xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 4f3db074)
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/cpu-features.h>
24 #include <asm/cpu-type.h>
25 #include <asm/fpu.h>
26 #include <asm/mipsregs.h>
27 #include <asm/mipsmtregs.h>
28 #include <asm/msa.h>
29 #include <asm/watch.h>
30 #include <asm/elf.h>
31 #include <asm/pgtable-bits.h>
32 #include <asm/spram.h>
33 #include <asm/uaccess.h>
34 
35 /*
36  * Get the FPU Implementation/Revision.
37  */
38 static inline unsigned long cpu_get_fpu_id(void)
39 {
40 	unsigned long tmp, fpu_id;
41 
42 	tmp = read_c0_status();
43 	__enable_fpu(FPU_AS_IS);
44 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
45 	write_c0_status(tmp);
46 	return fpu_id;
47 }
48 
49 /*
50  * Check if the CPU has an external FPU.
51  */
52 static inline int __cpu_has_fpu(void)
53 {
54 	return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
55 }
56 
57 static inline unsigned long cpu_get_msa_id(void)
58 {
59 	unsigned long status, msa_id;
60 
61 	status = read_c0_status();
62 	__enable_fpu(FPU_64BIT);
63 	enable_msa();
64 	msa_id = read_msa_ir();
65 	disable_msa();
66 	write_c0_status(status);
67 	return msa_id;
68 }
69 
70 /*
71  * Determine the FCSR mask for FPU hardware.
72  */
73 static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_mips *c)
74 {
75 	unsigned long sr, mask, fcsr, fcsr0, fcsr1;
76 
77 	mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
78 
79 	sr = read_c0_status();
80 	__enable_fpu(FPU_AS_IS);
81 
82 	fcsr = read_32bit_cp1_register(CP1_STATUS);
83 
84 	fcsr0 = fcsr & mask;
85 	write_32bit_cp1_register(CP1_STATUS, fcsr0);
86 	fcsr0 = read_32bit_cp1_register(CP1_STATUS);
87 
88 	fcsr1 = fcsr | ~mask;
89 	write_32bit_cp1_register(CP1_STATUS, fcsr1);
90 	fcsr1 = read_32bit_cp1_register(CP1_STATUS);
91 
92 	write_32bit_cp1_register(CP1_STATUS, fcsr);
93 
94 	write_c0_status(sr);
95 
96 	c->fpu_msk31 = ~(fcsr0 ^ fcsr1) & ~mask;
97 }
98 
99 /*
100  * Set the FIR feature flags for the FPU emulator.
101  */
102 static void cpu_set_nofpu_id(struct cpuinfo_mips *c)
103 {
104 	u32 value;
105 
106 	value = 0;
107 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
108 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
109 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
110 		value |= MIPS_FPIR_D | MIPS_FPIR_S;
111 	if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
112 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
113 		value |= MIPS_FPIR_F64 | MIPS_FPIR_L | MIPS_FPIR_W;
114 	c->fpu_id = value;
115 }
116 
117 /* Determined FPU emulator mask to use for the boot CPU with "nofpu".  */
118 static unsigned int mips_nofpu_msk31;
119 
120 /*
121  * Set options for FPU hardware.
122  */
123 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
124 {
125 	c->fpu_id = cpu_get_fpu_id();
126 	mips_nofpu_msk31 = c->fpu_msk31;
127 
128 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
129 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
130 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
131 		if (c->fpu_id & MIPS_FPIR_3D)
132 			c->ases |= MIPS_ASE_MIPS3D;
133 		if (c->fpu_id & MIPS_FPIR_FREP)
134 			c->options |= MIPS_CPU_FRE;
135 	}
136 
137 	cpu_set_fpu_fcsr_mask(c);
138 }
139 
140 /*
141  * Set options for the FPU emulator.
142  */
143 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
144 {
145 	c->options &= ~MIPS_CPU_FPU;
146 	c->fpu_msk31 = mips_nofpu_msk31;
147 
148 	cpu_set_nofpu_id(c);
149 }
150 
151 static int mips_fpu_disabled;
152 
153 static int __init fpu_disable(char *s)
154 {
155 	cpu_set_nofpu_opts(&boot_cpu_data);
156 	mips_fpu_disabled = 1;
157 
158 	return 1;
159 }
160 
161 __setup("nofpu", fpu_disable);
162 
163 int mips_dsp_disabled;
164 
165 static int __init dsp_disable(char *s)
166 {
167 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
168 	mips_dsp_disabled = 1;
169 
170 	return 1;
171 }
172 
173 __setup("nodsp", dsp_disable);
174 
175 static int mips_htw_disabled;
176 
177 static int __init htw_disable(char *s)
178 {
179 	mips_htw_disabled = 1;
180 	cpu_data[0].options &= ~MIPS_CPU_HTW;
181 	write_c0_pwctl(read_c0_pwctl() &
182 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
183 
184 	return 1;
185 }
186 
187 __setup("nohtw", htw_disable);
188 
189 static int mips_ftlb_disabled;
190 static int mips_has_ftlb_configured;
191 
192 static void set_ftlb_enable(struct cpuinfo_mips *c, int enable);
193 
194 static int __init ftlb_disable(char *s)
195 {
196 	unsigned int config4, mmuextdef;
197 
198 	/*
199 	 * If the core hasn't done any FTLB configuration, there is nothing
200 	 * for us to do here.
201 	 */
202 	if (!mips_has_ftlb_configured)
203 		return 1;
204 
205 	/* Disable it in the boot cpu */
206 	set_ftlb_enable(&cpu_data[0], 0);
207 
208 	back_to_back_c0_hazard();
209 
210 	config4 = read_c0_config4();
211 
212 	/* Check that FTLB has been disabled */
213 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
214 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
215 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
216 		/* This should never happen */
217 		pr_warn("FTLB could not be disabled!\n");
218 		return 1;
219 	}
220 
221 	mips_ftlb_disabled = 1;
222 	mips_has_ftlb_configured = 0;
223 
224 	/*
225 	 * noftlb is mainly used for debug purposes so print
226 	 * an informative message instead of using pr_debug()
227 	 */
228 	pr_info("FTLB has been disabled\n");
229 
230 	/*
231 	 * Some of these bits are duplicated in the decode_config4.
232 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
233 	 * once FTLB has been disabled so undo what decode_config4 did.
234 	 */
235 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
236 			       cpu_data[0].tlbsizeftlbsets;
237 	cpu_data[0].tlbsizeftlbsets = 0;
238 	cpu_data[0].tlbsizeftlbways = 0;
239 
240 	return 1;
241 }
242 
243 __setup("noftlb", ftlb_disable);
244 
245 
246 static inline void check_errata(void)
247 {
248 	struct cpuinfo_mips *c = &current_cpu_data;
249 
250 	switch (current_cpu_type()) {
251 	case CPU_34K:
252 		/*
253 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
254 		 * This code only handles VPE0, any SMP/RTOS code
255 		 * making use of VPE1 will be responsable for that VPE.
