xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 6c9111bc)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Processor capabilities determination functions.
4  *
5  * Copyright (C) xxxx  the Anonymous
6  * Copyright (C) 1994 - 2006 Ralf Baechle
7  * Copyright (C) 2003, 2004  Maciej W. Rozycki
8  * Copyright (C) 2001, 2004, 2011, 2012	 MIPS Technologies, Inc.
9  */
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/ptrace.h>
13 #include <linux/smp.h>
14 #include <linux/stddef.h>
15 #include <linux/export.h>
16 
17 #include <asm/bugs.h>
18 #include <asm/cpu.h>
19 #include <asm/cpu-features.h>
20 #include <asm/cpu-type.h>
21 #include <asm/fpu.h>
22 #include <asm/mipsregs.h>
23 #include <asm/mipsmtregs.h>
24 #include <asm/msa.h>
25 #include <asm/watch.h>
26 #include <asm/elf.h>
27 #include <asm/pgtable-bits.h>
28 #include <asm/spram.h>
29 #include <linux/uaccess.h>
30 
31 #include "fpu-probe.h"
32 
33 #include <asm/mach-loongson64/cpucfg-emul.h>
34 
35 /* Hardware capabilities */
36 unsigned int elf_hwcap __read_mostly;
37 EXPORT_SYMBOL_GPL(elf_hwcap);
38 
39 static inline unsigned long cpu_get_msa_id(void)
40 {
41 	unsigned long status, msa_id;
42 
43 	status = read_c0_status();
44 	__enable_fpu(FPU_64BIT);
45 	enable_msa();
46 	msa_id = read_msa_ir();
47 	disable_msa();
48 	write_c0_status(status);
49 	return msa_id;
50 }
51 
52 static int mips_dsp_disabled;
53 
54 static int __init dsp_disable(char *s)
55 {
56 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
57 	mips_dsp_disabled = 1;
58 
59 	return 1;
60 }
61 
62 __setup("nodsp", dsp_disable);
63 
64 static int mips_htw_disabled;
65 
66 static int __init htw_disable(char *s)
67 {
68 	mips_htw_disabled = 1;
69 	cpu_data[0].options &= ~MIPS_CPU_HTW;
70 	write_c0_pwctl(read_c0_pwctl() &
71 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
72 
73 	return 1;
74 }
75 
76 __setup("nohtw", htw_disable);
77 
78 static int mips_ftlb_disabled;
79 static int mips_has_ftlb_configured;
80 
81 enum ftlb_flags {
82 	FTLB_EN		= 1 << 0,
83 	FTLB_SET_PROB	= 1 << 1,
84 };
85 
86 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
87 
88 static int __init ftlb_disable(char *s)
89 {
90 	unsigned int config4, mmuextdef;
91 
92 	/*
93 	 * If the core hasn't done any FTLB configuration, there is nothing
94 	 * for us to do here.
95 	 */
96 	if (!mips_has_ftlb_configured)
97 		return 1;
98 
99 	/* Disable it in the boot cpu */
100 	if (set_ftlb_enable(&cpu_data[0], 0)) {
101 		pr_warn("Can't turn FTLB off\n");
102 		return 1;
103 	}
104 
105 	config4 = read_c0_config4();
106 
107 	/* Check that FTLB has been disabled */
108 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
109 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
110 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
111 		/* This should never happen */
112 		pr_warn("FTLB could not be disabled!\n");
113 		return 1;
114 	}
115 
116 	mips_ftlb_disabled = 1;
117 	mips_has_ftlb_configured = 0;
118 
119 	/*
120 	 * noftlb is mainly used for debug purposes so print
121 	 * an informative message instead of using pr_debug()
122 	 */
123 	pr_info("FTLB has been disabled\n");
124 
125 	/*
126 	 * Some of these bits are duplicated in the decode_config4.
127 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
128 	 * once FTLB has been disabled so undo what decode_config4 did.
129 	 */
130 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
131 			       cpu_data[0].tlbsizeftlbsets;
132 	cpu_data[0].tlbsizeftlbsets = 0;
133 	cpu_data[0].tlbsizeftlbways = 0;
134 
135 	return 1;
136 }
137 
138 __setup("noftlb", ftlb_disable);
139 
140 /*
141  * Check if the CPU has per tc perf counters
142  */
143 static inline void cpu_set_mt_per_tc_perf(struct cpuinfo_mips *c)
144 {
145 	if (read_c0_config7() & MTI_CONF7_PTC)
146 		c->options |= MIPS_CPU_MT_PER_TC_PERF_COUNTERS;
147 }
148 
149 static inline void check_errata(void)
150 {
151 	struct cpuinfo_mips *c = &current_cpu_data;
152 
153 	switch (current_cpu_type()) {
154 	case CPU_34K:
155 		/*
156 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
157 		 * This code only handles VPE0, any SMP/RTOS code
158 		 * making use of VPE1 will be responsable for that VPE.
159 		 */
160 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
161 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
162 		break;
163 	default:
164 		break;
165 	}
166 }
167 
168 void __init check_bugs32(void)
169 {
170 	check_errata();
171 }
172 
173 /*
174  * Probe whether cpu has config register by trying to play with
175  * alternate cache bit and see whether it matters.
176  * It's used by cpu_probe to distinguish between R3000A and R3081.
177  */
178 static inline int cpu_has_confreg(void)
179 {
180 #ifdef CONFIG_CPU_R3000
181 	extern unsigned long r3k_cache_size(unsigned long);
182 	unsigned long size1, size2;
183 	unsigned long cfg = read_c0_conf();
184 
185 	size1 = r3k_cache_size(ST0_ISC);
186 	write_c0_conf(cfg ^ R30XX_CONF_AC);
187 	size2 = r3k_cache_size(ST0_ISC);
188 	write_c0_conf(cfg);
189 	return size1 != size2;
190 #else
191 	return 0;
192 #endif
193 }
194 
195 static inline void set_elf_platform(int cpu, const char *plat)
196 {
197 	if (cpu == 0)
198 		__elf_platform = plat;
199 }
200 
201 static inline void set_elf_base_platform(const char *plat)
202 {
203 	if (__elf_base_platform == NULL) {
204 		__elf_base_platform = plat;
205 	}
206 }
207 
208 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
209 {
210 #ifdef __NEED_VMBITS_PROBE
211 	write_c0_entryhi(0x3fffffffffffe000ULL);
212 	back_to_back_c0_hazard();
213 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
214 #endif
215 }
216 
217 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
218 {
219 	switch (isa) {
220 	case MIPS_CPU_ISA_M64R5:
221 		c->isa_level |= MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5;
222 		set_elf_base_platform("mips64r5");
223 		fallthrough;
224 	case MIPS_CPU_ISA_M64R2:
225 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
226 		set_elf_base_platform("mips64r2");
227 		fallthrough;
228 	case MIPS_CPU_ISA_M64R1:
229 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
230 		set_elf_base_platform("mips64");
231 		fallthrough;
232 	case MIPS_CPU_ISA_V:
233 		c->isa_level |= MIPS_CPU_ISA_V;
234 		set_elf_base_platform("mips5");
235 		fallthrough;
236 	case MIPS_CPU_ISA_IV:
237 		c->isa_level |= MIPS_CPU_ISA_IV;
238 		set_elf_base_platform("mips4");
239 		fallthrough;
240 	case MIPS_CPU_ISA_III:
241 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
242 		set_elf_base_platform("mips3");
243 		break;
244 
245 	/* R6 incompatible with everything else */
246 	case MIPS_CPU_ISA_M64R6:
247 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
248 		set_elf_base_platform("mips64r6");
249 		fallthrough;
250 	case MIPS_CPU_ISA_M32R6:
251 		c->isa_level |= MIPS_CPU_ISA_M32R6;
252 		set_elf_base_platform("mips32r6");
253 		/* Break here so we don't add incompatible ISAs */
254 		break;
255 	case MIPS_CPU_ISA_M32R5:
256 		c->isa_level |= MIPS_CPU_ISA_M32R5;
257 		set_elf_base_platform("mips32r5");
258 		fallthrough;
259 	case MIPS_CPU_ISA_M32R2:
260 		c->isa_level |= MIPS_CPU_ISA_M32R2;
261 		set_elf_base_platform("mips32r2");
262 		fallthrough;
263 	case MIPS_CPU_ISA_M32R1:
264 		c->isa_level |= MIPS_CPU_ISA_M32R1;
265 		set_elf_base_platform("mips32");
266 		fallthrough;
267 	case MIPS_CPU_ISA_II:
268 		c->isa_level |= MIPS_CPU_ISA_II;
269 		set_elf_base_platform("mips2");
270 		break;
271 	}
272 }
273 
274 static char unknown_isa[] = KERN_ERR \
275 	"Unsupported ISA type, c0.config0: %d.";
276 
277 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
278 {
279 
280 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
281 
282 	/*
283 	 * 0 = All TLBWR instructions go to FTLB
284 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
285 	 * FTLB and 1 goes to the VTLB.
286 	 * 2 = 7:1: As above with 7:1 ratio.
287 	 * 3 = 3:1: As above with 3:1 ratio.
288 	 *
289 	 * Use the linear midpoint as the probability threshold.
290 	 */
291 	if (probability >= 12)
292 		return 1;
293 	else if (probability >= 6)
294 		return 2;
295 	else
296 		/*
297 		 * So FTLB is less than 4 times bigger than VTLB.
298 		 * A 3:1 ratio can still be useful though.
