xref: /linux/arch/mips/kernel/cpu-probe.c (revision 4a8e43feeac7996b8de2d5b2823e316917493df4)
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, 2011, 2012  MIPS Technologies, 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/smp.h>
18 #include <linux/stddef.h>
19 #include <linux/export.h>
20 
21 #include <asm/bugs.h>
22 #include <asm/cpu.h>
23 #include <asm/fpu.h>
24 #include <asm/mipsregs.h>
25 #include <asm/watch.h>
26 #include <asm/elf.h>
27 #include <asm/spram.h>
28 #include <asm/uaccess.h>
29 
30 /*
31  * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
32  * the implementation of the "wait" feature differs between CPU families. This
33  * points to the function that implements CPU specific wait.
34  * The wait instruction stops the pipeline and reduces the power consumption of
35  * the CPU very much.
36  */
37 void (*cpu_wait)(void);
38 EXPORT_SYMBOL(cpu_wait);
39 
40 static void r3081_wait(void)
41 {
42 	unsigned long cfg = read_c0_conf();
43 	write_c0_conf(cfg | R30XX_CONF_HALT);
44 }
45 
46 static void r39xx_wait(void)
47 {
48 	local_irq_disable();
49 	if (!need_resched())
50 		write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
51 	local_irq_enable();
52 }
53 
54 extern void r4k_wait(void);
55 
56 /*
57  * This variant is preferable as it allows testing need_resched and going to
58  * sleep depending on the outcome atomically.  Unfortunately the "It is
59  * implementation-dependent whether the pipeline restarts when a non-enabled
60  * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
61  * using this version a gamble.
62  */
63 void r4k_wait_irqoff(void)
64 {
65 	local_irq_disable();
66 	if (!need_resched())
67 		__asm__("	.set	push		\n"
68 			"	.set	mips3		\n"
69 			"	wait			\n"
70 			"	.set	pop		\n");
71 	local_irq_enable();
72 	__asm__(" 	.globl __pastwait	\n"
73 		"__pastwait:			\n");
74 }
75 
76 /*
77  * The RM7000 variant has to handle erratum 38.  The workaround is to not
78  * have any pending stores when the WAIT instruction is executed.
79  */
80 static void rm7k_wait_irqoff(void)
81 {
82 	local_irq_disable();
83 	if (!need_resched())
84 		__asm__(
85 		"	.set	push					\n"
86 		"	.set	mips3					\n"
87 		"	.set	noat					\n"
88 		"	mfc0	$1, $12					\n"
89 		"	sync						\n"
90 		"	mtc0	$1, $12		# stalls until W stage	\n"
91 		"	wait						\n"
92 		"	mtc0	$1, $12		# stalls until W stage	\n"
93 		"	.set	pop					\n");
94 	local_irq_enable();
95 }
96 
97 /*
98  * The Au1xxx wait is available only if using 32khz counter or
99  * external timer source, but specifically not CP0 Counter.
100  * alchemy/common/time.c may override cpu_wait!
101  */
102 static void au1k_wait(void)
103 {
104 	__asm__("	.set	mips3			\n"
105 		"	cache	0x14, 0(%0)		\n"
106 		"	cache	0x14, 32(%0)		\n"
107 		"	sync				\n"
108 		"	nop				\n"
109 		"	wait				\n"
110 		"	nop				\n"
111 		"	nop				\n"
112 		"	nop				\n"
113 		"	nop				\n"
114 		"	.set	mips0			\n"
115 		: : "r" (au1k_wait));
116 }
117 
118 static int __initdata nowait;
119 
120 static int __init wait_disable(char *s)
121 {
122 	nowait = 1;
123 
124 	return 1;
125 }
126 
127 __setup("nowait", wait_disable);
128 
129 static int __cpuinitdata mips_fpu_disabled;
130 
131 static int __init fpu_disable(char *s)
132 {
133 	cpu_data[0].options &= ~MIPS_CPU_FPU;
134 	mips_fpu_disabled = 1;
135 
136 	return 1;
137 }
138 
139 __setup("nofpu", fpu_disable);
140 
141 int __cpuinitdata mips_dsp_disabled;
142 
143 static int __init dsp_disable(char *s)
144 {
145 	cpu_data[0].ases &= ~MIPS_ASE_DSP;
146 	mips_dsp_disabled = 1;
147 
148 	return 1;
149 }
150 
151 __setup("nodsp", dsp_disable);
152 
153 void __init check_wait(void)
154 {
155 	struct cpuinfo_mips *c = &current_cpu_data;
156 
157 	if (nowait) {
158 		printk("Wait instruction disabled.\n");
159 		return;
160 	}
161 
162 	switch (c->cputype) {
163 	case CPU_R3081:
164 	case CPU_R3081E:
165 		cpu_wait = r3081_wait;
166 		break;
167 	case CPU_TX3927:
168 		cpu_wait = r39xx_wait;
169 		break;
170 	case CPU_R4200:
171 /*	case CPU_R4300: */
172 	case CPU_R4600:
173 	case CPU_R4640:
174 	case CPU_R4650:
175 	case CPU_R4700:
176 	case CPU_R5000:
177 	case CPU_R5500:
178 	case CPU_NEVADA:
179 	case CPU_4KC:
180 	case CPU_4KEC:
181 	case CPU_4KSC:
182 	case CPU_5KC:
183 	case CPU_25KF:
184 	case CPU_PR4450:
185 	case CPU_BMIPS3300:
186 	case CPU_BMIPS4350:
187 	case CPU_BMIPS4380:
188 	case CPU_BMIPS5000:
189 	case CPU_CAVIUM_OCTEON:
190 	case CPU_CAVIUM_OCTEON_PLUS:
191 	case CPU_CAVIUM_OCTEON2:
192 	case CPU_JZRISC:
193 	case CPU_LOONGSON1:
194 	case CPU_XLR:
195 	case CPU_XLP:
196 		cpu_wait = r4k_wait;
197 		break;
198 
199 	case CPU_RM7000:
200 		cpu_wait = rm7k_wait_irqoff;
201 		break;
202 
203 	case CPU_M14KC:
204 	case CPU_24K:
205 	case CPU_34K:
206 	case CPU_1004K:
207 		cpu_wait = r4k_wait;
208 		if (read_c0_config7() & MIPS_CONF7_WII)
209 			cpu_wait = r4k_wait_irqoff;
210 		break;
211 
212 	case CPU_74K:
213 		cpu_wait = r4k_wait;
214 		if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
215 			cpu_wait = r4k_wait_irqoff;
216 		break;
217 
218 	case CPU_TX49XX:
219 		cpu_wait = r4k_wait_irqoff;
220 		break;
221 	case CPU_ALCHEMY:
222 		cpu_wait = au1k_wait;
223 		break;
224 	case CPU_20KC:
225 		/*
226 		 * WAIT on Rev1.0 has E1, E2, E3 and E16.
