xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision c51d39010a1bccc9c1294e2d7c00005aefeb2b5c)
1 /*
2  * Processor capabilities determination functions.
3  *
4  * Copyright (C) xxxx  the Anonymous
5  * Copyright (C) 1994 - 2006 Ralf Baechle
6  * Copyright (C) 2003, 2004  Maciej W. Rozycki
7  * Copyright (C) 2001, 2004, 2011, 2012	 MIPS Technologies, Inc.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/ptrace.h>
17 #include <linux/smp.h>
18 #include <linux/stddef.h>
19 #include <linux/export.h>
20 
21 #include <asm/bugs.h>
22 #include <asm/cpu.h>
23 #include <asm/cpu-features.h>
24 #include <asm/cpu-type.h>
25 #include <asm/fpu.h>
26 #include <asm/mipsregs.h>
27 #include <asm/mipsmtregs.h>
28 #include <asm/msa.h>
29 #include <asm/watch.h>
30 #include <asm/elf.h>
31 #include <asm/pgtable-bits.h>
32 #include <asm/spram.h>
33 #include <asm/uaccess.h>
34 
35 /* Hardware capabilities */
36 unsigned int elf_hwcap __read_mostly;
37 
38 /*
39  * Get the FPU Implementation/Revision.
40  */
41 static inline unsigned long cpu_get_fpu_id(void)
42 {
43 	unsigned long tmp, fpu_id;
44 
45 	tmp = read_c0_status();
46 	__enable_fpu(FPU_AS_IS);
47 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
48 	write_c0_status(tmp);
49 	return fpu_id;
50 }
51 
52 /*
53  * Check if the CPU has an external FPU.
54  */
55 static inline int __cpu_has_fpu(void)
56 {
57 	return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
58 }
59 
60 static inline unsigned long cpu_get_msa_id(void)
61 {
62 	unsigned long status, msa_id;
63 
64 	status = read_c0_status();
65 	__enable_fpu(FPU_64BIT);
66 	enable_msa();
67 	msa_id = read_msa_ir();
68 	disable_msa();
69 	write_c0_status(status);
70 	return msa_id;
71 }
72 
73 /*
74  * Determine the FCSR mask for FPU hardware.
75  */
76 static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_mips *c)
77 {
78 	unsigned long sr, mask, fcsr, fcsr0, fcsr1;
79 
80 	fcsr = c->fpu_csr31;
81 	mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
82 
83 	sr = read_c0_status();
84 	__enable_fpu(FPU_AS_IS);
85 
86 	fcsr0 = fcsr & mask;
87 	write_32bit_cp1_register(CP1_STATUS, fcsr0);
88 	fcsr0 = read_32bit_cp1_register(CP1_STATUS);
89 
90 	fcsr1 = fcsr | ~mask;
91 	write_32bit_cp1_register(CP1_STATUS, fcsr1);
92 	fcsr1 = read_32bit_cp1_register(CP1_STATUS);
93 
94 	write_32bit_cp1_register(CP1_STATUS, fcsr);
95 
96 	write_c0_status(sr);
97 
98 	c->fpu_msk31 = ~(fcsr0 ^ fcsr1) & ~mask;
99 }
100 
101 /*
102  * Determine the IEEE 754 NaN encodings and ABS.fmt/NEG.fmt execution modes
103  * supported by FPU hardware.
104  */
105 static void cpu_set_fpu_2008(struct cpuinfo_mips *c)
106 {
107 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
108 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
109 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
110 		unsigned long sr, fir, fcsr, fcsr0, fcsr1;
111 
112 		sr = read_c0_status();
113 		__enable_fpu(FPU_AS_IS);
114 
115 		fir = read_32bit_cp1_register(CP1_REVISION);
116 		if (fir & MIPS_FPIR_HAS2008) {
117 			fcsr = read_32bit_cp1_register(CP1_STATUS);
118 
119 			fcsr0 = fcsr & ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
120 			write_32bit_cp1_register(CP1_STATUS, fcsr0);
121 			fcsr0 = read_32bit_cp1_register(CP1_STATUS);
122 
123 			fcsr1 = fcsr | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
124 			write_32bit_cp1_register(CP1_STATUS, fcsr1);
125 			fcsr1 = read_32bit_cp1_register(CP1_STATUS);
126 
127 			write_32bit_cp1_register(CP1_STATUS, fcsr);
128 
129 			if (!(fcsr0 & FPU_CSR_NAN2008))
130 				c->options |= MIPS_CPU_NAN_LEGACY;
131 			if (fcsr1 & FPU_CSR_NAN2008)
132 				c->options |= MIPS_CPU_NAN_2008;
133 
134 			if ((fcsr0 ^ fcsr1) & FPU_CSR_ABS2008)
135 				c->fpu_msk31 &= ~FPU_CSR_ABS2008;
136 			else
137 				c->fpu_csr31 |= fcsr & FPU_CSR_ABS2008;
138 
139 			if ((fcsr0 ^ fcsr1) & FPU_CSR_NAN2008)
140 				c->fpu_msk31 &= ~FPU_CSR_NAN2008;
141 			else
142 				c->fpu_csr31 |= fcsr & FPU_CSR_NAN2008;
143 		} else {
144 			c->options |= MIPS_CPU_NAN_LEGACY;
145 		}
146 
147 		write_c0_status(sr);
148 	} else {
149 		c->options |= MIPS_CPU_NAN_LEGACY;
150 	}
151 }
152 
153 /*
154  * IEEE 754 conformance mode to use.  Affects the NaN encoding and the
155  * ABS.fmt/NEG.fmt execution mode.
156  */
157 static enum { STRICT, LEGACY, STD2008, RELAXED } ieee754 = STRICT;
158 
159 /*
160  * Set the IEEE 754 NaN encodings and the ABS.fmt/NEG.fmt execution modes
161  * to support by the FPU emulator according to the IEEE 754 conformance
162  * mode selected.  Note that "relaxed" straps the emulator so that it
163  * allows 2008-NaN binaries even for legacy processors.
164  */
165 static void cpu_set_nofpu_2008(struct cpuinfo_mips *c)
166 {
167 	c->options &= ~(MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY);
168 	c->fpu_csr31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
169 	c->fpu_msk31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
170 
171 	switch (ieee754) {
172 	case STRICT:
173 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
174 				    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
175 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
176 			c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
177 		} else {
178 			c->options |= MIPS_CPU_NAN_LEGACY;
179 			c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
180 		}
181 		break;
182 	case LEGACY:
183 		c->options |= MIPS_CPU_NAN_LEGACY;
184 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
185 		break;
186 	case STD2008:
187 		c->options |= MIPS_CPU_NAN_2008;
188 		c->fpu_csr31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
189 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
190 		break;
191 	case RELAXED:
192 		c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
193 		break;
194 	}
195 }
196 
197 /*
198  * Override the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode
199  * according to the "ieee754=" parameter.
200  */
201 static void cpu_set_nan_2008(struct cpuinfo_mips *c)
202 {
203 	switch (ieee754) {
204 	case STRICT:
205 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
206 		mips_use_nan_2008 = !!cpu_has_nan_2008;
207 		break;
208 	case LEGACY:
209 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
210 		mips_use_nan_2008 = !cpu_has_nan_legacy;
211 		break;
212 	case STD2008:
213 		mips_use_nan_legacy = !cpu_has_nan_2008;
214 		mips_use_nan_2008 = !!cpu_has_nan_2008;
215 		break;
216 	case RELAXED:
217 		mips_use_nan_legacy = true;
218 		mips_use_nan_2008 = true;
219 		break;
220 	}
221 }
222 
223 /*
224  * IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode override
225  * settings:
226  *
227  * strict:  accept binaries that request a NaN encoding supported by the FPU
228  * legacy:  only accept legacy-NaN binaries
229  * 2008:    only accept 2008-NaN binaries
230  * relaxed: accept any binaries regardless of whether supported by the FPU
231  */
232 static int __init ieee754_setup(char *s)
233 {
234 	if (!s)
235 		return -1;
236 	else if (!strcmp(s, "strict"))
237 		ieee754 = STRICT;
238 	else if (!strcmp(s, "legacy"))
239 		ieee754 = LEGACY;
240 	else if (!strcmp(s, "2008"))
241 		ieee754 = STD2008;
242 	else if (!strcmp(s, "relaxed"))
243 		ieee754 = RELAXED;
244 	else
245 		return -1;
246 
247 	if (!(boot_cpu_data.options & MIPS_CPU_FPU))
248 		cpu_set_nofpu_2008(&boot_cpu_data);
249 	cpu_set_nan_2008(&boot_cpu_data);
250 
251 	return 0;
252 }
253 
254 early_param("ieee754", ieee754_setup);
255 
256 /*
257  * Set the FIR feature flags for the FPU emulator.
258  */
259 static void cpu_set_nofpu_id(struct cpuinfo_mips *c)
260 {
261 	u32 value;
262 
263 	value = 0;
264 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
265 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
266 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
267 		value |= MIPS_FPIR_D | MIPS_FPIR_S;
268 	if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
269 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
270 		value |= MIPS_FPIR_F64 | MIPS_FPIR_L | MIPS_FPIR_W;
271 	if (c->options & MIPS_CPU_NAN_2008)
272 		value |= MIPS_FPIR_HAS2008;
273 	c->fpu_id = value;
274 }
275 
276 /* Determined FPU emulator mask to use for the boot CPU with "nofpu".  */
277 static unsigned int mips_nofpu_msk31;
278 
279 /*
280  * Set options for FPU hardware.