256 		 */
257 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
258 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
259 		break;
260 	default:
261 		break;
262 	}
263 }
264 
265 void __init check_bugs32(void)
266 {
267 	check_errata();
268 }
269 
270 /*
271  * Probe whether cpu has config register by trying to play with
272  * alternate cache bit and see whether it matters.
273  * It's used by cpu_probe to distinguish between R3000A and R3081.
274  */
275 static inline int cpu_has_confreg(void)
276 {
277 #ifdef CONFIG_CPU_R3000
278 	extern unsigned long r3k_cache_size(unsigned long);
279 	unsigned long size1, size2;
280 	unsigned long cfg = read_c0_conf();
281 
282 	size1 = r3k_cache_size(ST0_ISC);
283 	write_c0_conf(cfg ^ R30XX_CONF_AC);
284 	size2 = r3k_cache_size(ST0_ISC);
285 	write_c0_conf(cfg);
286 	return size1 != size2;
287 #else
288 	return 0;
289 #endif
290 }
291 
292 static inline void set_elf_platform(int cpu, const char *plat)
293 {
294 	if (cpu == 0)
295 		__elf_platform = plat;
296 }
297 
298 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
299 {
300 #ifdef __NEED_VMBITS_PROBE
301 	write_c0_entryhi(0x3fffffffffffe000ULL);
302 	back_to_back_c0_hazard();
303 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
304 #endif
305 }
306 
307 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
308 {
309 	switch (isa) {
310 	case MIPS_CPU_ISA_M64R2:
311 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
312 	case MIPS_CPU_ISA_M64R1:
313 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
314 	case MIPS_CPU_ISA_V:
315 		c->isa_level |= MIPS_CPU_ISA_V;
316 	case MIPS_CPU_ISA_IV:
317 		c->isa_level |= MIPS_CPU_ISA_IV;
318 	case MIPS_CPU_ISA_III:
319 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
320 		break;
321 
322 	/* R6 incompatible with everything else */
323 	case MIPS_CPU_ISA_M64R6:
324 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
325 	case MIPS_CPU_ISA_M32R6:
326 		c->isa_level |= MIPS_CPU_ISA_M32R6;
327 		/* Break here so we don't add incompatible ISAs */
328 		break;
329 	case MIPS_CPU_ISA_M32R2:
330 		c->isa_level |= MIPS_CPU_ISA_M32R2;
331 	case MIPS_CPU_ISA_M32R1:
332 		c->isa_level |= MIPS_CPU_ISA_M32R1;
333 	case MIPS_CPU_ISA_II:
334 		c->isa_level |= MIPS_CPU_ISA_II;
335 		break;
336 	}
337 }
338 
339 static char unknown_isa[] = KERN_ERR \
340 	"Unsupported ISA type, c0.config0: %d.";
341 
342 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
343 {
344 
345 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
346 
347 	/*
348 	 * 0 = All TLBWR instructions go to FTLB
349 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
350 	 * FTLB and 1 goes to the VTLB.
351 	 * 2 = 7:1: As above with 7:1 ratio.
352 	 * 3 = 3:1: As above with 3:1 ratio.
353 	 *
354 	 * Use the linear midpoint as the probability threshold.
355 	 */
356 	if (probability >= 12)
357 		return 1;
358 	else if (probability >= 6)
359 		return 2;
360 	else
361 		/*
362 		 * So FTLB is less than 4 times bigger than VTLB.
363 		 * A 3:1 ratio can still be useful though.
364 		 */
365 		return 3;
366 }
367 
368 static void set_ftlb_enable(struct cpuinfo_mips *c, int enable)
369 {
370 	unsigned int config6;
371 
372 	/* It's implementation dependent how the FTLB can be enabled */
373 	switch (c->cputype) {
374 	case CPU_PROAPTIV:
375 	case CPU_P5600:
376 		/* proAptiv & related cores use Config6 to enable the FTLB */
377 		config6 = read_c0_config6();
378 		/* Clear the old probability value */
379 		config6 &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
380 		if (enable)
381 			/* Enable FTLB */
382 			write_c0_config6(config6 |
383 					 (calculate_ftlb_probability(c)
384 					  << MIPS_CONF6_FTLBP_SHIFT)
385 					 | MIPS_CONF6_FTLBEN);
386 		else
387 			/* Disable FTLB */
388 			write_c0_config6(config6 &  ~MIPS_CONF6_FTLBEN);
389 		back_to_back_c0_hazard();
390 		break;
391 	}
392 }
393 
394 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
395 {
396 	unsigned int config0;
397 	int isa;
398 
399 	config0 = read_c0_config();
400 
401 	/*
402 	 * Look for Standard TLB or Dual VTLB and FTLB
403 	 */
404 	if ((((config0 & MIPS_CONF_MT) >> 7) == 1) ||
405 	    (((config0 & MIPS_CONF_MT) >> 7) == 4))
406 		c->options |= MIPS_CPU_TLB;
407 
408 	isa = (config0 & MIPS_CONF_AT) >> 13;
409 	switch (isa) {
410 	case 0:
411 		switch ((config0 & MIPS_CONF_AR) >> 10) {
412 		case 0:
413 			set_isa(c, MIPS_CPU_ISA_M32R1);
414 			break;
415 		case 1:
416 			set_isa(c, MIPS_CPU_ISA_M32R2);
417 			break;
418 		case 2:
419 			set_isa(c, MIPS_CPU_ISA_M32R6);
420 			break;
421 		default:
422 			goto unknown;
423 		}
424 		break;
425 	case 2:
426 		switch ((config0 & MIPS_CONF_AR) >> 10) {
427 		case 0:
428 			set_isa(c, MIPS_CPU_ISA_M64R1);
429 			break;
430 		case 1:
431 			set_isa(c, MIPS_CPU_ISA_M64R2);
432 			break;
433 		case 2:
434 			set_isa(c, MIPS_CPU_ISA_M64R6);
435 			break;
436 		default:
437 			goto unknown;
438 		}
439 		break;
440 	default:
441 		goto unknown;
442 	}
443 
444 	return config0 & MIPS_CONF_M;
445 
446 unknown:
447 	panic(unknown_isa, config0);
448 }
449 
450 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
451 {
452 	unsigned int config1;
453 
454 	config1 = read_c0_config1();
455 
456 	if (config1 & MIPS_CONF1_MD)