299 		 */
300 		return 3;
301 }
302 
303 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
304 {
305 	unsigned int config;
306 
307 	/* It's implementation dependent how the FTLB can be enabled */
308 	switch (c->cputype) {
309 	case CPU_PROAPTIV:
310 	case CPU_P5600:
311 	case CPU_P6600:
312 		/* proAptiv & related cores use Config6 to enable the FTLB */
313 		config = read_c0_config6();
314 
315 		if (flags & FTLB_EN)
316 			config |= MTI_CONF6_FTLBEN;
317 		else
318 			config &= ~MTI_CONF6_FTLBEN;
319 
320 		if (flags & FTLB_SET_PROB) {
321 			config &= ~(3 << MTI_CONF6_FTLBP_SHIFT);
322 			config |= calculate_ftlb_probability(c)
323 				  << MTI_CONF6_FTLBP_SHIFT;
324 		}
325 
326 		write_c0_config6(config);
327 		back_to_back_c0_hazard();
328 		break;
329 	case CPU_I6400:
330 	case CPU_I6500:
331 		/* There's no way to disable the FTLB */
332 		if (!(flags & FTLB_EN))
333 			return 1;
334 		return 0;
335 	case CPU_LOONGSON64:
336 		/* Flush ITLB, DTLB, VTLB and FTLB */
337 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
338 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
339 		/* Loongson-3 cores use Config6 to enable the FTLB */
340 		config = read_c0_config6();
341 		if (flags & FTLB_EN)
342 			/* Enable FTLB */
343 			write_c0_config6(config & ~LOONGSON_CONF6_FTLBDIS);
344 		else
345 			/* Disable FTLB */
346 			write_c0_config6(config | LOONGSON_CONF6_FTLBDIS);
347 		break;
348 	default:
349 		return 1;
350 	}
351 
352 	return 0;
353 }
354 
355 static int mm_config(struct cpuinfo_mips *c)
356 {
357 	unsigned int config0, update, mm;
358 
359 	config0 = read_c0_config();
360 	mm = config0 & MIPS_CONF_MM;
361 
362 	/*
363 	 * It's implementation dependent what type of write-merge is supported
364 	 * and whether it can be enabled/disabled. If it is settable lets make
365 	 * the merging allowed by default. Some platforms might have
366 	 * write-through caching unsupported. In this case just ignore the
367 	 * CP0.Config.MM bit field value.
368 	 */
369 	switch (c->cputype) {
370 	case CPU_24K:
371 	case CPU_34K:
372 	case CPU_74K:
373 	case CPU_P5600:
374 	case CPU_P6600:
375 		c->options |= MIPS_CPU_MM_FULL;
376 		update = MIPS_CONF_MM_FULL;
377 		break;
378 	case CPU_1004K:
379 	case CPU_1074K:
380 	case CPU_INTERAPTIV:
381 	case CPU_PROAPTIV:
382 		mm = 0;
383 		fallthrough;
384 	default:
385 		update = 0;
386 		break;
387 	}
388 
389 	if (update) {
390 		config0 = (config0 & ~MIPS_CONF_MM) | update;
391 		write_c0_config(config0);
392 	} else if (mm == MIPS_CONF_MM_SYSAD) {
393 		c->options |= MIPS_CPU_MM_SYSAD;
394 	} else if (mm == MIPS_CONF_MM_FULL) {
395 		c->options |= MIPS_CPU_MM_FULL;
396 	}
397 
398 	return 0;
399 }
400 
401 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
402 {
403 	unsigned int config0;
404 	int isa, mt;
405 
406 	config0 = read_c0_config();
407 
408 	/*
409 	 * Look for Standard TLB or Dual VTLB and FTLB
410 	 */
411 	mt = config0 & MIPS_CONF_MT;
412 	if (mt == MIPS_CONF_MT_TLB)
413 		c->options |= MIPS_CPU_TLB;
414 	else if (mt == MIPS_CONF_MT_FTLB)
415 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
416 
417 	isa = (config0 & MIPS_CONF_AT) >> 13;
418 	switch (isa) {
419 	case 0:
420 		switch ((config0 & MIPS_CONF_AR) >> 10) {
421 		case 0:
422 			set_isa(c, MIPS_CPU_ISA_M32R1);
423 			break;
424 		case 1:
425 			set_isa(c, MIPS_CPU_ISA_M32R2);
426 			break;
427 		case 2:
428 			set_isa(c, MIPS_CPU_ISA_M32R6);
429 			break;
430 		default:
431 			goto unknown;
432 		}
433 		break;
434 	case 2:
435 		switch ((config0 & MIPS_CONF_AR) >> 10) {
436 		case 0:
437 			set_isa(c, MIPS_CPU_ISA_M64R1);
438 			break;
439 		case 1:
440 			set_isa(c, MIPS_CPU_ISA_M64R2);
441 			break;
442 		case 2:
443 			set_isa(c, MIPS_CPU_ISA_M64R6);
444 			break;
445 		default:
446 			goto unknown;
447 		}
448 		break;
449 	default:
450 		goto unknown;
451 	}
452 
453 	return config0 & MIPS_CONF_M;
454 
455 unknown:
456 	panic(unknown_isa, config0);
457 }
458 
459 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
460 {
461 	unsigned int config1;
462 
463 	config1 = read_c0_config1();
464 
465 	if (config1 & MIPS_CONF1_MD)
466 		c->ases |= MIPS_ASE_MDMX;
467 	if (config1 & MIPS_CONF1_PC)
468 		c->options |= MIPS_CPU_PERF;
469 	if (config1 & MIPS_CONF1_WR)
470 		c->options |= MIPS_CPU_WATCH;
471 	if (config1 & MIPS_CONF1_CA)
472 		c->ases |= MIPS_ASE_MIPS16;
473 	if (config1 & MIPS_CONF1_EP)
474 		c->options |= MIPS_CPU_EJTAG;
475 	if (config1 & MIPS_CONF1_FP) {
476 		c->options |= MIPS_CPU_FPU;
477 		c->options |= MIPS_CPU_32FPR;
478 	}
479 	if (cpu_has_tlb) {
480 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
481 		c->tlbsizevtlb = c->tlbsize;
482 		c->tlbsizeftlbsets = 0;
483 	}
484 
485 	return config1 & MIPS_CONF_M;
486 }
487 
488 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
489 {
490 	unsigned int config2;
491 
492 	config2 = read_c0_config2();
493 
494 	if (config2 & MIPS_CONF2_SL)
495 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
496 
497 	return config2 & MIPS_CONF_M;
498 }
499 
500 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
501 {
502 	unsigned int config3;
503 
504 	config3 = read_c0_config3();
505 
506 	if (config3 & MIPS_CONF3_SM) {
507 		c->ases |= MIPS_ASE_SMARTMIPS;
508 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
509 	}
510 	if (config3 & MIPS_CONF3_RXI)
511 		c->options |= MIPS_CPU_RIXI;
512 	if (config3 & MIPS_CONF3_CTXTC)
513 		c->options |= MIPS_CPU_CTXTC;
514 	if (config3 & MIPS_CONF3_DSP)
515 		c->ases |= MIPS_ASE_DSP;
516 	if (config3 & MIPS_CONF3_DSP2P) {
517 		c->ases |= MIPS_ASE_DSP2P;
518 		if (cpu_has_mips_r6)
519 			c->ases |= MIPS_ASE_DSP3;
520 	}
521 	if (config3 & MIPS_CONF3_VINT)
522 		c->options |= MIPS_CPU_VINT;
523 	if (config3 & MIPS_CONF3_VEIC)
524 		c->options |= MIPS_CPU_VEIC;
525 	if (config3 & MIPS_CONF3_LPA)
526 		c->options |= MIPS_CPU_LPA;
527 	if (config3 & MIPS_CONF3_MT)
528 		c->ases |= MIPS_ASE_MIPSMT;
529 	if (config3 & MIPS_CONF3_ULRI)
530 		c->options |= MIPS_CPU_ULRI;
531 	if (config3 & MIPS_CONF3_ISA)
532 		c->options |= MIPS_CPU_MICROMIPS;
533 	if (config3 & MIPS_CONF3_VZ)
534 		c->ases |= MIPS_ASE_VZ;
535 	if (config3 & MIPS_CONF3_SC)
536 		c->options |= MIPS_CPU_SEGMENTS;
537 	if (config3 & MIPS_CONF3_BI)
538 		c->options |= MIPS_CPU_BADINSTR;
539 	if (config3 & MIPS_CONF3_BP)
540 		c->options |= MIPS_CPU_BADINSTRP;
541 	if (config3 & MIPS_CONF3_MSA)
542 		c->ases |= MIPS_ASE_MSA;
543 	if (config3 & MIPS_CONF3_PW) {
544 		c->htw_seq = 0;
545 		c->options |= MIPS_CPU_HTW;
546 	}
547 	if (config3 & MIPS_CONF3_CDMM)
548 		c->options |= MIPS_CPU_CDMM;
549 	if (config3 & MIPS_CONF3_SP)
550 		c->options |= MIPS_CPU_SP;
551 
552 	return config3 & MIPS_CONF_M;
553 }
554 
555 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
556 {
557 	unsigned int config4;
558 	unsigned int newcf4;
559 	unsigned int mmuextdef;
560 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
561 	unsigned long asid_mask;
562 
563 	config4 = read_c0_config4();
564 
565 	if (cpu_has_tlb) {
566 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
567 			c->options |= MIPS_CPU_TLBINV;
568 
569 		/*
570 		 * R6 has dropped the MMUExtDef field from config4.
571 		 * On R6 the fields always describe the FTLB, and only if it is
572 		 * present according to Config.MT.
573 		 */
574 		if (!cpu_has_mips_r6)
575 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
576 		else if (cpu_has_ftlb)
577 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
578 		else
579 			mmuextdef = 0;
580 
581 		switch (mmuextdef) {
582 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
583 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
584 			c->tlbsizevtlb = c->tlbsize;
585 			break;
586 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
587 			c->tlbsizevtlb +=
588 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
589 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
590 			c->tlbsize = c->tlbsizevtlb;
591 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
592 			fallthrough;
593 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
594 			if (mips_ftlb_disabled)
595 				break;
596 			newcf4 = (config4 & ~ftlb_page) |
597 				(page_size_ftlb(mmuextdef) <<
598 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
599 			write_c0_config4(newcf4);
600 			back_to_back_c0_hazard();
601 			config4 = read_c0_config4();
602 			if (config4 != newcf4) {
603 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
604 				       PAGE_SIZE, config4);
605 				/* Switch FTLB off */
606 				set_ftlb_enable(c, 0);
607 				mips_ftlb_disabled = 1;
608 				break;
609 			}
610 			c->tlbsizeftlbsets = 1 <<
611 				((config4 & MIPS_CONF4_FTLBSETS) >>
612 				 MIPS_CONF4_FTLBSETS_SHIFT);
613 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
614 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
615 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
616 			mips_has_ftlb_configured = 1;
617 			break;
618 		}
619 	}
620 
621 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
622 				>> MIPS_CONF4_KSCREXIST_SHIFT;
623 
624 	asid_mask = MIPS_ENTRYHI_ASID;
625 	if (config4 & MIPS_CONF4_AE)
626 		asid_mask |= MIPS_ENTRYHI_ASIDX;
627 	set_cpu_asid_mask(c, asid_mask);
628 
629 	/*
630 	 * Warn if the computed ASID mask doesn't match the mask the kernel
631 	 * is built for. This may indicate either a serious problem or an
632 	 * easy optimisation opportunity, but either way should be addressed.