281  */
282 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
283 {
284 	c->fpu_id = cpu_get_fpu_id();
285 	mips_nofpu_msk31 = c->fpu_msk31;
286 
287 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
288 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
289 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
290 		if (c->fpu_id & MIPS_FPIR_3D)
291 			c->ases |= MIPS_ASE_MIPS3D;
292 		if (c->fpu_id & MIPS_FPIR_FREP)
293 			c->options |= MIPS_CPU_FRE;
294 	}
295 
296 	cpu_set_fpu_fcsr_mask(c);
297 	cpu_set_fpu_2008(c);
298 	cpu_set_nan_2008(c);
299 }
300 
301 /*
302  * Set options for the FPU emulator.
303  */
304 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
305 {
306 	c->options &= ~MIPS_CPU_FPU;
307 	c->fpu_msk31 = mips_nofpu_msk31;
308 
309 	cpu_set_nofpu_2008(c);
310 	cpu_set_nan_2008(c);
311 	cpu_set_nofpu_id(c);
312 }
313 
314 static int mips_fpu_disabled;
315 
316 static int __init fpu_disable(char *s)
317 {
318 	cpu_set_nofpu_opts(&boot_cpu_data);
319 	mips_fpu_disabled = 1;
320 
321 	return 1;
322 }
323 
324 __setup("nofpu", fpu_disable);
325 
326 int mips_dsp_disabled;
327 
328 static int __init dsp_disable(char *s)
329 {
330 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
331 	mips_dsp_disabled = 1;
332 
333 	return 1;
334 }
335 
336 __setup("nodsp", dsp_disable);
337 
338 static int mips_htw_disabled;
339 
340 static int __init htw_disable(char *s)
341 {
342 	mips_htw_disabled = 1;
343 	cpu_data[0].options &= ~MIPS_CPU_HTW;
344 	write_c0_pwctl(read_c0_pwctl() &
345 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
346 
347 	return 1;
348 }
349 
350 __setup("nohtw", htw_disable);
351 
352 static int mips_ftlb_disabled;
353 static int mips_has_ftlb_configured;
354 
355 enum ftlb_flags {
356 	FTLB_EN		= 1 << 0,
357 	FTLB_SET_PROB	= 1 << 1,
358 };
359 
360 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
361 
362 static int __init ftlb_disable(char *s)
363 {
364 	unsigned int config4, mmuextdef;
365 
366 	/*
367 	 * If the core hasn't done any FTLB configuration, there is nothing
368 	 * for us to do here.
369 	 */
370 	if (!mips_has_ftlb_configured)
371 		return 1;
372 
373 	/* Disable it in the boot cpu */
374 	if (set_ftlb_enable(&cpu_data[0], 0)) {
375 		pr_warn("Can't turn FTLB off\n");
376 		return 1;
377 	}
378 
379 	config4 = read_c0_config4();
380 
381 	/* Check that FTLB has been disabled */
382 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
383 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
384 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
385 		/* This should never happen */
386 		pr_warn("FTLB could not be disabled!\n");
387 		return 1;
388 	}
389 
390 	mips_ftlb_disabled = 1;
391 	mips_has_ftlb_configured = 0;
392 
393 	/*
394 	 * noftlb is mainly used for debug purposes so print
395 	 * an informative message instead of using pr_debug()
396 	 */
397 	pr_info("FTLB has been disabled\n");
398 
399 	/*
400 	 * Some of these bits are duplicated in the decode_config4.
401 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
402 	 * once FTLB has been disabled so undo what decode_config4 did.
403 	 */
404 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
405 			       cpu_data[0].tlbsizeftlbsets;
406 	cpu_data[0].tlbsizeftlbsets = 0;
407 	cpu_data[0].tlbsizeftlbways = 0;
408 
409 	return 1;
410 }
411 
412 __setup("noftlb", ftlb_disable);
413 
414 
415 static inline void check_errata(void)
416 {
417 	struct cpuinfo_mips *c = &current_cpu_data;
418 
419 	switch (current_cpu_type()) {
420 	case CPU_34K:
421 		/*
422 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
423 		 * This code only handles VPE0, any SMP/RTOS code
424 		 * making use of VPE1 will be responsable for that VPE.
425 		 */
426 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
427 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
428 		break;
429 	default:
430 		break;
431 	}
432 }
433 
434 void __init check_bugs32(void)
435 {
436 	check_errata();
437 }
438 
439 /*
440  * Probe whether cpu has config register by trying to play with
441  * alternate cache bit and see whether it matters.
442  * It's used by cpu_probe to distinguish between R3000A and R3081.
443  */
444 static inline int cpu_has_confreg(void)
445 {
446 #ifdef CONFIG_CPU_R3000
447 	extern unsigned long r3k_cache_size(unsigned long);
448 	unsigned long size1, size2;
449 	unsigned long cfg = read_c0_conf();
450 
451 	size1 = r3k_cache_size(ST0_ISC);
452 	write_c0_conf(cfg ^ R30XX_CONF_AC);
453 	size2 = r3k_cache_size(ST0_ISC);
454 	write_c0_conf(cfg);
455 	return size1 != size2;
456 #else
457 	return 0;
458 #endif
459 }
460 
461 static inline void set_elf_platform(int cpu, const char *plat)
462 {
463 	if (cpu == 0)
464 		__elf_platform = plat;
465 }
466 
467 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
468 {
469 #ifdef __NEED_VMBITS_PROBE
470 	write_c0_entryhi(0x3fffffffffffe000ULL);
471 	back_to_back_c0_hazard();
472 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
473 #endif
474 }
475 
476 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
477 {
478 	switch (isa) {
479 	case MIPS_CPU_ISA_M64R2:
480 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
481 	case MIPS_CPU_ISA_M64R1:
482 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
483 	case MIPS_CPU_ISA_V:
484 		c->isa_level |= MIPS_CPU_ISA_V;
485 	case MIPS_CPU_ISA_IV:
486 		c->isa_level |= MIPS_CPU_ISA_IV;
487 	case MIPS_CPU_ISA_III:
488 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
489 		break;
490 
491 	/* R6 incompatible with everything else */
492 	case MIPS_CPU_ISA_M64R6:
493 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
494 	case MIPS_CPU_ISA_M32R6:
495 		c->isa_level |= MIPS_CPU_ISA_M32R6;
496 		/* Break here so we don't add incompatible ISAs */
497 		break;
498 	case MIPS_CPU_ISA_M32R2:
499 		c->isa_level |= MIPS_CPU_ISA_M32R2;
500 	case MIPS_CPU_ISA_M32R1:
501 		c->isa_level |= MIPS_CPU_ISA_M32R1;
502 	case MIPS_CPU_ISA_II:
503 		c->isa_level |= MIPS_CPU_ISA_II;
504 		break;
505 	}
506 }
507 
508 static char unknown_isa[] = KERN_ERR \
509 	"Unsupported ISA type, c0.config0: %d.";
510 
511 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
512 {
513 
514 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
515 
516 	/*
517 	 * 0 = All TLBWR instructions go to FTLB
518 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
519 	 * FTLB and 1 goes to the VTLB.
520 	 * 2 = 7:1: As above with 7:1 ratio.
521 	 * 3 = 3:1: As above with 3:1 ratio.
522 	 *
523 	 * Use the linear midpoint as the probability threshold.
524 	 */
525 	if (probability >= 12)
526 		return 1;
527 	else if (probability >= 6)
528 		return 2;
529 	else
530 		/*
531 		 * So FTLB is less than 4 times bigger than VTLB.
532 		 * A 3:1 ratio can still be useful though.