457 		c->ases |= MIPS_ASE_MDMX;
458 	if (config1 & MIPS_CONF1_WR)
459 		c->options |= MIPS_CPU_WATCH;
460 	if (config1 & MIPS_CONF1_CA)
461 		c->ases |= MIPS_ASE_MIPS16;
462 	if (config1 & MIPS_CONF1_EP)
463 		c->options |= MIPS_CPU_EJTAG;
464 	if (config1 & MIPS_CONF1_FP) {
465 		c->options |= MIPS_CPU_FPU;
466 		c->options |= MIPS_CPU_32FPR;
467 	}
468 	if (cpu_has_tlb) {
469 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
470 		c->tlbsizevtlb = c->tlbsize;
471 		c->tlbsizeftlbsets = 0;
472 	}
473 
474 	return config1 & MIPS_CONF_M;
475 }
476 
477 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
478 {
479 	unsigned int config2;
480 
481 	config2 = read_c0_config2();
482 
483 	if (config2 & MIPS_CONF2_SL)
484 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
485 
486 	return config2 & MIPS_CONF_M;
487 }
488 
489 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
490 {
491 	unsigned int config3;
492 
493 	config3 = read_c0_config3();
494 
495 	if (config3 & MIPS_CONF3_SM) {
496 		c->ases |= MIPS_ASE_SMARTMIPS;
497 		c->options |= MIPS_CPU_RIXI;
498 	}
499 	if (config3 & MIPS_CONF3_RXI)
500 		c->options |= MIPS_CPU_RIXI;
501 	if (config3 & MIPS_CONF3_DSP)
502 		c->ases |= MIPS_ASE_DSP;
503 	if (config3 & MIPS_CONF3_DSP2P)
504 		c->ases |= MIPS_ASE_DSP2P;
505 	if (config3 & MIPS_CONF3_VINT)
506 		c->options |= MIPS_CPU_VINT;
507 	if (config3 & MIPS_CONF3_VEIC)
508 		c->options |= MIPS_CPU_VEIC;
509 	if (config3 & MIPS_CONF3_MT)
510 		c->ases |= MIPS_ASE_MIPSMT;
511 	if (config3 & MIPS_CONF3_ULRI)
512 		c->options |= MIPS_CPU_ULRI;
513 	if (config3 & MIPS_CONF3_ISA)
514 		c->options |= MIPS_CPU_MICROMIPS;
515 	if (config3 & MIPS_CONF3_VZ)
516 		c->ases |= MIPS_ASE_VZ;
517 	if (config3 & MIPS_CONF3_SC)
518 		c->options |= MIPS_CPU_SEGMENTS;
519 	if (config3 & MIPS_CONF3_MSA)
520 		c->ases |= MIPS_ASE_MSA;
521 	/* Only tested on 32-bit cores */
522 	if ((config3 & MIPS_CONF3_PW) && config_enabled(CONFIG_32BIT)) {
523 		c->htw_seq = 0;
524 		c->options |= MIPS_CPU_HTW;
525 	}
526 	if (config3 & MIPS_CONF3_CDMM)
527 		c->options |= MIPS_CPU_CDMM;
528 
529 	return config3 & MIPS_CONF_M;
530 }
531 
532 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
533 {
534 	unsigned int config4;
535 	unsigned int newcf4;
536 	unsigned int mmuextdef;
537 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
538 
539 	config4 = read_c0_config4();
540 
541 	if (cpu_has_tlb) {
542 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
543 			c->options |= MIPS_CPU_TLBINV;
544 		mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
545 		switch (mmuextdef) {
546 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
547 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
548 			c->tlbsizevtlb = c->tlbsize;
549 			break;
550 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
551 			c->tlbsizevtlb +=
552 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
553 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
554 			c->tlbsize = c->tlbsizevtlb;
555 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
556 			/* fall through */
557 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
558 			if (mips_ftlb_disabled)
559 				break;
560 			newcf4 = (config4 & ~ftlb_page) |
561 				(page_size_ftlb(mmuextdef) <<
562 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
563 			write_c0_config4(newcf4);
564 			back_to_back_c0_hazard();
565 			config4 = read_c0_config4();
566 			if (config4 != newcf4) {
567 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
568 				       PAGE_SIZE, config4);
569 				/* Switch FTLB off */
570 				set_ftlb_enable(c, 0);
571 				break;
572 			}
573 			c->tlbsizeftlbsets = 1 <<
574 				((config4 & MIPS_CONF4_FTLBSETS) >>
575 				 MIPS_CONF4_FTLBSETS_SHIFT);
576 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
577 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
578 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
579 			mips_has_ftlb_configured = 1;
580 			break;
581 		}
582 	}
583 
584 	c->kscratch_mask = (config4 >> 16) & 0xff;
585 
586 	return config4 & MIPS_CONF_M;
587 }
588 
589 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
590 {
591 	unsigned int config5;
592 
593 	config5 = read_c0_config5();
594 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
595 	write_c0_config5(config5);
596 
597 	if (config5 & MIPS_CONF5_EVA)
598 		c->options |= MIPS_CPU_EVA;
599 	if (config5 & MIPS_CONF5_MRP)
600 		c->options |= MIPS_CPU_MAAR;
601 	if (config5 & MIPS_CONF5_LLB)
602 		c->options |= MIPS_CPU_RW_LLB;
603 #ifdef CONFIG_XPA
604 	if (config5 & MIPS_CONF5_MVH)
605 		c->options |= MIPS_CPU_XPA;
606 #endif
607 
608 	return config5 & MIPS_CONF_M;
609 }
610 
611 static void decode_configs(struct cpuinfo_mips *c)
612 {
613 	int ok;
614 
615 	/* MIPS32 or MIPS64 compliant CPU.  */
616 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
617 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
618 
619 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
620 
621 	/* Enable FTLB if present and not disabled */
622 	set_ftlb_enable(c, !mips_ftlb_disabled);
623 
624 	ok = decode_config0(c);			/* Read Config registers.  */
625 	BUG_ON(!ok);				/* Arch spec violation!	 */
626 	if (ok)
627 		ok = decode_config1(c);
628 	if (ok)
