xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 08193d1a)
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 <linux/uaccess.h>
34 
35 /* Hardware capabilities */
36 unsigned int elf_hwcap __read_mostly;
37 EXPORT_SYMBOL_GPL(elf_hwcap);
38 
39 /*
40  * Get the FPU Implementation/Revision.
41  */
42 static inline unsigned long cpu_get_fpu_id(void)
43 {
44 	unsigned long tmp, fpu_id;
45 
46 	tmp = read_c0_status();
47 	__enable_fpu(FPU_AS_IS);
48 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
49 	write_c0_status(tmp);
50 	return fpu_id;
51 }
52 
53 /*
54  * Check if the CPU has an external FPU.
55  */
56 static inline int __cpu_has_fpu(void)
57 {
58 	return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
59 }
60 
61 static inline unsigned long cpu_get_msa_id(void)
62 {
63 	unsigned long status, msa_id;
64 
65 	status = read_c0_status();
66 	__enable_fpu(FPU_64BIT);
67 	enable_msa();
68 	msa_id = read_msa_ir();
69 	disable_msa();
70 	write_c0_status(status);
71 	return msa_id;
72 }
73 
74 /*
75  * Determine the FCSR mask for FPU hardware.
76  */
77 static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_mips *c)
78 {
79 	unsigned long sr, mask, fcsr, fcsr0, fcsr1;
80 
81 	fcsr = c->fpu_csr31;
82 	mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
83 
84 	sr = read_c0_status();
85 	__enable_fpu(FPU_AS_IS);
86 
87 	fcsr0 = fcsr & mask;
88 	write_32bit_cp1_register(CP1_STATUS, fcsr0);
89 	fcsr0 = read_32bit_cp1_register(CP1_STATUS);
90 
91 	fcsr1 = fcsr | ~mask;
92 	write_32bit_cp1_register(CP1_STATUS, fcsr1);
93 	fcsr1 = read_32bit_cp1_register(CP1_STATUS);
94 
95 	write_32bit_cp1_register(CP1_STATUS, fcsr);
96 
97 	write_c0_status(sr);
98 
99 	c->fpu_msk31 = ~(fcsr0 ^ fcsr1) & ~mask;
100 }
101 
102 /*
103  * Determine the IEEE 754 NaN encodings and ABS.fmt/NEG.fmt execution modes
104  * supported by FPU hardware.
105  */
106 static void cpu_set_fpu_2008(struct cpuinfo_mips *c)
107 {
108 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
109 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
110 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
111 		unsigned long sr, fir, fcsr, fcsr0, fcsr1;
112 
113 		sr = read_c0_status();
114 		__enable_fpu(FPU_AS_IS);
115 
116 		fir = read_32bit_cp1_register(CP1_REVISION);
117 		if (fir & MIPS_FPIR_HAS2008) {
118 			fcsr = read_32bit_cp1_register(CP1_STATUS);
119 
120 			fcsr0 = fcsr & ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
121 			write_32bit_cp1_register(CP1_STATUS, fcsr0);
122 			fcsr0 = read_32bit_cp1_register(CP1_STATUS);
123 
124 			fcsr1 = fcsr | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
125 			write_32bit_cp1_register(CP1_STATUS, fcsr1);
126 			fcsr1 = read_32bit_cp1_register(CP1_STATUS);
127 
128 			write_32bit_cp1_register(CP1_STATUS, fcsr);
129 
130 			if (!(fcsr0 & FPU_CSR_NAN2008))
131 				c->options |= MIPS_CPU_NAN_LEGACY;
132 			if (fcsr1 & FPU_CSR_NAN2008)
133 				c->options |= MIPS_CPU_NAN_2008;
134 
135 			if ((fcsr0 ^ fcsr1) & FPU_CSR_ABS2008)
136 				c->fpu_msk31 &= ~FPU_CSR_ABS2008;
137 			else
138 				c->fpu_csr31 |= fcsr & FPU_CSR_ABS2008;
139 
140 			if ((fcsr0 ^ fcsr1) & FPU_CSR_NAN2008)
141 				c->fpu_msk31 &= ~FPU_CSR_NAN2008;
142 			else
143 				c->fpu_csr31 |= fcsr & FPU_CSR_NAN2008;
144 		} else {
145 			c->options |= MIPS_CPU_NAN_LEGACY;
146 		}
147 
148 		write_c0_status(sr);
149 	} else {
150 		c->options |= MIPS_CPU_NAN_LEGACY;
151 	}
152 }
153 
154 /*
155  * IEEE 754 conformance mode to use.  Affects the NaN encoding and the
156  * ABS.fmt/NEG.fmt execution mode.
157  */
158 static enum { STRICT, LEGACY, STD2008, RELAXED } ieee754 = STRICT;
159 
160 /*
161  * Set the IEEE 754 NaN encodings and the ABS.fmt/NEG.fmt execution modes
162  * to support by the FPU emulator according to the IEEE 754 conformance
163  * mode selected.  Note that "relaxed" straps the emulator so that it
164  * allows 2008-NaN binaries even for legacy processors.
165  */
166 static void cpu_set_nofpu_2008(struct cpuinfo_mips *c)
167 {
168 	c->options &= ~(MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY);
169 	c->fpu_csr31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
170 	c->fpu_msk31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
171 
172 	switch (ieee754) {
173 	case STRICT:
174 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
175 				    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
176 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
177 			c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
178 		} else {
179 			c->options |= MIPS_CPU_NAN_LEGACY;
180 			c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
181 		}
182 		break;
183 	case LEGACY:
184 		c->options |= MIPS_CPU_NAN_LEGACY;
185 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
186 		break;
187 	case STD2008:
188 		c->options |= MIPS_CPU_NAN_2008;
189 		c->fpu_csr31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
190 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
191 		break;
192 	case RELAXED:
193 		c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
194 		break;
195 	}
196 }
197 
198 /*
199  * Override the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode
200  * according to the "ieee754=" parameter.
201  */
202 static void cpu_set_nan_2008(struct cpuinfo_mips *c)
203 {
204 	switch (ieee754) {
205 	case STRICT:
206 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
207 		mips_use_nan_2008 = !!cpu_has_nan_2008;
208 		break;
209 	case LEGACY:
210 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
211 		mips_use_nan_2008 = !cpu_has_nan_legacy;
212 		break;
213 	case STD2008:
214 		mips_use_nan_legacy = !cpu_has_nan_2008;
215 		mips_use_nan_2008 = !!cpu_has_nan_2008;
216 		break;
217 	case RELAXED:
218 		mips_use_nan_legacy = true;
219 		mips_use_nan_2008 = true;
220 		break;
221 	}
222 }
223 
224 /*
225  * IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode override
226  * settings:
227  *
228  * strict:  accept binaries that request a NaN encoding supported by the FPU
229  * legacy:  only accept legacy-NaN binaries
230  * 2008:    only accept 2008-NaN binaries
231  * relaxed: accept any binaries regardless of whether supported by the FPU
232  */
233 static int __init ieee754_setup(char *s)
234 {
235 	if (!s)
236 		return -1;
237 	else if (!strcmp(s, "strict"))
238 		ieee754 = STRICT;
239 	else if (!strcmp(s, "legacy"))
240 		ieee754 = LEGACY;
241 	else if (!strcmp(s, "2008"))
242 		ieee754 = STD2008;
243 	else if (!strcmp(s, "relaxed"))
244 		ieee754 = RELAXED;
245 	else
246 		return -1;
247 
248 	if (!(boot_cpu_data.options & MIPS_CPU_FPU))
249 		cpu_set_nofpu_2008(&boot_cpu_data);
250 	cpu_set_nan_2008(&boot_cpu_data);
251 
252 	return 0;
253 }
254 
255 early_param("ieee754", ieee754_setup);
256 
257 /*
258  * Set the FIR feature flags for the FPU emulator.
259  */
260 static void cpu_set_nofpu_id(struct cpuinfo_mips *c)
261 {
262 	u32 value;
263 
264 	value = 0;
265 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
266 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
267 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
268 		value |= MIPS_FPIR_D | MIPS_FPIR_S;
269 	if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
270 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
271 		value |= MIPS_FPIR_F64 | MIPS_FPIR_L | MIPS_FPIR_W;
272 	if (c->options & MIPS_CPU_NAN_2008)
273 		value |= MIPS_FPIR_HAS2008;
274 	c->fpu_id = value;
275 }
276 
277 /* Determined FPU emulator mask to use for the boot CPU with "nofpu".  */
278 static unsigned int mips_nofpu_msk31;
279 
280 /*
281  * Set options for FPU hardware.
282  */
283 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
284 {
285 	c->fpu_id = cpu_get_fpu_id();
286 	mips_nofpu_msk31 = c->fpu_msk31;
287 
288 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
289 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
290 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
291 		if (c->fpu_id & MIPS_FPIR_3D)
292 			c->ases |= MIPS_ASE_MIPS3D;
293 		if (c->fpu_id & MIPS_FPIR_UFRP)
294 			c->options |= MIPS_CPU_UFR;
295 		if (c->fpu_id & MIPS_FPIR_FREP)
296 			c->options |= MIPS_CPU_FRE;
297 	}
298 
299 	cpu_set_fpu_fcsr_mask(c);
300 	cpu_set_fpu_2008(c);
301 	cpu_set_nan_2008(c);
302 }
303 
304 /*
305  * Set options for the FPU emulator.