533 		 */
534 		return 3;
535 }
536 
537 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
538 {
539 	unsigned int config;
540 
541 	/* It's implementation dependent how the FTLB can be enabled */
542 	switch (c->cputype) {
543 	case CPU_PROAPTIV:
544 	case CPU_P5600:
545 	case CPU_P6600:
546 		/* proAptiv & related cores use Config6 to enable the FTLB */
547 		config = read_c0_config6();
548 
549 		if (flags & FTLB_EN)
550 			config |= MIPS_CONF6_FTLBEN;
551 		else
552 			config &= ~MIPS_CONF6_FTLBEN;
553 
554 		if (flags & FTLB_SET_PROB) {
555 			config &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
556 			config |= calculate_ftlb_probability(c)
557 				  << MIPS_CONF6_FTLBP_SHIFT;
558 		}
559 
560 		write_c0_config6(config);
561 		back_to_back_c0_hazard();
562 		break;
563 	case CPU_I6400:
564 		/* There's no way to disable the FTLB */
565 		if (!(flags & FTLB_EN))
566 			return 1;
567 		return 0;
568 	case CPU_LOONGSON3:
569 		/* Flush ITLB, DTLB, VTLB and FTLB */
570 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
571 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
572 		/* Loongson-3 cores use Config6 to enable the FTLB */
573 		config = read_c0_config6();
574 		if (flags & FTLB_EN)
575 			/* Enable FTLB */
576 			write_c0_config6(config & ~MIPS_CONF6_FTLBDIS);
577 		else
578 			/* Disable FTLB */
579 			write_c0_config6(config | MIPS_CONF6_FTLBDIS);
580 		break;
581 	default:
582 		return 1;
583 	}
584 
585 	return 0;
586 }
587 
588 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
589 {
590 	unsigned int config0;
591 	int isa, mt;
592 
593 	config0 = read_c0_config();
594 
595 	/*
596 	 * Look for Standard TLB or Dual VTLB and FTLB
597 	 */
598 	mt = config0 & MIPS_CONF_MT;
599 	if (mt == MIPS_CONF_MT_TLB)
600 		c->options |= MIPS_CPU_TLB;
601 	else if (mt == MIPS_CONF_MT_FTLB)
602 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
603 
604 	isa = (config0 & MIPS_CONF_AT) >> 13;
605 	switch (isa) {
606 	case 0:
607 		switch ((config0 & MIPS_CONF_AR) >> 10) {
608 		case 0:
609 			set_isa(c, MIPS_CPU_ISA_M32R1);
610 			break;
611 		case 1:
612 			set_isa(c, MIPS_CPU_ISA_M32R2);
613 			break;
614 		case 2:
615 			set_isa(c, MIPS_CPU_ISA_M32R6);
616 			break;
617 		default:
618 			goto unknown;
619 		}
620 		break;
621 	case 2:
622 		switch ((config0 & MIPS_CONF_AR) >> 10) {
623 		case 0:
624 			set_isa(c, MIPS_CPU_ISA_M64R1);
625 			break;
626 		case 1:
627 			set_isa(c, MIPS_CPU_ISA_M64R2);
628 			break;
629 		case 2:
630 			set_isa(c, MIPS_CPU_ISA_M64R6);
631 			break;
632 		default:
633 			goto unknown;
634 		}
635 		break;
636 	default:
637 		goto unknown;
638 	}
639 
640 	return config0 & MIPS_CONF_M;
641 
642 unknown:
643 	panic(unknown_isa, config0);
644 }
645 
646 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
647 {
648 	unsigned int config1;
649 
650 	config1 = read_c0_config1();
651 
652 	if (config1 & MIPS_CONF1_MD)
653 		c->ases |= MIPS_ASE_MDMX;
654 	if (config1 & MIPS_CONF1_PC)
655 		c->options |= MIPS_CPU_PERF;
656 	if (config1 & MIPS_CONF1_WR)
657 		c->options |= MIPS_CPU_WATCH;
658 	if (config1 & MIPS_CONF1_CA)
659 		c->ases |= MIPS_ASE_MIPS16;
660 	if (config1 & MIPS_CONF1_EP)
661 		c->options |= MIPS_CPU_EJTAG;
662 	if (config1 & MIPS_CONF1_FP) {
663 		c->options |= MIPS_CPU_FPU;
664 		c->options |= MIPS_CPU_32FPR;
665 	}
666 	if (cpu_has_tlb) {
667 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
668 		c->tlbsizevtlb = c->tlbsize;
669 		c->tlbsizeftlbsets = 0;
670 	}
671 
672 	return config1 & MIPS_CONF_M;
673 }
674 
675 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
676 {
677 	unsigned int config2;
678 
679 	config2 = read_c0_config2();
680 
681 	if (config2 & MIPS_CONF2_SL)
682 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
683 
684 	return config2 & MIPS_CONF_M;
685 }
686 
687 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
688 {
689 	unsigned int config3;
690 
691 	config3 = read_c0_config3();
692 
693 	if (config3 & MIPS_CONF3_SM) {
694 		c->ases |= MIPS_ASE_SMARTMIPS;
695 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
696 	}
697 	if (config3 & MIPS_CONF3_RXI)
698 		c->options |= MIPS_CPU_RIXI;
699 	if (config3 & MIPS_CONF3_CTXTC)
700 		c->options |= MIPS_CPU_CTXTC;
701 	if (config3 & MIPS_CONF3_DSP)
702 		c->ases |= MIPS_ASE_DSP;
703 	if (config3 & MIPS_CONF3_DSP2P) {
704 		c->ases |= MIPS_ASE_DSP2P;
705 		if (cpu_has_mips_r6)
706 			c->ases |= MIPS_ASE_DSP3;
707 	}
708 	if (config3 & MIPS_CONF3_VINT)
709 		c->options |= MIPS_CPU_VINT;
710 	if (config3 & MIPS_CONF3_VEIC)
711 		c->options |= MIPS_CPU_VEIC;
712 	if (config3 & MIPS_CONF3_LPA)
713 		c->options |= MIPS_CPU_LPA;
714 	if (config3 & MIPS_CONF3_MT)
715 		c->ases |= MIPS_ASE_MIPSMT;
716 	if (config3 & MIPS_CONF3_ULRI)
717 		c->options |= MIPS_CPU_ULRI;
718 	if (config3 & MIPS_CONF3_ISA)
719 		c->options |= MIPS_CPU_MICROMIPS;
720 	if (config3 & MIPS_CONF3_VZ)
721 		c->ases |= MIPS_ASE_VZ;
722 	if (config3 & MIPS_CONF3_SC)
723 		c->options |= MIPS_CPU_SEGMENTS;
724 	if (config3 & MIPS_CONF3_BI)
725 		c->options |= MIPS_CPU_BADINSTR;
726 	if (config3 & MIPS_CONF3_BP)
727 		c->options |= MIPS_CPU_BADINSTRP;
728 	if (config3 & MIPS_CONF3_MSA)
729 		c->ases |= MIPS_ASE_MSA;
730 	if (config3 & MIPS_CONF3_PW) {
731 		c->htw_seq = 0;
732 		c->options |= MIPS_CPU_HTW;
733 	}
734 	if (config3 & MIPS_CONF3_CDMM)
735 		c->options |= MIPS_CPU_CDMM;
736 	if (config3 & MIPS_CONF3_SP)
737 		c->options |= MIPS_CPU_SP;
738 
739 	return config3 & MIPS_CONF_M;
740 }
741 
742 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
743 {
744 	unsigned int config4;
745 	unsigned int newcf4;
746 	unsigned int mmuextdef;
747 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
748 	unsigned long asid_mask;
749 
750 	config4 = read_c0_config4();
751 
752 	if (cpu_has_tlb) {
753 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
754 			c->options |= MIPS_CPU_TLBINV;
755 
756 		/*
757 		 * R6 has dropped the MMUExtDef field from config4.
758 		 * On R6 the fields always describe the FTLB, and only if it is
759 		 * present according to Config.MT.
760 		 */
761 		if (!cpu_has_mips_r6)
762 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
763 		else if (cpu_has_ftlb)
764 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
765 		else
766 			mmuextdef = 0;
767 
768 		switch (mmuextdef) {
769 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
770 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
771 			c->tlbsizevtlb = c->tlbsize;
772 			break;
773 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
774 			c->tlbsizevtlb +=
775 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
776 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
777 			c->tlbsize = c->tlbsizevtlb;
778 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
779 			/* fall through */
780 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
781 			if (mips_ftlb_disabled)
782 				break;
783 			newcf4 = (config4 & ~ftlb_page) |
784 				(page_size_ftlb(mmuextdef) <<
785 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
786 			write_c0_config4(newcf4);
787 			back_to_back_c0_hazard();
788 			config4 = read_c0_config4();
789 			if (config4 != newcf4) {
790 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
791 				       PAGE_SIZE, config4);
792 				/* Switch FTLB off */
793 				set_ftlb_enable(c, 0);
794 				mips_ftlb_disabled = 1;
795 				break;
796 			}
797 			c->tlbsizeftlbsets = 1 <<
798 				((config4 & MIPS_CONF4_FTLBSETS) >>
799 				 MIPS_CONF4_FTLBSETS_SHIFT);
800 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
801 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
802 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
803 			mips_has_ftlb_configured = 1;
804 			break;
805 		}
806 	}
807 
808 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
809 				>> MIPS_CONF4_KSCREXIST_SHIFT;
810 
811 	asid_mask = MIPS_ENTRYHI_ASID;
812 	if (config4 & MIPS_CONF4_AE)
813 		asid_mask |= MIPS_ENTRYHI_ASIDX;
814 	set_cpu_asid_mask(c, asid_mask);
815 
816 	/*
817 	 * Warn if the computed ASID mask doesn't match the mask the kernel
818 	 * is built for. This may indicate either a serious problem or an
819 	 * easy optimisation opportunity, but either way should be addressed.