629 		ok = decode_config2(c);
630 	if (ok)
631 		ok = decode_config3(c);
632 	if (ok)
633 		ok = decode_config4(c);
634 	if (ok)
635 		ok = decode_config5(c);
636 
637 	mips_probe_watch_registers(c);
638 
639 	if (cpu_has_rixi) {
640 		/* Enable the RIXI exceptions */
641 		set_c0_pagegrain(PG_IEC);
642 		back_to_back_c0_hazard();
643 		/* Verify the IEC bit is set */
644 		if (read_c0_pagegrain() & PG_IEC)
645 			c->options |= MIPS_CPU_RIXIEX;
646 	}
647 
648 #ifndef CONFIG_MIPS_CPS
649 	if (cpu_has_mips_r2_r6) {
650 		c->core = get_ebase_cpunum();
651 		if (cpu_has_mipsmt)
652 			c->core >>= fls(core_nvpes()) - 1;
653 	}
654 #endif
655 }
656 
657 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
658 		| MIPS_CPU_COUNTER)
659 
660 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
661 {
662 	switch (c->processor_id & PRID_IMP_MASK) {
663 	case PRID_IMP_R2000:
664 		c->cputype = CPU_R2000;
665 		__cpu_name[cpu] = "R2000";
666 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
667 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
668 			     MIPS_CPU_NOFPUEX;
669 		if (__cpu_has_fpu())
670 			c->options |= MIPS_CPU_FPU;
671 		c->tlbsize = 64;
672 		break;
673 	case PRID_IMP_R3000:
674 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
675 			if (cpu_has_confreg()) {
676 				c->cputype = CPU_R3081E;
677 				__cpu_name[cpu] = "R3081";
678 			} else {
679 				c->cputype = CPU_R3000A;
680 				__cpu_name[cpu] = "R3000A";
681 			}
682 		} else {
683 			c->cputype = CPU_R3000;
684 			__cpu_name[cpu] = "R3000";
685 		}
686 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
687 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
688 			     MIPS_CPU_NOFPUEX;
689 		if (__cpu_has_fpu())
690 			c->options |= MIPS_CPU_FPU;
691 		c->tlbsize = 64;
692 		break;
693 	case PRID_IMP_R4000:
694 		if (read_c0_config() & CONF_SC) {
695 			if ((c->processor_id & PRID_REV_MASK) >=
696 			    PRID_REV_R4400) {
697 				c->cputype = CPU_R4400PC;
698 				__cpu_name[cpu] = "R4400PC";
699 			} else {
700 				c->cputype = CPU_R4000PC;
701 				__cpu_name[cpu] = "R4000PC";
702 			}
703 		} else {
704 			int cca = read_c0_config() & CONF_CM_CMASK;
705 			int mc;
706 
707 			/*
708 			 * SC and MC versions can't be reliably told apart,
709 			 * but only the latter support coherent caching
710 			 * modes so assume the firmware has set the KSEG0
711 			 * coherency attribute reasonably (if uncached, we
712 			 * assume SC).
713 			 */
714 			switch (cca) {
715 			case CONF_CM_CACHABLE_CE:
716 			case CONF_CM_CACHABLE_COW:
717 			case CONF_CM_CACHABLE_CUW:
718 				mc = 1;
719 				break;
720 			default:
721 				mc = 0;
722 				break;
723 			}
724 			if ((c->processor_id & PRID_REV_MASK) >=
725 			    PRID_REV_R4400) {
726 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
727 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
728 			} else {
729 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
730 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
731 			}
732 		}
733 
734 		set_isa(c, MIPS_CPU_ISA_III);
735 		c->fpu_msk31 |= FPU_CSR_CONDX;
736 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
737 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
738 			     MIPS_CPU_LLSC;
739 		c->tlbsize = 48;
740 		break;
741 	case PRID_IMP_VR41XX:
742 		set_isa(c, MIPS_CPU_ISA_III);
743 		c->fpu_msk31 |= FPU_CSR_CONDX;
744 		c->options = R4K_OPTS;
745 		c->tlbsize = 32;
746 		switch (c->processor_id & 0xf0) {
747 		case PRID_REV_VR4111:
748 			c->cputype = CPU_VR4111;
749 			__cpu_name[cpu] = "NEC VR4111";
750 			break;
751 		case PRID_REV_VR4121:
752 			c->cputype = CPU_VR4121;
753 			__cpu_name[cpu] = "NEC VR4121";
754 			break;
755 		case PRID_REV_VR4122:
756 			if ((c->processor_id & 0xf) < 0x3) {
757 				c->cputype = CPU_VR4122;
758 				__cpu_name[cpu] = "NEC VR4122";
759 			} else {
760 				c->cputype = CPU_VR4181A;
761 				__cpu_name[cpu] = "NEC VR4181A";
762 			}
763 			break;
764 		case PRID_REV_VR4130:
765 			if ((c->processor_id & 0xf) < 0x4) {
766 				c->cputype = CPU_VR4131;
767 				__cpu_name[cpu] = "NEC VR4131";
768 			} else {
769 				c->cputype = CPU_VR4133;
770 				c->options |= MIPS_CPU_LLSC;
771 				__cpu_name[cpu] = "NEC VR4133";
772 			}
773 			break;
774 		default:
775 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
776 			c->cputype = CPU_VR41XX;
777 			__cpu_name[cpu] = "NEC Vr41xx";
778 			break;
779 		}
780 		break;
781 	case PRID_IMP_R4300:
782 		c->cputype = CPU_R4300;
783 		__cpu_name[cpu] = "R4300";
784 		set_isa(c, MIPS_CPU_ISA_III);
785 		c->fpu_msk31 |= FPU_CSR_CONDX;
786 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
787 			     MIPS_CPU_LLSC;
788 		c->tlbsize = 32;
789 		break;
790 	case PRID_IMP_R4600:
791 		c->cputype = CPU_R4600;
792 		__cpu_name[cpu] = "R4600";
793 		set_isa(c, MIPS_CPU_ISA_III);
794 		c->fpu_msk31 |= FPU_CSR_CONDX;
795 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
796 			     MIPS_CPU_LLSC;
797 		c->tlbsize = 48;
798 		break;
799 	#if 0
800 	case PRID_IMP_R4650:
801 		/*
802 		 * This processor doesn't have an MMU, so it's not
803 		 * "real easy" to run Linux on it. It is left purely
804 		 * for documentation.  Commented out because it shares
805 		 * it's c0_prid id number with the TX3900.