633 	 */
634 	WARN_ON(asid_mask != cpu_asid_mask(c));
635 
636 	return config4 & MIPS_CONF_M;
637 }
638 
639 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
640 {
641 	unsigned int config5, max_mmid_width;
642 	unsigned long asid_mask;
643 
644 	config5 = read_c0_config5();
645 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
646 
647 	if (cpu_has_mips_r6) {
648 		if (!__builtin_constant_p(cpu_has_mmid) || cpu_has_mmid)
649 			config5 |= MIPS_CONF5_MI;
650 		else
651 			config5 &= ~MIPS_CONF5_MI;
652 	}
653 
654 	write_c0_config5(config5);
655 
656 	if (config5 & MIPS_CONF5_EVA)
657 		c->options |= MIPS_CPU_EVA;
658 	if (config5 & MIPS_CONF5_MRP)
659 		c->options |= MIPS_CPU_MAAR;
660 	if (config5 & MIPS_CONF5_LLB)
661 		c->options |= MIPS_CPU_RW_LLB;
662 	if (config5 & MIPS_CONF5_MVH)
663 		c->options |= MIPS_CPU_MVH;
664 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
665 		c->options |= MIPS_CPU_VP;
666 	if (config5 & MIPS_CONF5_CA2)
667 		c->ases |= MIPS_ASE_MIPS16E2;
668 
669 	if (config5 & MIPS_CONF5_CRCP)
670 		elf_hwcap |= HWCAP_MIPS_CRC32;
671 
672 	if (cpu_has_mips_r6) {
673 		/* Ensure the write to config5 above takes effect */
674 		back_to_back_c0_hazard();
675 
676 		/* Check whether we successfully enabled MMID support */
677 		config5 = read_c0_config5();
678 		if (config5 & MIPS_CONF5_MI)
679 			c->options |= MIPS_CPU_MMID;
680 
681 		/*
682 		 * Warn if we've hardcoded cpu_has_mmid to a value unsuitable
683 		 * for the CPU we're running on, or if CPUs in an SMP system
684 		 * have inconsistent MMID support.
685 		 */
686 		WARN_ON(!!cpu_has_mmid != !!(config5 & MIPS_CONF5_MI));
687 
688 		if (cpu_has_mmid) {
689 			write_c0_memorymapid(~0ul);
690 			back_to_back_c0_hazard();
691 			asid_mask = read_c0_memorymapid();
692 
693 			/*
694 			 * We maintain a bitmap to track MMID allocation, and
695 			 * need a sensible upper bound on the size of that
696 			 * bitmap. The initial CPU with MMID support (I6500)
697 			 * supports 16 bit MMIDs, which gives us an 8KiB
698 			 * bitmap. The architecture recommends that hardware
699 			 * support 32 bit MMIDs, which would give us a 512MiB
700 			 * bitmap - that's too big in most cases.
701 			 *
702 			 * Cap MMID width at 16 bits for now & we can revisit
703 			 * this if & when hardware supports anything wider.
704 			 */
705 			max_mmid_width = 16;
706 			if (asid_mask > GENMASK(max_mmid_width - 1, 0)) {
707 				pr_info("Capping MMID width at %d bits",
708 					max_mmid_width);
709 				asid_mask = GENMASK(max_mmid_width - 1, 0);
710 			}
711 
712 			set_cpu_asid_mask(c, asid_mask);
713 		}
714 	}
715 
716 	return config5 & MIPS_CONF_M;
717 }
718 
719 static void decode_configs(struct cpuinfo_mips *c)
720 {
721 	int ok;
722 
723 	/* MIPS32 or MIPS64 compliant CPU.  */
724 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
725 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
726 
727 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
728 
729 	/* Enable FTLB if present and not disabled */
730 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
731 
732 	ok = decode_config0(c);			/* Read Config registers.  */
733 	BUG_ON(!ok);				/* Arch spec violation!	 */
734 	if (ok)
735 		ok = decode_config1(c);
736 	if (ok)
737 		ok = decode_config2(c);
738 	if (ok)
739 		ok = decode_config3(c);
740 	if (ok)
741 		ok = decode_config4(c);
742 	if (ok)
743 		ok = decode_config5(c);
744 
745 	/* Probe the EBase.WG bit */
746 	if (cpu_has_mips_r2_r6) {
747 		u64 ebase;
748 		unsigned int status;
749 
750 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
751 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
752 					 : (s32)read_c0_ebase();
753 		if (ebase & MIPS_EBASE_WG) {
754 			/* WG bit already set, we can avoid the clumsy probe */
755 			c->options |= MIPS_CPU_EBASE_WG;
756 		} else {
757 			/* Its UNDEFINED to change EBase while BEV=0 */
758 			status = read_c0_status();
759 			write_c0_status(status | ST0_BEV);
760 			irq_enable_hazard();
761 			/*
762 			 * On pre-r6 cores, this may well clobber the upper bits
763 			 * of EBase. This is hard to avoid without potentially
764 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
765 			 */
766 			if (cpu_has_mips64r6)
767 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
768 			else
769 				write_c0_ebase(ebase | MIPS_EBASE_WG);
770 			back_to_back_c0_hazard();
771 			/* Restore BEV */
772 			write_c0_status(status);
773 			if (read_c0_ebase() & MIPS_EBASE_WG) {
774 				c->options |= MIPS_CPU_EBASE_WG;
775 				write_c0_ebase(ebase);
776 			}
777 		}
778 	}
779 
780 	/* configure the FTLB write probability */
781 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
782 
783 	mips_probe_watch_registers(c);
784 
785 #ifndef CONFIG_MIPS_CPS
786 	if (cpu_has_mips_r2_r6) {
787 		unsigned int core;
788 
789 		core = get_ebase_cpunum();
790 		if (cpu_has_mipsmt)
791 			core >>= fls(core_nvpes()) - 1;
792 		cpu_set_core(c, core);
793 	}
794 #endif
795 }
796 
797 /*
798  * Probe for certain guest capabilities by writing config bits and reading back.
799  * Finally write back the original value.
800  */
801 #define probe_gc0_config(name, maxconf, bits)				\
802 do {									\
803 	unsigned int tmp;						\
804 	tmp = read_gc0_##name();					\
805 	write_gc0_##name(tmp | (bits));					\
806 	back_to_back_c0_hazard();					\
807 	maxconf = read_gc0_##name();					\
808 	write_gc0_##name(tmp);						\
809 } while (0)
810 
811 /*
812  * Probe for dynamic guest capabilities by changing certain config bits and
813  * reading back to see if they change. Finally write back the original value.