820 	 */
821 	WARN_ON(asid_mask != cpu_asid_mask(c));
822 
823 	return config4 & MIPS_CONF_M;
824 }
825 
826 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
827 {
828 	unsigned int config5;
829 
830 	config5 = read_c0_config5();
831 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
832 	write_c0_config5(config5);
833 
834 	if (config5 & MIPS_CONF5_EVA)
835 		c->options |= MIPS_CPU_EVA;
836 	if (config5 & MIPS_CONF5_MRP)
837 		c->options |= MIPS_CPU_MAAR;
838 	if (config5 & MIPS_CONF5_LLB)
839 		c->options |= MIPS_CPU_RW_LLB;
840 	if (config5 & MIPS_CONF5_MVH)
841 		c->options |= MIPS_CPU_MVH;
842 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
843 		c->options |= MIPS_CPU_VP;
844 
845 	return config5 & MIPS_CONF_M;
846 }
847 
848 static void decode_configs(struct cpuinfo_mips *c)
849 {
850 	int ok;
851 
852 	/* MIPS32 or MIPS64 compliant CPU.  */
853 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
854 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
855 
856 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
857 
858 	/* Enable FTLB if present and not disabled */
859 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
860 
861 	ok = decode_config0(c);			/* Read Config registers.  */
862 	BUG_ON(!ok);				/* Arch spec violation!	 */
863 	if (ok)
864 		ok = decode_config1(c);
865 	if (ok)
866 		ok = decode_config2(c);
867 	if (ok)
868 		ok = decode_config3(c);
869 	if (ok)
870 		ok = decode_config4(c);
871 	if (ok)
872 		ok = decode_config5(c);
873 
874 	/* Probe the EBase.WG bit */
875 	if (cpu_has_mips_r2_r6) {
876 		u64 ebase;
877 		unsigned int status;
878 
879 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
880 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
881 					 : (s32)read_c0_ebase();
882 		if (ebase & MIPS_EBASE_WG) {
883 			/* WG bit already set, we can avoid the clumsy probe */
884 			c->options |= MIPS_CPU_EBASE_WG;
885 		} else {
886 			/* Its UNDEFINED to change EBase while BEV=0 */
887 			status = read_c0_status();
888 			write_c0_status(status | ST0_BEV);
889 			irq_enable_hazard();
890 			/*
891 			 * On pre-r6 cores, this may well clobber the upper bits
892 			 * of EBase. This is hard to avoid without potentially
893 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
894 			 */
895 			if (cpu_has_mips64r6)
896 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
897 			else
898 				write_c0_ebase(ebase | MIPS_EBASE_WG);
899 			back_to_back_c0_hazard();
900 			/* Restore BEV */
901 			write_c0_status(status);
902 			if (read_c0_ebase() & MIPS_EBASE_WG) {
903 				c->options |= MIPS_CPU_EBASE_WG;
904 				write_c0_ebase(ebase);
905 			}
906 		}
907 	}
908 
909 	/* configure the FTLB write probability */
910 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
911 
912 	mips_probe_watch_registers(c);
913 
914 #ifndef CONFIG_MIPS_CPS
915 	if (cpu_has_mips_r2_r6) {
916 		c->core = get_ebase_cpunum();
917 		if (cpu_has_mipsmt)
918 			c->core >>= fls(core_nvpes()) - 1;
919 	}
920 #endif
921 }
922 
923 /*
924  * Probe for certain guest capabilities by writing config bits and reading back.
925  * Finally write back the original value.
926  */
927 #define probe_gc0_config(name, maxconf, bits)				\
928 do {									\
929 	unsigned int tmp;						\
930 	tmp = read_gc0_##name();					\
931 	write_gc0_##name(tmp | (bits));					\
932 	back_to_back_c0_hazard();					\
933 	maxconf = read_gc0_##name();					\
934 	write_gc0_##name(tmp);						\
935 } while (0)
936 
937 /*
938  * Probe for dynamic guest capabilities by changing certain config bits and
939  * reading back to see if they change. Finally write back the original value.
940  */
941 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
942 do {									\
943 	maxconf = read_gc0_##name();					\
944 	write_gc0_##name(maxconf ^ (bits));				\
945 	back_to_back_c0_hazard();					\
946 	dynconf = maxconf ^ read_gc0_##name();				\
947 	write_gc0_##name(maxconf);					\
948 	maxconf |= dynconf;						\
949 } while (0)
950 
951 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
952 {
953 	unsigned int config0;
954 
955 	probe_gc0_config(config, config0, MIPS_CONF_M);
956 
957 	if (config0 & MIPS_CONF_M)
958 		c->guest.conf |= BIT(1);
959 	return config0 & MIPS_CONF_M;
960 }
961 
962 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
963 {
964 	unsigned int config1, config1_dyn;
965 
966 	probe_gc0_config_dyn(config1, config1, config1_dyn,
967 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
968 			     MIPS_CONF1_FP);
969 
970 	if (config1 & MIPS_CONF1_FP)
971 		c->guest.options |= MIPS_CPU_FPU;
972 	if (config1_dyn & MIPS_CONF1_FP)
973 		c->guest.options_dyn |= MIPS_CPU_FPU;
974 
975 	if (config1 & MIPS_CONF1_WR)
976 		c->guest.options |= MIPS_CPU_WATCH;
977 	if (config1_dyn & MIPS_CONF1_WR)
978 		c->guest.options_dyn |= MIPS_CPU_WATCH;
979 
980 	if (config1 & MIPS_CONF1_PC)
981 		c->guest.options |= MIPS_CPU_PERF;
982 	if (config1_dyn & MIPS_CONF1_PC)
983 		c->guest.options_dyn |= MIPS_CPU_PERF;
984 
985 	if (config1 & MIPS_CONF_M)
986 		c->guest.conf |= BIT(2);
987 	return config1 & MIPS_CONF_M;
988 }
989 
990 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
991 {
992 	unsigned int config2;
993 
994 	probe_gc0_config(config2, config2, MIPS_CONF_M);
995 
996 	if (config2 & MIPS_CONF_M)
997 		c->guest.conf |= BIT(3);
998 	return config2 & MIPS_CONF_M;
999 }
1000 
1001 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
1002 {
1003 	unsigned int config3, config3_dyn;
1004 
1005 	probe_gc0_config_dyn(config3, config3, config3_dyn,
1006 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_CTXTC);
1007 
1008 	if (config3 & MIPS_CONF3_CTXTC)
1009 		c->guest.options |= MIPS_CPU_CTXTC;
1010 	if (config3_dyn & MIPS_CONF3_CTXTC)
1011 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
1012 
1013 	if (config3 & MIPS_CONF3_PW)
1014 		c->guest.options |= MIPS_CPU_HTW;
1015 
1016 	if (config3 & MIPS_CONF3_SC)
1017 		c->guest.options |= MIPS_CPU_SEGMENTS;
1018 
1019 	if (config3 & MIPS_CONF3_BI)
1020 		c->guest.options |= MIPS_CPU_BADINSTR;
1021 	if (config3 & MIPS_CONF3_BP)
1022 		c->guest.options |= MIPS_CPU_BADINSTRP;
1023 
1024 	if (config3 & MIPS_CONF3_MSA)
1025 		c->guest.ases |= MIPS_ASE_MSA;
1026 	if (config3_dyn & MIPS_CONF3_MSA)
1027 		c->guest.ases_dyn |= MIPS_ASE_MSA;
1028 
1029 	if (config3 & MIPS_CONF_M)
1030 		c->guest.conf |= BIT(4);
1031 	return config3 & MIPS_CONF_M;
1032 }
1033 
1034 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
1035 {
1036 	unsigned int config4;
1037 
1038 	probe_gc0_config(config4, config4,
1039 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
1040 
1041 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
1042 				>> MIPS_CONF4_KSCREXIST_SHIFT;
1043 
1044 	if (config4 & MIPS_CONF_M)
1045 		c->guest.conf |= BIT(5);
1046 	return config4 & MIPS_CONF_M;
1047 }
1048 
1049 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
1050 {
1051 	unsigned int config5, config5_dyn;
1052 
1053 	probe_gc0_config_dyn(config5, config5, config5_dyn,
1054 			 MIPS_CONF_M | MIPS_CONF5_MRP);
1055 
1056 	if (config5 & MIPS_CONF5_MRP)
1057 		c->guest.options |= MIPS_CPU_MAAR;
1058 	if (config5_dyn & MIPS_CONF5_MRP)
1059 		c->guest.options_dyn |= MIPS_CPU_MAAR;
1060 
1061 	if (config5 & MIPS_CONF5_LLB)
1062 		c->guest.options |= MIPS_CPU_RW_LLB;
1063 
1064 	if (config5 & MIPS_CONF_M)
1065 		c->guest.conf |= BIT(6);
1066 	return config5 & MIPS_CONF_M;
1067 }
1068 
1069 static inline void decode_guest_configs(struct cpuinfo_mips *c)
1070 {
1071 	unsigned int ok;
1072 
1073 	ok = decode_guest_config0(c);
1074 	if (ok)
1075 		ok = decode_guest_config1(c);
1076 	if (ok)
1077 		ok = decode_guest_config2(c);
1078 	if (ok)
1079 		ok = decode_guest_config3(c);
1080 	if (ok)
1081 		ok = decode_guest_config4(c);
1082 	if (ok)
1083 		decode_guest_config5(c);
1084 }
1085 
1086 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
1087 {
1088 	unsigned int guestctl0, temp;
1089 
1090 	guestctl0 = read_c0_guestctl0();
1091 
1092 	if (guestctl0 & MIPS_GCTL0_G0E)
1093 		c->options |= MIPS_CPU_GUESTCTL0EXT;
1094 	if (guestctl0 & MIPS_GCTL0_G1)
1095 		c->options |= MIPS_CPU_GUESTCTL1;
1096 	if (guestctl0 & MIPS_GCTL0_G2)
1097 		c->options |= MIPS_CPU_GUESTCTL2;
1098 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
1099 		c->options |= MIPS_CPU_GUESTID;
1100 
1101 		/*
1102 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
1103 		 * first, otherwise all data accesses will be fully virtualised
1104 		 * as if they were performed by guest mode.