227 		 * WAIT on Rev2.0 and Rev3.0 has E16.
228 		 * Rev3.1 WAIT is nop, why bother
229 		 */
230 		if ((c->processor_id & 0xff) <= 0x64)
231 			break;
232 
233 		/*
234 		 * Another rev is incremeting c0_count at a reduced clock
235 		 * rate while in WAIT mode.  So we basically have the choice
236 		 * between using the cp0 timer as clocksource or avoiding
237 		 * the WAIT instruction.  Until more details are known,
238 		 * disable the use of WAIT for 20Kc entirely.
239 		   cpu_wait = r4k_wait;
240 		 */
241 		break;
242 	case CPU_RM9000:
243 		if ((c->processor_id & 0x00ff) >= 0x40)
244 			cpu_wait = r4k_wait;
245 		break;
246 	default:
247 		break;
248 	}
249 }
250 
251 static inline void check_errata(void)
252 {
253 	struct cpuinfo_mips *c = &current_cpu_data;
254 
255 	switch (c->cputype) {
256 	case CPU_34K:
257 		/*
258 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
259 		 * This code only handles VPE0, any SMP/SMTC/RTOS code
260 		 * making use of VPE1 will be responsable for that VPE.
261 		 */
262 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
263 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
264 		break;
265 	default:
266 		break;
267 	}
268 }
269 
270 void __init check_bugs32(void)
271 {
272 	check_errata();
273 }
274 
275 /*
276  * Probe whether cpu has config register by trying to play with
277  * alternate cache bit and see whether it matters.
278  * It's used by cpu_probe to distinguish between R3000A and R3081.
279  */
280 static inline int cpu_has_confreg(void)
281 {
282 #ifdef CONFIG_CPU_R3000
283 	extern unsigned long r3k_cache_size(unsigned long);
284 	unsigned long size1, size2;
285 	unsigned long cfg = read_c0_conf();
286 
287 	size1 = r3k_cache_size(ST0_ISC);
288 	write_c0_conf(cfg ^ R30XX_CONF_AC);
289 	size2 = r3k_cache_size(ST0_ISC);
290 	write_c0_conf(cfg);
291 	return size1 != size2;
292 #else
293 	return 0;
294 #endif
295 }
296 
297 static inline void set_elf_platform(int cpu, const char *plat)
298 {
299 	if (cpu == 0)
300 		__elf_platform = plat;
301 }
302 
303 /*
304  * Get the FPU Implementation/Revision.
305  */
306 static inline unsigned long cpu_get_fpu_id(void)
307 {
308 	unsigned long tmp, fpu_id;
309 
310 	tmp = read_c0_status();
311 	__enable_fpu();
312 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
313 	write_c0_status(tmp);
314 	return fpu_id;
315 }
316 
317 /*
318  * Check the CPU has an FPU the official way.
