		 *         0 =>    48 entry JTLB
479 		 */
480 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
481 		break;
482 	case PRID_IMP_RM9000:
483 		c->cputype = CPU_RM9000;
484 		c->isa_level = MIPS_CPU_ISA_IV;
485 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
486 		             MIPS_CPU_LLSC;
487 		/*
488 		 * Bit 29 in the info register of the RM9000
489 		 * indicates if the TLB has 48 or 64 entries.
490 		 *
491 		 * 29      1 =>    64 entry JTLB
492 		 *         0 =>    48 entry JTLB
493 		 */
494 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
495 		break;
496 	case PRID_IMP_R8000:
497 		c->cputype = CPU_R8000;
498 		c->isa_level = MIPS_CPU_ISA_IV;
499 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
500 		             MIPS_CPU_FPU | MIPS_CPU_32FPR |
501 		             MIPS_CPU_LLSC;
502 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
503 		break;
504 	case PRID_IMP_R10000:
505 		c->cputype = CPU_R10000;
506 		c->isa_level = MIPS_CPU_ISA_IV;
507 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
508 		             MIPS_CPU_FPU | MIPS_CPU_32FPR |
509 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
510 		             MIPS_CPU_LLSC;
511 		c->tlbsize = 64;
512 		break;
513 	case PRID_IMP_R12000:
514 		c->cputype = CPU_R12000;
515 		c->isa_level = MIPS_CPU_ISA_IV;
516 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
517 		             MIPS_CPU_FPU | MIPS_CPU_32FPR |
518 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
519 		             MIPS_CPU_LLSC;
520 		c->tlbsize = 64;
521 		break;
522 	case PRID_IMP_R14000:
523 		c->cputype = CPU_R14000;
524 		c->isa_level = MIPS_CPU_ISA_IV;
525 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
526 		             MIPS_CPU_FPU | MIPS_CPU_32FPR |
527 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
528 		             MIPS_CPU_LLSC;
529 		c->tlbsize = 64;
530 		break;
531 	case PRID_IMP_LOONGSON2:
532 		c->cputype = CPU_LOONGSON2;
533 		c->isa_level = MIPS_CPU_ISA_III;
534 		c->options = R4K_OPTS |
535 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
536 			     MIPS_CPU_32FPR;
537 		c->tlbsize = 64;
538 		break;
539 	}
540 }
541 
542 static char unknown_isa[] __cpuinitdata = KERN_ERR \
543 	"Unsupported ISA type, c0.config0: %d.";
544 
545 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
546 {
547 	unsigned int config0;
548 	int isa;
549 
550 	config0 = read_c0_config();
551 
552 	if (((config0 & MIPS_CONF_MT) >> 7) == 1)
553 		c->options |= MIPS_CPU_TLB;
554 	isa = (config0 & MIPS_CONF_AT) >> 13;
555 	switch (isa) {
556 	case 0:
557 		switch ((config0 & MIPS_CONF_AR) >> 10) {
558 		case 0:
559 			c->isa_level = MIPS_CPU_ISA_M32R1;
560 			break;
561 		case 1:
562 			c->isa_level = MIPS_CPU_ISA_M32R2;
563 			break;
564 		default:
565 			goto unknown;
566 		}
567 		break;
568 	case 2:
569 		switch ((config0 & MIPS_CONF_AR) >> 10) {
570 		case 0:
571 			c->isa_level = MIPS_CPU_ISA_M64R1;
572 			break;
573 		case 1:
574 			c->isa_level = MIPS_CPU_ISA_M64R2;
575 			break;
576 		default:
577 			goto unknown;
578 		}
579 		break;
580 	default:
581 		goto unknown;
582 	}
583 
584 	return config0 & MIPS_CONF_M;
585 
586 unknown:
587 	panic(unknown_isa, config0);
588 }
589 
590 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
591 {
592 	unsigned int config1;
593 
594 	config1 = read_c0_config1();
595 
596 	if (config1 & MIPS_CONF1_MD)
597 		c->ases |= MIPS_ASE_MDMX;
598 	if (config1 & MIPS_CONF1_WR)
599 		c->options |= MIPS_CPU_WATCH;
600 	if (config1 & MIPS_CONF1_CA)
601 		c->ases |= MIPS_ASE_MIPS16;