1105 		 */
1106 		write_c0_guestctl1(0);
1107 		tlbw_use_hazard();
1108 
1109 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
1110 		back_to_back_c0_hazard();
1111 		temp = read_c0_guestctl0();
1112 
1113 		if (temp & MIPS_GCTL0_DRG) {
1114 			write_c0_guestctl0(guestctl0);
1115 			c->options |= MIPS_CPU_DRG;
1116 		}
1117 	}
1118 }
1119 
1120 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1121 {
1122 	if (cpu_has_guestid) {
1123 		/* determine the number of bits of GuestID available */
1124 		write_c0_guestctl1(MIPS_GCTL1_ID);
1125 		back_to_back_c0_hazard();
1126 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1127 						>> MIPS_GCTL1_ID_SHIFT;
1128 		write_c0_guestctl1(0);
1129 	}
1130 }
1131 
1132 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1133 {
1134 	/* determine the number of bits of GTOffset available */
1135 	write_c0_gtoffset(0xffffffff);
1136 	back_to_back_c0_hazard();
1137 	c->gtoffset_mask = read_c0_gtoffset();
1138 	write_c0_gtoffset(0);
1139 }
1140 
1141 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1142 {
1143 	cpu_probe_guestctl0(c);
1144 	if (cpu_has_guestctl1)
1145 		cpu_probe_guestctl1(c);
1146 
1147 	cpu_probe_gtoffset(c);
1148 
1149 	decode_guest_configs(c);
1150 }
1151 
1152 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1153 		| MIPS_CPU_COUNTER)
1154 
1155 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1156 {
1157 	switch (c->processor_id & PRID_IMP_MASK) {
1158 	case PRID_IMP_R2000:
1159 		c->cputype = CPU_R2000;
1160 		__cpu_name[cpu] = "R2000";
1161 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1162 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1163 			     MIPS_CPU_NOFPUEX;
1164 		if (__cpu_has_fpu())
1165 			c->options |= MIPS_CPU_FPU;
1166 		c->tlbsize = 64;
1167 		break;
1168 	case PRID_IMP_R3000:
1169 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1170 			if (cpu_has_confreg()) {
1171 				c->cputype = CPU_R3081E;
1172 				__cpu_name[cpu] = "R3081";
1173 			} else {
1174 				c->cputype = CPU_R3000A;
1175 				__cpu_name[cpu] = "R3000A";
1176 			}
1177 		} else {
1178 			c->cputype = CPU_R3000;
1179 			__cpu_name[cpu] = "R3000";
1180 		}
1181 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1182 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1183 			     MIPS_CPU_NOFPUEX;
1184 		if (__cpu_has_fpu())
1185 			c->options |= MIPS_CPU_FPU;
1186 		c->tlbsize = 64;
1187 		break;
1188 	case PRID_IMP_R4000:
1189 		if (read_c0_config() & CONF_SC) {
1190 			if ((c->processor_id & PRID_REV_MASK) >=
1191 			    PRID_REV_R4400) {
1192 				c->cputype = CPU_R4400PC;
1193 				__cpu_name[cpu] = "R4400PC";
1194 			} else {
1195 				c->cputype = CPU_R4000PC;
1196 				__cpu_name[cpu] = "R4000PC";
1197 			}
1198 		} else {
1199 			int cca = read_c0_config() & CONF_CM_CMASK;
1200 			int mc;
1201 
1202 			/*
1203 			 * SC and MC versions can't be reliably told apart,
1204 			 * but only the latter support coherent caching
1205 			 * modes so assume the firmware has set the KSEG0
1206 			 * coherency attribute reasonably (if uncached, we
1207 			 * assume SC).
1208 			 */
1209 			switch (cca) {
1210 			case CONF_CM_CACHABLE_CE:
1211 			case CONF_CM_CACHABLE_COW:
1212 			case CONF_CM_CACHABLE_CUW:
1213 				mc = 1;
1214 				break;
1215 			default:
1216 				mc = 0;
1217 				break;
1218 			}
1219 			if ((c->processor_id & PRID_REV_MASK) >=
1220 			    PRID_REV_R4400) {
1221 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1222 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1223 			} else {
1224 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1225 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1226 			}
1227 		}
1228 
1229 		set_isa(c, MIPS_CPU_ISA_III);
1230 		c->fpu_msk31 |= FPU_CSR_CONDX;
1231 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1232 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1233 			     MIPS_CPU_LLSC;
1234 		c->tlbsize = 48;
1235 		break;
1236 	case PRID_IMP_VR41XX:
1237 		set_isa(c, MIPS_CPU_ISA_III);
1238 		c->fpu_msk31 |= FPU_CSR_CONDX;
1239 		c->options = R4K_OPTS;
1240 		c->tlbsize = 32;
1241 		switch (c->processor_id & 0xf0) {
1242 		case PRID_REV_VR4111:
1243 			c->cputype = CPU_VR4111;
1244 			__cpu_name[cpu] = "NEC VR4111";
1245 			break;
1246 		case PRID_REV_VR4121:
1247 			c->cputype = CPU_VR4121;
1248 			__cpu_name[cpu] = "NEC VR4121";
1249 			break;
1250 		case PRID_REV_VR4122:
1251 			if ((c->processor_id & 0xf) < 0x3) {
1252 				c->cputype = CPU_VR4122;
1253 				__cpu_name[cpu] = "NEC VR4122";
1254 			} else {
1255 				c->cputype = CPU_VR4181A;
1256 				__cpu_name[cpu] = "NEC VR4181A";
1257 			}
1258 			break;
1259 		case PRID_REV_VR4130:
1260 			if ((c->processor_id & 0xf) < 0x4) {
1261 				c->cputype = CPU_VR4131;
1262 				__cpu_name[cpu] = "NEC VR4131";
1263 			} else {
1264 				c->cputype = CPU_VR4133;
1265 				c->options |= MIPS_CPU_LLSC;
1266 				__cpu_name[cpu] = "NEC VR4133";
1267 			}
1268 			break;
1269 		default:
1270 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1271 			c->cputype = CPU_VR41XX;
1272 			__cpu_name[cpu] = "NEC Vr41xx";
1273 			break;
1274 		}
1275 		break;
1276 	case PRID_IMP_R4300:
1277 		c->cputype = CPU_R4300;
1278 		__cpu_name[cpu] = "R4300";
1279 		set_isa(c, MIPS_CPU_ISA_III);
1280 		c->fpu_msk31 |= FPU_CSR_CONDX;
1281 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1282 			     MIPS_CPU_LLSC;
1283 		c->tlbsize = 32;
1284 		break;
1285 	case PRID_IMP_R4600:
1286 		c->cputype = CPU_R4600;
1287 		__cpu_name[cpu] = "R4600";
1288 		set_isa(c, MIPS_CPU_ISA_III);
1289 		c->fpu_msk31 |= FPU_CSR_CONDX;
1290 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1291 			     MIPS_CPU_LLSC;
1292 		c->tlbsize = 48;
1293 		break;
1294 	#if 0
1295 	case PRID_IMP_R4650:
1296 		/*
1297 		 * This processor doesn't have an MMU, so it's not
1298 		 * "real easy" to run Linux on it. It is left purely
1299 		 * for documentation.  Commented out because it shares
1300 		 * it's c0_prid id number with the TX3900.
1301 		 */
1302 		c->cputype = CPU_R4650;
1303 		__cpu_name[cpu] = "R4650";
1304 		set_isa(c, MIPS_CPU_ISA_III);
1305 		c->fpu_msk31 |= FPU_CSR_CONDX;
1306 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1307 		c->tlbsize = 48;
1308 		break;
1309 	#endif
1310 	case PRID_IMP_TX39:
1311 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1312 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1313 
1314 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1315 			c->cputype = CPU_TX3927;
1316 			__cpu_name[cpu] = "TX3927";
1317 			c->tlbsize = 64;
1318 		} else {
1319 			switch (c->processor_id & PRID_REV_MASK) {
1320 			case PRID_REV_TX3912:
1321 				c->cputype = CPU_TX3912;
1322 				__cpu_name[cpu] = "TX3912";
1323 				c->tlbsize = 32;
1324 				break;
1325 			case PRID_REV_TX3922:
1326 				c->cputype = CPU_TX3922;
1327 				__cpu_name[cpu] = "TX3922";
1328 				c->tlbsize = 64;
1329 				break;
1330 			}
1331 		}
1332 		break;
1333 	case PRID_IMP_R4700:
1334 		c->cputype = CPU_R4700;
1335 		__cpu_name[cpu] = "R4700";
1336 		set_isa(c, MIPS_CPU_ISA_III);
1337 		c->fpu_msk31 |= FPU_CSR_CONDX;
1338 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1339 			     MIPS_CPU_LLSC;
1340 		c->tlbsize = 48;
1341 		break;
1342 	case PRID_IMP_TX49:
1343 		c->cputype = CPU_TX49XX;
1344 		__cpu_name[cpu] = "R49XX";
1345 		set_isa(c, MIPS_CPU_ISA_III);
1346 		c->fpu_msk31 |= FPU_CSR_CONDX;
1347 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1348 		if (!(c->processor_id & 0x08))
1349 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1350 		c->tlbsize = 48;
1351 		break;
1352 	case PRID_IMP_R5000:
1353 		c->cputype = CPU_R5000;
1354 		__cpu_name[cpu] = "R5000";
1355 		set_isa(c, MIPS_CPU_ISA_IV);
1356 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1357 			     MIPS_CPU_LLSC;
1358 		c->tlbsize = 48;
1359 		break;
1360 	case PRID_IMP_R5432:
1361 		c->cputype = CPU_R5432;
1362 		__cpu_name[cpu] = "R5432";
1363 		set_isa(c, MIPS_CPU_ISA_IV);
1364 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1365 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1366 		c->tlbsize = 48;
1367 		break;
1368 	case PRID_IMP_R5500:
1369 		c->cputype = CPU_R5500;
1370 		__cpu_name[cpu] = "R5500";
1371 		set_isa(c, MIPS_CPU_ISA_IV);
1372 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1373 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1374 		c->tlbsize = 48;
1375 		break;
1376 	case PRID_IMP_NEVADA:
1377 		c->cputype = CPU_NEVADA;
1378 		__cpu_name[cpu] = "Nevada";
1379 		set_isa(c, MIPS_CPU_ISA_IV);
1380 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1381 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1382 		c->tlbsize = 48;
1383 		break;
1384 	case PRID_IMP_R6000:
1385 		c->cputype = CPU_R6000;
1386 		__cpu_name[cpu] = "R6000";
1387 		set_isa(c, MIPS_CPU_ISA_II);
1388 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1389 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
1390 			     MIPS_CPU_LLSC;
1391 		c->tlbsize = 32;
1392 		break;
1393 	case PRID_IMP_R6000A:
1394 		c->cputype = CPU_R6000A;
1395 		__cpu_name[cpu] = "R6000A";
1396 		set_isa(c, MIPS_CPU_ISA_II);
1397 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1398 		c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
1399 			     MIPS_CPU_LLSC;
1400 		c->tlbsize = 32;
1401 		break;
1402 	case PRID_IMP_RM7000:
1403 		c->cputype = CPU_RM7000;
1404 		__cpu_name[cpu] = "RM7000";
1405 		set_isa(c, MIPS_CPU_ISA_IV);
1406 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1407 			     MIPS_CPU_LLSC;
1408 		/*
1409 		 * Undocumented RM7000:	 Bit 29 in the info register of
1410 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1411 		 * entries.