306  */
307 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
308 {
309 	c->options &= ~MIPS_CPU_FPU;
310 	c->fpu_msk31 = mips_nofpu_msk31;
311 
312 	cpu_set_nofpu_2008(c);
313 	cpu_set_nan_2008(c);
314 	cpu_set_nofpu_id(c);
315 }
316 
317 static int mips_fpu_disabled;
318 
319 static int __init fpu_disable(char *s)
320 {
321 	cpu_set_nofpu_opts(&boot_cpu_data);
322 	mips_fpu_disabled = 1;
323 
324 	return 1;
325 }
326 
327 __setup("nofpu", fpu_disable);
328 
329 static int mips_dsp_disabled;
330 
331 static int __init dsp_disable(char *s)
332 {
333 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
334 	mips_dsp_disabled = 1;
335 
336 	return 1;
337 }
338 
339 __setup("nodsp", dsp_disable);
340 
341 static int mips_htw_disabled;
342 
343 static int __init htw_disable(char *s)
344 {
345 	mips_htw_disabled = 1;
346 	cpu_data[0].options &= ~MIPS_CPU_HTW;
347 	write_c0_pwctl(read_c0_pwctl() &
348 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
349 
350 	return 1;
351 }
352 
353 __setup("nohtw", htw_disable);
354 
355 static int mips_ftlb_disabled;
356 static int mips_has_ftlb_configured;
357 
358 enum ftlb_flags {
359 	FTLB_EN		= 1 << 0,
360 	FTLB_SET_PROB	= 1 << 1,
361 };
362 
363 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
364 
365 static int __init ftlb_disable(char *s)
366 {
367 	unsigned int config4, mmuextdef;
368 
369 	/*
370 	 * If the core hasn't done any FTLB configuration, there is nothing
371 	 * for us to do here.
372 	 */
373 	if (!mips_has_ftlb_configured)
374 		return 1;
375 
376 	/* Disable it in the boot cpu */
377 	if (set_ftlb_enable(&cpu_data[0], 0)) {
378 		pr_warn("Can't turn FTLB off\n");
379 		return 1;
380 	}
381 
382 	config4 = read_c0_config4();
383 
384 	/* Check that FTLB has been disabled */
385 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
386 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
387 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
388 		/* This should never happen */
389 		pr_warn("FTLB could not be disabled!\n");
390 		return 1;
391 	}
392 
393 	mips_ftlb_disabled = 1;
394 	mips_has_ftlb_configured = 0;
395 
396 	/*
397 	 * noftlb is mainly used for debug purposes so print
398 	 * an informative message instead of using pr_debug()
399 	 */
400 	pr_info("FTLB has been disabled\n");
401 
402 	/*
403 	 * Some of these bits are duplicated in the decode_config4.
404 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
405 	 * once FTLB has been disabled so undo what decode_config4 did.
406 	 */
407 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
408 			       cpu_data[0].tlbsizeftlbsets;
409 	cpu_data[0].tlbsizeftlbsets = 0;
410 	cpu_data[0].tlbsizeftlbways = 0;
411 
412 	return 1;
413 }
414 
415 __setup("noftlb", ftlb_disable);
416 
417 /*
418  * Check if the CPU has per tc perf counters
419  */
420 static inline void cpu_set_mt_per_tc_perf(struct cpuinfo_mips *c)
421 {
422 	if (read_c0_config7() & MTI_CONF7_PTC)
423 		c->options |= MIPS_CPU_MT_PER_TC_PERF_COUNTERS;
424 }
425 
426 static inline void check_errata(void)
427 {
428 	struct cpuinfo_mips *c = &current_cpu_data;
429 
430 	switch (current_cpu_type()) {
431 	case CPU_34K:
432 		/*
433 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
434 		 * This code only handles VPE0, any SMP/RTOS code
435 		 * making use of VPE1 will be responsable for that VPE.
436 		 */
437 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
438 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
439 		break;
440 	default:
441 		break;
442 	}
443 }
444 
445 void __init check_bugs32(void)
446 {
447 	check_errata();
448 }
449 
450 /*
451  * Probe whether cpu has config register by trying to play with
452  * alternate cache bit and see whether it matters.
453  * It's used by cpu_probe to distinguish between R3000A and R3081.
454  */
455 static inline int cpu_has_confreg(void)
456 {
457 #ifdef CONFIG_CPU_R3000
458 	extern unsigned long r3k_cache_size(unsigned long);
459 	unsigned long size1, size2;
460 	unsigned long cfg = read_c0_conf();
461 
462 	size1 = r3k_cache_size(ST0_ISC);
463 	write_c0_conf(cfg ^ R30XX_CONF_AC);
464 	size2 = r3k_cache_size(ST0_ISC);
465 	write_c0_conf(cfg);
466 	return size1 != size2;
467 #else
468 	return 0;
469 #endif
470 }
471 
472 static inline void set_elf_platform(int cpu, const char *plat)
473 {
474 	if (cpu == 0)
475 		__elf_platform = plat;
476 }
477 
478 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
479 {
480 #ifdef __NEED_VMBITS_PROBE
481 	write_c0_entryhi(0x3fffffffffffe000ULL);
482 	back_to_back_c0_hazard();
483 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
484 #endif
485 }
486 
487 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
488 {
489 	switch (isa) {
490 	case MIPS_CPU_ISA_M64R2:
491 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
492 	case MIPS_CPU_ISA_M64R1:
493 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
494 	case MIPS_CPU_ISA_V:
495 		c->isa_level |= MIPS_CPU_ISA_V;
496 	case MIPS_CPU_ISA_IV:
497 		c->isa_level |= MIPS_CPU_ISA_IV;
498 	case MIPS_CPU_ISA_III:
499 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
500 		break;
501 
502 	/* R6 incompatible with everything else */
503 	case MIPS_CPU_ISA_M64R6:
504 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
505 	case MIPS_CPU_ISA_M32R6:
506 		c->isa_level |= MIPS_CPU_ISA_M32R6;
507 		/* Break here so we don't add incompatible ISAs */
508 		break;
509 	case MIPS_CPU_ISA_M32R2:
510 		c->isa_level |= MIPS_CPU_ISA_M32R2;
511 	case MIPS_CPU_ISA_M32R1:
512 		c->isa_level |= MIPS_CPU_ISA_M32R1;
513 	case MIPS_CPU_ISA_II:
514 		c->isa_level |= MIPS_CPU_ISA_II;
515 		break;
516 	}
517 }
518 
519 static char unknown_isa[] = KERN_ERR \
520 	"Unsupported ISA type, c0.config0: %d.";
521 
522 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
523 {
524 
525 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
526 
527 	/*
528 	 * 0 = All TLBWR instructions go to FTLB
529 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
530 	 * FTLB and 1 goes to the VTLB.
531 	 * 2 = 7:1: As above with 7:1 ratio.
532 	 * 3 = 3:1: As above with 3:1 ratio.
533 	 *
534 	 * Use the linear midpoint as the probability threshold.
535 	 */
536 	if (probability >= 12)
537 		return 1;
538 	else if (probability >= 6)
539 		return 2;
540 	else
541 		/*
542 		 * So FTLB is less than 4 times bigger than VTLB.
543 		 * A 3:1 ratio can still be useful though.