602 	if (config1 & MIPS_CONF1_EP)
603 		c->options |= MIPS_CPU_EJTAG;
604 	if (config1 & MIPS_CONF1_FP) {
605 		c->options |= MIPS_CPU_FPU;
606 		c->options |= MIPS_CPU_32FPR;
607 	}
608 	if (cpu_has_tlb)
609 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
610 
611 	return config1 & MIPS_CONF_M;
612 }
613 
614 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
615 {
616 	unsigned int config2;
617 
618 	config2 = read_c0_config2();
619 
620 	if (config2 & MIPS_CONF2_SL)
621 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
622 
623 	return config2 & MIPS_CONF_M;
624 }
625 
626 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
627 {
628 	unsigned int config3;
629 
630 	config3 = read_c0_config3();
631 
632 	if (config3 & MIPS_CONF3_SM)
633 		c->ases |= MIPS_ASE_SMARTMIPS;
634 	if (config3 & MIPS_CONF3_DSP)
635 		c->ases |= MIPS_ASE_DSP;
636 	if (config3 & MIPS_CONF3_VINT)
637 		c->options |= MIPS_CPU_VINT;
638 	if (config3 & MIPS_CONF3_VEIC)
639 		c->options |= MIPS_CPU_VEIC;
640 	if (config3 & MIPS_CONF3_MT)
641 	        c->ases |= MIPS_ASE_MIPSMT;
642 	if (config3 & MIPS_CONF3_ULRI)
643 		c->options |= MIPS_CPU_ULRI;
644 
645 	return config3 & MIPS_CONF_M;
646 }
647 
648 static void __cpuinit decode_configs(struct cpuinfo_mips *c)
649 {
650 	/* MIPS32 or MIPS64 compliant CPU.  */
651 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
652 	             MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
653 
654 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
655 
656 	/* Read Config registers.  */
657 	if (!decode_config0(c))
658 		return;			/* actually worth a panic() */
659 	if (!decode_config1(c))
660 		return;
661 	if (!decode_config2(c))
662 		return;
663 	if (!decode_config3(c))
664 		return;
665 }
666 
667 #ifdef CONFIG_CPU_MIPSR2
668 extern void spram_config(void);
669 #else
670 static inline void spram_config(void) {}
671 #endif
672 
673 static inline void cpu_probe_mips(struct cpuinfo_mips *c)
674 {
675 	decode_configs(c);
676 	switch (c->processor_id & 0xff00) {
677 	case PRID_IMP_4KC:
678 		c->cputype = CPU_4KC;
679 		break;
680 	case PRID_IMP_4KEC:
681 		c->cputype = CPU_4KEC;
682 		break;
683 	case PRID_IMP_4KECR2:
684 		c->cputype = CPU_4KEC;
685 		break;
686 	case PRID_IMP_4KSC:
687 	case PRID_IMP_4KSD:
688 		c->cputype = CPU_4KSC;
689 		break;
690 	case PRID_IMP_5KC:
691 		c->cputype = CPU_5KC;
692 		break;
693 	case PRID_IMP_20KC:
694 		c->cputype = CPU_20KC;
695 		break;
696 	case PRID_IMP_24K:
697 	case PRID_IMP_24KE:
698 		c->cputype = CPU_24K;
699 		break;
700 	case PRID_IMP_25KF:
701 		c->cputype = CPU_25KF;
702 		break;
703 	case PRID_IMP_34K:
704 		c->cputype = CPU_34K;
705 		break;
706 	case PRID_IMP_74K:
707 		c->cputype = CPU_74K;
708 		break;
709 	case PRID_IMP_1004K:
710 		c->cputype = CPU_1004K;
711 		break;
712 	}
713 
714 	spram_config();
715 }
716 
717 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c)
718 {
719 	decode_configs(c);
720 	switch (c->processor_id & 0xff00) {
721 	case PRID_IMP_AU1_REV1:
722 	case PRID_IMP_AU1_REV2:
723 		switch ((c->processor_id >> 24) & 0xff) {
724 		case 0:
725 			c->cputype = CPU_AU1000;
726 			break;
727 		case 1:
728 			c->cputype = CPU_AU1500;
729 			break;
730 		case 2:
731 			c->cputype = CPU_AU1100;
732 			break;
733 		case 3:
734 			c->cputype = CPU_AU1550;
735 			break;
736 		case 4:
737 			c->cputype = CPU_AU1200;
738 			if (2 == (c->processor_id & 0xff))
739 				c->cputype = CPU_AU1250;
740 			break;
741 		case 5:
742 			c->cputype = CPU_AU1210;
743 			break;
744 		default:
745 			panic("Unknown Au Core!");
746 			break;
747 		}
748 		break;
749 	}
750 }
751 
752 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c)
753 {
754 	decode_configs(c);
755 
756 	switch (c->processor_id & 0xff00) {
757 	case PRID_IMP_SB1:
758 		c->cputype = CPU_SB1;
759 		/* FPU in pass1 is known to have issues. */
760 		if ((c->processor_id & 0xff) < 0x02)
761 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
762 		break;
763 	case PRID_IMP_SB1A:
764 		c->cputype = CPU_SB1A;
765 		break;
766 	}
767 }
768 
769 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c)
770 {
771 	decode_configs(c);
772 	switch (c->processor_id & 0xff00) {
773 	case PRID_IMP_SR71000:
774 		c->cputype = CPU_SR71000;
775 		c->scache.ways = 8;
776 		c->tlbsize = 64;
777 		break;
778 	}
779 }
780 
781 static inline void cpu_probe_nxp(struct cpuinfo_mips *c)
782 {
783 	decode_configs(c);
784 	switch (c->processor_id & 0xff00) {
785 	case PRID_IMP_PR4450:
786 		c->cputype = CPU_PR4450;
787 		c->isa_level = MIPS_CPU_ISA_M32R1;
788 		break;
789 	default:
790 		panic("Unknown NXP Core!"); /* REVISIT: die? */
791 		break;
792 	}
793 }
794 
795 
796 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c)
797 {
798 	decode_configs(c);
799 	switch (c->processor_id & 0xff00) {
800 	case PRID_IMP_BCM3302:
801 		c->cputype = CPU_BCM3302;
802 		break;
803 	case PRID_IMP_BCM4710:
804 		c->cputype = CPU_BCM4710;
805 		break;
806 	default:
807 		c->cputype = CPU_UNKNOWN;
808 		break;
809 	}
810 }
811 
812 const char *__cpu_name[NR_CPUS];
813 
814 /*
815  * Name a CPU
816  */
817 static __cpuinit const char *cpu_to_name(struct cpuinfo_mips *c)
818 {
819 	const char *name = NULL;
820 
821 	switch (c->cputype) {
822 	case CPU_UNKNOWN:	name = "unknown"; break;
823 	case CPU_R2000:		name = "R2000"; break;
824 	case CPU_R3000:		name = "R3000"; break;
825 	case CPU_R3000A:	name = "R3000A"; break;
826 	case CPU_R3041:		name = "R3041"; break;
827 	case CPU_R3051:		name = "R3051"; break;
828 	case CPU_R3052:		name = "R3052"; break;
829 	case CPU_R3081:		name = "R3081"; break;
830 	case CPU_R3081E:	name = "R3081E"; break;
831 	case CPU_R4000PC:	name = "R4000PC"; break;
832 	case CPU_R4000SC:	name = "R4000SC"; break;
833 	case CPU_R4000MC:	name = "R4000MC"; break;
834 	case CPU_R4200:		name = "R4200"; break;
835 	case CPU_R4400PC:	name = "R4400PC"; break;
836 	case CPU_R4400SC:	name = "R4400SC"; break;
837 	case CPU_R4400MC:	name = "R4400MC"; break;
838 	case CPU_R4600:		name = "R4600"; break;
839 	case CPU_R6000:		name = "R6000"; break;
840 	case CPU_R6000A:	name = "R6000A"; break;
841 	case CPU_R8000:		name = "R8000"; break;
842 	case CPU_R10000:	name = "R10000"; break;
843 	case CPU_R12000:	name = "R12000"; break;
844 	case CPU_R14000:	name = "R14000"; break;
845 	case CPU_R4300:		name = "R4300"; break;
846 	case CPU_R4650:		name = "R4650"; break;
847 	case CPU_R4700:		name = "R4700"; break;
848 	case CPU_R5000:		name = "R5000"; break;
849 	case CPU_R5000A:	name = "R5000A"; break;
850 	case CPU_R4640:		name = "R4640"; break;
851 	case CPU_NEVADA:	name = "Nevada"; break;
852 	case CPU_RM7000:	name = "RM7000"; break;
853 	case CPU_RM9000:	name = "RM9000"; break;
854 	case CPU_R5432:		name = "R5432"; break;
855 	case CPU_4KC:		name = "MIPS 4Kc"; break;
856 	case CPU_5KC:		name = "MIPS 5Kc"; break;
857 	case CPU_R4310:		name = "R4310"; break;
858 	case CPU_SB1:		name = "SiByte SB1"; break;
859 	case CPU_SB1A:		name = "SiByte SB1A"; break;
860 	case CPU_TX3912:	name = "TX3912"; break;
861 	case CPU_TX3922:	name = "TX3922"; break;