1412 		 *
1413 		 * 29	   1 =>	   64 entry JTLB
1414 		 *	   0 =>	   48 entry JTLB
1415 		 */
1416 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1417 		break;
1418 	case PRID_IMP_R8000:
1419 		c->cputype = CPU_R8000;
1420 		__cpu_name[cpu] = "RM8000";
1421 		set_isa(c, MIPS_CPU_ISA_IV);
1422 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
1423 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1424 			     MIPS_CPU_LLSC;
1425 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
1426 		break;
1427 	case PRID_IMP_R10000:
1428 		c->cputype = CPU_R10000;
1429 		__cpu_name[cpu] = "R10000";
1430 		set_isa(c, MIPS_CPU_ISA_IV);
1431 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1432 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1433 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1434 			     MIPS_CPU_LLSC;
1435 		c->tlbsize = 64;
1436 		break;
1437 	case PRID_IMP_R12000:
1438 		c->cputype = CPU_R12000;
1439 		__cpu_name[cpu] = "R12000";
1440 		set_isa(c, MIPS_CPU_ISA_IV);
1441 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1442 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1443 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1444 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1445 		c->tlbsize = 64;
1446 		break;
1447 	case PRID_IMP_R14000:
1448 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1449 			c->cputype = CPU_R16000;
1450 			__cpu_name[cpu] = "R16000";
1451 		} else {
1452 			c->cputype = CPU_R14000;
1453 			__cpu_name[cpu] = "R14000";
1454 		}
1455 		set_isa(c, MIPS_CPU_ISA_IV);
1456 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1457 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1458 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1459 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1460 		c->tlbsize = 64;
1461 		break;
1462 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1463 		switch (c->processor_id & PRID_REV_MASK) {
1464 		case PRID_REV_LOONGSON2E:
1465 			c->cputype = CPU_LOONGSON2;
1466 			__cpu_name[cpu] = "ICT Loongson-2";
1467 			set_elf_platform(cpu, "loongson2e");
1468 			set_isa(c, MIPS_CPU_ISA_III);
1469 			c->fpu_msk31 |= FPU_CSR_CONDX;
1470 			break;
1471 		case PRID_REV_LOONGSON2F:
1472 			c->cputype = CPU_LOONGSON2;
1473 			__cpu_name[cpu] = "ICT Loongson-2";
1474 			set_elf_platform(cpu, "loongson2f");
1475 			set_isa(c, MIPS_CPU_ISA_III);
1476 			c->fpu_msk31 |= FPU_CSR_CONDX;
1477 			break;
1478 		case PRID_REV_LOONGSON3A_R1:
1479 			c->cputype = CPU_LOONGSON3;
1480 			__cpu_name[cpu] = "ICT Loongson-3";
1481 			set_elf_platform(cpu, "loongson3a");
1482 			set_isa(c, MIPS_CPU_ISA_M64R1);
1483 			break;
1484 		case PRID_REV_LOONGSON3B_R1:
1485 		case PRID_REV_LOONGSON3B_R2:
1486 			c->cputype = CPU_LOONGSON3;
1487 			__cpu_name[cpu] = "ICT Loongson-3";
1488 			set_elf_platform(cpu, "loongson3b");
1489 			set_isa(c, MIPS_CPU_ISA_M64R1);
1490 			break;
1491 		}
1492 
1493 		c->options = R4K_OPTS |
1494 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1495 			     MIPS_CPU_32FPR;
1496 		c->tlbsize = 64;
1497 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1498 		break;
1499 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1500 		decode_configs(c);
1501 
1502 		c->cputype = CPU_LOONGSON1;
1503 
1504 		switch (c->processor_id & PRID_REV_MASK) {
1505 		case PRID_REV_LOONGSON1B:
1506 			__cpu_name[cpu] = "Loongson 1B";
1507 			break;
1508 		}
1509 
1510 		break;
1511 	}
1512 }
1513 
1514 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1515 {
1516 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1517 	switch (c->processor_id & PRID_IMP_MASK) {
1518 	case PRID_IMP_QEMU_GENERIC:
1519 		c->writecombine = _CACHE_UNCACHED;
1520 		c->cputype = CPU_QEMU_GENERIC;
1521 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1522 		break;
1523 	case PRID_IMP_4KC:
1524 		c->cputype = CPU_4KC;
1525 		c->writecombine = _CACHE_UNCACHED;
1526 		__cpu_name[cpu] = "MIPS 4Kc";
1527 		break;
1528 	case PRID_IMP_4KEC:
1529 	case PRID_IMP_4KECR2:
1530 		c->cputype = CPU_4KEC;
1531 		c->writecombine = _CACHE_UNCACHED;
1532 		__cpu_name[cpu] = "MIPS 4KEc";
1533 		break;
1534 	case PRID_IMP_4KSC:
1535 	case PRID_IMP_4KSD:
1536 		c->cputype = CPU_4KSC;
1537 		c->writecombine = _CACHE_UNCACHED;
1538 		__cpu_name[cpu] = "MIPS 4KSc";
1539 		break;
1540 	case PRID_IMP_5KC:
1541 		c->cputype = CPU_5KC;
1542 		c->writecombine = _CACHE_UNCACHED;
1543 		__cpu_name[cpu] = "MIPS 5Kc";
1544 		break;
1545 	case PRID_IMP_5KE:
1546 		c->cputype = CPU_5KE;
1547 		c->writecombine = _CACHE_UNCACHED;
1548 		__cpu_name[cpu] = "MIPS 5KE";
1549 		break;
1550 	case PRID_IMP_20KC:
1551 		c->cputype = CPU_20KC;
1552 		c->writecombine = _CACHE_UNCACHED;
1553 		__cpu_name[cpu] = "MIPS 20Kc";
1554 		break;
1555 	case PRID_IMP_24K:
1556 		c->cputype = CPU_24K;
1557 		c->writecombine = _CACHE_UNCACHED;
1558 		__cpu_name[cpu] = "MIPS 24Kc";
1559 		break;
1560 	case PRID_IMP_24KE:
1561 		c->cputype = CPU_24K;
1562 		c->writecombine = _CACHE_UNCACHED;
1563 		__cpu_name[cpu] = "MIPS 24KEc";
1564 		break;
1565 	case PRID_IMP_25KF:
1566 		c->cputype = CPU_25KF;
1567 		c->writecombine = _CACHE_UNCACHED;
1568 		__cpu_name[cpu] = "MIPS 25Kc";
1569 		break;
1570 	case PRID_IMP_34K:
1571 		c->cputype = CPU_34K;
1572 		c->writecombine = _CACHE_UNCACHED;
1573 		__cpu_name[cpu] = "MIPS 34Kc";
1574 		break;
1575 	case PRID_IMP_74K:
1576 		c->cputype = CPU_74K;
1577 		c->writecombine = _CACHE_UNCACHED;
1578 		__cpu_name[cpu] = "MIPS 74Kc";
1579 		break;
1580 	case PRID_IMP_M14KC:
1581 		c->cputype = CPU_M14KC;
1582 		c->writecombine = _CACHE_UNCACHED;
1583 		__cpu_name[cpu] = "MIPS M14Kc";
1584 		break;
1585 	case PRID_IMP_M14KEC:
1586 		c->cputype = CPU_M14KEC;
1587 		c->writecombine = _CACHE_UNCACHED;
1588 		__cpu_name[cpu] = "MIPS M14KEc";
1589 		break;
1590 	case PRID_IMP_1004K:
1591 		c->cputype = CPU_1004K;
1592 		c->writecombine = _CACHE_UNCACHED;
1593 		__cpu_name[cpu] = "MIPS 1004Kc";
1594 		break;
1595 	case PRID_IMP_1074K:
1596 		c->cputype = CPU_1074K;
1597 		c->writecombine = _CACHE_UNCACHED;
1598 		__cpu_name[cpu] = "MIPS 1074Kc";
1599 		break;
1600 	case PRID_IMP_INTERAPTIV_UP:
1601 		c->cputype = CPU_INTERAPTIV;
1602 		__cpu_name[cpu] = "MIPS interAptiv";
1603 		break;
1604 	case PRID_IMP_INTERAPTIV_MP:
1605 		c->cputype = CPU_INTERAPTIV;
1606 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1607 		break;
1608 	case PRID_IMP_PROAPTIV_UP:
1609 		c->cputype = CPU_PROAPTIV;
1610 		__cpu_name[cpu] = "MIPS proAptiv";
1611 		break;
1612 	case PRID_IMP_PROAPTIV_MP:
1613 		c->cputype = CPU_PROAPTIV;
1614 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1615 		break;