814  */
815 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
816 do {									\
817 	maxconf = read_gc0_##name();					\
818 	write_gc0_##name(maxconf ^ (bits));				\
819 	back_to_back_c0_hazard();					\
820 	dynconf = maxconf ^ read_gc0_##name();				\
821 	write_gc0_##name(maxconf);					\
822 	maxconf |= dynconf;						\
823 } while (0)
824 
825 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
826 {
827 	unsigned int config0;
828 
829 	probe_gc0_config(config, config0, MIPS_CONF_M);
830 
831 	if (config0 & MIPS_CONF_M)
832 		c->guest.conf |= BIT(1);
833 	return config0 & MIPS_CONF_M;
834 }
835 
836 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
837 {
838 	unsigned int config1, config1_dyn;
839 
840 	probe_gc0_config_dyn(config1, config1, config1_dyn,
841 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
842 			     MIPS_CONF1_FP);
843 
844 	if (config1 & MIPS_CONF1_FP)
845 		c->guest.options |= MIPS_CPU_FPU;
846 	if (config1_dyn & MIPS_CONF1_FP)
847 		c->guest.options_dyn |= MIPS_CPU_FPU;
848 
849 	if (config1 & MIPS_CONF1_WR)
850 		c->guest.options |= MIPS_CPU_WATCH;
851 	if (config1_dyn & MIPS_CONF1_WR)
852 		c->guest.options_dyn |= MIPS_CPU_WATCH;
853 
854 	if (config1 & MIPS_CONF1_PC)
855 		c->guest.options |= MIPS_CPU_PERF;
856 	if (config1_dyn & MIPS_CONF1_PC)
857 		c->guest.options_dyn |= MIPS_CPU_PERF;
858 
859 	if (config1 & MIPS_CONF_M)
860 		c->guest.conf |= BIT(2);
861 	return config1 & MIPS_CONF_M;
862 }
863 
864 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
865 {
866 	unsigned int config2;
867 
868 	probe_gc0_config(config2, config2, MIPS_CONF_M);
869 
870 	if (config2 & MIPS_CONF_M)
871 		c->guest.conf |= BIT(3);
872 	return config2 & MIPS_CONF_M;
873 }
874 
875 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
876 {
877 	unsigned int config3, config3_dyn;
878 
879 	probe_gc0_config_dyn(config3, config3, config3_dyn,
880 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
881 			     MIPS_CONF3_CTXTC);
882 
883 	if (config3 & MIPS_CONF3_CTXTC)
884 		c->guest.options |= MIPS_CPU_CTXTC;
885 	if (config3_dyn & MIPS_CONF3_CTXTC)
886 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
887 
888 	if (config3 & MIPS_CONF3_PW)
889 		c->guest.options |= MIPS_CPU_HTW;
890 
891 	if (config3 & MIPS_CONF3_ULRI)
892 		c->guest.options |= MIPS_CPU_ULRI;
893 
894 	if (config3 & MIPS_CONF3_SC)
895 		c->guest.options |= MIPS_CPU_SEGMENTS;
896 
897 	if (config3 & MIPS_CONF3_BI)
898 		c->guest.options |= MIPS_CPU_BADINSTR;
899 	if (config3 & MIPS_CONF3_BP)
900 		c->guest.options |= MIPS_CPU_BADINSTRP;
901 
902 	if (config3 & MIPS_CONF3_MSA)
903 		c->guest.ases |= MIPS_ASE_MSA;
904 	if (config3_dyn & MIPS_CONF3_MSA)
905 		c->guest.ases_dyn |= MIPS_ASE_MSA;
906 
907 	if (config3 & MIPS_CONF_M)
908 		c->guest.conf |= BIT(4);
909 	return config3 & MIPS_CONF_M;
910 }
911 
912 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
913 {
914 	unsigned int config4;
915 
916 	probe_gc0_config(config4, config4,
917 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
918 
919 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
920 				>> MIPS_CONF4_KSCREXIST_SHIFT;
921 
922 	if (config4 & MIPS_CONF_M)
923 		c->guest.conf |= BIT(5);
924 	return config4 & MIPS_CONF_M;
925 }
926 
927 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
928 {
929 	unsigned int config5, config5_dyn;
930 
931 	probe_gc0_config_dyn(config5, config5, config5_dyn,
932 			 MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
933 
934 	if (config5 & MIPS_CONF5_MRP)
935 		c->guest.options |= MIPS_CPU_MAAR;
936 	if (config5_dyn & MIPS_CONF5_MRP)
937 		c->guest.options_dyn |= MIPS_CPU_MAAR;
938 
939 	if (config5 & MIPS_CONF5_LLB)
940 		c->guest.options |= MIPS_CPU_RW_LLB;
941 
942 	if (config5 & MIPS_CONF5_MVH)
943 		c->guest.options |= MIPS_CPU_MVH;
944 
945 	if (config5 & MIPS_CONF_M)
946 		c->guest.conf |= BIT(6);
947 	return config5 & MIPS_CONF_M;
948 }
949 
950 static inline void decode_guest_configs(struct cpuinfo_mips *c)
951 {
952 	unsigned int ok;
953 
954 	ok = decode_guest_config0(c);
955 	if (ok)
956 		ok = decode_guest_config1(c);
957 	if (ok)
958 		ok = decode_guest_config2(c);
959 	if (ok)
960 		ok = decode_guest_config3(c);
961 	if (ok)
962 		ok = decode_guest_config4(c);
963 	if (ok)
964 		decode_guest_config5(c);
965 }
966 
967 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
968 {
969 	unsigned int guestctl0, temp;
970 
971 	guestctl0 = read_c0_guestctl0();
972 
973 	if (guestctl0 & MIPS_GCTL0_G0E)
974 		c->options |= MIPS_CPU_GUESTCTL0EXT;
975 	if (guestctl0 & MIPS_GCTL0_G1)
976 		c->options |= MIPS_CPU_GUESTCTL1;
977 	if (guestctl0 & MIPS_GCTL0_G2)
978 		c->options |= MIPS_CPU_GUESTCTL2;
979 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
980 		c->options |= MIPS_CPU_GUESTID;
981 
982 		/*
983 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
984 		 * first, otherwise all data accesses will be fully virtualised
985 		 * as if they were performed by guest mode.
986 		 */
987 		write_c0_guestctl1(0);
988 		tlbw_use_hazard();
989 
990 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
991 		back_to_back_c0_hazard();
992 		temp = read_c0_guestctl0();
993 
994 		if (temp & MIPS_GCTL0_DRG) {
995 			write_c0_guestctl0(guestctl0);
996 			c->options |= MIPS_CPU_DRG;
997 		}
998 	}
999 }
1000 
1001 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1002 {
1003 	if (cpu_has_guestid) {
1004 		/* determine the number of bits of GuestID available */
1005 		write_c0_guestctl1(MIPS_GCTL1_ID);
1006 		back_to_back_c0_hazard();
1007 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1008 						>> MIPS_GCTL1_ID_SHIFT;
1009 		write_c0_guestctl1(0);
1010 	}
1011 }
1012 
1013 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1014 {
1015 	/* determine the number of bits of GTOffset available */
1016 	write_c0_gtoffset(0xffffffff);
1017 	back_to_back_c0_hazard();
1018 	c->gtoffset_mask = read_c0_gtoffset();
1019 	write_c0_gtoffset(0);
1020 }
1021 
1022 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1023 {
1024 	cpu_probe_guestctl0(c);
1025 	if (cpu_has_guestctl1)
1026 		cpu_probe_guestctl1(c);
1027 
1028 	cpu_probe_gtoffset(c);
1029 
1030 	decode_guest_configs(c);
1031 }
1032 
1033 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1034 		| MIPS_CPU_COUNTER)
1035 
1036 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1037 {
1038 	switch (c->processor_id & PRID_IMP_MASK) {
1039 	case PRID_IMP_R2000:
1040 		c->cputype = CPU_R2000;
1041 		__cpu_name[cpu] = "R2000";
1042 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1043 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1044 			     MIPS_CPU_NOFPUEX;
1045 		if (__cpu_has_fpu())
1046 			c->options |= MIPS_CPU_FPU;
1047 		c->tlbsize = 64;
1048 		break;
1049 	case PRID_IMP_R3000:
1050 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1051 			if (cpu_has_confreg()) {
1052 				c->cputype = CPU_R3081E;
1053 				__cpu_name[cpu] = "R3081";
1054 			} else {
1055 				c->cputype = CPU_R3000A;
1056 				__cpu_name[cpu] = "R3000A";
1057 			}
1058 		} else {
1059 			c->cputype = CPU_R3000;
1060 			__cpu_name[cpu] = "R3000";
1061 		}
1062 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1063 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1064 			     MIPS_CPU_NOFPUEX;
1065 		if (__cpu_has_fpu())
1066 			c->options |= MIPS_CPU_FPU;
1067 		c->tlbsize = 64;
1068 		break;
1069 	case PRID_IMP_R4000:
1070 		if (read_c0_config() & CONF_SC) {
1071 			if ((c->processor_id & PRID_REV_MASK) >=
1072 			    PRID_REV_R4400) {
1073 				c->cputype = CPU_R4400PC;
1074 				__cpu_name[cpu] = "R4400PC";
1075 			} else {
1076 				c->cputype = CPU_R4000PC;
1077 				__cpu_name[cpu] = "R4000PC";
1078 			}
1079 		} else {
1080 			int cca = read_c0_config() & CONF_CM_CMASK;
1081 			int mc;
1082 
1083 			/*
1084 			 * SC and MC versions can't be reliably told apart,
1085 			 * but only the latter support coherent caching
1086 			 * modes so assume the firmware has set the KSEG0
1087 			 * coherency attribute reasonably (if uncached, we
1088 			 * assume SC).
1089 			 */
1090 			switch (cca) {
1091 			case CONF_CM_CACHABLE_CE:
1092 			case CONF_CM_CACHABLE_COW:
1093 			case CONF_CM_CACHABLE_CUW:
1094 				mc = 1;
1095 				break;
1096 			default:
1097 				mc = 0;
1098 				break;
1099 			}
1100 			if ((c->processor_id & PRID_REV_MASK) >=
1101 			    PRID_REV_R4400) {
1102 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1103 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1104 			} else {
1105 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1106 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1107 			}
1108 		}
1109 
1110 		set_isa(c, MIPS_CPU_ISA_III);
1111 		c->fpu_msk31 |= FPU_CSR_CONDX;
1112 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1113 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1114 			     MIPS_CPU_LLSC;
1115 		c->tlbsize = 48;
1116 		break;
1117 	case PRID_IMP_VR41XX:
1118 		set_isa(c, MIPS_CPU_ISA_III);
1119 		c->fpu_msk31 |= FPU_CSR_CONDX;
1120 		c->options = R4K_OPTS;
1121 		c->tlbsize = 32;
1122 		switch (c->processor_id & 0xf0) {
1123 		case PRID_REV_VR4111:
1124 			c->cputype = CPU_VR4111;
1125 			__cpu_name[cpu] = "NEC VR4111";
1126 			break;
1127 		case PRID_REV_VR4121:
1128 			c->cputype = CPU_VR4121;
1129 			__cpu_name[cpu] = "NEC VR4121";
1130 			break;
1131 		case PRID_REV_VR4122:
1132 			if ((c->processor_id & 0xf) < 0x3) {
1133 				c->cputype = CPU_VR4122;
1134 				__cpu_name[cpu] = "NEC VR4122";
1135 			} else {
1136 				c->cputype = CPU_VR4181A;
1137 				__cpu_name[cpu] = "NEC VR4181A";
1138 			}
1139 			break;
1140 		case PRID_REV_VR4130:
1141 			if ((c->processor_id & 0xf) < 0x4) {
1142 				c->cputype = CPU_VR4131;
1143 				__cpu_name[cpu] = "NEC VR4131";
1144 			} else {
1145 				c->cputype = CPU_VR4133;
1146 				c->options |= MIPS_CPU_LLSC;
1147 				__cpu_name[cpu] = "NEC VR4133";
1148 			}
1149 			break;
1150 		default:
1151 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1152 			c->cputype = CPU_VR41XX;
1153 			__cpu_name[cpu] = "NEC Vr41xx";
1154 			break;
1155 		}
1156 		break;
1157 	case PRID_IMP_R4600:
1158 		c->cputype = CPU_R4600;
1159 		__cpu_name[cpu] = "R4600";
1160 		set_isa(c, MIPS_CPU_ISA_III);
1161 		c->fpu_msk31 |= FPU_CSR_CONDX;
1162 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1163 			     MIPS_CPU_LLSC;
1164 		c->tlbsize = 48;
1165 		break;
1166 	#if 0
1167 	case PRID_IMP_R4650:
1168 		/*
1169 		 * This processor doesn't have an MMU, so it's not
1170 		 * "real easy" to run Linux on it. It is left purely
1171 		 * for documentation.  Commented out because it shares
1172 		 * it's c0_prid id number with the TX3900.