544 		 */
545 		return 3;
546 }
547 
548 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
549 {
550 	unsigned int config;
551 
552 	/* It's implementation dependent how the FTLB can be enabled */
553 	switch (c->cputype) {
554 	case CPU_PROAPTIV:
555 	case CPU_P5600:
556 	case CPU_P6600:
557 		/* proAptiv & related cores use Config6 to enable the FTLB */
558 		config = read_c0_config6();
559 
560 		if (flags & FTLB_EN)
561 			config |= MIPS_CONF6_FTLBEN;
562 		else
563 			config &= ~MIPS_CONF6_FTLBEN;
564 
565 		if (flags & FTLB_SET_PROB) {
566 			config &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
567 			config |= calculate_ftlb_probability(c)
568 				  << MIPS_CONF6_FTLBP_SHIFT;
569 		}
570 
571 		write_c0_config6(config);
572 		back_to_back_c0_hazard();
573 		break;
574 	case CPU_I6400:
575 	case CPU_I6500:
576 		/* There's no way to disable the FTLB */
577 		if (!(flags & FTLB_EN))
578 			return 1;
579 		return 0;
580 	case CPU_LOONGSON3:
581 		/* Flush ITLB, DTLB, VTLB and FTLB */
582 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
583 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
584 		/* Loongson-3 cores use Config6 to enable the FTLB */
585 		config = read_c0_config6();
586 		if (flags & FTLB_EN)
587 			/* Enable FTLB */
588 			write_c0_config6(config & ~MIPS_CONF6_FTLBDIS);
589 		else
590 			/* Disable FTLB */
591 			write_c0_config6(config | MIPS_CONF6_FTLBDIS);
592 		break;
593 	default:
594 		return 1;
595 	}
596 
597 	return 0;
598 }
599 
600 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
601 {
602 	unsigned int config0;
603 	int isa, mt;
604 
605 	config0 = read_c0_config();
606 
607 	/*
608 	 * Look for Standard TLB or Dual VTLB and FTLB
609 	 */
610 	mt = config0 & MIPS_CONF_MT;
611 	if (mt == MIPS_CONF_MT_TLB)
612 		c->options |= MIPS_CPU_TLB;
613 	else if (mt == MIPS_CONF_MT_FTLB)
614 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
615 
616 	isa = (config0 & MIPS_CONF_AT) >> 13;
617 	switch (isa) {
618 	case 0:
619 		switch ((config0 & MIPS_CONF_AR) >> 10) {
620 		case 0:
621 			set_isa(c, MIPS_CPU_ISA_M32R1);
622 			break;
623 		case 1:
624 			set_isa(c, MIPS_CPU_ISA_M32R2);
625 			break;
626 		case 2:
627 			set_isa(c, MIPS_CPU_ISA_M32R6);
628 			break;
629 		default:
630 			goto unknown;
631 		}
632 		break;
633 	case 2:
634 		switch ((config0 & MIPS_CONF_AR) >> 10) {
635 		case 0:
636 			set_isa(c, MIPS_CPU_ISA_M64R1);
637 			break;
638 		case 1:
639 			set_isa(c, MIPS_CPU_ISA_M64R2);
640 			break;
641 		case 2:
642 			set_isa(c, MIPS_CPU_ISA_M64R6);
643 			break;
644 		default:
645 			goto unknown;
646 		}
647 		break;
648 	default:
649 		goto unknown;
650 	}
651 
652 	return config0 & MIPS_CONF_M;
653 
654 unknown:
655 	panic(unknown_isa, config0);
656 }
657 
658 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
659 {
660 	unsigned int config1;
661 
662 	config1 = read_c0_config1();
663 
664 	if (config1 & MIPS_CONF1_MD)
665 		c->ases |= MIPS_ASE_MDMX;
666 	if (config1 & MIPS_CONF1_PC)
667 		c->options |= MIPS_CPU_PERF;
668 	if (config1 & MIPS_CONF1_WR)
669 		c->options |= MIPS_CPU_WATCH;
670 	if (config1 & MIPS_CONF1_CA)
671 		c->ases |= MIPS_ASE_MIPS16;
672 	if (config1 & MIPS_CONF1_EP)
673 		c->options |= MIPS_CPU_EJTAG;
674 	if (config1 & MIPS_CONF1_FP) {
675 		c->options |= MIPS_CPU_FPU;
676 		c->options |= MIPS_CPU_32FPR;
677 	}
678 	if (cpu_has_tlb) {
679 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
680 		c->tlbsizevtlb = c->tlbsize;
681 		c->tlbsizeftlbsets = 0;
682 	}
683 
684 	return config1 & MIPS_CONF_M;
685 }
686 
687 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
688 {
689 	unsigned int config2;
690 
691 	config2 = read_c0_config2();
692 
693 	if (config2 & MIPS_CONF2_SL)
694 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
695 
696 	return config2 & MIPS_CONF_M;
697 }
698 
699 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
700 {
701 	unsigned int config3;
702 
703 	config3 = read_c0_config3();
704 
705 	if (config3 & MIPS_CONF3_SM) {
706 		c->ases |= MIPS_ASE_SMARTMIPS;
707 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
708 	}
709 	if (config3 & MIPS_CONF3_RXI)
710 		c->options |= MIPS_CPU_RIXI;
711 	if (config3 & MIPS_CONF3_CTXTC)
712 		c->options |= MIPS_CPU_CTXTC;
713 	if (config3 & MIPS_CONF3_DSP)
714 		c->ases |= MIPS_ASE_DSP;
715 	if (config3 & MIPS_CONF3_DSP2P) {
716 		c->ases |= MIPS_ASE_DSP2P;
717 		if (cpu_has_mips_r6)
718 			c->ases |= MIPS_ASE_DSP3;
719 	}
720 	if (config3 & MIPS_CONF3_VINT)
721 		c->options |= MIPS_CPU_VINT;
722 	if (config3 & MIPS_CONF3_VEIC)
723 		c->options |= MIPS_CPU_VEIC;
724 	if (config3 & MIPS_CONF3_LPA)
725 		c->options |= MIPS_CPU_LPA;
726 	if (config3 & MIPS_CONF3_MT)
727 		c->ases |= MIPS_ASE_MIPSMT;
728 	if (config3 & MIPS_CONF3_ULRI)
729 		c->options |= MIPS_CPU_ULRI;
730 	if (config3 & MIPS_CONF3_ISA)
731 		c->options |= MIPS_CPU_MICROMIPS;
732 	if (config3 & MIPS_CONF3_VZ)
733 		c->ases |= MIPS_ASE_VZ;
734 	if (config3 & MIPS_CONF3_SC)
735 		c->options |= MIPS_CPU_SEGMENTS;
736 	if (config3 & MIPS_CONF3_BI)
737 		c->options |= MIPS_CPU_BADINSTR;
738 	if (config3 & MIPS_CONF3_BP)
739 		c->options |= MIPS_CPU_BADINSTRP;
740 	if (config3 & MIPS_CONF3_MSA)
741 		c->ases |= MIPS_ASE_MSA;
742 	if (config3 & MIPS_CONF3_PW) {
743 		c->htw_seq = 0;
744 		c->options |= MIPS_CPU_HTW;
745 	}
746 	if (config3 & MIPS_CONF3_CDMM)
747 		c->options |= MIPS_CPU_CDMM;
748 	if (config3 & MIPS_CONF3_SP)
749 		c->options |= MIPS_CPU_SP;
750 
751 	return config3 & MIPS_CONF_M;
752 }
753 
754 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
755 {
756 	unsigned int config4;
757 	unsigned int newcf4;
758 	unsigned int mmuextdef;
759 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
760 	unsigned long asid_mask;
761 
762 	config4 = read_c0_config4();
763 
764 	if (cpu_has_tlb) {
765 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
766 			c->options |= MIPS_CPU_TLBINV;
767 
768 		/*
769 		 * R6 has dropped the MMUExtDef field from config4.
770 		 * On R6 the fields always describe the FTLB, and only if it is
771 		 * present according to Config.MT.
772 		 */
773 		if (!cpu_has_mips_r6)
774 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
775 		else if (cpu_has_ftlb)
776 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
777 		else
778 			mmuextdef = 0;
779 
780 		switch (mmuextdef) {
781 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
782 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
783 			c->tlbsizevtlb = c->tlbsize;
784 			break;
785 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
786 			c->tlbsizevtlb +=
787 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
788 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
789 			c->tlbsize = c->tlbsizevtlb;
790 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
791 			/* fall through */
792 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
793 			if (mips_ftlb_disabled)
794 				break;
795 			newcf4 = (config4 & ~ftlb_page) |
796 				(page_size_ftlb(mmuextdef) <<
797 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
798 			write_c0_config4(newcf4);
799 			back_to_back_c0_hazard();
800 			config4 = read_c0_config4();
801 			if (config4 != newcf4) {
802 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
803 				       PAGE_SIZE, config4);
804 				/* Switch FTLB off */
805 				set_ftlb_enable(c, 0);
806 				mips_ftlb_disabled = 1;
807 				break;
808 			}
809 			c->tlbsizeftlbsets = 1 <<
810 				((config4 & MIPS_CONF4_FTLBSETS) >>
811 				 MIPS_CONF4_FTLBSETS_SHIFT);
812 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
813 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
814 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
815 			mips_has_ftlb_configured = 1;
816 			break;
817 		}
818 	}
819 
820 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
821 				>> MIPS_CONF4_KSCREXIST_SHIFT;
822 
823 	asid_mask = MIPS_ENTRYHI_ASID;
824 	if (config4 & MIPS_CONF4_AE)
825 		asid_mask |= MIPS_ENTRYHI_ASIDX;
826 	set_cpu_asid_mask(c, asid_mask);
827 
828 	/*
829 	 * Warn if the computed ASID mask doesn't match the mask the kernel
830 	 * is built for. This may indicate either a serious problem or an
831 	 * easy optimisation opportunity, but either way should be addressed.
832 	 */
833 	WARN_ON(asid_mask != cpu_asid_mask(c));
834 
835 	return config4 & MIPS_CONF_M;
836 }
837 
838 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
839 {
840 	unsigned int config5;
841 
842 	config5 = read_c0_config5();
843 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
844 	write_c0_config5(config5);
845 
846 	if (config5 & MIPS_CONF5_EVA)
847 		c->options |= MIPS_CPU_EVA;
848 	if (config5 & MIPS_CONF5_MRP)
849 		c->options |= MIPS_CPU_MAAR;
850 	if (config5 & MIPS_CONF5_LLB)
851 		c->options |= MIPS_CPU_RW_LLB;
852 	if (config5 & MIPS_CONF5_MVH)
853 		c->options |= MIPS_CPU_MVH;
854 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
855 		c->options |= MIPS_CPU_VP;
856 	if (config5 & MIPS_CONF5_CA2)
857 		c->ases |= MIPS_ASE_MIPS16E2;
858 
859 	if (config5 & MIPS_CONF5_CRCP)
860 		elf_hwcap |= HWCAP_MIPS_CRC32;
861 
862 	return config5 & MIPS_CONF_M;
863 }
864 
865 static void decode_configs(struct cpuinfo_mips *c)
866 {
867 	int ok;
868 
869 	/* MIPS32 or MIPS64 compliant CPU.  */
870 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
871 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
872 
873 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
874 
875 	/* Enable FTLB if present and not disabled */
876 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
877 
878 	ok = decode_config0(c);			/* Read Config registers.  */
879 	BUG_ON(!ok);				/* Arch spec violation!	 */
880 	if (ok)
881 		ok = decode_config1(c);
882 	if (ok)
883 		ok = decode_config2(c);
884 	if (ok)
885 		ok = decode_config3(c);
886 	if (ok)
887 		ok = decode_config4(c);
888 	if (ok)
889 		ok = decode_config5(c);
890 
891 	/* Probe the EBase.WG bit */
892 	if (cpu_has_mips_r2_r6) {
893 		u64 ebase;
894 		unsigned int status;
895 
896 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
897 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
898 					 : (s32)read_c0_ebase();
899 		if (ebase & MIPS_EBASE_WG) {
900 			/* WG bit already set, we can avoid the clumsy probe */
901 			c->options |= MIPS_CPU_EBASE_WG;
902 		} else {
903 			/* Its UNDEFINED to change EBase while BEV=0 */
904 			status = read_c0_status();
905 			write_c0_status(status | ST0_BEV);
906 			irq_enable_hazard();
907 			/*
908 			 * On pre-r6 cores, this may well clobber the upper bits
909 			 * of EBase. This is hard to avoid without potentially
910 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
911 			 */
912 			if (cpu_has_mips64r6)
913 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
914 			else
915 				write_c0_ebase(ebase | MIPS_EBASE_WG);
916 			back_to_back_c0_hazard();
917 			/* Restore BEV */
918 			write_c0_status(status);
919 			if (read_c0_ebase() & MIPS_EBASE_WG) {
920 				c->options |= MIPS_CPU_EBASE_WG;
921 				write_c0_ebase(ebase);
922 			}
923 		}
924 	}
925 
926 	/* configure the FTLB write probability */
927 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
928 
929 	mips_probe_watch_registers(c);
930 
931 #ifndef CONFIG_MIPS_CPS
932 	if (cpu_has_mips_r2_r6) {
933 		unsigned int core;
934 
935 		core = get_ebase_cpunum();
936 		if (cpu_has_mipsmt)
937 			core >>= fls(core_nvpes()) - 1;
938 		cpu_set_core(c, core);
939 	}
940 #endif
941 }
942 
943 /*
944  * Probe for certain guest capabilities by writing config bits and reading back.