1616 	case PRID_IMP_P5600:
1617 		c->cputype = CPU_P5600;
1618 		__cpu_name[cpu] = "MIPS P5600";
1619 		break;
1620 	case PRID_IMP_P6600:
1621 		c->cputype = CPU_P6600;
1622 		__cpu_name[cpu] = "MIPS P6600";
1623 		break;
1624 	case PRID_IMP_I6400:
1625 		c->cputype = CPU_I6400;
1626 		__cpu_name[cpu] = "MIPS I6400";
1627 		break;
1628 	case PRID_IMP_M5150:
1629 		c->cputype = CPU_M5150;
1630 		__cpu_name[cpu] = "MIPS M5150";
1631 		break;
1632 	case PRID_IMP_M6250:
1633 		c->cputype = CPU_M6250;
1634 		__cpu_name[cpu] = "MIPS M6250";
1635 		break;
1636 	}
1637 
1638 	decode_configs(c);
1639 
1640 	spram_config();
1641 }
1642 
1643 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1644 {
1645 	decode_configs(c);
1646 	switch (c->processor_id & PRID_IMP_MASK) {
1647 	case PRID_IMP_AU1_REV1:
1648 	case PRID_IMP_AU1_REV2:
1649 		c->cputype = CPU_ALCHEMY;
1650 		switch ((c->processor_id >> 24) & 0xff) {
1651 		case 0:
1652 			__cpu_name[cpu] = "Au1000";
1653 			break;
1654 		case 1:
1655 			__cpu_name[cpu] = "Au1500";
1656 			break;
1657 		case 2:
1658 			__cpu_name[cpu] = "Au1100";
1659 			break;
1660 		case 3:
1661 			__cpu_name[cpu] = "Au1550";
1662 			break;
1663 		case 4:
1664 			__cpu_name[cpu] = "Au1200";
1665 			if ((c->processor_id & PRID_REV_MASK) == 2)
1666 				__cpu_name[cpu] = "Au1250";
1667 			break;
1668 		case 5:
1669 			__cpu_name[cpu] = "Au1210";
1670 			break;
1671 		default:
1672 			__cpu_name[cpu] = "Au1xxx";
1673 			break;
1674 		}
1675 		break;
1676 	}
1677 }
1678 
1679 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1680 {
1681 	decode_configs(c);
1682 
1683 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1684 	switch (c->processor_id & PRID_IMP_MASK) {
1685 	case PRID_IMP_SB1:
1686 		c->cputype = CPU_SB1;
1687 		__cpu_name[cpu] = "SiByte SB1";
1688 		/* FPU in pass1 is known to have issues. */
1689 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1690 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1691 		break;
1692 	case PRID_IMP_SB1A:
1693 		c->cputype = CPU_SB1A;
1694 		__cpu_name[cpu] = "SiByte SB1A";
1695 		break;
1696 	}
1697 }
1698 
1699 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1700 {
1701 	decode_configs(c);
1702 	switch (c->processor_id & PRID_IMP_MASK) {
1703 	case PRID_IMP_SR71000:
1704 		c->cputype = CPU_SR71000;
1705 		__cpu_name[cpu] = "Sandcraft SR71000";
1706 		c->scache.ways = 8;
1707 		c->tlbsize = 64;
1708 		break;
1709 	}
1710 }
1711 
1712 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1713 {
1714 	decode_configs(c);
1715 	switch (c->processor_id & PRID_IMP_MASK) {
1716 	case PRID_IMP_PR4450:
1717 		c->cputype = CPU_PR4450;
1718 		__cpu_name[cpu] = "Philips PR4450";
1719 		set_isa(c, MIPS_CPU_ISA_M32R1);
1720 		break;
1721 	}
1722 }
1723 
1724 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1725 {
1726 	decode_configs(c);
1727 	switch (c->processor_id & PRID_IMP_MASK) {
1728 	case PRID_IMP_BMIPS32_REV4:
1729 	case PRID_IMP_BMIPS32_REV8:
1730 		c->cputype = CPU_BMIPS32;
1731 		__cpu_name[cpu] = "Broadcom BMIPS32";
1732 		set_elf_platform(cpu, "bmips32");
1733 		break;
1734 	case PRID_IMP_BMIPS3300:
1735 	case PRID_IMP_BMIPS3300_ALT:
1736 	case PRID_IMP_BMIPS3300_BUG:
1737 		c->cputype = CPU_BMIPS3300;
1738 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1739 		set_elf_platform(cpu, "bmips3300");
1740 		break;
1741 	case PRID_IMP_BMIPS43XX: {
1742 		int rev = c->processor_id & PRID_REV_MASK;
1743 
1744 		if (rev >= PRID_REV_BMIPS4380_LO &&
1745 				rev <= PRID_REV_BMIPS4380_HI) {
1746 			c->cputype = CPU_BMIPS4380;
1747 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1748 			set_elf_platform(cpu, "bmips4380");
1749 			c->options |= MIPS_CPU_RIXI;
1750 		} else {
1751 			c->cputype = CPU_BMIPS4350;
1752 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1753 			set_elf_platform(cpu, "bmips4350");
1754 		}
1755 		break;
1756 	}
1757 	case PRID_IMP_BMIPS5000:
1758 	case PRID_IMP_BMIPS5200:
1759 		c->cputype = CPU_BMIPS5000;
1760 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1761 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1762 		else
1763 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1764 		set_elf_platform(cpu, "bmips5000");
1765 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1766 		break;
1767 	}
1768 }
1769 
1770 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1771 {
1772 	decode_configs(c);
1773 	switch (c->processor_id & PRID_IMP_MASK) {
1774 	case PRID_IMP_CAVIUM_CN38XX:
1775 	case PRID_IMP_CAVIUM_CN31XX:
1776 	case PRID_IMP_CAVIUM_CN30XX:
1777 		c->cputype = CPU_CAVIUM_OCTEON;
1778 		__cpu_name[cpu] = "Cavium Octeon";
1779 		goto platform;
1780 	case PRID_IMP_CAVIUM_CN58XX:
1781 	case PRID_IMP_CAVIUM_CN56XX:
1782 	case PRID_IMP_CAVIUM_CN50XX:
1783 	case PRID_IMP_CAVIUM_CN52XX:
1784 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1785 		__cpu_name[cpu] = "Cavium Octeon+";
1786 platform:
1787 		set_elf_platform(cpu, "octeon");
1788 		break;
1789 	case PRID_IMP_CAVIUM_CN61XX:
1790 	case PRID_IMP_CAVIUM_CN63XX:
1791 	case PRID_IMP_CAVIUM_CN66XX:
1792 	case PRID_IMP_CAVIUM_CN68XX:
1793 	case PRID_IMP_CAVIUM_CNF71XX:
1794 		c->cputype = CPU_CAVIUM_OCTEON2;
1795 		__cpu_name[cpu] = "Cavium Octeon II";
1796 		set_elf_platform(cpu, "octeon2");
1797 		break;
1798 	case PRID_IMP_CAVIUM_CN70XX:
1799 	case PRID_IMP_CAVIUM_CN73XX:
1800 	case PRID_IMP_CAVIUM_CNF75XX:
1801 	case PRID_IMP_CAVIUM_CN78XX:
1802 		c->cputype = CPU_CAVIUM_OCTEON3;
1803 		__cpu_name[cpu] = "Cavium Octeon III";
1804 		set_elf_platform(cpu, "octeon3");
1805 		break;
1806 	default:
1807 		printk(KERN_INFO "Unknown Octeon chip!\n");
1808 		c->cputype = CPU_UNKNOWN;
1809 		break;
1810 	}
1811 }
1812 
1813 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
1814 {
1815 	switch (c->processor_id & PRID_IMP_MASK) {
1816 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1817 		switch (c->processor_id & PRID_REV_MASK) {
1818 		case PRID_REV_LOONGSON3A_R2:
1819 			c->cputype = CPU_LOONGSON3;
1820 			__cpu_name[cpu] = "ICT Loongson-3";
1821 			set_elf_platform(cpu, "loongson3a");
1822 			set_isa(c, MIPS_CPU_ISA_M64R2);
1823 			break;
1824 		}
1825 
1826 		decode_configs(c);
1827 		c->options |= MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
1828 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1829 		break;
1830 	default:
1831 		panic("Unknown Loongson Processor ID!");
1832 		break;
1833 	}
1834 }
1835 
1836 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1837 {
1838 	decode_configs(c);
1839 	/* JZRISC does not implement the CP0 counter. */
1840 	c->options &= ~MIPS_CPU_COUNTER;
1841 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
