xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 612a462a)
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 static inline void check_errata(void)
419 {
420 	struct cpuinfo_mips *c = &current_cpu_data;
421 
422 	switch (current_cpu_type()) {
423 	case CPU_34K:
424 		/*
425 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
426 		 * This code only handles VPE0, any SMP/RTOS code
427 		 * making use of VPE1 will be responsable for that VPE.
428 		 */
429 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
430 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
431 		break;
432 	default:
433 		break;
434 	}
435 }
436 
437 void __init check_bugs32(void)
438 {
439 	check_errata();
440 }
441 
442 /*
443  * Probe whether cpu has config register by trying to play with
444  * alternate cache bit and see whether it matters.
445  * It's used by cpu_probe to distinguish between R3000A and R3081.
446  */
447 static inline int cpu_has_confreg(void)
448 {
449 #ifdef CONFIG_CPU_R3000
450 	extern unsigned long r3k_cache_size(unsigned long);
451 	unsigned long size1, size2;
452 	unsigned long cfg = read_c0_conf();
453 
454 	size1 = r3k_cache_size(ST0_ISC);
455 	write_c0_conf(cfg ^ R30XX_CONF_AC);
456 	size2 = r3k_cache_size(ST0_ISC);
457 	write_c0_conf(cfg);
458 	return size1 != size2;
459 #else
460 	return 0;
461 #endif
462 }
463 
464 static inline void set_elf_platform(int cpu, const char *plat)
465 {
466 	if (cpu == 0)
467 		__elf_platform = plat;
468 }
469 
470 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
471 {
472 #ifdef __NEED_VMBITS_PROBE
473 	write_c0_entryhi(0x3fffffffffffe000ULL);
474 	back_to_back_c0_hazard();
475 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
476 #endif
477 }
478 
479 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
480 {
481 	switch (isa) {
482 	case MIPS_CPU_ISA_M64R2:
483 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
484 	case MIPS_CPU_ISA_M64R1:
485 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
486 	case MIPS_CPU_ISA_V:
487 		c->isa_level |= MIPS_CPU_ISA_V;
488 	case MIPS_CPU_ISA_IV:
489 		c->isa_level |= MIPS_CPU_ISA_IV;
490 	case MIPS_CPU_ISA_III:
491 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
492 		break;
493 
494 	/* R6 incompatible with everything else */
495 	case MIPS_CPU_ISA_M64R6:
496 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
497 	case MIPS_CPU_ISA_M32R6:
498 		c->isa_level |= MIPS_CPU_ISA_M32R6;
499 		/* Break here so we don't add incompatible ISAs */
500 		break;
501 	case MIPS_CPU_ISA_M32R2:
502 		c->isa_level |= MIPS_CPU_ISA_M32R2;
503 	case MIPS_CPU_ISA_M32R1:
504 		c->isa_level |= MIPS_CPU_ISA_M32R1;
505 	case MIPS_CPU_ISA_II:
506 		c->isa_level |= MIPS_CPU_ISA_II;
507 		break;
508 	}
509 }
510 
511 static char unknown_isa[] = KERN_ERR \
512 	"Unsupported ISA type, c0.config0: %d.";
513 
514 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
515 {
516 
517 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
518 
519 	/*
520 	 * 0 = All TLBWR instructions go to FTLB
521 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
522 	 * FTLB and 1 goes to the VTLB.
523 	 * 2 = 7:1: As above with 7:1 ratio.
524 	 * 3 = 3:1: As above with 3:1 ratio.
525 	 *
526 	 * Use the linear midpoint as the probability threshold.
527 	 */
528 	if (probability >= 12)
529 		return 1;
530 	else if (probability >= 6)
531 		return 2;
532 	else
533 		/*
534 		 * So FTLB is less than 4 times bigger than VTLB.
535 		 * A 3:1 ratio can still be useful though.