862 	case CPU_TX3927:	name = "TX3927"; break;
863 	case CPU_AU1000:	name = "Au1000"; break;
864 	case CPU_AU1500:	name = "Au1500"; break;
865 	case CPU_AU1100:	name = "Au1100"; break;
866 	case CPU_AU1550:	name = "Au1550"; break;
867 	case CPU_AU1200:	name = "Au1200"; break;
868 	case CPU_AU1210:	name = "Au1210"; break;
869 	case CPU_AU1250:	name = "Au1250"; break;
870 	case CPU_4KEC:		name = "MIPS 4KEc"; break;
871 	case CPU_4KSC:		name = "MIPS 4KSc"; break;
872 	case CPU_VR41XX:	name = "NEC Vr41xx"; break;
873 	case CPU_R5500:		name = "R5500"; break;
874 	case CPU_TX49XX:	name = "TX49xx"; break;
875 	case CPU_20KC:		name = "MIPS 20Kc"; break;
876 	case CPU_24K:		name = "MIPS 24K"; break;
877 	case CPU_25KF:		name = "MIPS 25Kf"; break;
878 	case CPU_34K:		name = "MIPS 34K"; break;
879 	case CPU_1004K:		name = "MIPS 1004K"; break;
880 	case CPU_74K:		name = "MIPS 74K"; break;
881 	case CPU_VR4111:	name = "NEC VR4111"; break;
882 	case CPU_VR4121:	name = "NEC VR4121"; break;
883 	case CPU_VR4122:	name = "NEC VR4122"; break;
884 	case CPU_VR4131:	name = "NEC VR4131"; break;
885 	case CPU_VR4133:	name = "NEC VR4133"; break;
886 	case CPU_VR4181:	name = "NEC VR4181"; break;
887 	case CPU_VR4181A:	name = "NEC VR4181A"; break;
888 	case CPU_SR71000:	name = "Sandcraft SR71000"; break;
889 	case CPU_BCM3302:	name = "Broadcom BCM3302"; break;
890 	case CPU_BCM4710:	name = "Broadcom BCM4710"; break;
891 	case CPU_PR4450:	name = "Philips PR4450"; break;
892 	case CPU_LOONGSON2:	name = "ICT Loongson-2"; break;
893 	default:
894 		BUG();
895 	}
896 
897 	return name;
898 }
899 
900 __cpuinit void cpu_probe(void)
901 {
902 	struct cpuinfo_mips *c = &current_cpu_data;
903 	unsigned int cpu = smp_processor_id();
904 
905 	c->processor_id	= PRID_IMP_UNKNOWN;
906 	c->fpu_id	= FPIR_IMP_NONE;
907 	c->cputype	= CPU_UNKNOWN;
908 
909 	c->processor_id = read_c0_prid();
910 	switch (c->processor_id & 0xff0000) {
911 	case PRID_COMP_LEGACY:
912 		cpu_probe_legacy(c);
913 		break;
914 	case PRID_COMP_MIPS:
915 		cpu_probe_mips(c);
916 		break;
917 	case PRID_COMP_ALCHEMY:
918 		cpu_probe_alchemy(c);
919 		break;
920 	case PRID_COMP_SIBYTE:
921 		cpu_probe_sibyte(c);
922 		break;
923 	case PRID_COMP_BROADCOM:
924 		cpu_probe_broadcom(c);
925 		break;
926 	case PRID_COMP_SANDCRAFT:
927 		cpu_probe_sandcraft(c);
928 		break;
929 	case PRID_COMP_NXP:
930 		cpu_probe_nxp(c);
931 		break;
932 	default:
933 		c->cputype = CPU_UNKNOWN;
934 	}
935 
936 	/*
937 	 * Platform code can force the cpu type to optimize code
938 	 * generation. In that case be sure the cpu type is correctly
939 	 * manually setup otherwise it could trigger some nasty bugs.
940 	 */
941 	BUG_ON(current_cpu_type() != c->cputype);
942 
943 	if (c->options & MIPS_CPU_FPU) {
944 		c->fpu_id = cpu_get_fpu_id();
945 
946 		if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
947 		    c->isa_level == MIPS_CPU_ISA_M32R2 ||
948 		    c->isa_level == MIPS_CPU_ISA_M64R1 ||
949 		    c->isa_level == MIPS_CPU_ISA_M64R2) {
950 			if (c->fpu_id & MIPS_FPIR_3D)
951 				c->ases |= MIPS_ASE_MIPS3D;
952 		}
953 	}
954 
955 	__cpu_name[cpu] = cpu_to_name(c);
956 
957 	if (cpu_has_mips_r2)
958 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
959 	else
960 		c->srsets = 1;
961 }
962 
963 __cpuinit void cpu_report(void)
964 {
965 	struct cpuinfo_mips *c = &current_cpu_data;
966 
967 	printk(KERN_INFO "CPU revision is: %08x (%s)\n",
968 	       c->processor_id, cpu_name_string());
969 	if (c->options & MIPS_CPU_FPU)
970 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
971 }
972