945  * Finally write back the original value.
946  */
947 #define probe_gc0_config(name, maxconf, bits)				\
948 do {									\
949 	unsigned int tmp;						\
950 	tmp = read_gc0_##name();					\
951 	write_gc0_##name(tmp | (bits));					\
952 	back_to_back_c0_hazard();					\
953 	maxconf = read_gc0_##name();					\
954 	write_gc0_##name(tmp);						\
955 } while (0)
956 
957 /*
958  * Probe for dynamic guest capabilities by changing certain config bits and
959  * reading back to see if they change. Finally write back the original value.
960  */
961 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
962 do {									\
963 	maxconf = read_gc0_##name();					\
964 	write_gc0_##name(maxconf ^ (bits));				\
965 	back_to_back_c0_hazard();					\
966 	dynconf = maxconf ^ read_gc0_##name();				\
967 	write_gc0_##name(maxconf);					\
968 	maxconf |= dynconf;						\
969 } while (0)
970 
971 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
972 {
973 	unsigned int config0;
974 
975 	probe_gc0_config(config, config0, MIPS_CONF_M);
976 
977 	if (config0 & MIPS_CONF_M)
978 		c->guest.conf |= BIT(1);
979 	return config0 & MIPS_CONF_M;
980 }
981 
982 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
983 {
984 	unsigned int config1, config1_dyn;
985 
986 	probe_gc0_config_dyn(config1, config1, config1_dyn,
987 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
988 			     MIPS_CONF1_FP);
989 
990 	if (config1 & MIPS_CONF1_FP)
991 		c->guest.options |= MIPS_CPU_FPU;
992 	if (config1_dyn & MIPS_CONF1_FP)
993 		c->guest.options_dyn |= MIPS_CPU_FPU;
994 
995 	if (config1 & MIPS_CONF1_WR)
996 		c->guest.options |= MIPS_CPU_WATCH;
997 	if (config1_dyn & MIPS_CONF1_WR)
998 		c->guest.options_dyn |= MIPS_CPU_WATCH;
999 
1000 	if (config1 & MIPS_CONF1_PC)
1001 		c->guest.options |= MIPS_CPU_PERF;
1002 	if (config1_dyn & MIPS_CONF1_PC)
1003 		c->guest.options_dyn |= MIPS_CPU_PERF;
1004 
1005 	if (config1 & MIPS_CONF_M)
1006 		c->guest.conf |= BIT(2);
1007 	return config1 & MIPS_CONF_M;
1008 }
1009 
1010 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
1011 {
1012 	unsigned int config2;
1013 
1014 	probe_gc0_config(config2, config2, MIPS_CONF_M);
1015 
1016 	if (config2 & MIPS_CONF_M)
1017 		c->guest.conf |= BIT(3);
1018 	return config2 & MIPS_CONF_M;
1019 }
1020 
1021 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
1022 {
1023 	unsigned int config3, config3_dyn;
1024 
1025 	probe_gc0_config_dyn(config3, config3, config3_dyn,
1026 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
1027 			     MIPS_CONF3_CTXTC);
1028 
1029 	if (config3 & MIPS_CONF3_CTXTC)
1030 		c->guest.options |= MIPS_CPU_CTXTC;
1031 	if (config3_dyn & MIPS_CONF3_CTXTC)
1032 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
1033 
1034 	if (config3 & MIPS_CONF3_PW)
1035 		c->guest.options |= MIPS_CPU_HTW;
1036 
1037 	if (config3 & MIPS_CONF3_ULRI)
1038 		c->guest.options |= MIPS_CPU_ULRI;
1039 
1040 	if (config3 & MIPS_CONF3_SC)
1041 		c->guest.options |= MIPS_CPU_SEGMENTS;
1042 
1043 	if (config3 & MIPS_CONF3_BI)
1044 		c->guest.options |= MIPS_CPU_BADINSTR;
1045 	if (config3 & MIPS_CONF3_BP)
1046 		c->guest.options |= MIPS_CPU_BADINSTRP;
1047 
1048 	if (config3 & MIPS_CONF3_MSA)
1049 		c->guest.ases |= MIPS_ASE_MSA;
1050 	if (config3_dyn & MIPS_CONF3_MSA)
1051 		c->guest.ases_dyn |= MIPS_ASE_MSA;
1052 
1053 	if (config3 & MIPS_CONF_M)
1054 		c->guest.conf |= BIT(4);
1055 	return config3 & MIPS_CONF_M;
1056 }
1057 
1058 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
1059 {
1060 	unsigned int config4;
1061 
1062 	probe_gc0_config(config4, config4,
1063 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
1064 
1065 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
1066 				>> MIPS_CONF4_KSCREXIST_SHIFT;
1067 
1068 	if (config4 & MIPS_CONF_M)
1069 		c->guest.conf |= BIT(5);
1070 	return config4 & MIPS_CONF_M;
1071 }
1072 
1073 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
1074 {
1075 	unsigned int config5, config5_dyn;
1076 
1077 	probe_gc0_config_dyn(config5, config5, config5_dyn,
1078 			 MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
1079 
1080 	if (config5 & MIPS_CONF5_MRP)
1081 		c->guest.options |= MIPS_CPU_MAAR;
1082 	if (config5_dyn & MIPS_CONF5_MRP)
1083 		c->guest.options_dyn |= MIPS_CPU_MAAR;
1084 
1085 	if (config5 & MIPS_CONF5_LLB)
1086 		c->guest.options |= MIPS_CPU_RW_LLB;
1087 
1088 	if (config5 & MIPS_CONF5_MVH)
1089 		c->guest.options |= MIPS_CPU_MVH;
1090 
1091 	if (config5 & MIPS_CONF_M)
1092 		c->guest.conf |= BIT(6);
1093 	return config5 & MIPS_CONF_M;
1094 }
1095 
1096 static inline void decode_guest_configs(struct cpuinfo_mips *c)
1097 {
1098 	unsigned int ok;
1099 
1100 	ok = decode_guest_config0(c);
1101 	if (ok)
1102 		ok = decode_guest_config1(c);
1103 	if (ok)
1104 		ok = decode_guest_config2(c);
1105 	if (ok)
1106 		ok = decode_guest_config3(c);
1107 	if (ok)
1108 		ok = decode_guest_config4(c);
1109 	if (ok)
1110 		decode_guest_config5(c);
1111 }
1112 
1113 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
1114 {
1115 	unsigned int guestctl0, temp;
1116 
1117 	guestctl0 = read_c0_guestctl0();
1118 
1119 	if (guestctl0 & MIPS_GCTL0_G0E)
1120 		c->options |= MIPS_CPU_GUESTCTL0EXT;
1121 	if (guestctl0 & MIPS_GCTL0_G1)
1122 		c->options |= MIPS_CPU_GUESTCTL1;
1123 	if (guestctl0 & MIPS_GCTL0_G2)
1124 		c->options |= MIPS_CPU_GUESTCTL2;
1125 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
1126 		c->options |= MIPS_CPU_GUESTID;
1127 
1128 		/*
1129 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
1130 		 * first, otherwise all data accesses will be fully virtualised
1131 		 * as if they were performed by guest mode.