536 		 */
537 		return 3;
538 }
539 
540 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
541 {
542 	unsigned int config;
543 
544 	/* It's implementation dependent how the FTLB can be enabled */
545 	switch (c->cputype) {
546 	case CPU_PROAPTIV:
547 	case CPU_P5600:
548 	case CPU_P6600:
549 		/* proAptiv & related cores use Config6 to enable the FTLB */
550 		config = read_c0_config6();
551 
552 		if (flags & FTLB_EN)
553 			config |= MIPS_CONF6_FTLBEN;
554 		else
555 			config &= ~MIPS_CONF6_FTLBEN;
556 
557 		if (flags & FTLB_SET_PROB) {
558 			config &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
559 			config |= calculate_ftlb_probability(c)
560 				  << MIPS_CONF6_FTLBP_SHIFT;
561 		}
562 
563 		write_c0_config6(config);
564 		back_to_back_c0_hazard();
565 		break;
566 	case CPU_I6400:
567 	case CPU_I6500:
568 		/* There's no way to disable the FTLB */
569 		if (!(flags & FTLB_EN))
570 			return 1;
571 		return 0;
572 	case CPU_LOONGSON3:
573 		/* Flush ITLB, DTLB, VTLB and FTLB */
574 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
575 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
576 		/* Loongson-3 cores use Config6 to enable the FTLB */
577 		config = read_c0_config6();
578 		if (flags & FTLB_EN)
579 			/* Enable FTLB */
580 			write_c0_config6(config & ~MIPS_CONF6_FTLBDIS);
581 		else
582 			/* Disable FTLB */
583 			write_c0_config6(config | MIPS_CONF6_FTLBDIS);
584 		break;
585 	default:
586 		return 1;
587 	}
588 
589 	return 0;
590 }
591 
592 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
593 {
594 	unsigned int config0;
595 	int isa, mt;
596 
597 	config0 = read_c0_config();
598 
599 	/*
600 	 * Look for Standard TLB or Dual VTLB and FTLB
601 	 */
602 	mt = config0 & MIPS_CONF_MT;
603 	if (mt == MIPS_CONF_MT_TLB)
604 		c->options |= MIPS_CPU_TLB;
605 	else if (mt == MIPS_CONF_MT_FTLB)
606 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
607 
608 	isa = (config0 & MIPS_CONF_AT) >> 13;
609 	switch (isa) {
610 	case 0:
611 		switch ((config0 & MIPS_CONF_AR) >> 10) {
612 		case 0:
613 			set_isa(c, MIPS_CPU_ISA_M32R1);
614 			break;
615 		case 1:
616 			set_isa(c, MIPS_CPU_ISA_M32R2);
617 			break;
618 		case 2:
619 			set_isa(c, MIPS_CPU_ISA_M32R6);
620 			break;
621 		default:
622 			goto unknown;
623 		}
624 		break;
625 	case 2:
626 		switch ((config0 & MIPS_CONF_AR) >> 10) {
627 		case 0:
628 			set_isa(c, MIPS_CPU_ISA_M64R1);
629 			break;
630 		case 1:
631 			set_isa(c, MIPS_CPU_ISA_M64R2);
632 			break;
633 		case 2:
634 			set_isa(c, MIPS_CPU_ISA_M64R6);
635 			break;
636 		default:
637 			goto unknown;
638 		}
639 		break;
640 	default:
641 		goto unknown;
642 	}
643 
644 	return config0 & MIPS_CONF_M;
645 
646 unknown:
647 	panic(unknown_isa, config0);
648 }
649 
650 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
651 {
652 	unsigned int config1;
653 
654 	config1 = read_c0_config1();
655 
656 	if (config1 & MIPS_CONF1_MD)
657 		c->ases |= MIPS_ASE_MDMX;
658 	if (config1 & MIPS_CONF1_PC)
659 		c->options |= MIPS_CPU_PERF;