319  */
320 static inline int __cpu_has_fpu(void)
321 {
322 	return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
323 }
324 
325 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
326 {
327 #ifdef __NEED_VMBITS_PROBE
328 	write_c0_entryhi(0x3fffffffffffe000ULL);
329 	back_to_back_c0_hazard();
330 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
331 #endif
332 }
333 
334 static char unknown_isa[] __cpuinitdata = KERN_ERR \
335 	"Unsupported ISA type, c0.config0: %d.";
336 
337 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
338 {
339 	unsigned int config0;
340 	int isa;
341 
342 	config0 = read_c0_config();
343 
344 	if (((config0 & MIPS_CONF_MT) >> 7) == 1)
345 		c->options |= MIPS_CPU_TLB;
346 	isa = (config0 & MIPS_CONF_AT) >> 13;
347 	switch (isa) {
348 	case 0:
349 		switch ((config0 & MIPS_CONF_AR) >> 10) {
350 		case 0:
351 			c->isa_level = MIPS_CPU_ISA_M32R1;
352 			break;
353 		case 1:
354 			c->isa_level = MIPS_CPU_ISA_M32R2;
355 			break;
356 		default:
357 			goto unknown;
358 		}
359 		break;
360 	case 2:
361 		switch ((config0 & MIPS_CONF_AR) >> 10) {
362 		case 0:
363 			c->isa_level = MIPS_CPU_ISA_M64R1;
364 			break;
365 		case 1:
366 			c->isa_level = MIPS_CPU_ISA_M64R2;
367 			break;
368 		default:
369 			goto unknown;
370 		}
371 		break;
372 	default:
373 		goto unknown;
374 	}
375 
376 	return config0 & MIPS_CONF_M;
377 
378 unknown:
379 	panic(unknown_isa, config0);
380 }
381 
382 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
383 {
384 	unsigned int config1;
385 
386 	config1 = read_c0_config1();
387 
388 	if (config1 & MIPS_CONF1_MD)
389 		c->ases |= MIPS_ASE_MDMX;
390 	if (config1 & MIPS_CONF1_WR)
391 		c->options |= MIPS_CPU_WATCH;
392 	if (config1 & MIPS_CONF1_CA)
393 		c->ases |= MIPS_ASE_MIPS16;
394 	if (config1 & MIPS_CONF1_EP)
395 		c->options |= MIPS_CPU_EJTAG;
396 	if (config1 & MIPS_CONF1_FP) {
397 		c->options |= MIPS_CPU_FPU;
398 		c->options |= MIPS_CPU_32FPR;
399 	}
400 	if (cpu_has_tlb)
401 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
402 
403 	return config1 & MIPS_CONF_M;
404 }
405 
406 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
407 {
408 	unsigned int config2;
409 
410 	config2 = read_c0_config2();
411 
412 	if (config2 & MIPS_CONF2_SL)
413 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
414 
415 	return config2 & MIPS_CONF_M;
416 }
417 
418 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
419 {
420 	unsigned int config3;
421 
422 	config3 = read_c0_config3();
423 
424 	if (config3 & MIPS_CONF3_SM) {
425 		c->ases |= MIPS_ASE_SMARTMIPS;
426 		c->options |= MIPS_CPU_RIXI;
427 	}
428 	if (config3 & MIPS_CONF3_RXI)
429 		c->options |= MIPS_CPU_RIXI;
430 	if (config3 & MIPS_CONF3_DSP)
431 		c->ases |= MIPS_ASE_DSP;
432 	if (config3 & MIPS_CONF3_VINT)
433 		c->options |= MIPS_CPU_VINT;
434 	if (config3 & MIPS_CONF3_VEIC)
435 		c->options |= MIPS_CPU_VEIC;
436 	if (config3 & MIPS_CONF3_MT)
437 		c->ases |= MIPS_ASE_MIPSMT;
438 	if (config3 & MIPS_CONF3_ULRI)
439 		c->options |= MIPS_CPU_ULRI;
440 
441 	return config3 & MIPS_CONF_M;
442 }
443 
444 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
445 {
446 	unsigned int config4;
447 
448 	config4 = read_c0_config4();
449 
450 	if ((config4 & MIPS_CONF4_MMUEXTDEF) == MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT
451 	    && cpu_has_tlb)
452 		c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
453 
454 	c->kscratch_mask = (config4 >> 16) & 0xff;
455 
456 	return config4 & MIPS_CONF_M;
457 }
458 
459 static void __cpuinit decode_configs(struct cpuinfo_mips *c)
460 {
461 	int ok;
462 
463 	/* MIPS32 or MIPS64 compliant CPU.  */
464 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
465 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
466 
467 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
468 
469 	ok = decode_config0(c);			/* Read Config registers.  */
470 	BUG_ON(!ok);				/* Arch spec violation!  */
471 	if (ok)
472 		ok = decode_config1(c);
473 	if (ok)
474 		ok = decode_config2(c);
475 	if (ok)
476 		ok = decode_config3(c);
477 	if (ok)
478 		ok = decode_config4(c);
479 
480 	mips_probe_watch_registers(c);
481 
482 	if (cpu_has_mips_r2)
483 		c->core = read_c0_ebase() & 0x3ff;
484 }
485 