1132 		 */
1133 		write_c0_guestctl1(0);
1134 		tlbw_use_hazard();
1135 
1136 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
1137 		back_to_back_c0_hazard();
1138 		temp = read_c0_guestctl0();
1139 
1140 		if (temp & MIPS_GCTL0_DRG) {
1141 			write_c0_guestctl0(guestctl0);
1142 			c->options |= MIPS_CPU_DRG;
1143 		}
1144 	}
1145 }
1146 
1147 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1148 {
1149 	if (cpu_has_guestid) {
1150 		/* determine the number of bits of GuestID available */
1151 		write_c0_guestctl1(MIPS_GCTL1_ID);
1152 		back_to_back_c0_hazard();
1153 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1154 						>> MIPS_GCTL1_ID_SHIFT;
1155 		write_c0_guestctl1(0);
1156 	}
1157 }
1158 
1159 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1160 {
1161 	/* determine the number of bits of GTOffset available */
1162 	write_c0_gtoffset(0xffffffff);
1163 	back_to_back_c0_hazard();
1164 	c->gtoffset_mask = read_c0_gtoffset();
1165 	write_c0_gtoffset(0);
1166 }
1167 
1168 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1169 {
1170 	cpu_probe_guestctl0(c);
1171 	if (cpu_has_guestctl1)
1172 		cpu_probe_guestctl1(c);
1173 
1174 	cpu_probe_gtoffset(c);
1175 
1176 	decode_guest_configs(c);
1177 }
1178 
1179 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1180 		| MIPS_CPU_COUNTER)
1181 
1182 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1183 {
1184 	switch (c->processor_id & PRID_IMP_MASK) {
1185 	case PRID_IMP_R2000:
1186 		c->cputype = CPU_R2000;
1187 		__cpu_name[cpu] = "R2000";
1188 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1189 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1190 			     MIPS_CPU_NOFPUEX;
1191 		if (__cpu_has_fpu())
1192 			c->options |= MIPS_CPU_FPU;
1193 		c->tlbsize = 64;
1194 		break;
1195 	case PRID_IMP_R3000:
1196 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1197 			if (cpu_has_confreg()) {
1198 				c->cputype = CPU_R3081E;
1199 				__cpu_name[cpu] = "R3081";
1200 			} else {
1201 				c->cputype = CPU_R3000A;
1202 				__cpu_name[cpu] = "R3000A";
1203 			}
1204 		} else {
1205 			c->cputype = CPU_R3000;
1206 			__cpu_name[cpu] = "R3000";
1207 		}
1208 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1209 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1210 			     MIPS_CPU_NOFPUEX;
1211 		if (__cpu_has_fpu())
1212 			c->options |= MIPS_CPU_FPU;
1213 		c->tlbsize = 64;
1214 		break;
1215 	case PRID_IMP_R4000:
1216 		if (read_c0_config() & CONF_SC) {
1217 			if ((c->processor_id & PRID_REV_MASK) >=
1218 			    PRID_REV_R4400) {
1219 				c->cputype = CPU_R4400PC;
1220 				__cpu_name[cpu] = "R4400PC";
1221 			} else {
1222 				c->cputype = CPU_R4000PC;
1223 				__cpu_name[cpu] = "R4000PC";
1224 			}
1225 		} else {
1226 			int cca = read_c0_config() & CONF_CM_CMASK;
1227 			int mc;
1228 
1229 			/*
1230 			 * SC and MC versions can't be reliably told apart,
1231 			 * but only the latter support coherent caching
1232 			 * modes so assume the firmware has set the KSEG0
1233 			 * coherency attribute reasonably (if uncached, we
1234 			 * assume SC).
1235 			 */
1236 			switch (cca) {
1237 			case CONF_CM_CACHABLE_CE:
1238 			case CONF_CM_CACHABLE_COW:
1239 			case CONF_CM_CACHABLE_CUW:
1240 				mc = 1;
1241 				break;
1242 			default:
1243 				mc = 0;
1244 				break;
1245 			}
1246 			if ((c->processor_id & PRID_REV_MASK) >=
1247 			    PRID_REV_R4400) {
1248 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1249 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1250 			} else {
1251 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1252 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1253 			}
1254 		}
1255 
1256 		set_isa(c, MIPS_CPU_ISA_III);
1257 		c->fpu_msk31 |= FPU_CSR_CONDX;
1258 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1259 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1260 			     MIPS_CPU_LLSC;
1261 		c->tlbsize = 48;
1262 		break;
1263 	case PRID_IMP_VR41XX:
1264 		set_isa(c, MIPS_CPU_ISA_III);
1265 		c->fpu_msk31 |= FPU_CSR_CONDX;
1266 		c->options = R4K_OPTS;
1267 		c->tlbsize = 32;
1268 		switch (c->processor_id & 0xf0) {
1269 		case PRID_REV_VR4111:
1270 			c->cputype = CPU_VR4111;
1271 			__cpu_name[cpu] = "NEC VR4111";
1272 			break;
1273 		case PRID_REV_VR4121:
1274 			c->cputype = CPU_VR4121;
1275 			__cpu_name[cpu] = "NEC VR4121";
1276 			break;
1277 		case PRID_REV_VR4122:
1278 			if ((c->processor_id & 0xf) < 0x3) {
1279 				c->cputype = CPU_VR4122;
1280 				__cpu_name[cpu] = "NEC VR4122";
1281 			} else {
1282 				c->cputype = CPU_VR4181A;
1283 				__cpu_name[cpu] = "NEC VR4181A";
1284 			}
1285 			break;
1286 		case PRID_REV_VR4130:
1287 			if ((c->processor_id & 0xf) < 0x4) {
1288 				c->cputype = CPU_VR4131;
1289 				__cpu_name[cpu] = "NEC VR4131";
1290 			} else {
1291 				c->cputype = CPU_VR4133;
1292 				c->options |= MIPS_CPU_LLSC;
1293 				__cpu_name[cpu] = "NEC VR4133";
1294 			}
1295 			break;
1296 		default:
1297 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1298 			c->cputype = CPU_VR41XX;
1299 			__cpu_name[cpu] = "NEC Vr41xx";
1300 			break;
1301 		}
1302 		break;
1303 	case PRID_IMP_R4300:
1304 		c->cputype = CPU_R4300;
1305 		__cpu_name[cpu] = "R4300";
1306 		set_isa(c, MIPS_CPU_ISA_III);
1307 		c->fpu_msk31 |= FPU_CSR_CONDX;
1308 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1309 			     MIPS_CPU_LLSC;
1310 		c->tlbsize = 32;
1311 		break;
1312 	case PRID_IMP_R4600:
1313 		c->cputype = CPU_R4600;
1314 		__cpu_name[cpu] = "R4600";
1315 		set_isa(c, MIPS_CPU_ISA_III);
1316 		c->fpu_msk31 |= FPU_CSR_CONDX;
1317 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1318 			     MIPS_CPU_LLSC;
1319 		c->tlbsize = 48;
1320 		break;
1321 	#if 0
1322 	case PRID_IMP_R4650:
1323 		/*
1324 		 * This processor doesn't have an MMU, so it's not
1325 		 * "real easy" to run Linux on it. It is left purely
1326 		 * for documentation.  Commented out because it shares
1327 		 * it's c0_prid id number with the TX3900.
1328 		 */
1329 		c->cputype = CPU_R4650;
1330 		__cpu_name[cpu] = "R4650";
1331 		set_isa(c, MIPS_CPU_ISA_III);
1332 		c->fpu_msk31 |= FPU_CSR_CONDX;
1333 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1334 		c->tlbsize = 48;
1335 		break;
1336 	#endif
1337 	case PRID_IMP_TX39:
1338 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1339 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1340 
1341 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1342 			c->cputype = CPU_TX3927;
1343 			__cpu_name[cpu] = "TX3927";
1344 			c->tlbsize = 64;
1345 		} else {
1346 			switch (c->processor_id & PRID_REV_MASK) {
1347 			case PRID_REV_TX3912:
1348 				c->cputype = CPU_TX3912;
1349 				__cpu_name[cpu] = "TX3912";
1350 				c->tlbsize = 32;
1351 				break;
1352 			case PRID_REV_TX3922:
1353 				c->cputype = CPU_TX3922;
1354 				__cpu_name[cpu] = "TX3922";
1355 				c->tlbsize = 64;
1356 				break;
1357 			}
1358 		}
1359 		break;
1360 	case PRID_IMP_R4700:
1361 		c->cputype = CPU_R4700;
1362 		__cpu_name[cpu] = "R4700";
1363 		set_isa(c, MIPS_CPU_ISA_III);
1364 		c->fpu_msk31 |= FPU_CSR_CONDX;
1365 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1366 			     MIPS_CPU_LLSC;
1367 		c->tlbsize = 48;
1368 		break;
1369 	case PRID_IMP_TX49:
1370 		c->cputype = CPU_TX49XX;
1371 		__cpu_name[cpu] = "R49XX";
1372 		set_isa(c, MIPS_CPU_ISA_III);
1373 		c->fpu_msk31 |= FPU_CSR_CONDX;
1374 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1375 		if (!(c->processor_id & 0x08))
1376 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1377 		c->tlbsize = 48;
1378 		break;
1379 	case PRID_IMP_R5000:
1380 		c->cputype = CPU_R5000;
1381 		__cpu_name[cpu] = "R5000";
1382 		set_isa(c, MIPS_CPU_ISA_IV);
1383 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1384 			     MIPS_CPU_LLSC;
1385 		c->tlbsize = 48;
1386 		break;
1387 	case PRID_IMP_R5432:
1388 		c->cputype = CPU_R5432;
1389 		__cpu_name[cpu] = "R5432";
1390 		set_isa(c, MIPS_CPU_ISA_IV);
1391 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1392 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1393 		c->tlbsize = 48;
1394 		break;
1395 	case PRID_IMP_R5500:
1396 		c->cputype = CPU_R5500;
1397 		__cpu_name[cpu] = "R5500";
1398 		set_isa(c, MIPS_CPU_ISA_IV);
1399 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1400 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1401 		c->tlbsize = 48;
1402 		break;
1403 	case PRID_IMP_NEVADA:
1404 		c->cputype = CPU_NEVADA;
1405 		__cpu_name[cpu] = "Nevada";
1406 		set_isa(c, MIPS_CPU_ISA_IV);
1407 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1408 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1409 		c->tlbsize = 48;
1410 		break;
1411 	case PRID_IMP_RM7000:
1412 		c->cputype = CPU_RM7000;
1413 		__cpu_name[cpu] = "RM7000";
1414 		set_isa(c, MIPS_CPU_ISA_IV);
1415 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1416 			     MIPS_CPU_LLSC;
1417 		/*
1418 		 * Undocumented RM7000:	 Bit 29 in the info register of
1419 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1420 		 * entries.