660 	if (config1 & MIPS_CONF1_WR)
661 		c->options |= MIPS_CPU_WATCH;
662 	if (config1 & MIPS_CONF1_CA)
663 		c->ases |= MIPS_ASE_MIPS16;
664 	if (config1 & MIPS_CONF1_EP)
665 		c->options |= MIPS_CPU_EJTAG;
666 	if (config1 & MIPS_CONF1_FP) {
667 		c->options |= MIPS_CPU_FPU;
668 		c->options |= MIPS_CPU_32FPR;
669 	}
670 	if (cpu_has_tlb) {
671 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
672 		c->tlbsizevtlb = c->tlbsize;
673 		c->tlbsizeftlbsets = 0;
674 	}
675 
676 	return config1 & MIPS_CONF_M;
677 }
678 
679 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
680 {
681 	unsigned int config2;
682 
683 	config2 = read_c0_config2();
684 
685 	if (config2 & MIPS_CONF2_SL)
686 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
687 
688 	return config2 & MIPS_CONF_M;
689 }
690 
691 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
692 {
693 	unsigned int config3;
694 
695 	config3 = read_c0_config3();
696 
697 	if (config3 & MIPS_CONF3_SM) {
698 		c->ases |= MIPS_ASE_SMARTMIPS;
699 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
700 	}
701 	if (config3 & MIPS_CONF3_RXI)
702 		c->options |= MIPS_CPU_RIXI;
703 	if (config3 & MIPS_CONF3_CTXTC)
704 		c->options |= MIPS_CPU_CTXTC;
705 	if (config3 & MIPS_CONF3_DSP)
706 		c->ases |= MIPS_ASE_DSP;
707 	if (config3 & MIPS_CONF3_DSP2P) {
708 		c->ases |= MIPS_ASE_DSP2P;
709 		if (cpu_has_mips_r6)
710 			c->ases |= MIPS_ASE_DSP3;
711 	}
712 	if (config3 & MIPS_CONF3_VINT)
713 		c->options |= MIPS_CPU_VINT;
714 	if (config3 & MIPS_CONF3_VEIC)
715 		c->options |= MIPS_CPU_VEIC;
716 	if (config3 & MIPS_CONF3_LPA)
717 		c->options |= MIPS_CPU_LPA;
718 	if (config3 & MIPS_CONF3_MT)
719 		c->ases |= MIPS_ASE_MIPSMT;
720 	if (config3 & MIPS_CONF3_ULRI)
721 		c->options |= MIPS_CPU_ULRI;
722 	if (config3 & MIPS_CONF3_ISA)
723 		c->options |= MIPS_CPU_MICROMIPS;
724 	if (config3 & MIPS_CONF3_VZ)
725 		c->ases |= MIPS_ASE_VZ;
726 	if (config3 & MIPS_CONF3_SC)
727 		c->options |= MIPS_CPU_SEGMENTS;
728 	if (config3 & MIPS_CONF3_BI)
729 		c->options |= MIPS_CPU_BADINSTR;
730 	if (config3 & MIPS_CONF3_BP)
731 		c->options |= MIPS_CPU_BADINSTRP;
732 	if (config3 & MIPS_CONF3_MSA)
733 		c->ases |= MIPS_ASE_MSA;
734 	if (config3 & MIPS_CONF3_PW) {
735 		c->htw_seq = 0;
736 		c->options |= MIPS_CPU_HTW;
737 	}
738 	if (config3 & MIPS_CONF3_CDMM)
739 		c->options |= MIPS_CPU_CDMM;
740 	if (config3 & MIPS_CONF3_SP)
741 		c->options |= MIPS_CPU_SP;
742 
743 	return config3 & MIPS_CONF_M;
744 }
745 
746 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
747 {
748 	unsigned int config4;
749 	unsigned int newcf4;
750 	unsigned int mmuextdef;
751 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
752 	unsigned long asid_mask;
753 
754 	config4 = read_c0_config4();
755 
756 	if (cpu_has_tlb) {
757 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
758 			c->options |= MIPS_CPU_TLBINV;
759 
760 		/*
761 		 * R6 has dropped the MMUExtDef field from config4.
762 		 * On R6 the fields always describe the FTLB, and only if it is
763 		 * present according to Config.MT.