486 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
487 		| MIPS_CPU_COUNTER)
488 
489 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
490 {
491 	switch (c->processor_id & 0xff00) {
492 	case PRID_IMP_R2000:
493 		c->cputype = CPU_R2000;
494 		__cpu_name[cpu] = "R2000";
495 		c->isa_level = MIPS_CPU_ISA_I;
496 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
497 			     MIPS_CPU_NOFPUEX;
498 		if (__cpu_has_fpu())
499 			c->options |= MIPS_CPU_FPU;
500 		c->tlbsize = 64;
501 		break;
502 	case PRID_IMP_R3000:
503 		if ((c->processor_id & 0xff) == PRID_REV_R3000A) {
504 			if (cpu_has_confreg()) {
505 				c->cputype = CPU_R3081E;
506 				__cpu_name[cpu] = "R3081";
507 			} else {
508 				c->cputype = CPU_R3000A;
509 				__cpu_name[cpu] = "R3000A";
510 			}
511 			break;
512 		} else {
513 			c->cputype = CPU_R3000;
514 			__cpu_name[cpu] = "R3000";
515 		}
516 		c->isa_level = MIPS_CPU_ISA_I;
517 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
518 			     MIPS_CPU_NOFPUEX;
519 		if (__cpu_has_fpu())
520 			c->options |= MIPS_CPU_FPU;
521 		c->tlbsize = 64;
522 		break;
523 	case PRID_IMP_R4000:
524 		if (read_c0_config() & CONF_SC) {
525 			if ((c->processor_id & 0xff) >= PRID_REV_R4400) {
526 				c->cputype = CPU_R4400PC;
527 				__cpu_name[cpu] = "R4400PC";
528 			} else {
529 				c->cputype = CPU_R4000PC;
530 				__cpu_name[cpu] = "R4000PC";
531 			}
532 		} else {
533 			if ((c->processor_id & 0xff) >= PRID_REV_R4400) {
534 				c->cputype = CPU_R4400SC;
535 				__cpu_name[cpu] = "R4400SC";
536 			} else {
537 				c->cputype = CPU_R4000SC;
538 				__cpu_name[cpu] = "R4000SC";
539 			}
540 		}
541 
542 		c->isa_level = MIPS_CPU_ISA_III;
543 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
544 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
545 			     MIPS_CPU_LLSC;
546 		c->tlbsize = 48;
547 		break;
548 	case PRID_IMP_VR41XX:
549 		switch (c->processor_id & 0xf0) {
550 		case PRID_REV_VR4111:
551 			c->cputype = CPU_VR4111;
552 			__cpu_name[cpu] = "NEC VR4111";
553 			break;
554 		case PRID_REV_VR4121:
555 			c->cputype = CPU_VR4121;
556 			__cpu_name[cpu] = "NEC VR4121";
557 			break;
558 		case PRID_REV_VR4122:
559 			if ((c->processor_id & 0xf) < 0x3) {
560 				c->cputype = CPU_VR4122;
561 				__cpu_name[cpu] = "NEC VR4122";
562 			} else {
563 				c->cputype = CPU_VR4181A;
564 				__cpu_name[cpu] = "NEC VR4181A";
565 			}
566 			break;
567 		case PRID_REV_VR4130:
568 			if ((c->processor_id & 0xf) < 0x4) {
569 				c->cputype = CPU_VR4131;
570 				__cpu_name[cpu] = "NEC VR4131";
571 			} else {
572 				c->cputype = CPU_VR4133;
573 				__cpu_name[cpu] = "NEC VR4133";
574 			}
575 			break;
576 		default:
577 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
578 			c->cputype = CPU_VR41XX;
579 			__cpu_name[cpu] = "NEC Vr41xx";
580 			break;
581 		}
582 		c->isa_level = MIPS_CPU_ISA_III;
583 		c->options = R4K_OPTS;
584 		c->tlbsize = 32;
585 		break;
586 	case PRID_IMP_R4300:
587 		c->cputype = CPU_R4300;
588 		__cpu_name[cpu] = "R4300";
589 		c->isa_level = MIPS_CPU_ISA_III;
590 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
591 			     MIPS_CPU_LLSC;
592 		c->tlbsize = 32;
593 		break;
594 	case PRID_IMP_R4600:
595 		c->cputype = CPU_R4600;
596 		__cpu_name[cpu] = "R4600";
597 		c->isa_level = MIPS_CPU_ISA_III;
598 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
599 			     MIPS_CPU_LLSC;
600 		c->tlbsize = 48;
601 		break;
602 	#if 0
603 	case PRID_IMP_R4650:
604 		/*
605 		 * This processor doesn't have an MMU, so it's not
606 		 * "real easy" to run Linux on it. It is left purely
607 		 * for documentation.  Commented out because it shares
608 		 * it's c0_prid id number with the TX3900.
609 		 */
610 		c->cputype = CPU_R4650;
611 		__cpu_name[cpu] = "R4650";
612 		c->isa_level = MIPS_CPU_ISA_III;
613 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
614 		c->tlbsize = 48;
615 		break;
616 	#endif
617 	case PRID_IMP_TX39:
618 		c->isa_level = MIPS_CPU_ISA_I;
619 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
620 
621 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
622 			c->cputype = CPU_TX3927;
623 			__cpu_name[cpu] = "TX3927";
624 			c->tlbsize = 64;
625 		} else {
626 			switch (c->processor_id & 0xff) {
627 			case PRID_REV_TX3912:
628 				c->cputype = CPU_TX3912;
629 				__cpu_name[cpu] = "TX3912";
630 				c->tlbsize = 32;
631 				break;
632 			case PRID_REV_TX3922:
633 				c->cputype = CPU_TX3922;
634 				__cpu_name[cpu] = "TX3922";
635 				c->tlbsize = 64;
636 				break;
637 			}
638 		}
639 		break;
640 	case PRID_IMP_R4700:
641 		c->cputype = CPU_R4700;
642 		__cpu_name[cpu] = "R4700";
643 		c->isa_level = MIPS_CPU_ISA_III;
644 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
645 			     MIPS_CPU_LLSC;
646 		c->tlbsize = 48;
647 		break;
648 	case PRID_IMP_TX49:
649 		c->cputype = CPU_TX49XX;
650 		__cpu_name[cpu] = "R49XX";
651 		c->isa_level = MIPS_CPU_ISA_III;
652 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
653 		if (!(c->processor_id & 0x08))
654 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
655 		c->tlbsize = 48;
656 		break;
657 	case PRID_IMP_R5000:
658 		c->cputype = CPU_R5000;
659 		__cpu_name[cpu] = "R5000";
660 		c->isa_level = MIPS_CPU_ISA_IV;
661 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
662 			     MIPS_CPU_LLSC;
663 		c->tlbsize = 48;
664 		break;
665 	case PRID_IMP_R5432:
666 		c->cputype = CPU_R5432;
667 		__cpu_name[cpu] = "R5432";
668 		c->isa_level = MIPS_CPU_ISA_IV;
669 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
670 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
671 		c->tlbsize = 48;
672 		break;
673 	case PRID_IMP_R5500:
674 		c->cputype = CPU_R5500;
675 		__cpu_name[cpu] = "R5500";
676 		c->isa_level = MIPS_CPU_ISA_IV;
677 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
678 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
679 		c->tlbsize = 48;
680 		break;
681 	case PRID_IMP_NEVADA:
682 		c->cputype = CPU_NEVADA;
683 		__cpu_name[cpu] = "Nevada";
684 		c->isa_level = MIPS_CPU_ISA_IV;
685 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
686 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
687 		c->tlbsize = 48;
688 		break;
689 	case PRID_IMP_R6000:
690 		c->cputype = CPU_R6000;
691 		__cpu_name[cpu] = "R6000";
692 		c->isa_level = MIPS_CPU_ISA_II;
693 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
694 			     MIPS_CPU_LLSC;
695 		c->tlbsize = 32;
696 		break;
697 	case PRID_IMP_R6000A:
698 		c->cputype = CPU_R6000A;
699 		__cpu_name[cpu] = "R6000A";
700 		c->isa_level = MIPS_CPU_ISA_II;
701 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
702 			     MIPS_CPU_LLSC;
703 		c->tlbsize = 32;
704 		break;
705 	case PRID_IMP_RM7000:
706 		c->cputype = CPU_RM7000;
707 		__cpu_name[cpu] = "RM7000";
708 		c->isa_level = MIPS_CPU_ISA_IV;
709 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
710 			     MIPS_CPU_LLSC;
711 		/*
712 		 * Undocumented RM7000:  Bit 29 in the info register of
713 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
714 		 * entries.
715 		 *
716 		 * 29      1 =>    64 entry JTLB
717 		 *         0 =>    48 entry JTLB
718 		 */
719 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
720 		break;
721 	case PRID_IMP_RM9000:
722 		c->cputype = CPU_RM9000;
723 		__cpu_name[cpu] = "RM9000";
724 		c->isa_level = MIPS_CPU_ISA_IV;
725 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
726 			     MIPS_CPU_LLSC;
727 		/*
728 		 * Bit 29 in the info register of the RM9000
729 		 * indicates if the TLB has 48 or 64 entries.
730 		 *
731 		 * 29      1 =>    64 entry JTLB
732 		 *         0 =>    48 entry JTLB
733 		 */
734 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
735 		break;
736 	case PRID_IMP_R8000:
737 		c->cputype = CPU_R8000;
738 		__cpu_name[cpu] = "RM8000";
739 		c->isa_level = MIPS_CPU_ISA_IV;
740 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
741 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
742 			     MIPS_CPU_LLSC;
743 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
744 		break;
745 	case PRID_IMP_R10000:
746 		c->cputype = CPU_R10000;
747 		__cpu_name[cpu] = "R10000";
748 		c->isa_level = MIPS_CPU_ISA_IV;
749 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
750 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
751 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
752 			     MIPS_CPU_LLSC;
753 		c->tlbsize = 64;
754 		break;
755 	case PRID_IMP_R12000:
756 		c->cputype = CPU_R12000;
757 		__cpu_name[cpu] = "R12000";