1173 		 */
1174 		c->cputype = CPU_R4650;
1175 		__cpu_name[cpu] = "R4650";
1176 		set_isa(c, MIPS_CPU_ISA_III);
1177 		c->fpu_msk31 |= FPU_CSR_CONDX;
1178 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1179 		c->tlbsize = 48;
1180 		break;
1181 	#endif
1182 	case PRID_IMP_TX39:
1183 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1184 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1185 
1186 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1187 			c->cputype = CPU_TX3927;
1188 			__cpu_name[cpu] = "TX3927";
1189 			c->tlbsize = 64;
1190 		} else {
1191 			switch (c->processor_id & PRID_REV_MASK) {
1192 			case PRID_REV_TX3912:
1193 				c->cputype = CPU_TX3912;
1194 				__cpu_name[cpu] = "TX3912";
1195 				c->tlbsize = 32;
1196 				break;
1197 			case PRID_REV_TX3922:
1198 				c->cputype = CPU_TX3922;
1199 				__cpu_name[cpu] = "TX3922";
1200 				c->tlbsize = 64;
1201 				break;
1202 			}
1203 		}
1204 		break;
1205 	case PRID_IMP_R4700:
1206 		c->cputype = CPU_R4700;
1207 		__cpu_name[cpu] = "R4700";
1208 		set_isa(c, MIPS_CPU_ISA_III);
1209 		c->fpu_msk31 |= FPU_CSR_CONDX;
1210 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1211 			     MIPS_CPU_LLSC;
1212 		c->tlbsize = 48;
1213 		break;
1214 	case PRID_IMP_TX49:
1215 		c->cputype = CPU_TX49XX;
1216 		__cpu_name[cpu] = "R49XX";
1217 		set_isa(c, MIPS_CPU_ISA_III);
1218 		c->fpu_msk31 |= FPU_CSR_CONDX;
1219 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1220 		if (!(c->processor_id & 0x08))
1221 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1222 		c->tlbsize = 48;
1223 		break;
1224 	case PRID_IMP_R5000:
1225 		c->cputype = CPU_R5000;
1226 		__cpu_name[cpu] = "R5000";
1227 		set_isa(c, MIPS_CPU_ISA_IV);
1228 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1229 			     MIPS_CPU_LLSC;
1230 		c->tlbsize = 48;
1231 		break;
1232 	case PRID_IMP_R5500:
1233 		c->cputype = CPU_R5500;
1234 		__cpu_name[cpu] = "R5500";
1235 		set_isa(c, MIPS_CPU_ISA_IV);
1236 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1237 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1238 		c->tlbsize = 48;
1239 		break;
1240 	case PRID_IMP_NEVADA:
1241 		c->cputype = CPU_NEVADA;
1242 		__cpu_name[cpu] = "Nevada";
1243 		set_isa(c, MIPS_CPU_ISA_IV);
1244 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1245 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1246 		c->tlbsize = 48;
1247 		break;
1248 	case PRID_IMP_RM7000:
1249 		c->cputype = CPU_RM7000;
1250 		__cpu_name[cpu] = "RM7000";
1251 		set_isa(c, MIPS_CPU_ISA_IV);
1252 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1253 			     MIPS_CPU_LLSC;
1254 		/*
1255 		 * Undocumented RM7000:	 Bit 29 in the info register of
1256 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1257 		 * entries.
1258 		 *
1259 		 * 29	   1 =>	   64 entry JTLB
1260 		 *	   0 =>	   48 entry JTLB
1261 		 */
1262 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1263 		break;
1264 	case PRID_IMP_R10000:
1265 		c->cputype = CPU_R10000;
1266 		__cpu_name[cpu] = "R10000";
1267 		set_isa(c, MIPS_CPU_ISA_IV);
1268 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1269 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1270 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1271 			     MIPS_CPU_LLSC;
1272 		c->tlbsize = 64;
1273 		break;
1274 	case PRID_IMP_R12000:
1275 		c->cputype = CPU_R12000;
1276 		__cpu_name[cpu] = "R12000";
1277 		set_isa(c, MIPS_CPU_ISA_IV);
1278 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1279 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1280 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1281 			     MIPS_CPU_LLSC;
1282 		c->tlbsize = 64;
1283 		write_c0_r10k_diag(read_c0_r10k_diag() | R10K_DIAG_E_GHIST);
1284 		break;
1285 	case PRID_IMP_R14000:
1286 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1287 			c->cputype = CPU_R16000;
1288 			__cpu_name[cpu] = "R16000";
1289 		} else {
1290 			c->cputype = CPU_R14000;
1291 			__cpu_name[cpu] = "R14000";
1292 		}
1293 		set_isa(c, MIPS_CPU_ISA_IV);
1294 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1295 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1296 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1297 			     MIPS_CPU_LLSC;
1298 		c->tlbsize = 64;
1299 		write_c0_r10k_diag(read_c0_r10k_diag() | R10K_DIAG_E_GHIST);
1300 		break;
1301 	case PRID_IMP_LOONGSON_64C:  /* Loongson-2/3 */
1302 		switch (c->processor_id & PRID_REV_MASK) {
1303 		case PRID_REV_LOONGSON2E:
1304 			c->cputype = CPU_LOONGSON2EF;
1305 			__cpu_name[cpu] = "ICT Loongson-2";
1306 			set_elf_platform(cpu, "loongson2e");
1307 			set_isa(c, MIPS_CPU_ISA_III);
1308 			c->fpu_msk31 |= FPU_CSR_CONDX;
1309 			break;
1310 		case PRID_REV_LOONGSON2F:
1311 			c->cputype = CPU_LOONGSON2EF;
1312 			__cpu_name[cpu] = "ICT Loongson-2";
1313 			set_elf_platform(cpu, "loongson2f");
1314 			set_isa(c, MIPS_CPU_ISA_III);
1315 			c->fpu_msk31 |= FPU_CSR_CONDX;
1316 			break;
1317 		case PRID_REV_LOONGSON3A_R1:
1318 			c->cputype = CPU_LOONGSON64;
1319 			__cpu_name[cpu] = "ICT Loongson-3";
1320 			set_elf_platform(cpu, "loongson3a");
1321 			set_isa(c, MIPS_CPU_ISA_M64R1);
1322 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1323 				MIPS_ASE_LOONGSON_EXT);
1324 			break;
1325 		case PRID_REV_LOONGSON3B_R1:
1326 		case PRID_REV_LOONGSON3B_R2:
1327 			c->cputype = CPU_LOONGSON64;
1328 			__cpu_name[cpu] = "ICT Loongson-3";
1329 			set_elf_platform(cpu, "loongson3b");
1330 			set_isa(c, MIPS_CPU_ISA_M64R1);
1331 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1332 				MIPS_ASE_LOONGSON_EXT);
1333 			break;
1334 		}
1335 
1336 		c->options = R4K_OPTS |
1337 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1338 			     MIPS_CPU_32FPR;
1339 		c->tlbsize = 64;
1340 		set_cpu_asid_mask(c, MIPS_ENTRYHI_ASID);
1341 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1342 		break;
1343 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1344 		decode_configs(c);
1345 
1346 		c->cputype = CPU_LOONGSON32;
1347 
1348 		switch (c->processor_id & PRID_REV_MASK) {
1349 		case PRID_REV_LOONGSON1B:
1350 			__cpu_name[cpu] = "Loongson 1B";
1351 			break;
1352 		}
1353 
1354 		break;
1355 	}
1356 }
1357 
1358 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1359 {
1360 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1361 	switch (c->processor_id & PRID_IMP_MASK) {
1362 	case PRID_IMP_QEMU_GENERIC:
1363 		c->writecombine = _CACHE_UNCACHED;
1364 		c->cputype = CPU_QEMU_GENERIC;
1365 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1366 		break;
1367 	case PRID_IMP_4KC:
1368 		c->cputype = CPU_4KC;
1369 		c->writecombine = _CACHE_UNCACHED;
1370 		__cpu_name[cpu] = "MIPS 4Kc";
1371 		break;
1372 	case PRID_IMP_4KEC:
1373 	case PRID_IMP_4KECR2:
1374 		c->cputype = CPU_4KEC;
1375 		c->writecombine = _CACHE_UNCACHED;
1376 		__cpu_name[cpu] = "MIPS 4KEc";
1377 		break;
1378 	case PRID_IMP_4KSC:
1379 	case PRID_IMP_4KSD:
1380 		c->cputype = CPU_4KSC;
1381 		c->writecombine = _CACHE_UNCACHED;
1382 		__cpu_name[cpu] = "MIPS 4KSc";
1383 		break;
1384 	case PRID_IMP_5KC:
1385 		c->cputype = CPU_5KC;