764 		 */
765 		if (!cpu_has_mips_r6)
766 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
767 		else if (cpu_has_ftlb)
768 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
769 		else
770 			mmuextdef = 0;
771 
772 		switch (mmuextdef) {
773 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
774 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
775 			c->tlbsizevtlb = c->tlbsize;
776 			break;
777 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
778 			c->tlbsizevtlb +=
779 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
780 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
781 			c->tlbsize = c->tlbsizevtlb;
782 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
783 			/* fall through */
784 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
785 			if (mips_ftlb_disabled)
786 				break;
787 			newcf4 = (config4 & ~ftlb_page) |
788 				(page_size_ftlb(mmuextdef) <<
789 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
790 			write_c0_config4(newcf4);
791 			back_to_back_c0_hazard();
792 			config4 = read_c0_config4();
793 			if (config4 != newcf4) {
794 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
795 				       PAGE_SIZE, config4);
796 				/* Switch FTLB off */
797 				set_ftlb_enable(c, 0);
798 				mips_ftlb_disabled = 1;
799 				break;
800 			}
801 			c->tlbsizeftlbsets = 1 <<
802 				((config4 & MIPS_CONF4_FTLBSETS) >>
803 				 MIPS_CONF4_FTLBSETS_SHIFT);
804 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
805 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
806 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
807 			mips_has_ftlb_configured = 1;
808 			break;
809 		}
810 	}
811 
812 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
813 				>> MIPS_CONF4_KSCREXIST_SHIFT;
814 
815 	asid_mask = MIPS_ENTRYHI_ASID;
816 	if (config4 & MIPS_CONF4_AE)
817 		asid_mask |= MIPS_ENTRYHI_ASIDX;
818 	set_cpu_asid_mask(c, asid_mask);
819 
820 	/*
821 	 * Warn if the computed ASID mask doesn't match the mask the kernel
822 	 * is built for. This may indicate either a serious problem or an
823 	 * easy optimisation opportunity, but either way should be addressed.
824 	 */
825 	WARN_ON(asid_mask != cpu_asid_mask(c));
826 
827 	return config4 & MIPS_CONF_M;
828 }
829 
830 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
831 {
832 	unsigned int config5;
833 
834 	config5 = read_c0_config5();
835 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
836 	write_c0_config5(config5);
837 
838 	if (config5 & MIPS_CONF5_EVA)
839 		c->options |= MIPS_CPU_EVA;
840 	if (config5 & MIPS_CONF5_MRP)
841 		c->options |= MIPS_CPU_MAAR;
842 	if (config5 & MIPS_CONF5_LLB)
843 		c->options |= MIPS_CPU_RW_LLB;
844 	if (config5 & MIPS_CONF5_MVH)
845 		c->options |= MIPS_CPU_MVH;
846 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
847 		c->options |= MIPS_CPU_VP;
848 	if (config5 & MIPS_CONF5_CA2)
849 		c->ases |= MIPS_ASE_MIPS16E2;
850 
851 	return config5 & MIPS_CONF_M;
852 }
853 
854 static void decode_configs(struct cpuinfo_mips *c)
855 {
856 	int ok;
857 
858 	/* MIPS32 or MIPS64 compliant CPU.  */
859 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
860 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
861 
862 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
863 
864 	/* Enable FTLB if present and not disabled */
865 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
866 
867 	ok = decode_config0(c);			/* Read Config registers.  */