806 		 */
807 		c->cputype = CPU_R4650;
808 		__cpu_name[cpu] = "R4650";
809 		set_isa(c, MIPS_CPU_ISA_III);
810 		c->fpu_msk31 |= FPU_CSR_CONDX;
811 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
812 		c->tlbsize = 48;
813 		break;
814 	#endif
815 	case PRID_IMP_TX39:
816 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
817 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
818 
819 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
820 			c->cputype = CPU_TX3927;
821 			__cpu_name[cpu] = "TX3927";
822 			c->tlbsize = 64;
823 		} else {
824 			switch (c->processor_id & PRID_REV_MASK) {
825 			case PRID_REV_TX3912:
826 				c->cputype = CPU_TX3912;
827 				__cpu_name[cpu] = "TX3912";
828 				c->tlbsize = 32;
829 				break;
830 			case PRID_REV_TX3922:
831 				c->cputype = CPU_TX3922;
832 				__cpu_name[cpu] = "TX3922";
833 				c->tlbsize = 64;
834 				break;
835 			}
836 		}
837 		break;
838 	case PRID_IMP_R4700:
839 		c->cputype = CPU_R4700;
840 		__cpu_name[cpu] = "R4700";
841 		set_isa(c, MIPS_CPU_ISA_III);
842 		c->fpu_msk31 |= FPU_CSR_CONDX;
843 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
844 			     MIPS_CPU_LLSC;
845 		c->tlbsize = 48;
846 		break;
847 	case PRID_IMP_TX49:
848 		c->cputype = CPU_TX49XX;
849 		__cpu_name[cpu] = "R49XX";
850 		set_isa(c, MIPS_CPU_ISA_III);
851 		c->fpu_msk31 |= FPU_CSR_CONDX;
852 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
853 		if (!(c->processor_id & 0x08))
854 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
855 		c->tlbsize = 48;
856 		break;
857 	case PRID_IMP_R5000:
858 		c->cputype = CPU_R5000;
859 		__cpu_name[cpu] = "R5000";
860 		set_isa(c, MIPS_CPU_ISA_IV);
861 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
862 			     MIPS_CPU_LLSC;
863 		c->tlbsize = 48;
864 		break;
865 	case PRID_IMP_R5432:
866 		c->cputype = CPU_R5432;
867 		__cpu_name[cpu] = "R5432";
868 		set_isa(c, MIPS_CPU_ISA_IV);
869 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
870 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
871 		c->tlbsize = 48;
872 		break;
873 	case PRID_IMP_R5500:
874 		c->cputype = CPU_R5500;
875 		__cpu_name[cpu] = "R5500";
876 		set_isa(c, MIPS_CPU_ISA_IV);
877 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
878 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
879 		c->tlbsize = 48;
880 		break;
881 	case PRID_IMP_NEVADA:
882 		c->cputype = CPU_NEVADA;
883 		__cpu_name[cpu] = "Nevada";
884 		set_isa(c, MIPS_CPU_ISA_IV);
885 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
886 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
887 		c->tlbsize = 48;
888 		break;
889 	case PRID_IMP_R6000:
890 		c->cputype = CPU_R6000;
891 		__cpu_name[cpu] = "R6000";
892 		set_isa(c, MIPS_CPU_ISA_II);
893 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
894 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
895 			     MIPS_CPU_LLSC;
896 		c->tlbsize = 32;
897 		break;
898 	case PRID_IMP_R6000A:
899 		c->cputype = CPU_R6000A;
900 		__cpu_name[cpu] = "R6000A";
901 		set_isa(c, MIPS_CPU_ISA_II);
902 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
903 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
904 			     MIPS_CPU_LLSC;
905 		c->tlbsize = 32;
906 		break;
907 	case PRID_IMP_RM7000:
908 		c->cputype = CPU_RM7000;
909 		__cpu_name[cpu] = "RM7000";
910 		set_isa(c, MIPS_CPU_ISA_IV);
911 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
912 			     MIPS_CPU_LLSC;
913 		/*
914 		 * Undocumented RM7000:	 Bit 29 in the info register of
915 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
916 		 * entries.
917 		 *
918 		 * 29	   1 =>	   64 entry JTLB
919 		 *	   0 =>	   48 entry JTLB
920 		 */
921 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
922 		break;
923 	case PRID_IMP_R8000:
924 		c->cputype = CPU_R8000;
925 		__cpu_name[cpu] = "RM8000";
926 		set_isa(c, MIPS_CPU_ISA_IV);
927 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
928 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
929 			     MIPS_CPU_LLSC;
930 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
931 		break;
932 	case PRID_IMP_R10000:
933 		c->cputype = CPU_R10000;
934 		__cpu_name[cpu] = "R10000";
935 		set_isa(c, MIPS_CPU_ISA_IV);
936 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
937 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
938 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
939 			     MIPS_CPU_LLSC;
940 		c->tlbsize = 64;
941 		break;
942 	case PRID_IMP_R12000:
943 		c->cputype = CPU_R12000;
944 		__cpu_name[cpu] = "R12000";
945 		set_isa(c, MIPS_CPU_ISA_IV);
946 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
947 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
948 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
949 			     MIPS_CPU_LLSC;
950 		c->tlbsize = 64;
951 		break;
952 	case PRID_IMP_R14000:
953 		if (((c->processor_id >> 4) & 0x0f) > 2) {
954 			c->cputype = CPU_R16000;
955 			__cpu_name[cpu] = "R16000";
956 		} else {
957 			c->cputype = CPU_R14000;
958 			__cpu_name[cpu] = "R14000";
959 		}
960 		set_isa(c, MIPS_CPU_ISA_IV);
961 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
962 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
963 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
964 			     MIPS_CPU_LLSC;
965 		c->tlbsize = 64;
966 		break;
967 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