1842 	switch (c->processor_id & PRID_IMP_MASK) {
1843 	case PRID_IMP_JZRISC:
1844 		c->cputype = CPU_JZRISC;
1845 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1846 		__cpu_name[cpu] = "Ingenic JZRISC";
1847 		break;
1848 	default:
1849 		panic("Unknown Ingenic Processor ID!");
1850 		break;
1851 	}
1852 }
1853 
1854 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1855 {
1856 	decode_configs(c);
1857 
1858 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1859 		c->cputype = CPU_ALCHEMY;
1860 		__cpu_name[cpu] = "Au1300";
1861 		/* following stuff is not for Alchemy */
1862 		return;
1863 	}
1864 
1865 	c->options = (MIPS_CPU_TLB	 |
1866 			MIPS_CPU_4KEX	 |
1867 			MIPS_CPU_COUNTER |
1868 			MIPS_CPU_DIVEC	 |
1869 			MIPS_CPU_WATCH	 |
1870 			MIPS_CPU_EJTAG	 |
1871 			MIPS_CPU_LLSC);
1872 
1873 	switch (c->processor_id & PRID_IMP_MASK) {
1874 	case PRID_IMP_NETLOGIC_XLP2XX:
1875 	case PRID_IMP_NETLOGIC_XLP9XX:
1876 	case PRID_IMP_NETLOGIC_XLP5XX:
1877 		c->cputype = CPU_XLP;
1878 		__cpu_name[cpu] = "Broadcom XLPII";
1879 		break;
1880 
1881 	case PRID_IMP_NETLOGIC_XLP8XX:
1882 	case PRID_IMP_NETLOGIC_XLP3XX:
1883 		c->cputype = CPU_XLP;
1884 		__cpu_name[cpu] = "Netlogic XLP";
1885 		break;
1886 
1887 	case PRID_IMP_NETLOGIC_XLR732:
1888 	case PRID_IMP_NETLOGIC_XLR716:
1889 	case PRID_IMP_NETLOGIC_XLR532:
1890 	case PRID_IMP_NETLOGIC_XLR308:
1891 	case PRID_IMP_NETLOGIC_XLR532C:
1892 	case PRID_IMP_NETLOGIC_XLR516C:
1893 	case PRID_IMP_NETLOGIC_XLR508C:
1894 	case PRID_IMP_NETLOGIC_XLR308C:
1895 		c->cputype = CPU_XLR;
1896 		__cpu_name[cpu] = "Netlogic XLR";
1897 		break;
1898 
1899 	case PRID_IMP_NETLOGIC_XLS608:
1900 	case PRID_IMP_NETLOGIC_XLS408:
1901 	case PRID_IMP_NETLOGIC_XLS404:
1902 	case PRID_IMP_NETLOGIC_XLS208:
1903 	case PRID_IMP_NETLOGIC_XLS204:
1904 	case PRID_IMP_NETLOGIC_XLS108:
1905 	case PRID_IMP_NETLOGIC_XLS104:
1906 	case PRID_IMP_NETLOGIC_XLS616B:
1907 	case PRID_IMP_NETLOGIC_XLS608B:
1908 	case PRID_IMP_NETLOGIC_XLS416B:
1909 	case PRID_IMP_NETLOGIC_XLS412B:
1910 	case PRID_IMP_NETLOGIC_XLS408B:
1911 	case PRID_IMP_NETLOGIC_XLS404B:
1912 		c->cputype = CPU_XLR;
1913 		__cpu_name[cpu] = "Netlogic XLS";
1914 		break;
1915 
1916 	default:
1917 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1918 		       c->processor_id);
1919 		c->cputype = CPU_XLR;
1920 		break;
1921 	}
1922 
1923 	if (c->cputype == CPU_XLP) {
1924 		set_isa(c, MIPS_CPU_ISA_M64R2);
1925 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1926 		/* This will be updated again after all threads are woken up */
1927 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1928 	} else {
1929 		set_isa(c, MIPS_CPU_ISA_M64R1);
1930 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1931 	}
1932 	c->kscratch_mask = 0xf;
1933 }
1934 
1935 #ifdef CONFIG_64BIT
1936 /* For use by uaccess.h */
1937 u64 __ua_limit;
1938 EXPORT_SYMBOL(__ua_limit);
1939 #endif
1940 
1941 const char *__cpu_name[NR_CPUS];
1942 const char *__elf_platform;
1943 
1944 void cpu_probe(void)
1945 {
1946 	struct cpuinfo_mips *c = &current_cpu_data;
1947 	unsigned int cpu = smp_processor_id();
1948 
1949 	c->processor_id = PRID_IMP_UNKNOWN;
1950 	c->fpu_id	= FPIR_IMP_NONE;
1951 	c->cputype	= CPU_UNKNOWN;
1952 	c->writecombine = _CACHE_UNCACHED;
1953 
1954 	c->fpu_csr31	= FPU_CSR_RN;
1955 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
1956 
1957 	c->processor_id = read_c0_prid();
1958 	switch (c->processor_id & PRID_COMP_MASK) {
1959 	case PRID_COMP_LEGACY:
1960 		cpu_probe_legacy(c, cpu);
1961 		break;
1962 	case PRID_COMP_MIPS:
1963 		cpu_probe_mips(c, cpu);
1964 		break;
1965 	case PRID_COMP_ALCHEMY:
1966 		cpu_probe_alchemy(c, cpu);
1967 		break;
1968 	case PRID_COMP_SIBYTE:
1969 		cpu_probe_sibyte(c, cpu);
1970 		break;
1971 	case PRID_COMP_BROADCOM:
1972 		cpu_probe_broadcom(c, cpu);
1973 		break;
1974 	case PRID_COMP_SANDCRAFT:
1975 		cpu_probe_sandcraft(c, cpu);
1976 		break;
1977 	case PRID_COMP_NXP:
1978 		cpu_probe_nxp(c, cpu);
1979 		break;
1980 	case PRID_COMP_CAVIUM:
1981 		cpu_probe_cavium(c, cpu);
1982 		break;
1983 	case PRID_COMP_LOONGSON:
1984 		cpu_probe_loongson(c, cpu);
1985 		break;
1986 	case PRID_COMP_INGENIC_D0:
1987 	case PRID_COMP_INGENIC_D1:
1988 	case PRID_COMP_INGENIC_E1:
1989 		cpu_probe_ingenic(c, cpu);
1990 		break;
1991 	case PRID_COMP_NETLOGIC:
1992 		cpu_probe_netlogic(c, cpu);
1993 		break;
1994 	}
1995 
1996 	BUG_ON(!__cpu_name[cpu]);
1997 	BUG_ON(c->cputype == CPU_UNKNOWN);
1998 
1999 	/*
2000 	 * Platform code can force the cpu type to optimize code
2001 	 * generation. In that case be sure the cpu type is correctly
2002 	 * manually setup otherwise it could trigger some nasty bugs.
2003 	 */
2004 	BUG_ON(current_cpu_type() != c->cputype);
2005 
2006 	if (cpu_has_rixi) {
2007 		/* Enable the RIXI exceptions */
2008 		set_c0_pagegrain(PG_IEC);
2009 		back_to_back_c0_hazard();
2010 		/* Verify the IEC bit is set */
2011 		if (read_c0_pagegrain() & PG_IEC)
2012 			c->options |= MIPS_CPU_RIXIEX;
2013 	}
2014 
2015 	if (mips_fpu_disabled)
2016 		c->options &= ~MIPS_CPU_FPU;
2017 
2018 	if (mips_dsp_disabled)
2019 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2020 
2021 	if (mips_htw_disabled) {
2022 		c->options &= ~MIPS_CPU_HTW;
2023 		write_c0_pwctl(read_c0_pwctl() &
2024 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2025 	}
2026 
2027 	if (c->options & MIPS_CPU_FPU)
2028 		cpu_set_fpu_opts(c);
2029 	else
2030 		cpu_set_nofpu_opts(c);
2031 
2032 	if (cpu_has_bp_ghist)
2033 		write_c0_r10k_diag(read_c0_r10k_diag() |
2034 				   R10K_DIAG_E_GHIST);
2035 
2036 	if (cpu_has_mips_r2_r6) {
2037 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2038 		/* R2 has Performance Counter Interrupt indicator */
2039 		c->options |= MIPS_CPU_PCI;
2040 	}
2041 	else
2042 		c->srsets = 1;
2043 
2044 	if (cpu_has_mips_r6)
2045 		elf_hwcap |= HWCAP_MIPS_R6;
2046 
2047 	if (cpu_has_msa) {
2048 		c->msa_id = cpu_get_msa_id();
2049 		WARN(c->msa_id & MSA_IR_WRPF,
2050 		     "Vector register partitioning unimplemented!");
2051 		elf_hwcap |= HWCAP_MIPS_MSA;
2052 	}
2053 
2054 	if (cpu_has_vz)
2055 		cpu_probe_vz(c);
2056 
2057 	cpu_probe_vmbits(c);
2058 
2059 #ifdef CONFIG_64BIT
2060 	if (cpu == 0)
2061 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2062 #endif
2063 }
2064 
2065 void cpu_report(void)
2066 {
2067 	struct cpuinfo_mips *c = &current_cpu_data;
2068 
2069 	pr_info("CPU%d revision is: %08x (%s)\n",
2070 		smp_processor_id(), c->processor_id, cpu_name_string());
2071 	if (c->options & MIPS_CPU_FPU)
2072 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2073 	if (cpu_has_msa)
2074 		pr_info("MSA revision is: %08x\n", c->msa_id);
2075 }
2076