868 	BUG_ON(!ok);				/* Arch spec violation!	 */
869 	if (ok)
870 		ok = decode_config1(c);
871 	if (ok)
872 		ok = decode_config2(c);
873 	if (ok)
874 		ok = decode_config3(c);
875 	if (ok)
876 		ok = decode_config4(c);
877 	if (ok)
878 		ok = decode_config5(c);
879 
880 	/* Probe the EBase.WG bit */
881 	if (cpu_has_mips_r2_r6) {
882 		u64 ebase;
883 		unsigned int status;
884 
885 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
886 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
887 					 : (s32)read_c0_ebase();
888 		if (ebase & MIPS_EBASE_WG) {
889 			/* WG bit already set, we can avoid the clumsy probe */
890 			c->options |= MIPS_CPU_EBASE_WG;
891 		} else {
892 			/* Its UNDEFINED to change EBase while BEV=0 */
893 			status = read_c0_status();
894 			write_c0_status(status | ST0_BEV);
895 			irq_enable_hazard();
896 			/*
897 			 * On pre-r6 cores, this may well clobber the upper bits
898 			 * of EBase. This is hard to avoid without potentially
899 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
900 			 */
901 			if (cpu_has_mips64r6)
902 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
903 			else
904 				write_c0_ebase(ebase | MIPS_EBASE_WG);
905 			back_to_back_c0_hazard();
906 			/* Restore BEV */
907 			write_c0_status(status);
908 			if (read_c0_ebase() & MIPS_EBASE_WG) {
909 				c->options |= MIPS_CPU_EBASE_WG;
910 				write_c0_ebase(ebase);
911 			}
912 		}
913 	}
914 
915 	/* configure the FTLB write probability */
916 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
917 
918 	mips_probe_watch_registers(c);
919 
920 #ifndef CONFIG_MIPS_CPS
921 	if (cpu_has_mips_r2_r6) {
922 		unsigned int core;
923 
924 		core = get_ebase_cpunum();
925 		if (cpu_has_mipsmt)
926 			core >>= fls(core_nvpes()) - 1;
927 		cpu_set_core(c, core);
928 	}
929 #endif
930 }
931 
932 /*
933  * Probe for certain guest capabilities by writing config bits and reading back.
934  * Finally write back the original value.
935  */
936 #define probe_gc0_config(name, maxconf, bits)				\
937 do {									\
938 	unsigned int tmp;						\
939 	tmp = read_gc0_##name();					\
940 	write_gc0_##name(tmp | (bits));					\
941 	back_to_back_c0_hazard();					\
942 	maxconf = read_gc0_##name();					\
943 	write_gc0_##name(tmp);						\
944 } while (0)
945 
946 /*
947  * Probe for dynamic guest capabilities by changing certain config bits and
948  * reading back to see if they change. Finally write back the original value.
949  */
950 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
951 do {									\
952 	maxconf = read_gc0_##name();					\
953 	write_gc0_##name(maxconf ^ (bits));				\
954 	back_to_back_c0_hazard();					\
955 	dynconf = maxconf ^ read_gc0_##name();				\
956 	write_gc0_##name(maxconf);					\
957 	maxconf |= dynconf;						\
958 } while (0)
959 
960 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
961 {
962 	unsigned int config0;
963 
964 	probe_gc0_config(config, config0, MIPS_CONF_M);
965 
966 	if (config0 & MIPS_CONF_M)
967 		c->guest.conf |= BIT(1);
968 	return config0 & MIPS_CONF_M;
969 }
970 
971 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
972 {
973 	unsigned int config1, config1_dyn;
974 
975 	probe_gc0_config_dyn(config1, config1, config1_dyn,
976 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
977 			     MIPS_CONF1_FP);
978 
979 	if (config1 & MIPS_CONF1_FP)
980 		c->guest.options |= MIPS_CPU_FPU;