968 		switch (c->processor_id & PRID_REV_MASK) {
969 		case PRID_REV_LOONGSON2E:
970 			c->cputype = CPU_LOONGSON2;
971 			__cpu_name[cpu] = "ICT Loongson-2";
972 			set_elf_platform(cpu, "loongson2e");
973 			set_isa(c, MIPS_CPU_ISA_III);
974 			c->fpu_msk31 |= FPU_CSR_CONDX;
975 			break;
976 		case PRID_REV_LOONGSON2F:
977 			c->cputype = CPU_LOONGSON2;
978 			__cpu_name[cpu] = "ICT Loongson-2";
979 			set_elf_platform(cpu, "loongson2f");
980 			set_isa(c, MIPS_CPU_ISA_III);
981 			c->fpu_msk31 |= FPU_CSR_CONDX;
982 			break;
983 		case PRID_REV_LOONGSON3A:
984 			c->cputype = CPU_LOONGSON3;
985 			__cpu_name[cpu] = "ICT Loongson-3";
986 			set_elf_platform(cpu, "loongson3a");
987 			set_isa(c, MIPS_CPU_ISA_M64R1);
988 			break;
989 		case PRID_REV_LOONGSON3B_R1:
990 		case PRID_REV_LOONGSON3B_R2:
991 			c->cputype = CPU_LOONGSON3;
992 			__cpu_name[cpu] = "ICT Loongson-3";
993 			set_elf_platform(cpu, "loongson3b");
994 			set_isa(c, MIPS_CPU_ISA_M64R1);
995 			break;
996 		}
997 
998 		c->options = R4K_OPTS |
999 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1000 			     MIPS_CPU_32FPR;
1001 		c->tlbsize = 64;
1002 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1003 		break;
1004 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1005 		decode_configs(c);
1006 
1007 		c->cputype = CPU_LOONGSON1;
1008 
1009 		switch (c->processor_id & PRID_REV_MASK) {
1010 		case PRID_REV_LOONGSON1B:
1011 			__cpu_name[cpu] = "Loongson 1B";
1012 			break;
1013 		}
1014 
1015 		break;
1016 	}
1017 }
1018 
1019 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1020 {
1021 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1022 	switch (c->processor_id & PRID_IMP_MASK) {
1023 	case PRID_IMP_QEMU_GENERIC:
1024 		c->writecombine = _CACHE_UNCACHED;
1025 		c->cputype = CPU_QEMU_GENERIC;
1026 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1027 		break;
1028 	case PRID_IMP_4KC:
1029 		c->cputype = CPU_4KC;
1030 		c->writecombine = _CACHE_UNCACHED;
1031 		__cpu_name[cpu] = "MIPS 4Kc";
1032 		break;
1033 	case PRID_IMP_4KEC:
1034 	case PRID_IMP_4KECR2:
1035 		c->cputype = CPU_4KEC;
1036 		c->writecombine = _CACHE_UNCACHED;
1037 		__cpu_name[cpu] = "MIPS 4KEc";
1038 		break;
1039 	case PRID_IMP_4KSC:
1040 	case PRID_IMP_4KSD:
1041 		c->cputype = CPU_4KSC;
1042 		c->writecombine = _CACHE_UNCACHED;
1043 		__cpu_name[cpu] = "MIPS 4KSc";
1044 		break;
1045 	case PRID_IMP_5KC:
1046 		c->cputype = CPU_5KC;
1047 		c->writecombine = _CACHE_UNCACHED;
1048 		__cpu_name[cpu] = "MIPS 5Kc";
1049 		break;
1050 	case PRID_IMP_5KE:
1051 		c->cputype = CPU_5KE;
1052 		c->writecombine = _CACHE_UNCACHED;
1053 		__cpu_name[cpu] = "MIPS 5KE";
1054 		break;
1055 	case PRID_IMP_20KC:
1056 		c->cputype = CPU_20KC;
1057 		c->writecombine = _CACHE_UNCACHED;
1058 		__cpu_name[cpu] = "MIPS 20Kc";
1059 		break;
1060 	case PRID_IMP_24K:
1061 		c->cputype = CPU_24K;
1062 		c->writecombine = _CACHE_UNCACHED;
1063 		__cpu_name[cpu] = "MIPS 24Kc";
1064 		break;
1065 	case PRID_IMP_24KE:
1066 		c->cputype = CPU_24K;
1067 		c->writecombine = _CACHE_UNCACHED;
1068 		__cpu_name[cpu] = "MIPS 24KEc";
1069 		break;
1070 	case PRID_IMP_25KF:
1071 		c->cputype = CPU_25KF;
1072 		c->writecombine = _CACHE_UNCACHED;
1073 		__cpu_name[cpu] = "MIPS 25Kc";
1074 		break;
1075 	case PRID_IMP_34K:
1076 		c->cputype = CPU_34K;
1077 		c->writecombine = _CACHE_UNCACHED;
1078 		__cpu_name[cpu] = "MIPS 34Kc";
1079 		break;
1080 	case PRID_IMP_74K:
1081 		c->cputype = CPU_74K;
1082 		c->writecombine = _CACHE_UNCACHED;
1083 		__cpu_name[cpu] = "MIPS 74Kc";
1084 		break;
1085 	case PRID_IMP_M14KC:
1086 		c->cputype = CPU_M14KC;
1087 		c->writecombine = _CACHE_UNCACHED;
1088 		__cpu_name[cpu] = "MIPS M14Kc";
1089 		break;
1090 	case PRID_IMP_M14KEC:
1091 		c->cputype = CPU_M14KEC;
1092 		c->writecombine = _CACHE_UNCACHED;
1093 		__cpu_name[cpu] = "MIPS M14KEc";
1094 		break;
1095 	case PRID_IMP_1004K:
1096 		c->cputype = CPU_1004K;
1097 		c->writecombine = _CACHE_UNCACHED;
1098 		__cpu_name[cpu] = "MIPS 1004Kc";
1099 		break;
1100 	case PRID_IMP_1074K:
1101 		c->cputype = CPU_1074K;
1102 		c->writecombine = _CACHE_UNCACHED;
1103 		__cpu_name[cpu] = "MIPS 1074Kc";
1104 		break;
1105 	case PRID_IMP_INTERAPTIV_UP:
1106 		c->cputype = CPU_INTERAPTIV;
1107 		__cpu_name[cpu] = "MIPS interAptiv";
1108 		break;
1109 	case PRID_IMP_INTERAPTIV_MP:
1110 		c->cputype = CPU_INTERAPTIV;
1111 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1112 		break;
1113 	case PRID_IMP_PROAPTIV_UP:
1114 		c->cputype = CPU_PROAPTIV;
1115 		__cpu_name[cpu] = "MIPS proAptiv";
1116 		break;
1117 	case PRID_IMP_PROAPTIV_MP:
1118 		c->cputype = CPU_PROAPTIV;
1119 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1120 		break;
1121 	case PRID_IMP_P5600:
1122 		c->cputype = CPU_P5600;
1123 		__cpu_name[cpu] = "MIPS P5600";
1124 		break;
1125 	case PRID_IMP_M5150:
1126 		c->cputype = CPU_M5150;
1127 		__cpu_name[cpu] = "MIPS M5150";
1128 		break;
1129 	}
1130 
1131 	decode_configs(c);
1132 
1133 	spram_config();
1134 }
1135 
1136 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1137 {
1138 	decode_configs(c);
1139 	switch (c->processor_id & PRID_IMP_MASK) {
1140 	case PRID_IMP_AU1_REV1:
1141 	case PRID_IMP_AU1_REV2:
1142 		c->cputype = CPU_ALCHEMY;
1143 		switch ((c->processor_id >> 24) & 0xff) {
1144 		case 0:
1145 			__cpu_name[cpu] = "Au1000";