758 		c->isa_level = MIPS_CPU_ISA_IV;
759 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
760 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
761 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
762 			     MIPS_CPU_LLSC;
763 		c->tlbsize = 64;
764 		break;
765 	case PRID_IMP_R14000:
766 		c->cputype = CPU_R14000;
767 		__cpu_name[cpu] = "R14000";
768 		c->isa_level = MIPS_CPU_ISA_IV;
769 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
770 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
771 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
772 			     MIPS_CPU_LLSC;
773 		c->tlbsize = 64;
774 		break;
775 	case PRID_IMP_LOONGSON2:
776 		c->cputype = CPU_LOONGSON2;
777 		__cpu_name[cpu] = "ICT Loongson-2";
778 
779 		switch (c->processor_id & PRID_REV_MASK) {
780 		case PRID_REV_LOONGSON2E:
781 			set_elf_platform(cpu, "loongson2e");
782 			break;
783 		case PRID_REV_LOONGSON2F:
784 			set_elf_platform(cpu, "loongson2f");
785 			break;
786 		}
787 
788 		c->isa_level = MIPS_CPU_ISA_III;
789 		c->options = R4K_OPTS |
790 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
791 			     MIPS_CPU_32FPR;
792 		c->tlbsize = 64;
793 		break;
794 	case PRID_IMP_LOONGSON1:
795 		decode_configs(c);
796 
797 		c->cputype = CPU_LOONGSON1;
798 
799 		switch (c->processor_id & PRID_REV_MASK) {
800 		case PRID_REV_LOONGSON1B:
801 			__cpu_name[cpu] = "Loongson 1B";
802 			break;
803 		}
804 
805 		break;
806 	}
807 }
808 
809 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
810 {
811 	decode_configs(c);
812 	switch (c->processor_id & 0xff00) {
813 	case PRID_IMP_4KC:
814 		c->cputype = CPU_4KC;
815 		__cpu_name[cpu] = "MIPS 4Kc";
816 		break;
817 	case PRID_IMP_4KEC:
818 	case PRID_IMP_4KECR2:
819 		c->cputype = CPU_4KEC;
820 		__cpu_name[cpu] = "MIPS 4KEc";
821 		break;
822 	case PRID_IMP_4KSC:
823 	case PRID_IMP_4KSD:
824 		c->cputype = CPU_4KSC;
825 		__cpu_name[cpu] = "MIPS 4KSc";
826 		break;
827 	case PRID_IMP_5KC:
828 		c->cputype = CPU_5KC;
829 		__cpu_name[cpu] = "MIPS 5Kc";
830 		break;
831 	case PRID_IMP_5KE:
832 		c->cputype = CPU_5KE;
833 		__cpu_name[cpu] = "MIPS 5KE";
834 		break;
835 	case PRID_IMP_20KC:
836 		c->cputype = CPU_20KC;
837 		__cpu_name[cpu] = "MIPS 20Kc";
838 		break;
839 	case PRID_IMP_24K:
840 	case PRID_IMP_24KE:
841 		c->cputype = CPU_24K;
842 		__cpu_name[cpu] = "MIPS 24Kc";
843 		break;
844 	case PRID_IMP_25KF:
845 		c->cputype = CPU_25KF;
846 		__cpu_name[cpu] = "MIPS 25Kc";
847 		break;
848 	case PRID_IMP_34K:
849 		c->cputype = CPU_34K;
850 		__cpu_name[cpu] = "MIPS 34Kc";
851 		break;
852 	case PRID_IMP_74K:
853 		c->cputype = CPU_74K;
854 		__cpu_name[cpu] = "MIPS 74Kc";
855 		break;
856 	case PRID_IMP_M14KC:
857 		c->cputype = CPU_M14KC;
858 		__cpu_name[cpu] = "MIPS M14Kc";
859 		break;
860 	case PRID_IMP_1004K:
861 		c->cputype = CPU_1004K;
862 		__cpu_name[cpu] = "MIPS 1004Kc";
863 		break;
864 	case PRID_IMP_1074K:
865 		c->cputype = CPU_74K;
866 		__cpu_name[cpu] = "MIPS 1074Kc";
867 		break;
868 	}
869 
870 	spram_config();
871 }
872 
873 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
874 {
875 	decode_configs(c);
876 	switch (c->processor_id & 0xff00) {
877 	case PRID_IMP_AU1_REV1:
878 	case PRID_IMP_AU1_REV2:
879 		c->cputype = CPU_ALCHEMY;
880 		switch ((c->processor_id >> 24) & 0xff) {
881 		case 0:
882 			__cpu_name[cpu] = "Au1000";
883 			break;
884 		case 1:
885 			__cpu_name[cpu] = "Au1500";
886 			break;
887 		case 2:
888 			__cpu_name[cpu] = "Au1100";
889 			break;
890 		case 3:
891 			__cpu_name[cpu] = "Au1550";
892 			break;
893 		case 4:
894 			__cpu_name[cpu] = "Au1200";
895 			if ((c->processor_id & 0xff) == 2)
896 				__cpu_name[cpu] = "Au1250";
897 			break;
898 		case 5:
899 			__cpu_name[cpu] = "Au1210";
900 			break;
901 		default:
902 			__cpu_name[cpu] = "Au1xxx";
903 			break;
904 		}
905 		break;
906 	}
907 }
908 
909 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
910 {
911 	decode_configs(c);
912 
913 	switch (c->processor_id & 0xff00) {
914 	case PRID_IMP_SB1:
915 		c->cputype = CPU_SB1;
916 		__cpu_name[cpu] = "SiByte SB1";
917 		/* FPU in pass1 is known to have issues. */
918 		if ((c->processor_id & 0xff) < 0x02)
919 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