1386 		c->writecombine = _CACHE_UNCACHED;
1387 		__cpu_name[cpu] = "MIPS 5Kc";
1388 		break;
1389 	case PRID_IMP_5KE:
1390 		c->cputype = CPU_5KE;
1391 		c->writecombine = _CACHE_UNCACHED;
1392 		__cpu_name[cpu] = "MIPS 5KE";
1393 		break;
1394 	case PRID_IMP_20KC:
1395 		c->cputype = CPU_20KC;
1396 		c->writecombine = _CACHE_UNCACHED;
1397 		__cpu_name[cpu] = "MIPS 20Kc";
1398 		break;
1399 	case PRID_IMP_24K:
1400 		c->cputype = CPU_24K;
1401 		c->writecombine = _CACHE_UNCACHED;
1402 		__cpu_name[cpu] = "MIPS 24Kc";
1403 		break;
1404 	case PRID_IMP_24KE:
1405 		c->cputype = CPU_24K;
1406 		c->writecombine = _CACHE_UNCACHED;
1407 		__cpu_name[cpu] = "MIPS 24KEc";
1408 		break;
1409 	case PRID_IMP_25KF:
1410 		c->cputype = CPU_25KF;
1411 		c->writecombine = _CACHE_UNCACHED;
1412 		__cpu_name[cpu] = "MIPS 25Kc";
1413 		break;
1414 	case PRID_IMP_34K:
1415 		c->cputype = CPU_34K;
1416 		c->writecombine = _CACHE_UNCACHED;
1417 		__cpu_name[cpu] = "MIPS 34Kc";
1418 		cpu_set_mt_per_tc_perf(c);
1419 		break;
1420 	case PRID_IMP_74K:
1421 		c->cputype = CPU_74K;
1422 		c->writecombine = _CACHE_UNCACHED;
1423 		__cpu_name[cpu] = "MIPS 74Kc";
1424 		break;
1425 	case PRID_IMP_M14KC:
1426 		c->cputype = CPU_M14KC;
1427 		c->writecombine = _CACHE_UNCACHED;
1428 		__cpu_name[cpu] = "MIPS M14Kc";
1429 		break;
1430 	case PRID_IMP_M14KEC:
1431 		c->cputype = CPU_M14KEC;
1432 		c->writecombine = _CACHE_UNCACHED;
1433 		__cpu_name[cpu] = "MIPS M14KEc";
1434 		break;
1435 	case PRID_IMP_1004K:
1436 		c->cputype = CPU_1004K;
1437 		c->writecombine = _CACHE_UNCACHED;
1438 		__cpu_name[cpu] = "MIPS 1004Kc";
1439 		cpu_set_mt_per_tc_perf(c);
1440 		break;
1441 	case PRID_IMP_1074K:
1442 		c->cputype = CPU_1074K;
1443 		c->writecombine = _CACHE_UNCACHED;
1444 		__cpu_name[cpu] = "MIPS 1074Kc";
1445 		break;
1446 	case PRID_IMP_INTERAPTIV_UP:
1447 		c->cputype = CPU_INTERAPTIV;
1448 		__cpu_name[cpu] = "MIPS interAptiv";
1449 		cpu_set_mt_per_tc_perf(c);
1450 		break;
1451 	case PRID_IMP_INTERAPTIV_MP:
1452 		c->cputype = CPU_INTERAPTIV;
1453 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1454 		cpu_set_mt_per_tc_perf(c);
1455 		break;
1456 	case PRID_IMP_PROAPTIV_UP:
1457 		c->cputype = CPU_PROAPTIV;
1458 		__cpu_name[cpu] = "MIPS proAptiv";
1459 		break;
1460 	case PRID_IMP_PROAPTIV_MP:
1461 		c->cputype = CPU_PROAPTIV;
1462 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1463 		break;
1464 	case PRID_IMP_P5600:
1465 		c->cputype = CPU_P5600;
1466 		__cpu_name[cpu] = "MIPS P5600";
1467 		break;
1468 	case PRID_IMP_P6600:
1469 		c->cputype = CPU_P6600;
1470 		__cpu_name[cpu] = "MIPS P6600";
1471 		break;
1472 	case PRID_IMP_I6400:
1473 		c->cputype = CPU_I6400;
1474 		__cpu_name[cpu] = "MIPS I6400";
1475 		break;
1476 	case PRID_IMP_I6500:
1477 		c->cputype = CPU_I6500;
1478 		__cpu_name[cpu] = "MIPS I6500";
1479 		break;
1480 	case PRID_IMP_M5150:
1481 		c->cputype = CPU_M5150;
1482 		__cpu_name[cpu] = "MIPS M5150";
1483 		break;
1484 	case PRID_IMP_M6250:
1485 		c->cputype = CPU_M6250;
1486 		__cpu_name[cpu] = "MIPS M6250";
1487 		break;
1488 	}
1489 
1490 	decode_configs(c);
1491 
1492 	spram_config();
1493 
1494 	mm_config(c);
1495 
1496 	switch (__get_cpu_type(c->cputype)) {
1497 	case CPU_M5150:
1498 	case CPU_P5600:
1499 		set_isa(c, MIPS_CPU_ISA_M32R5);
1500 		break;
1501 	case CPU_I6500:
1502 		c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
1503 		fallthrough;
1504 	case CPU_I6400:
1505 		c->options |= MIPS_CPU_SHARED_FTLB_RAM;
1506 		fallthrough;
1507 	default:
1508 		break;
1509 	}
1510 
1511 	/* Recent MIPS cores use the implementation-dependent ExcCode 16 for
1512 	 * cache/FTLB parity exceptions.
1513 	 */
1514 	switch (__get_cpu_type(c->cputype)) {
1515 	case CPU_PROAPTIV:
1516 	case CPU_P5600:
1517 	case CPU_P6600:
1518 	case CPU_I6400:
1519 	case CPU_I6500:
1520 		c->options |= MIPS_CPU_FTLBPAREX;
1521 		break;
1522 	}
1523 }
1524 
1525 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1526 {
1527 	decode_configs(c);
1528 	switch (c->processor_id & PRID_IMP_MASK) {
1529 	case PRID_IMP_AU1_REV1:
1530 	case PRID_IMP_AU1_REV2:
1531 		c->cputype = CPU_ALCHEMY;
1532 		switch ((c->processor_id >> 24) & 0xff) {
1533 		case 0:
1534 			__cpu_name[cpu] = "Au1000";
1535 			break;
1536 		case 1:
1537 			__cpu_name[cpu] = "Au1500";
1538 			break;
1539 		case 2:
1540 			__cpu_name[cpu] = "Au1100";
1541 			break;
1542 		case 3:
1543 			__cpu_name[cpu] = "Au1550";
1544 			break;
1545 		case 4:
1546 			__cpu_name[cpu] = "Au1200";
1547 			if ((c->processor_id & PRID_REV_MASK) == 2)
1548 				__cpu_name[cpu] = "Au1250";
1549 			break;
1550 		case 5:
1551 			__cpu_name[cpu] = "Au1210";
1552 			break;
1553 		default:
1554 			__cpu_name[cpu] = "Au1xxx";
1555 			break;
1556 		}
1557 		break;
1558 	}
1559 }
1560 
1561 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1562 {
1563 	decode_configs(c);
1564 
1565 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1566 	switch (c->processor_id & PRID_IMP_MASK) {
1567 	case PRID_IMP_SB1:
1568 		c->cputype = CPU_SB1;
1569 		__cpu_name[cpu] = "SiByte SB1";
1570 		/* FPU in pass1 is known to have issues. */
1571 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1572 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1573 		break;
1574 	case PRID_IMP_SB1A:
1575 		c->cputype = CPU_SB1A;
1576 		__cpu_name[cpu] = "SiByte SB1A";
1577 		break;
1578 	}
1579 }
1580 
1581 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1582 {
1583 	decode_configs(c);
1584 	switch (c->processor_id & PRID_IMP_MASK) {
1585 	case PRID_IMP_SR71000:
1586 		c->cputype = CPU_SR71000;
1587 		__cpu_name[cpu] = "Sandcraft SR71000";
1588 		c->scache.ways = 8;
1589 		c->tlbsize = 64;
1590 		break;
1591 	}
1592 }
1593 
1594 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1595 {
1596 	decode_configs(c);
1597 	switch (c->processor_id & PRID_IMP_MASK) {
1598 	case PRID_IMP_PR4450:
1599 		c->cputype = CPU_PR4450;
1600 		__cpu_name[cpu] = "Philips PR4450";
1601 		set_isa(c, MIPS_CPU_ISA_M32R1);
1602 		break;
1603 	}
1604 }
1605 
1606 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1607 {
1608 	decode_configs(c);
1609 	switch (c->processor_id & PRID_IMP_MASK) {
1610 	case PRID_IMP_BMIPS32_REV4:
1611 	case PRID_IMP_BMIPS32_REV8:
1612 		c->cputype = CPU_BMIPS32;
1613 		__cpu_name[cpu] = "Broadcom BMIPS32";
1614 		set_elf_platform(cpu, "bmips32");
1615 		break;
1616 	case PRID_IMP_BMIPS3300:
1617 	case PRID_IMP_BMIPS3300_ALT:
1618 	case PRID_IMP_BMIPS3300_BUG:
1619 		c->cputype = CPU_BMIPS3300;
1620 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1621 		set_elf_platform(cpu, "bmips3300");
1622 		break;
1623 	case PRID_IMP_BMIPS43XX: {
1624 		int rev = c->processor_id & PRID_REV_MASK;
1625 
1626 		if (rev >= PRID_REV_BMIPS4380_LO &&
1627 				rev <= PRID_REV_BMIPS4380_HI) {
1628 			c->cputype = CPU_BMIPS4380;
1629 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1630 			set_elf_platform(cpu, "bmips4380");
1631 			c->options |= MIPS_CPU_RIXI;
1632 		} else {
1633 			c->cputype = CPU_BMIPS4350;
1634 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1635 			set_elf_platform(cpu, "bmips4350");
1636 		}