1146 			break;
1147 		case 1:
1148 			__cpu_name[cpu] = "Au1500";
1149 			break;
1150 		case 2:
1151 			__cpu_name[cpu] = "Au1100";
1152 			break;
1153 		case 3:
1154 			__cpu_name[cpu] = "Au1550";
1155 			break;
1156 		case 4:
1157 			__cpu_name[cpu] = "Au1200";
1158 			if ((c->processor_id & PRID_REV_MASK) == 2)
1159 				__cpu_name[cpu] = "Au1250";
1160 			break;
1161 		case 5:
1162 			__cpu_name[cpu] = "Au1210";
1163 			break;
1164 		default:
1165 			__cpu_name[cpu] = "Au1xxx";
1166 			break;
1167 		}
1168 		break;
1169 	}
1170 }
1171 
1172 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1173 {
1174 	decode_configs(c);
1175 
1176 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1177 	switch (c->processor_id & PRID_IMP_MASK) {
1178 	case PRID_IMP_SB1:
1179 		c->cputype = CPU_SB1;
1180 		__cpu_name[cpu] = "SiByte SB1";
1181 		/* FPU in pass1 is known to have issues. */
1182 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1183 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1184 		break;
1185 	case PRID_IMP_SB1A:
1186 		c->cputype = CPU_SB1A;
1187 		__cpu_name[cpu] = "SiByte SB1A";
1188 		break;
1189 	}
1190 }
1191 
1192 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1193 {
1194 	decode_configs(c);
1195 	switch (c->processor_id & PRID_IMP_MASK) {
1196 	case PRID_IMP_SR71000:
1197 		c->cputype = CPU_SR71000;
1198 		__cpu_name[cpu] = "Sandcraft SR71000";
1199 		c->scache.ways = 8;
1200 		c->tlbsize = 64;
1201 		break;
1202 	}
1203 }
1204 
1205 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1206 {
1207 	decode_configs(c);
1208 	switch (c->processor_id & PRID_IMP_MASK) {
1209 	case PRID_IMP_PR4450:
1210 		c->cputype = CPU_PR4450;
1211 		__cpu_name[cpu] = "Philips PR4450";
1212 		set_isa(c, MIPS_CPU_ISA_M32R1);
1213 		break;
1214 	}
1215 }
1216 
1217 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1218 {
1219 	decode_configs(c);
1220 	switch (c->processor_id & PRID_IMP_MASK) {
1221 	case PRID_IMP_BMIPS32_REV4:
1222 	case PRID_IMP_BMIPS32_REV8:
1223 		c->cputype = CPU_BMIPS32;
1224 		__cpu_name[cpu] = "Broadcom BMIPS32";
1225 		set_elf_platform(cpu, "bmips32");
1226 		break;
1227 	case PRID_IMP_BMIPS3300:
1228 	case PRID_IMP_BMIPS3300_ALT:
1229 	case PRID_IMP_BMIPS3300_BUG:
1230 		c->cputype = CPU_BMIPS3300;
1231 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1232 		set_elf_platform(cpu, "bmips3300");
1233 		break;
1234 	case PRID_IMP_BMIPS43XX: {
1235 		int rev = c->processor_id & PRID_REV_MASK;
1236 
1237 		if (rev >= PRID_REV_BMIPS4380_LO &&
1238 				rev <= PRID_REV_BMIPS4380_HI) {
1239 			c->cputype = CPU_BMIPS4380;
1240 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1241 			set_elf_platform(cpu, "bmips4380");
1242 		} else {
1243 			c->cputype = CPU_BMIPS4350;
1244 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1245 			set_elf_platform(cpu, "bmips4350");
1246 		}
1247 		break;
1248 	}
1249 	case PRID_IMP_BMIPS5000:
1250 	case PRID_IMP_BMIPS5200:
1251 		c->cputype = CPU_BMIPS5000;
1252 		__cpu_name[cpu] = "Broadcom BMIPS5000";
1253 		set_elf_platform(cpu, "bmips5000");
1254 		c->options |= MIPS_CPU_ULRI;
1255 		break;
1256 	}
1257 }
1258 
1259 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1260 {
1261 	decode_configs(c);
1262 	switch (c->processor_id & PRID_IMP_MASK) {
1263 	case PRID_IMP_CAVIUM_CN38XX:
1264 	case PRID_IMP_CAVIUM_CN31XX:
1265 	case PRID_IMP_CAVIUM_CN30XX:
1266 		c->cputype = CPU_CAVIUM_OCTEON;
1267 		__cpu_name[cpu] = "Cavium Octeon";
1268 		goto platform;
1269 	case PRID_IMP_CAVIUM_CN58XX:
1270 	case PRID_IMP_CAVIUM_CN56XX:
1271 	case PRID_IMP_CAVIUM_CN50XX:
1272 	case PRID_IMP_CAVIUM_CN52XX:
1273 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1274 		__cpu_name[cpu] = "Cavium Octeon+";
1275 platform:
1276 		set_elf_platform(cpu, "octeon");
1277 		break;
1278 	case PRID_IMP_CAVIUM_CN61XX:
1279 	case PRID_IMP_CAVIUM_CN63XX:
1280 	case PRID_IMP_CAVIUM_CN66XX:
1281 	case PRID_IMP_CAVIUM_CN68XX:
1282 	case PRID_IMP_CAVIUM_CNF71XX:
1283 		c->cputype = CPU_CAVIUM_OCTEON2;
1284 		__cpu_name[cpu] = "Cavium Octeon II";
1285 		set_elf_platform(cpu, "octeon2");
1286 		break;
1287 	case PRID_IMP_CAVIUM_CN70XX:
1288 	case PRID_IMP_CAVIUM_CN78XX:
1289 		c->cputype = CPU_CAVIUM_OCTEON3;
1290 		__cpu_name[cpu] = "Cavium Octeon III";
1291 		set_elf_platform(cpu, "octeon3");
1292 		break;
1293 	default:
1294 		printk(KERN_INFO "Unknown Octeon chip!\n");
1295 		c->cputype = CPU_UNKNOWN;
1296 		break;
1297 	}
1298 }
1299 
1300 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1301 {
1302 	decode_configs(c);
1303 	/* JZRISC does not implement the CP0 counter. */
1304 	c->options &= ~MIPS_CPU_COUNTER;
1305 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
1306 	switch (c->processor_id & PRID_IMP_MASK) {
1307 	case PRID_IMP_JZRISC:
1308 		c->cputype = CPU_JZRISC;
1309 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1310 		__cpu_name[cpu] = "Ingenic JZRISC";
1311 		break;
1312 	default:
1313 		panic("Unknown Ingenic Processor ID!");
1314 		break;
1315 	}
1316 }
1317 
1318 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1319 {
1320 	decode_configs(c);
1321 
1322 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1323 		c->cputype = CPU_ALCHEMY;
1324 		__cpu_name[cpu] = "Au1300";
1325 		/* following stuff is not for Alchemy */
1326 		return;
1327 	}
1328 
1329 	c->options = (MIPS_CPU_TLB	 |