920 		break;
921 	case PRID_IMP_SB1A:
922 		c->cputype = CPU_SB1A;
923 		__cpu_name[cpu] = "SiByte SB1A";
924 		break;
925 	}
926 }
927 
928 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
929 {
930 	decode_configs(c);
931 	switch (c->processor_id & 0xff00) {
932 	case PRID_IMP_SR71000:
933 		c->cputype = CPU_SR71000;
934 		__cpu_name[cpu] = "Sandcraft SR71000";
935 		c->scache.ways = 8;
936 		c->tlbsize = 64;
937 		break;
938 	}
939 }
940 
941 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
942 {
943 	decode_configs(c);
944 	switch (c->processor_id & 0xff00) {
945 	case PRID_IMP_PR4450:
946 		c->cputype = CPU_PR4450;
947 		__cpu_name[cpu] = "Philips PR4450";
948 		c->isa_level = MIPS_CPU_ISA_M32R1;
949 		break;
950 	}
951 }
952 
953 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
954 {
955 	decode_configs(c);
956 	switch (c->processor_id & 0xff00) {
957 	case PRID_IMP_BMIPS32_REV4:
958 	case PRID_IMP_BMIPS32_REV8:
959 		c->cputype = CPU_BMIPS32;
960 		__cpu_name[cpu] = "Broadcom BMIPS32";
961 		set_elf_platform(cpu, "bmips32");
962 		break;
963 	case PRID_IMP_BMIPS3300:
964 	case PRID_IMP_BMIPS3300_ALT:
965 	case PRID_IMP_BMIPS3300_BUG:
966 		c->cputype = CPU_BMIPS3300;
967 		__cpu_name[cpu] = "Broadcom BMIPS3300";
968 		set_elf_platform(cpu, "bmips3300");
969 		break;
970 	case PRID_IMP_BMIPS43XX: {
971 		int rev = c->processor_id & 0xff;
972 
973 		if (rev >= PRID_REV_BMIPS4380_LO &&
974 				rev <= PRID_REV_BMIPS4380_HI) {
975 			c->cputype = CPU_BMIPS4380;
976 			__cpu_name[cpu] = "Broadcom BMIPS4380";
977 			set_elf_platform(cpu, "bmips4380");
978 		} else {
979 			c->cputype = CPU_BMIPS4350;
980 			__cpu_name[cpu] = "Broadcom BMIPS4350";
981 			set_elf_platform(cpu, "bmips4350");
982 		}
983 		break;
984 	}
985 	case PRID_IMP_BMIPS5000:
986 		c->cputype = CPU_BMIPS5000;
987 		__cpu_name[cpu] = "Broadcom BMIPS5000";
988 		set_elf_platform(cpu, "bmips5000");
989 		c->options |= MIPS_CPU_ULRI;
990 		break;
991 	}
992 }
993 
994 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
995 {
996 	decode_configs(c);
997 	switch (c->processor_id & 0xff00) {
998 	case PRID_IMP_CAVIUM_CN38XX:
999 	case PRID_IMP_CAVIUM_CN31XX:
1000 	case PRID_IMP_CAVIUM_CN30XX:
1001 		c->cputype = CPU_CAVIUM_OCTEON;
1002 		__cpu_name[cpu] = "Cavium Octeon";
1003 		goto platform;
1004 	case PRID_IMP_CAVIUM_CN58XX:
1005 	case PRID_IMP_CAVIUM_CN56XX:
1006 	case PRID_IMP_CAVIUM_CN50XX:
1007 	case PRID_IMP_CAVIUM_CN52XX:
1008 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1009 		__cpu_name[cpu] = "Cavium Octeon+";
1010 platform:
1011 		set_elf_platform(cpu, "octeon");
1012 		break;
1013 	case PRID_IMP_CAVIUM_CN61XX:
1014 	case PRID_IMP_CAVIUM_CN63XX:
1015 	case PRID_IMP_CAVIUM_CN66XX:
1016 	case PRID_IMP_CAVIUM_CN68XX:
1017 		c->cputype = CPU_CAVIUM_OCTEON2;
1018 		__cpu_name[cpu] = "Cavium Octeon II";
1019 		set_elf_platform(cpu, "octeon2");
1020 		break;
1021 	default:
1022 		printk(KERN_INFO "Unknown Octeon chip!\n");
1023 		c->cputype = CPU_UNKNOWN;
1024 		break;
1025 	}
1026 }
1027 
1028 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1029 {
1030 	decode_configs(c);
1031 	/* JZRISC does not implement the CP0 counter. */
1032 	c->options &= ~MIPS_CPU_COUNTER;
1033 	switch (c->processor_id & 0xff00) {
1034 	case PRID_IMP_JZRISC:
1035 		c->cputype = CPU_JZRISC;
1036 		__cpu_name[cpu] = "Ingenic JZRISC";
1037 		break;
1038 	default:
1039 		panic("Unknown Ingenic Processor ID!");
1040 		break;
1041 	}
1042 }
1043 
1044 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1045 {
1046 	decode_configs(c);
1047 
1048 	if ((c->processor_id & 0xff00) == PRID_IMP_NETLOGIC_AU13XX) {
1049 		c->cputype = CPU_ALCHEMY;
1050 		__cpu_name[cpu] = "Au1300";
1051 		/* following stuff is not for Alchemy */
1052 		return;
1053 	}
1054 
1055 	c->options = (MIPS_CPU_TLB       |
1056 			MIPS_CPU_4KEX    |
1057 			MIPS_CPU_COUNTER |
1058 			MIPS_CPU_DIVEC   |
1059 			MIPS_CPU_WATCH   |
1060 			MIPS_CPU_EJTAG   |
1061 			MIPS_CPU_LLSC);
1062 
1063 	switch (c->processor_id & 0xff00) {
1064 	case PRID_IMP_NETLOGIC_XLP8XX:
1065 	case PRID_IMP_NETLOGIC_XLP3XX:
1066 		c->cputype = CPU_XLP;
1067 		__cpu_name[cpu] = "Netlogic XLP";
1068 		break;
1069 
1070 	case PRID_IMP_NETLOGIC_XLR732:
1071 	case PRID_IMP_NETLOGIC_XLR716:
1072 	case PRID_IMP_NETLOGIC_XLR532:
1073 	case PRID_IMP_NETLOGIC_XLR308:
1074 	case PRID_IMP_NETLOGIC_XLR532C:
1075 	case PRID_IMP_NETLOGIC_XLR516C:
1076 	case PRID_IMP_NETLOGIC_XLR508C:
1077 	case PRID_IMP_NETLOGIC_XLR308C:
1078 		c->cputype = CPU_XLR;
1079 		__cpu_name[cpu] = "Netlogic XLR";
1080 		break;
1081 
1082 	case PRID_IMP_NETLOGIC_XLS608:
1083 	case PRID_IMP_NETLOGIC_XLS408:
1084 	case PRID_IMP_NETLOGIC_XLS404:
1085 	case PRID_IMP_NETLOGIC_XLS208:
1086 	case PRID_IMP_NETLOGIC_XLS204:
1087 	case PRID_IMP_NETLOGIC_XLS108:
1088 	case PRID_IMP_NETLOGIC_XLS104:
1089 	case PRID_IMP_NETLOGIC_XLS616B:
1090 	case PRID_IMP_NETLOGIC_XLS608B:
1091 	case PRID_IMP_NETLOGIC_XLS416B:
1092 	case PRID_IMP_NETLOGIC_XLS412B:
1093 	case PRID_IMP_NETLOGIC_XLS408B:
1094 	case PRID_IMP_NETLOGIC_XLS404B:
1095 		c->cputype = CPU_XLR;
1096 		__cpu_name[cpu] = "Netlogic XLS";
1097 		break;
1098 
1099 	default:
1100 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1101 		       c->processor_id);
1102 		c->cputype = CPU_XLR;
1103 		break;
1104 	}
1105 
1106 	if (c->cputype == CPU_XLP) {
1107 		c->isa_level = MIPS_CPU_ISA_M64R2;
1108 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1109 		/* This will be updated again after all threads are woken up */
1110 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1111 	} else {
1112 		c->isa_level = MIPS_CPU_ISA_M64R1;
1113 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1114 	}
1115 }
1116 
1117 #ifdef CONFIG_64BIT
1118 /* For use by uaccess.h */
1119 u64 __ua_limit;
1120 EXPORT_SYMBOL(__ua_limit);
1121 #endif
1122 
1123 const char *__cpu_name[NR_CPUS];
1124 const char *__elf_platform;
1125 
1126 __cpuinit void cpu_probe(void)
1127 {
1128 	struct cpuinfo_mips *c = &current_cpu_data;
1129 	unsigned int cpu = smp_processor_id();
1130 
1131 	c->processor_id	= PRID_IMP_UNKNOWN;
1132 	c->fpu_id	= FPIR_IMP_NONE;
1133 	c->cputype	= CPU_UNKNOWN;
1134 
1135 	c->processor_id = read_c0_prid();
1136 	switch (c->processor_id & 0xff0000) {
1137 	case PRID_COMP_LEGACY:
1138 		cpu_probe_legacy(c, cpu);
1139 		break;
1140 	case PRID_COMP_MIPS:
1141 		cpu_probe_mips(c, cpu);
1142 		break;
1143 	case PRID_COMP_ALCHEMY:
1144 		cpu_probe_alchemy(c, cpu);
1145 		break;
1146 	case PRID_COMP_SIBYTE:
1147 		cpu_probe_sibyte(c, cpu);
1148 		break;
1149 	case PRID_COMP_BROADCOM:
1150 		cpu_probe_broadcom(c, cpu);
1151 		break;
1152 	case PRID_COMP_SANDCRAFT:
1153 		cpu_probe_sandcraft(c, cpu);
1154 		break;
1155 	case PRID_COMP_NXP:
1156 		cpu_probe_nxp(c, cpu);
1157 		break;
1158 	case PRID_COMP_CAVIUM:
1159 		cpu_probe_cavium(c, cpu);
1160 		break;
1161 	case PRID_COMP_INGENIC:
1162 		cpu_probe_ingenic(c, cpu);
1163 		break;
1164 	case PRID_COMP_NETLOGIC:
1165 		cpu_probe_netlogic(c, cpu);
1166 		break;
1167 	}
1168 
1169 	BUG_ON(!__cpu_name[cpu]);
1170 	BUG_ON(c->cputype == CPU_UNKNOWN);
1171 
1172 	/*
1173 	 * Platform code can force the cpu type to optimize code
1174 	 * generation. In that case be sure the cpu type is correctly
1175 	 * manually setup otherwise it could trigger some nasty bugs.
1176 	 */
1177 	BUG_ON(current_cpu_type() != c->cputype);
1178 
1179 	if (mips_fpu_disabled)
1180 		c->options &= ~MIPS_CPU_FPU;
1181 
1182 	if (mips_dsp_disabled)
1183 		c->ases &= ~MIPS_ASE_DSP;
1184 
1185 	if (c->options & MIPS_CPU_FPU) {
1186 		c->fpu_id = cpu_get_fpu_id();
1187 
1188 		if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
1189 		    c->isa_level == MIPS_CPU_ISA_M32R2 ||
1190 		    c->isa_level == MIPS_CPU_ISA_M64R1 ||
1191 		    c->isa_level == MIPS_CPU_ISA_M64R2) {
1192 			if (c->fpu_id & MIPS_FPIR_3D)
1193 				c->ases |= MIPS_ASE_MIPS3D;
1194 		}
1195 	}
1196 
1197 	if (cpu_has_mips_r2)
1198 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
1199 	else
1200 		c->srsets = 1;
1201 
1202 	cpu_probe_vmbits(c);
1203 
1204 #ifdef CONFIG_64BIT
1205 	if (cpu == 0)
1206 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
1207 #endif
1208 }
1209 
1210 __cpuinit void cpu_report(void)
1211 {
1212 	struct cpuinfo_mips *c = &current_cpu_data;
1213 
1214 	printk(KERN_INFO "CPU revision is: %08x (%s)\n",
1215 	       c->processor_id, cpu_name_string());
1216 	if (c->options & MIPS_CPU_FPU)
1217 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
1218 }
1219