1637 		break;
1638 	}
1639 	case PRID_IMP_BMIPS5000:
1640 	case PRID_IMP_BMIPS5200:
1641 		c->cputype = CPU_BMIPS5000;
1642 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1643 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1644 		else
1645 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1646 		set_elf_platform(cpu, "bmips5000");
1647 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1648 		break;
1649 	}
1650 }
1651 
1652 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1653 {
1654 	decode_configs(c);
1655 	switch (c->processor_id & PRID_IMP_MASK) {
1656 	case PRID_IMP_CAVIUM_CN38XX:
1657 	case PRID_IMP_CAVIUM_CN31XX:
1658 	case PRID_IMP_CAVIUM_CN30XX:
1659 		c->cputype = CPU_CAVIUM_OCTEON;
1660 		__cpu_name[cpu] = "Cavium Octeon";
1661 		goto platform;
1662 	case PRID_IMP_CAVIUM_CN58XX:
1663 	case PRID_IMP_CAVIUM_CN56XX:
1664 	case PRID_IMP_CAVIUM_CN50XX:
1665 	case PRID_IMP_CAVIUM_CN52XX:
1666 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1667 		__cpu_name[cpu] = "Cavium Octeon+";
1668 platform:
1669 		set_elf_platform(cpu, "octeon");
1670 		break;
1671 	case PRID_IMP_CAVIUM_CN61XX:
1672 	case PRID_IMP_CAVIUM_CN63XX:
1673 	case PRID_IMP_CAVIUM_CN66XX:
1674 	case PRID_IMP_CAVIUM_CN68XX:
1675 	case PRID_IMP_CAVIUM_CNF71XX:
1676 		c->cputype = CPU_CAVIUM_OCTEON2;
1677 		__cpu_name[cpu] = "Cavium Octeon II";
1678 		set_elf_platform(cpu, "octeon2");
1679 		break;
1680 	case PRID_IMP_CAVIUM_CN70XX:
1681 	case PRID_IMP_CAVIUM_CN73XX:
1682 	case PRID_IMP_CAVIUM_CNF75XX:
1683 	case PRID_IMP_CAVIUM_CN78XX:
1684 		c->cputype = CPU_CAVIUM_OCTEON3;
1685 		__cpu_name[cpu] = "Cavium Octeon III";
1686 		set_elf_platform(cpu, "octeon3");
1687 		break;
1688 	default:
1689 		printk(KERN_INFO "Unknown Octeon chip!\n");
1690 		c->cputype = CPU_UNKNOWN;
1691 		break;
1692 	}
1693 }
1694 
1695 #ifdef CONFIG_CPU_LOONGSON64
1696 #include <loongson_regs.h>
1697 
1698 static inline void decode_cpucfg(struct cpuinfo_mips *c)
1699 {
1700 	u32 cfg1 = read_cpucfg(LOONGSON_CFG1);
1701 	u32 cfg2 = read_cpucfg(LOONGSON_CFG2);
1702 	u32 cfg3 = read_cpucfg(LOONGSON_CFG3);
1703 
1704 	if (cfg1 & LOONGSON_CFG1_MMI)
1705 		c->ases |= MIPS_ASE_LOONGSON_MMI;
1706 
1707 	if (cfg2 & LOONGSON_CFG2_LEXT1)
1708 		c->ases |= MIPS_ASE_LOONGSON_EXT;
1709 
1710 	if (cfg2 & LOONGSON_CFG2_LEXT2)
1711 		c->ases |= MIPS_ASE_LOONGSON_EXT2;
1712 
1713 	if (cfg2 & LOONGSON_CFG2_LSPW) {
1714 		c->options |= MIPS_CPU_LDPTE;
1715 		c->guest.options |= MIPS_CPU_LDPTE;
1716 	}
1717 
1718 	if (cfg3 & LOONGSON_CFG3_LCAMP)
1719 		c->ases |= MIPS_ASE_LOONGSON_CAM;
1720 }
1721 
1722 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
1723 {
1724 	decode_configs(c);
1725 
1726 	/* All Loongson processors covered here define ExcCode 16 as GSExc. */
1727 	c->options |= MIPS_CPU_GSEXCEX;
1728 
1729 	switch (c->processor_id & PRID_IMP_MASK) {
1730 	case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */
1731 		switch (c->processor_id & PRID_REV_MASK) {
1732 		case PRID_REV_LOONGSON2K_R1_0:
1733 		case PRID_REV_LOONGSON2K_R1_1:
1734 		case PRID_REV_LOONGSON2K_R1_2:
1735 		case PRID_REV_LOONGSON2K_R1_3:
1736 			c->cputype = CPU_LOONGSON64;
1737 			__cpu_name[cpu] = "Loongson-2K";
1738 			set_elf_platform(cpu, "gs264e");
1739 			set_isa(c, MIPS_CPU_ISA_M64R2);
1740 			break;
1741 		}
1742 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1743 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT |
1744 				MIPS_ASE_LOONGSON_EXT2);
1745 		break;
1746 	case PRID_IMP_LOONGSON_64C:  /* Loongson-3 Classic */
1747 		switch (c->processor_id & PRID_REV_MASK) {
1748 		case PRID_REV_LOONGSON3A_R2_0:
1749 		case PRID_REV_LOONGSON3A_R2_1:
1750 			c->cputype = CPU_LOONGSON64;
1751 			__cpu_name[cpu] = "ICT Loongson-3";
1752 			set_elf_platform(cpu, "loongson3a");
1753 			set_isa(c, MIPS_CPU_ISA_M64R2);
1754 			break;
1755 		case PRID_REV_LOONGSON3A_R3_0:
1756 		case PRID_REV_LOONGSON3A_R3_1:
1757 			c->cputype = CPU_LOONGSON64;
1758 			__cpu_name[cpu] = "ICT Loongson-3";
1759 			set_elf_platform(cpu, "loongson3a");
1760 			set_isa(c, MIPS_CPU_ISA_M64R2);
1761 			break;
1762 		}
1763 		/*
1764 		 * Loongson-3 Classic did not implement MIPS standard TLBINV
1765 		 * but implemented TLBINVF and EHINV. As currently we're only
1766 		 * using these two features, enable MIPS_CPU_TLBINV as well.
1767 		 *
1768 		 * Also some early Loongson-3A2000 had wrong TLB type in Config
1769 		 * register, we correct it here.
1770 		 */
1771 		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
1772 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1773 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1774 			MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
1775 		c->ases &= ~MIPS_ASE_VZ; /* VZ of Loongson-3A2000/3000 is incomplete */
1776 		break;
1777 	case PRID_IMP_LOONGSON_64G:
1778 		c->cputype = CPU_LOONGSON64;
1779 		__cpu_name[cpu] = "ICT Loongson-3";
1780 		set_elf_platform(cpu, "loongson3a");
1781 		set_isa(c, MIPS_CPU_ISA_M64R2);
1782 		decode_cpucfg(c);
1783 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1784 		break;
1785 	default:
1786 		panic("Unknown Loongson Processor ID!");
1787 		break;
1788 	}
1789 }
1790 #else
1791 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { }
1792 #endif
1793 
1794 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1795 {
1796 	decode_configs(c);
1797 
1798 	/*
1799 	 * XBurst misses a config2 register, so config3 decode was skipped in
1800 	 * decode_configs().
1801 	 */
1802 	decode_config3(c);
1803 
1804 	/* XBurst does not implement the CP0 counter. */
1805 	c->options &= ~MIPS_CPU_COUNTER;
1806 	BUG_ON(__builtin_constant_p(cpu_has_counter) && cpu_has_counter);
1807 
1808 	/* XBurst has virtually tagged icache */
1809 	c->icache.flags |= MIPS_CACHE_VTAG;
1810 
1811 	switch (c->processor_id & PRID_IMP_MASK) {
1812 
1813 	/* XBurst®1 with MXU1.0/MXU1.1 SIMD ISA */
1814 	case PRID_IMP_XBURST_REV1:
1815 
1816 		/*
1817 		 * The XBurst core by default attempts to avoid branch target
1818 		 * buffer lookups by detecting & special casing loops. This
1819 		 * feature will cause BogoMIPS and lpj calculate in error.
1820 		 * Set cp0 config7 bit 4 to disable this feature.
1821 		 */
1822 		set_c0_config7(MIPS_CONF7_BTB_LOOP_EN);
1823 
1824 		switch (c->processor_id & PRID_COMP_MASK) {
1825 
1826 		/*
1827 		 * The config0 register in the XBurst CPUs with a processor ID of
1828 		 * PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 compatible,
1829 		 * but they don't actually support this ISA.
1830 		 */
1831 		case PRID_COMP_INGENIC_D0:
1832 			c->isa_level &= ~MIPS_CPU_ISA_M32R2;
1833 			break;
1834 
1835 		/*
1836 		 * The config0 register in the XBurst CPUs with a processor ID of
1837 		 * PRID_COMP_INGENIC_D1 has an abandoned huge page tlb mode, this
1838 		 * mode is not compatible with the MIPS standard, it will cause
1839 		 * tlbmiss and into an infinite loop (line 21 in the tlb-funcs.S)
1840 		 * when starting the init process. After chip reset, the default
1841 		 * is HPTLB mode, Write 0xa9000000 to cp0 register 5 sel 4 to
1842 		 * switch back to VTLB mode to prevent getting stuck.