1330 			MIPS_CPU_4KEX	 |
1331 			MIPS_CPU_COUNTER |
1332 			MIPS_CPU_DIVEC	 |
1333 			MIPS_CPU_WATCH	 |
1334 			MIPS_CPU_EJTAG	 |
1335 			MIPS_CPU_LLSC);
1336 
1337 	switch (c->processor_id & PRID_IMP_MASK) {
1338 	case PRID_IMP_NETLOGIC_XLP2XX:
1339 	case PRID_IMP_NETLOGIC_XLP9XX:
1340 	case PRID_IMP_NETLOGIC_XLP5XX:
1341 		c->cputype = CPU_XLP;
1342 		__cpu_name[cpu] = "Broadcom XLPII";
1343 		break;
1344 
1345 	case PRID_IMP_NETLOGIC_XLP8XX:
1346 	case PRID_IMP_NETLOGIC_XLP3XX:
1347 		c->cputype = CPU_XLP;
1348 		__cpu_name[cpu] = "Netlogic XLP";
1349 		break;
1350 
1351 	case PRID_IMP_NETLOGIC_XLR732:
1352 	case PRID_IMP_NETLOGIC_XLR716:
1353 	case PRID_IMP_NETLOGIC_XLR532:
1354 	case PRID_IMP_NETLOGIC_XLR308:
1355 	case PRID_IMP_NETLOGIC_XLR532C:
1356 	case PRID_IMP_NETLOGIC_XLR516C:
1357 	case PRID_IMP_NETLOGIC_XLR508C:
1358 	case PRID_IMP_NETLOGIC_XLR308C:
1359 		c->cputype = CPU_XLR;
1360 		__cpu_name[cpu] = "Netlogic XLR";
1361 		break;
1362 
1363 	case PRID_IMP_NETLOGIC_XLS608:
1364 	case PRID_IMP_NETLOGIC_XLS408:
1365 	case PRID_IMP_NETLOGIC_XLS404:
1366 	case PRID_IMP_NETLOGIC_XLS208:
1367 	case PRID_IMP_NETLOGIC_XLS204:
1368 	case PRID_IMP_NETLOGIC_XLS108:
1369 	case PRID_IMP_NETLOGIC_XLS104:
1370 	case PRID_IMP_NETLOGIC_XLS616B:
1371 	case PRID_IMP_NETLOGIC_XLS608B:
1372 	case PRID_IMP_NETLOGIC_XLS416B:
1373 	case PRID_IMP_NETLOGIC_XLS412B:
1374 	case PRID_IMP_NETLOGIC_XLS408B:
1375 	case PRID_IMP_NETLOGIC_XLS404B:
1376 		c->cputype = CPU_XLR;
1377 		__cpu_name[cpu] = "Netlogic XLS";
1378 		break;
1379 
1380 	default:
1381 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1382 		       c->processor_id);
1383 		c->cputype = CPU_XLR;
1384 		break;
1385 	}
1386 
1387 	if (c->cputype == CPU_XLP) {
1388 		set_isa(c, MIPS_CPU_ISA_M64R2);
1389 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1390 		/* This will be updated again after all threads are woken up */
1391 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1392 	} else {
1393 		set_isa(c, MIPS_CPU_ISA_M64R1);
1394 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1395 	}
1396 	c->kscratch_mask = 0xf;
1397 }
1398 
1399 #ifdef CONFIG_64BIT
1400 /* For use by uaccess.h */
1401 u64 __ua_limit;
1402 EXPORT_SYMBOL(__ua_limit);
1403 #endif
1404 
1405 const char *__cpu_name[NR_CPUS];
1406 const char *__elf_platform;
1407 
1408 void cpu_probe(void)
1409 {
1410 	struct cpuinfo_mips *c = &current_cpu_data;
1411 	unsigned int cpu = smp_processor_id();
1412 
1413 	c->processor_id = PRID_IMP_UNKNOWN;
1414 	c->fpu_id	= FPIR_IMP_NONE;
1415 	c->cputype	= CPU_UNKNOWN;
1416 	c->writecombine = _CACHE_UNCACHED;
1417 
1418 	c->fpu_csr31	= FPU_CSR_RN;
1419 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
1420 
1421 	c->processor_id = read_c0_prid();
1422 	switch (c->processor_id & PRID_COMP_MASK) {
1423 	case PRID_COMP_LEGACY:
1424 		cpu_probe_legacy(c, cpu);
1425 		break;
1426 	case PRID_COMP_MIPS:
1427 		cpu_probe_mips(c, cpu);
1428 		break;
1429 	case PRID_COMP_ALCHEMY:
1430 		cpu_probe_alchemy(c, cpu);
1431 		break;
1432 	case PRID_COMP_SIBYTE:
1433 		cpu_probe_sibyte(c, cpu);
1434 		break;
1435 	case PRID_COMP_BROADCOM:
1436 		cpu_probe_broadcom(c, cpu);
1437 		break;
1438 	case PRID_COMP_SANDCRAFT:
1439 		cpu_probe_sandcraft(c, cpu);
1440 		break;
1441 	case PRID_COMP_NXP:
1442 		cpu_probe_nxp(c, cpu);
1443 		break;
1444 	case PRID_COMP_CAVIUM:
1445 		cpu_probe_cavium(c, cpu);
1446 		break;
1447 	case PRID_COMP_INGENIC:
1448 		cpu_probe_ingenic(c, cpu);
1449 		break;
1450 	case PRID_COMP_NETLOGIC:
1451 		cpu_probe_netlogic(c, cpu);
1452 		break;
1453 	}
1454 
1455 	BUG_ON(!__cpu_name[cpu]);
1456 	BUG_ON(c->cputype == CPU_UNKNOWN);
1457 
1458 	/*
1459 	 * Platform code can force the cpu type to optimize code
1460 	 * generation. In that case be sure the cpu type is correctly
1461 	 * manually setup otherwise it could trigger some nasty bugs.
1462 	 */
1463 	BUG_ON(current_cpu_type() != c->cputype);
1464 
1465 	if (mips_fpu_disabled)
1466 		c->options &= ~MIPS_CPU_FPU;
1467 
1468 	if (mips_dsp_disabled)
1469 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
1470 
1471 	if (mips_htw_disabled) {
1472 		c->options &= ~MIPS_CPU_HTW;
1473 		write_c0_pwctl(read_c0_pwctl() &
1474 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
1475 	}
1476 
1477 	if (c->options & MIPS_CPU_FPU)
1478 		cpu_set_fpu_opts(c);
1479 	else
1480 		cpu_set_nofpu_opts(c);
1481 
1482 	if (cpu_has_mips_r2_r6) {
1483 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
1484 		/* R2 has Performance Counter Interrupt indicator */
1485 		c->options |= MIPS_CPU_PCI;
1486 	}
1487 	else
1488 		c->srsets = 1;
1489 
1490 	if (cpu_has_msa) {
1491 		c->msa_id = cpu_get_msa_id();
1492 		WARN(c->msa_id & MSA_IR_WRPF,
1493 		     "Vector register partitioning unimplemented!");
1494 	}
1495 
1496 	cpu_probe_vmbits(c);
1497 
1498 #ifdef CONFIG_64BIT
1499 	if (cpu == 0)
1500 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
1501 #endif
1502 }
1503 
1504 void cpu_report(void)
1505 {
1506 	struct cpuinfo_mips *c = &current_cpu_data;
1507 
1508 	pr_info("CPU%d revision is: %08x (%s)\n",
1509 		smp_processor_id(), c->processor_id, cpu_name_string());
1510 	if (c->options & MIPS_CPU_FPU)
1511 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
1512 	if (cpu_has_msa)
1513 		pr_info("MSA revision is: %08x\n", c->msa_id);
1514 }
1515