1421 		 *
1422 		 * 29	   1 =>	   64 entry JTLB
1423 		 *	   0 =>	   48 entry JTLB
1424 		 */
1425 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1426 		break;
1427 	case PRID_IMP_R8000:
1428 		c->cputype = CPU_R8000;
1429 		__cpu_name[cpu] = "RM8000";
1430 		set_isa(c, MIPS_CPU_ISA_IV);
1431 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
1432 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1433 			     MIPS_CPU_LLSC;
1434 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
1435 		break;
1436 	case PRID_IMP_R10000:
1437 		c->cputype = CPU_R10000;
1438 		__cpu_name[cpu] = "R10000";
1439 		set_isa(c, MIPS_CPU_ISA_IV);
1440 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1441 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1442 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1443 			     MIPS_CPU_LLSC;
1444 		c->tlbsize = 64;
1445 		break;
1446 	case PRID_IMP_R12000:
1447 		c->cputype = CPU_R12000;
1448 		__cpu_name[cpu] = "R12000";
1449 		set_isa(c, MIPS_CPU_ISA_IV);
1450 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1451 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1452 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1453 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1454 		c->tlbsize = 64;
1455 		break;
1456 	case PRID_IMP_R14000:
1457 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1458 			c->cputype = CPU_R16000;
1459 			__cpu_name[cpu] = "R16000";
1460 		} else {
1461 			c->cputype = CPU_R14000;
1462 			__cpu_name[cpu] = "R14000";
1463 		}
1464 		set_isa(c, MIPS_CPU_ISA_IV);
1465 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1466 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1467 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1468 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1469 		c->tlbsize = 64;
1470 		break;
1471 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1472 		switch (c->processor_id & PRID_REV_MASK) {
1473 		case PRID_REV_LOONGSON2E:
1474 			c->cputype = CPU_LOONGSON2;
1475 			__cpu_name[cpu] = "ICT Loongson-2";
1476 			set_elf_platform(cpu, "loongson2e");
1477 			set_isa(c, MIPS_CPU_ISA_III);
1478 			c->fpu_msk31 |= FPU_CSR_CONDX;
1479 			break;
1480 		case PRID_REV_LOONGSON2F:
1481 			c->cputype = CPU_LOONGSON2;
1482 			__cpu_name[cpu] = "ICT Loongson-2";
1483 			set_elf_platform(cpu, "loongson2f");
1484 			set_isa(c, MIPS_CPU_ISA_III);
1485 			c->fpu_msk31 |= FPU_CSR_CONDX;
1486 			break;
1487 		case PRID_REV_LOONGSON3A_R1:
1488 			c->cputype = CPU_LOONGSON3;
1489 			__cpu_name[cpu] = "ICT Loongson-3";
1490 			set_elf_platform(cpu, "loongson3a");
1491 			set_isa(c, MIPS_CPU_ISA_M64R1);
1492 			break;
1493 		case PRID_REV_LOONGSON3B_R1:
1494 		case PRID_REV_LOONGSON3B_R2:
1495 			c->cputype = CPU_LOONGSON3;
1496 			__cpu_name[cpu] = "ICT Loongson-3";
1497 			set_elf_platform(cpu, "loongson3b");
1498 			set_isa(c, MIPS_CPU_ISA_M64R1);
1499 			break;
1500 		}
1501 
1502 		c->options = R4K_OPTS |
1503 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1504 			     MIPS_CPU_32FPR;
1505 		c->tlbsize = 64;
1506 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1507 		break;
1508 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1509 		decode_configs(c);
1510 
1511 		c->cputype = CPU_LOONGSON1;
1512 
1513 		switch (c->processor_id & PRID_REV_MASK) {
1514 		case PRID_REV_LOONGSON1B:
1515 			__cpu_name[cpu] = "Loongson 1B";
1516 			break;
1517 		}
1518 
1519 		break;
1520 	}
1521 }
1522 
1523 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1524 {
1525 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1526 	switch (c->processor_id & PRID_IMP_MASK) {
1527 	case PRID_IMP_QEMU_GENERIC:
1528 		c->writecombine = _CACHE_UNCACHED;
1529 		c->cputype = CPU_QEMU_GENERIC;
1530 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1531 		break;
1532 	case PRID_IMP_4KC:
1533 		c->cputype = CPU_4KC;
1534 		c->writecombine = _CACHE_UNCACHED;
1535 		__cpu_name[cpu] = "MIPS 4Kc";
1536 		break;
1537 	case PRID_IMP_4KEC:
1538 	case PRID_IMP_4KECR2:
1539 		c->cputype = CPU_4KEC;
1540 		c->writecombine = _CACHE_UNCACHED;
1541 		__cpu_name[cpu] = "MIPS 4KEc";
1542 		break;
1543 	case PRID_IMP_4KSC:
1544 	case PRID_IMP_4KSD:
1545 		c->cputype = CPU_4KSC;
1546 		c->writecombine = _CACHE_UNCACHED;
1547 		__cpu_name[cpu] = "MIPS 4KSc";
1548 		break;
1549 	case PRID_IMP_5KC:
1550 		c->cputype = CPU_5KC;
1551 		c->writecombine = _CACHE_UNCACHED;
1552 		__cpu_name[cpu] = "MIPS 5Kc";
1553 		break;
1554 	case PRID_IMP_5KE:
1555 		c->cputype = CPU_5KE;
1556 		c->writecombine = _CACHE_UNCACHED;
1557 		__cpu_name[cpu] = "MIPS 5KE";
1558 		break;
1559 	case PRID_IMP_20KC:
1560 		c->cputype = CPU_20KC;
1561 		c->writecombine = _CACHE_UNCACHED;
1562 		__cpu_name[cpu] = "MIPS 20Kc";
1563 		break;
1564 	case PRID_IMP_24K:
1565 		c->cputype = CPU_24K;
1566 		c->writecombine = _CACHE_UNCACHED;
1567 		__cpu_name[cpu] = "MIPS 24Kc";
1568 		break;
1569 	case PRID_IMP_24KE:
1570 		c->cputype = CPU_24K;
1571 		c->writecombine = _CACHE_UNCACHED;
1572 		__cpu_name[cpu] = "MIPS 24KEc";
1573 		break;
1574 	case PRID_IMP_25KF:
1575 		c->cputype = CPU_25KF;
1576 		c->writecombine = _CACHE_UNCACHED;
1577 		__cpu_name[cpu] = "MIPS 25Kc";
1578 		break;
1579 	case PRID_IMP_34K:
1580 		c->cputype = CPU_34K;
1581 		c->writecombine = _CACHE_UNCACHED;
1582 		__cpu_name[cpu] = "MIPS 34Kc";
1583 		cpu_set_mt_per_tc_perf(c);
1584 		break;
1585 	case PRID_IMP_74K:
1586 		c->cputype = CPU_74K;
1587 		c->writecombine = _CACHE_UNCACHED;
1588 		__cpu_name[cpu] = "MIPS 74Kc";
1589 		break;
1590 	case PRID_IMP_M14KC:
1591 		c->cputype = CPU_M14KC;
1592 		c->writecombine = _CACHE_UNCACHED;
1593 		__cpu_name[cpu] = "MIPS M14Kc";
1594 		break;
1595 	case PRID_IMP_M14KEC:
1596 		c->cputype = CPU_M14KEC;
1597 		c->writecombine = _CACHE_UNCACHED;
1598 		__cpu_name[cpu] = "MIPS M14KEc";
1599 		break;
1600 	case PRID_IMP_1004K:
1601 		c->cputype = CPU_1004K;
1602 		c->writecombine = _CACHE_UNCACHED;
1603 		__cpu_name[cpu] = "MIPS 1004Kc";
1604 		cpu_set_mt_per_tc_perf(c);
1605 		break;
1606 	case PRID_IMP_1074K:
1607 		c->cputype = CPU_1074K;
1608 		c->writecombine = _CACHE_UNCACHED;
1609 		__cpu_name[cpu] = "MIPS 1074Kc";
1610 		break;
1611 	case PRID_IMP_INTERAPTIV_UP:
1612 		c->cputype = CPU_INTERAPTIV;
1613 		__cpu_name[cpu] = "MIPS interAptiv";
1614 		cpu_set_mt_per_tc_perf(c);
1615 		break;
1616 	case PRID_IMP_INTERAPTIV_MP:
1617 		c->cputype = CPU_INTERAPTIV;
1618 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1619 		cpu_set_mt_per_tc_perf(c);
1620 		break;
1621 	case PRID_IMP_PROAPTIV_UP:
1622 		c->cputype = CPU_PROAPTIV;
1623 		__cpu_name[cpu] = "MIPS proAptiv";
1624 		break;
1625 	case PRID_IMP_PROAPTIV_MP:
1626 		c->cputype = CPU_PROAPTIV;
1627 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1628 		break;
1629 	case PRID_IMP_P5600:
1630 		c->cputype = CPU_P5600;
1631 		__cpu_name[cpu] = "MIPS P5600";
1632 		break;
1633 	case PRID_IMP_P6600:
1634 		c->cputype = CPU_P6600;
1635 		__cpu_name[cpu] = "MIPS P6600";
1636 		break;
1637 	case PRID_IMP_I6400:
1638 		c->cputype = CPU_I6400;
1639 		__cpu_name[cpu] = "MIPS I6400";
1640 		break;
1641 	case PRID_IMP_I6500:
1642 		c->cputype = CPU_I6500;
1643 		__cpu_name[cpu] = "MIPS I6500";
1644 		break;
1645 	case PRID_IMP_M5150:
1646 		c->cputype = CPU_M5150;
1647 		__cpu_name[cpu] = "MIPS M5150";
1648 		break;
1649 	case PRID_IMP_M6250:
1650 		c->cputype = CPU_M6250;
1651 		__cpu_name[cpu] = "MIPS M6250";
1652 		break;
1653 	}
1654 
1655 	decode_configs(c);
1656 
1657 	spram_config();
1658 
1659 	switch (__get_cpu_type(c->cputype)) {
1660 	case CPU_I6500:
1661 		c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
1662 		/* fall-through */
1663 	case CPU_I6400:
1664 		c->options |= MIPS_CPU_SHARED_FTLB_RAM;
1665 		/* fall-through */
1666 	default:
1667 		break;
1668 	}
1669 }
1670 
1671 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1672 {
1673 	decode_configs(c);
1674 	switch (c->processor_id & PRID_IMP_MASK) {
1675 	case PRID_IMP_AU1_REV1:
1676 	case PRID_IMP_AU1_REV2:
1677 		c->cputype = CPU_ALCHEMY;
1678 		switch ((c->processor_id >> 24) & 0xff) {
1679 		case 0:
1680 			__cpu_name[cpu] = "Au1000";
1681 			break;
1682 		case 1:
1683 			__cpu_name[cpu] = "Au1500";
1684 			break;
1685 		case 2:
1686 			__cpu_name[cpu] = "Au1100";
1687 			break;
1688 		case 3:
1689 			__cpu_name[cpu] = "Au1550";
1690 			break;
1691 		case 4:
1692 			__cpu_name[cpu] = "Au1200";
1693 			if ((c->processor_id & PRID_REV_MASK) == 2)
1694 				__cpu_name[cpu] = "Au1250";
1695 			break;
1696 		case 5:
1697 			__cpu_name[cpu] = "Au1210";
1698 			break;
1699 		default:
1700 			__cpu_name[cpu] = "Au1xxx";
1701 			break;
1702 		}
1703 		break;
1704 	}
1705 }
1706 
1707 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1708 {
1709 	decode_configs(c);
1710 
1711 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1712 	switch (c->processor_id & PRID_IMP_MASK) {
1713 	case PRID_IMP_SB1:
1714 		c->cputype = CPU_SB1;
1715 		__cpu_name[cpu] = "SiByte SB1";
1716 		/* FPU in pass1 is known to have issues. */
1717 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1718 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1719 		break;
1720 	case PRID_IMP_SB1A:
1721 		c->cputype = CPU_SB1A;
1722 		__cpu_name[cpu] = "SiByte SB1A";
1723 		break;
1724 	}
1725 }
1726 
1727 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1728 {
1729 	decode_configs(c);
1730 	switch (c->processor_id & PRID_IMP_MASK) {
1731 	case PRID_IMP_SR71000:
1732 		c->cputype = CPU_SR71000;
1733 		__cpu_name[cpu] = "Sandcraft SR71000";
1734 		c->scache.ways = 8;
1735 		c->tlbsize = 64;
1736 		break;
1737 	}
1738 }
1739 
1740 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1741 {
1742 	decode_configs(c);
1743 	switch (c->processor_id & PRID_IMP_MASK) {
1744 	case PRID_IMP_PR4450:
1745 		c->cputype = CPU_PR4450;
1746 		__cpu_name[cpu] = "Philips PR4450";
1747 		set_isa(c, MIPS_CPU_ISA_M32R1);
1748 		break;
1749 	}
1750 }
1751 
1752 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1753 {
1754 	decode_configs(c);
1755 	switch (c->processor_id & PRID_IMP_MASK) {
1756 	case PRID_IMP_BMIPS32_REV4:
1757 	case PRID_IMP_BMIPS32_REV8:
1758 		c->cputype = CPU_BMIPS32;
1759 		__cpu_name[cpu] = "Broadcom BMIPS32";
1760 		set_elf_platform(cpu, "bmips32");
1761 		break;
1762 	case PRID_IMP_BMIPS3300:
1763 	case PRID_IMP_BMIPS3300_ALT:
1764 	case PRID_IMP_BMIPS3300_BUG:
1765 		c->cputype = CPU_BMIPS3300;
1766 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1767 		set_elf_platform(cpu, "bmips3300");
1768 		break;
1769 	case PRID_IMP_BMIPS43XX: {
1770 		int rev = c->processor_id & PRID_REV_MASK;
1771 
1772 		if (rev >= PRID_REV_BMIPS4380_LO &&
1773 				rev <= PRID_REV_BMIPS4380_HI) {
1774 			c->cputype = CPU_BMIPS4380;
1775 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1776 			set_elf_platform(cpu, "bmips4380");
1777 			c->options |= MIPS_CPU_RIXI;
1778 		} else {
1779 			c->cputype = CPU_BMIPS4350;
1780 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1781 			set_elf_platform(cpu, "bmips4350");
1782 		}
1783 		break;
1784 	}
1785 	case PRID_IMP_BMIPS5000:
1786 	case PRID_IMP_BMIPS5200:
1787 		c->cputype = CPU_BMIPS5000;
1788 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1789 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1790 		else
1791 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1792 		set_elf_platform(cpu, "bmips5000");
1793 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1794 		break;
1795 	}
1796 }
1797 
1798 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1799 {
1800 	decode_configs(c);
1801 	switch (c->processor_id & PRID_IMP_MASK) {
1802 	case PRID_IMP_CAVIUM_CN38XX:
1803 	case PRID_IMP_CAVIUM_CN31XX:
1804 	case PRID_IMP_CAVIUM_CN30XX:
1805 		c->cputype = CPU_CAVIUM_OCTEON;
1806 		__cpu_name[cpu] = "Cavium Octeon";
1807 		goto platform;
1808 	case PRID_IMP_CAVIUM_CN58XX:
1809 	case PRID_IMP_CAVIUM_CN56XX:
1810 	case PRID_IMP_CAVIUM_CN50XX:
1811 	case PRID_IMP_CAVIUM_CN52XX:
1812 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1813 		__cpu_name[cpu] = "Cavium Octeon+";
1814 platform:
1815 		set_elf_platform(cpu, "octeon");
1816 		break;
1817 	case PRID_IMP_CAVIUM_CN61XX:
1818 	case PRID_IMP_CAVIUM_CN63XX:
1819 	case PRID_IMP_CAVIUM_CN66XX:
1820 	case PRID_IMP_CAVIUM_CN68XX:
1821 	case PRID_IMP_CAVIUM_CNF71XX:
1822 		c->cputype = CPU_CAVIUM_OCTEON2;
1823 		__cpu_name[cpu] = "Cavium Octeon II";
1824 		set_elf_platform(cpu, "octeon2");
1825 		break;
1826 	case PRID_IMP_CAVIUM_CN70XX:
1827 	case PRID_IMP_CAVIUM_CN73XX:
1828 	case PRID_IMP_CAVIUM_CNF75XX:
1829 	case PRID_IMP_CAVIUM_CN78XX:
1830 		c->cputype = CPU_CAVIUM_OCTEON3;
1831 		__cpu_name[cpu] = "Cavium Octeon III";
1832 		set_elf_platform(cpu, "octeon3");
1833 		break;
1834 	default:
1835 		printk(KERN_INFO "Unknown Octeon chip!\n");
1836 		c->cputype = CPU_UNKNOWN;
1837 		break;
1838 	}
1839 }
1840 
1841 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
1842 {
1843 	switch (c->processor_id & PRID_IMP_MASK) {
1844 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1845 		switch (c->processor_id & PRID_REV_MASK) {
1846 		case PRID_REV_LOONGSON3A_R2:
1847 			c->cputype = CPU_LOONGSON3;
1848 			__cpu_name[cpu] = "ICT Loongson-3";
1849 			set_elf_platform(cpu, "loongson3a");
1850 			set_isa(c, MIPS_CPU_ISA_M64R2);
1851 			break;
1852 		case PRID_REV_LOONGSON3A_R3:
1853 			c->cputype = CPU_LOONGSON3;
1854 			__cpu_name[cpu] = "ICT Loongson-3";
1855 			set_elf_platform(cpu, "loongson3a");
1856 			set_isa(c, MIPS_CPU_ISA_M64R2);
1857 			break;
1858 		}
1859 
1860 		decode_configs(c);
1861 		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
1862 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1863 		break;
1864 	default:
1865 		panic("Unknown Loongson Processor ID!");
1866 		break;
1867 	}
1868 }
1869 
1870 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1871 {
1872 	decode_configs(c);
1873 	/* JZRISC does not implement the CP0 counter. */
1874 	c->options &= ~MIPS_CPU_COUNTER;
1875 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
1876 	switch (c->processor_id & PRID_IMP_MASK) {
1877 	case PRID_IMP_JZRISC:
1878 		c->cputype = CPU_JZRISC;
1879 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1880 		__cpu_name[cpu] = "Ingenic JZRISC";
1881 		break;
1882 	default:
1883 		panic("Unknown Ingenic Processor ID!");
1884 		break;
1885 	}
1886 }
1887 
1888 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1889 {
1890 	decode_configs(c);
1891 
1892 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1893 		c->cputype = CPU_ALCHEMY;
1894 		__cpu_name[cpu] = "Au1300";
1895 		/* following stuff is not for Alchemy */
1896 		return;
1897 	}
1898 
1899 	c->options = (MIPS_CPU_TLB	 |