1843 		 */
1844 		case PRID_COMP_INGENIC_D1:
1845 			write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);
1846 			break;
1847 
1848 		default:
1849 			break;
1850 		}
1851 		fallthrough;
1852 
1853 	/* XBurst®1 with MXU2.0 SIMD ISA */
1854 	case PRID_IMP_XBURST_REV2:
1855 		/* Ingenic uses the WA bit to achieve write-combine memory writes */
1856 		c->writecombine = _CACHE_CACHABLE_WA;
1857 		c->cputype = CPU_XBURST;
1858 		__cpu_name[cpu] = "Ingenic XBurst";
1859 		break;
1860 
1861 	/* XBurst®2 with MXU2.1 SIMD ISA */
1862 	case PRID_IMP_XBURST2:
1863 		c->cputype = CPU_XBURST;
1864 		__cpu_name[cpu] = "Ingenic XBurst II";
1865 		break;
1866 
1867 	default:
1868 		panic("Unknown Ingenic Processor ID!");
1869 		break;
1870 	}
1871 }
1872 
1873 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1874 {
1875 	decode_configs(c);
1876 
1877 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1878 		c->cputype = CPU_ALCHEMY;
1879 		__cpu_name[cpu] = "Au1300";
1880 		/* following stuff is not for Alchemy */
1881 		return;
1882 	}
1883 
1884 	c->options = (MIPS_CPU_TLB	 |
1885 			MIPS_CPU_4KEX	 |
1886 			MIPS_CPU_COUNTER |
1887 			MIPS_CPU_DIVEC	 |
1888 			MIPS_CPU_WATCH	 |
1889 			MIPS_CPU_EJTAG	 |
1890 			MIPS_CPU_LLSC);
1891 
1892 	switch (c->processor_id & PRID_IMP_MASK) {
1893 	case PRID_IMP_NETLOGIC_XLP2XX:
1894 	case PRID_IMP_NETLOGIC_XLP9XX:
1895 	case PRID_IMP_NETLOGIC_XLP5XX:
1896 		c->cputype = CPU_XLP;
1897 		__cpu_name[cpu] = "Broadcom XLPII";
1898 		break;
1899 
1900 	case PRID_IMP_NETLOGIC_XLP8XX:
1901 	case PRID_IMP_NETLOGIC_XLP3XX:
1902 		c->cputype = CPU_XLP;
1903 		__cpu_name[cpu] = "Netlogic XLP";
1904 		break;
1905 
1906 	case PRID_IMP_NETLOGIC_XLR732:
1907 	case PRID_IMP_NETLOGIC_XLR716:
1908 	case PRID_IMP_NETLOGIC_XLR532:
1909 	case PRID_IMP_NETLOGIC_XLR308:
1910 	case PRID_IMP_NETLOGIC_XLR532C:
1911 	case PRID_IMP_NETLOGIC_XLR516C:
1912 	case PRID_IMP_NETLOGIC_XLR508C:
1913 	case PRID_IMP_NETLOGIC_XLR308C:
1914 		c->cputype = CPU_XLR;
1915 		__cpu_name[cpu] = "Netlogic XLR";
1916 		break;
1917 
1918 	case PRID_IMP_NETLOGIC_XLS608:
1919 	case PRID_IMP_NETLOGIC_XLS408:
1920 	case PRID_IMP_NETLOGIC_XLS404:
1921 	case PRID_IMP_NETLOGIC_XLS208:
1922 	case PRID_IMP_NETLOGIC_XLS204:
1923 	case PRID_IMP_NETLOGIC_XLS108:
1924 	case PRID_IMP_NETLOGIC_XLS104:
1925 	case PRID_IMP_NETLOGIC_XLS616B:
1926 	case PRID_IMP_NETLOGIC_XLS608B:
1927 	case PRID_IMP_NETLOGIC_XLS416B:
1928 	case PRID_IMP_NETLOGIC_XLS412B:
1929 	case PRID_IMP_NETLOGIC_XLS408B:
1930 	case PRID_IMP_NETLOGIC_XLS404B:
1931 		c->cputype = CPU_XLR;
1932 		__cpu_name[cpu] = "Netlogic XLS";
1933 		break;
1934 
1935 	default:
1936 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1937 		       c->processor_id);
1938 		c->cputype = CPU_XLR;
1939 		break;
1940 	}
1941 
1942 	if (c->cputype == CPU_XLP) {
1943 		set_isa(c, MIPS_CPU_ISA_M64R2);
1944 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1945 		/* This will be updated again after all threads are woken up */
1946 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1947 	} else {
1948 		set_isa(c, MIPS_CPU_ISA_M64R1);
1949 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1950 	}
1951 	c->kscratch_mask = 0xf;
1952 }
1953 
1954 #ifdef CONFIG_64BIT
1955 /* For use by uaccess.h */
1956 u64 __ua_limit;
1957 EXPORT_SYMBOL(__ua_limit);
1958 #endif
1959 
1960 const char *__cpu_name[NR_CPUS];
1961 const char *__elf_platform;
1962 const char *__elf_base_platform;
1963 
1964 void cpu_probe(void)
1965 {
1966 	struct cpuinfo_mips *c = &current_cpu_data;
1967 	unsigned int cpu = smp_processor_id();
1968 
1969 	/*
1970 	 * Set a default elf platform, cpu probe may later
1971 	 * overwrite it with a more precise value
1972 	 */
1973 	set_elf_platform(cpu, "mips");
1974 
1975 	c->processor_id = PRID_IMP_UNKNOWN;
1976 	c->fpu_id	= FPIR_IMP_NONE;
1977 	c->cputype	= CPU_UNKNOWN;
1978 	c->writecombine = _CACHE_UNCACHED;
1979 
1980 	c->fpu_csr31	= FPU_CSR_RN;
1981 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
1982 
1983 	c->processor_id = read_c0_prid();
1984 	switch (c->processor_id & PRID_COMP_MASK) {
1985 	case PRID_COMP_LEGACY:
1986 		cpu_probe_legacy(c, cpu);
1987 		break;
1988 	case PRID_COMP_MIPS:
1989 		cpu_probe_mips(c, cpu);
1990 		break;
1991 	case PRID_COMP_ALCHEMY:
1992 		cpu_probe_alchemy(c, cpu);
1993 		break;
1994 	case PRID_COMP_SIBYTE:
1995 		cpu_probe_sibyte(c, cpu);
1996 		break;
1997 	case PRID_COMP_BROADCOM:
1998 		cpu_probe_broadcom(c, cpu);
1999 		break;
2000 	case PRID_COMP_SANDCRAFT:
2001 		cpu_probe_sandcraft(c, cpu);
2002 		break;
2003 	case PRID_COMP_NXP:
2004 		cpu_probe_nxp(c, cpu);
2005 		break;
2006 	case PRID_COMP_CAVIUM:
2007 		cpu_probe_cavium(c, cpu);
2008 		break;
2009 	case PRID_COMP_LOONGSON:
2010 		cpu_probe_loongson(c, cpu);
2011 		break;
2012 	case PRID_COMP_INGENIC_13:
2013 	case PRID_COMP_INGENIC_D0:
2014 	case PRID_COMP_INGENIC_D1:
2015 	case PRID_COMP_INGENIC_E1:
2016 		cpu_probe_ingenic(c, cpu);
2017 		break;
2018 	case PRID_COMP_NETLOGIC:
2019 		cpu_probe_netlogic(c, cpu);
2020 		break;
2021 	}
2022 
2023 	BUG_ON(!__cpu_name[cpu]);
2024 	BUG_ON(c->cputype == CPU_UNKNOWN);
2025 
2026 	/*
2027 	 * Platform code can force the cpu type to optimize code
2028 	 * generation. In that case be sure the cpu type is correctly
2029 	 * manually setup otherwise it could trigger some nasty bugs.
2030 	 */
2031 	BUG_ON(current_cpu_type() != c->cputype);
2032 
2033 	if (cpu_has_rixi) {
2034 		/* Enable the RIXI exceptions */
2035 		set_c0_pagegrain(PG_IEC);
2036 		back_to_back_c0_hazard();
2037 		/* Verify the IEC bit is set */
2038 		if (read_c0_pagegrain() & PG_IEC)
2039 			c->options |= MIPS_CPU_RIXIEX;
2040 	}
2041 
2042 	if (mips_fpu_disabled)
2043 		c->options &= ~MIPS_CPU_FPU;
2044 
2045 	if (mips_dsp_disabled)
2046 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2047 
2048 	if (mips_htw_disabled) {
2049 		c->options &= ~MIPS_CPU_HTW;
2050 		write_c0_pwctl(read_c0_pwctl() &
2051 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2052 	}
2053 
2054 	if (c->options & MIPS_CPU_FPU)
2055 		cpu_set_fpu_opts(c);
2056 	else
2057 		cpu_set_nofpu_opts(c);
2058 
2059 	if (cpu_has_mips_r2_r6) {
2060 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2061 		/* R2 has Performance Counter Interrupt indicator */
2062 		c->options |= MIPS_CPU_PCI;
2063 	}
2064 	else
2065 		c->srsets = 1;
2066 
2067 	if (cpu_has_mips_r6)
2068 		elf_hwcap |= HWCAP_MIPS_R6;
2069 
2070 	if (cpu_has_msa) {
2071 		c->msa_id = cpu_get_msa_id();
2072 		WARN(c->msa_id & MSA_IR_WRPF,
2073 		     "Vector register partitioning unimplemented!");
2074 		elf_hwcap |= HWCAP_MIPS_MSA;
2075 	}
2076 
2077 	if (cpu_has_mips16)
2078 		elf_hwcap |= HWCAP_MIPS_MIPS16;
2079 
2080 	if (cpu_has_mdmx)
2081 		elf_hwcap |= HWCAP_MIPS_MDMX;
2082 
2083 	if (cpu_has_mips3d)
2084 		elf_hwcap |= HWCAP_MIPS_MIPS3D;
2085 
2086 	if (cpu_has_smartmips)
2087 		elf_hwcap |= HWCAP_MIPS_SMARTMIPS;
2088 
2089 	if (cpu_has_dsp)
2090 		elf_hwcap |= HWCAP_MIPS_DSP;
2091 
2092 	if (cpu_has_dsp2)
2093 		elf_hwcap |= HWCAP_MIPS_DSP2;
2094 
2095 	if (cpu_has_dsp3)
2096 		elf_hwcap |= HWCAP_MIPS_DSP3;
2097 
2098 	if (cpu_has_mips16e2)
2099 		elf_hwcap |= HWCAP_MIPS_MIPS16E2;
2100 
2101 	if (cpu_has_loongson_mmi)
2102 		elf_hwcap |= HWCAP_LOONGSON_MMI;
2103 
2104 	if (cpu_has_loongson_ext)
2105 		elf_hwcap |= HWCAP_LOONGSON_EXT;
2106 
2107 	if (cpu_has_loongson_ext2)
2108 		elf_hwcap |= HWCAP_LOONGSON_EXT2;
2109 
2110 	if (cpu_has_vz)
2111 		cpu_probe_vz(c);
2112 
2113 	cpu_probe_vmbits(c);
2114 
2115 	/* Synthesize CPUCFG data if running on Loongson processors;
2116 	 * no-op otherwise.
2117 	 *
2118 	 * This looks at previously probed features, so keep this at bottom.
2119 	 */
2120 	loongson3_cpucfg_synthesize_data(c);
2121 
2122 #ifdef CONFIG_64BIT
2123 	if (cpu == 0)
2124 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2125 #endif
2126 }
2127 
2128 void cpu_report(void)
2129 {
2130 	struct cpuinfo_mips *c = &current_cpu_data;
2131 
2132 	pr_info("CPU%d revision is: %08x (%s)\n",
2133 		smp_processor_id(), c->processor_id, cpu_name_string());
2134 	if (c->options & MIPS_CPU_FPU)
2135 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2136 	if (cpu_has_msa)
2137 		pr_info("MSA revision is: %08x\n", c->msa_id);
2138 }
2139 
2140 void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
2141 {
2142 	/* Ensure the core number fits in the field */
2143 	WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
2144 			   MIPS_GLOBALNUMBER_CLUSTER_SHF));
2145 
2146 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
2147 	cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
2148 }
2149 
2150 void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
2151 {
2152 	/* Ensure the core number fits in the field */
2153 	WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
2154 
2155 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
2156 	cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
2157 }
2158 
2159 void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
2160 {
2161 	/* Ensure the VP(E) ID fits in the field */
2162 	WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
2163 
2164 	/* Ensure we're not using VP(E)s without support */
2165 	WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
2166 		!IS_ENABLED(CONFIG_CPU_MIPSR6));
2167 
2168 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
2169 	cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
2170 }
2171