1900 			MIPS_CPU_4KEX	 |
1901 			MIPS_CPU_COUNTER |
1902 			MIPS_CPU_DIVEC	 |
1903 			MIPS_CPU_WATCH	 |
1904 			MIPS_CPU_EJTAG	 |
1905 			MIPS_CPU_LLSC);
1906 
1907 	switch (c->processor_id & PRID_IMP_MASK) {
1908 	case PRID_IMP_NETLOGIC_XLP2XX:
1909 	case PRID_IMP_NETLOGIC_XLP9XX:
1910 	case PRID_IMP_NETLOGIC_XLP5XX:
1911 		c->cputype = CPU_XLP;
1912 		__cpu_name[cpu] = "Broadcom XLPII";
1913 		break;
1914 
1915 	case PRID_IMP_NETLOGIC_XLP8XX:
1916 	case PRID_IMP_NETLOGIC_XLP3XX:
1917 		c->cputype = CPU_XLP;
1918 		__cpu_name[cpu] = "Netlogic XLP";
1919 		break;
1920 
1921 	case PRID_IMP_NETLOGIC_XLR732:
1922 	case PRID_IMP_NETLOGIC_XLR716:
1923 	case PRID_IMP_NETLOGIC_XLR532:
1924 	case PRID_IMP_NETLOGIC_XLR308:
1925 	case PRID_IMP_NETLOGIC_XLR532C:
1926 	case PRID_IMP_NETLOGIC_XLR516C:
1927 	case PRID_IMP_NETLOGIC_XLR508C:
1928 	case PRID_IMP_NETLOGIC_XLR308C:
1929 		c->cputype = CPU_XLR;
1930 		__cpu_name[cpu] = "Netlogic XLR";
1931 		break;
1932 
1933 	case PRID_IMP_NETLOGIC_XLS608:
1934 	case PRID_IMP_NETLOGIC_XLS408:
1935 	case PRID_IMP_NETLOGIC_XLS404:
1936 	case PRID_IMP_NETLOGIC_XLS208:
1937 	case PRID_IMP_NETLOGIC_XLS204:
1938 	case PRID_IMP_NETLOGIC_XLS108:
1939 	case PRID_IMP_NETLOGIC_XLS104:
1940 	case PRID_IMP_NETLOGIC_XLS616B:
1941 	case PRID_IMP_NETLOGIC_XLS608B:
1942 	case PRID_IMP_NETLOGIC_XLS416B:
1943 	case PRID_IMP_NETLOGIC_XLS412B:
1944 	case PRID_IMP_NETLOGIC_XLS408B:
1945 	case PRID_IMP_NETLOGIC_XLS404B:
1946 		c->cputype = CPU_XLR;
1947 		__cpu_name[cpu] = "Netlogic XLS";
1948 		break;
1949 
1950 	default:
1951 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1952 		       c->processor_id);
1953 		c->cputype = CPU_XLR;
1954 		break;
1955 	}
1956 
1957 	if (c->cputype == CPU_XLP) {
1958 		set_isa(c, MIPS_CPU_ISA_M64R2);
1959 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1960 		/* This will be updated again after all threads are woken up */
1961 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1962 	} else {
1963 		set_isa(c, MIPS_CPU_ISA_M64R1);
1964 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1965 	}
1966 	c->kscratch_mask = 0xf;
1967 }
1968 
1969 #ifdef CONFIG_64BIT
1970 /* For use by uaccess.h */
1971 u64 __ua_limit;
1972 EXPORT_SYMBOL(__ua_limit);
1973 #endif
1974 
1975 const char *__cpu_name[NR_CPUS];
1976 const char *__elf_platform;
1977 
1978 void cpu_probe(void)
1979 {
1980 	struct cpuinfo_mips *c = &current_cpu_data;
1981 	unsigned int cpu = smp_processor_id();
1982 
1983 	/*
1984 	 * Set a default elf platform, cpu probe may later
1985 	 * overwrite it with a more precise value
1986 	 */
1987 	set_elf_platform(cpu, "mips");
1988 
1989 	c->processor_id = PRID_IMP_UNKNOWN;
1990 	c->fpu_id	= FPIR_IMP_NONE;
1991 	c->cputype	= CPU_UNKNOWN;
1992 	c->writecombine = _CACHE_UNCACHED;
1993 
1994 	c->fpu_csr31	= FPU_CSR_RN;
1995 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
1996 
1997 	c->processor_id = read_c0_prid();
1998 	switch (c->processor_id & PRID_COMP_MASK) {
1999 	case PRID_COMP_LEGACY:
2000 		cpu_probe_legacy(c, cpu);
2001 		break;
2002 	case PRID_COMP_MIPS:
2003 		cpu_probe_mips(c, cpu);
2004 		break;
2005 	case PRID_COMP_ALCHEMY:
2006 		cpu_probe_alchemy(c, cpu);
2007 		break;
2008 	case PRID_COMP_SIBYTE:
2009 		cpu_probe_sibyte(c, cpu);
2010 		break;
2011 	case PRID_COMP_BROADCOM:
2012 		cpu_probe_broadcom(c, cpu);
2013 		break;
2014 	case PRID_COMP_SANDCRAFT:
2015 		cpu_probe_sandcraft(c, cpu);
2016 		break;
2017 	case PRID_COMP_NXP:
2018 		cpu_probe_nxp(c, cpu);
2019 		break;
2020 	case PRID_COMP_CAVIUM:
2021 		cpu_probe_cavium(c, cpu);
2022 		break;
2023 	case PRID_COMP_LOONGSON:
2024 		cpu_probe_loongson(c, cpu);
2025 		break;
2026 	case PRID_COMP_INGENIC_D0:
2027 	case PRID_COMP_INGENIC_D1:
2028 	case PRID_COMP_INGENIC_E1:
2029 		cpu_probe_ingenic(c, cpu);
2030 		break;
2031 	case PRID_COMP_NETLOGIC:
2032 		cpu_probe_netlogic(c, cpu);
2033 		break;
2034 	}
2035 
2036 	BUG_ON(!__cpu_name[cpu]);
2037 	BUG_ON(c->cputype == CPU_UNKNOWN);
2038 
2039 	/*
2040 	 * Platform code can force the cpu type to optimize code
2041 	 * generation. In that case be sure the cpu type is correctly
2042 	 * manually setup otherwise it could trigger some nasty bugs.
2043 	 */
2044 	BUG_ON(current_cpu_type() != c->cputype);
2045 
2046 	if (cpu_has_rixi) {
2047 		/* Enable the RIXI exceptions */
2048 		set_c0_pagegrain(PG_IEC);
2049 		back_to_back_c0_hazard();
2050 		/* Verify the IEC bit is set */
2051 		if (read_c0_pagegrain() & PG_IEC)
2052 			c->options |= MIPS_CPU_RIXIEX;
2053 	}
2054 
2055 	if (mips_fpu_disabled)
2056 		c->options &= ~MIPS_CPU_FPU;
2057 
2058 	if (mips_dsp_disabled)
2059 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2060 
2061 	if (mips_htw_disabled) {
2062 		c->options &= ~MIPS_CPU_HTW;
2063 		write_c0_pwctl(read_c0_pwctl() &
2064 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2065 	}
2066 
2067 	if (c->options & MIPS_CPU_FPU)
2068 		cpu_set_fpu_opts(c);
2069 	else
2070 		cpu_set_nofpu_opts(c);
2071 
2072 	if (cpu_has_bp_ghist)
2073 		write_c0_r10k_diag(read_c0_r10k_diag() |
2074 				   R10K_DIAG_E_GHIST);
2075 
2076 	if (cpu_has_mips_r2_r6) {
2077 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2078 		/* R2 has Performance Counter Interrupt indicator */
2079 		c->options |= MIPS_CPU_PCI;
2080 	}
2081 	else
2082 		c->srsets = 1;
2083 
2084 	if (cpu_has_mips_r6)
2085 		elf_hwcap |= HWCAP_MIPS_R6;
2086 
2087 	if (cpu_has_msa) {
2088 		c->msa_id = cpu_get_msa_id();
2089 		WARN(c->msa_id & MSA_IR_WRPF,
2090 		     "Vector register partitioning unimplemented!");
2091 		elf_hwcap |= HWCAP_MIPS_MSA;
2092 	}
2093 
2094 	if (cpu_has_vz)
2095 		cpu_probe_vz(c);
2096 
2097 	cpu_probe_vmbits(c);
2098 
2099 #ifdef CONFIG_64BIT
2100 	if (cpu == 0)
2101 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2102 #endif
2103 }
2104 
2105 void cpu_report(void)
2106 {
2107 	struct cpuinfo_mips *c = &current_cpu_data;
2108 
2109 	pr_info("CPU%d revision is: %08x (%s)\n",
2110 		smp_processor_id(), c->processor_id, cpu_name_string());
2111 	if (c->options & MIPS_CPU_FPU)
2112 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2113 	if (cpu_has_msa)
2114 		pr_info("MSA revision is: %08x\n", c->msa_id);
2115 }
2116 
2117 void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
2118 {
2119 	/* Ensure the core number fits in the field */
2120 	WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
2121 			   MIPS_GLOBALNUMBER_CLUSTER_SHF));
2122 
2123 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
2124 	cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
2125 }
2126 
2127 void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
2128 {
2129 	/* Ensure the core number fits in the field */
2130 	WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
2131 
2132 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
2133 	cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
2134 }
2135 
2136 void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
2137 {
2138 	/* Ensure the VP(E) ID fits in the field */
2139 	WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
2140 
2141 	/* Ensure we're not using VP(E)s without support */
2142 	WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
2143 		!IS_ENABLED(CONFIG_CPU_MIPSR6));
2144 
2145 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
2146 	cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
2147 }
2148