981 	if (config1_dyn & MIPS_CONF1_FP)
982 		c->guest.options_dyn |= MIPS_CPU_FPU;
983 
984 	if (config1 & MIPS_CONF1_WR)
985 		c->guest.options |= MIPS_CPU_WATCH;
986 	if (config1_dyn & MIPS_CONF1_WR)
987 		c->guest.options_dyn |= MIPS_CPU_WATCH;
988 
989 	if (config1 & MIPS_CONF1_PC)
990 		c->guest.options |= MIPS_CPU_PERF;
991 	if (config1_dyn & MIPS_CONF1_PC)
992 		c->guest.options_dyn |= MIPS_CPU_PERF;
993 
994 	if (config1 & MIPS_CONF_M)
995 		c->guest.conf |= BIT(2);
996 	return config1 & MIPS_CONF_M;
997 }
998 
999 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
1000 {
1001 	unsigned int config2;
1002 
1003 	probe_gc0_config(config2, config2, MIPS_CONF_M);
1004 
1005 	if (config2 & MIPS_CONF_M)
1006 		c->guest.conf |= BIT(3);
1007 	return config2 & MIPS_CONF_M;
1008 }
1009 
1010 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
1011 {
1012 	unsigned int config3, config3_dyn;
1013 
1014 	probe_gc0_config_dyn(config3, config3, config3_dyn,
1015 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
1016 			     MIPS_CONF3_CTXTC);
1017 
1018 	if (config3 & MIPS_CONF3_CTXTC)
1019 		c->guest.options |= MIPS_CPU_CTXTC;
1020 	if (config3_dyn & MIPS_CONF3_CTXTC)
1021 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
1022 
1023 	if (config3 & MIPS_CONF3_PW)
1024 		c->guest.options |= MIPS_CPU_HTW;
1025 
1026 	if (config3 & MIPS_CONF3_ULRI)
1027 		c->guest.options |= MIPS_CPU_ULRI;
1028 
1029 	if (config3 & MIPS_CONF3_SC)
1030 		c->guest.options |= MIPS_CPU_SEGMENTS;
1031 
1032 	if (config3 & MIPS_CONF3_BI)
1033 		c->guest.options |= MIPS_CPU_BADINSTR;
1034 	if (config3 & MIPS_CONF3_BP)
1035 		c->guest.options |= MIPS_CPU_BADINSTRP;
1036 
1037 	if (config3 & MIPS_CONF3_MSA)
1038 		c->guest.ases |= MIPS_ASE_MSA;
1039 	if (config3_dyn & MIPS_CONF3_MSA)
1040 		c->guest.ases_dyn |= MIPS_ASE_MSA;
1041 
1042 	if (config3 & MIPS_CONF_M)
1043 		c->guest.conf |= BIT(4);
1044 	return config3 & MIPS_CONF_M;
1045 }
1046 
1047 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
1048 {
1049 	unsigned int config4;
1050 
1051 	probe_gc0_config(config4, config4,
1052 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
1053 
1054 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
1055 				>> MIPS_CONF4_KSCREXIST_SHIFT;
1056 
1057 	if (config4 & MIPS_CONF_M)
1058 		c->guest.conf |= BIT(5);
1059 	return config4 & MIPS_CONF_M;
1060 }
1061 
1062 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
1063 {
1064 	unsigned int config5, config5_dyn;
1065 
1066 	probe_gc0_config_dyn(config5, config5, config5_dyn,
1067 			 MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
1068 
1069 	if (config5 & MIPS_CONF5_MRP)
1070 		c->guest.options |= MIPS_CPU_MAAR;
1071 	if (config5_dyn & MIPS_CONF5_MRP)
1072 		c->guest.options_dyn |= MIPS_CPU_MAAR;
1073 
1074 	if (config5 & MIPS_CONF5_LLB)
1075 		c->guest.options |= MIPS_CPU_RW_LLB;
1076 
1077 	if (config5 & MIPS_CONF5_MVH)
1078 		c->guest.options |= MIPS_CPU_MVH;
1079 
1080 	if (config5 & MIPS_CONF_M)
1081 		c->guest.conf |= BIT(6);
1082 	return config5 & MIPS_CONF_M;
1083 }
1084 
1085 static inline void decode_guest_configs(struct cpuinfo_mips *c)
1086 {
1087 	unsigned int ok;
1088 
1089 	ok = decode_guest_config0(c);
1090 	if (ok)
1091 		ok = decode_guest_config1(c);
1092 	if (ok)
1093 		ok = decode_guest_config2(c);
1094 	if (ok)
1095 		ok = decode_guest_config3(c);
1096 	if (ok)
1097 		ok = decode_guest_config4(c);
1098 	if (ok)
1099 		decode_guest_config5(c);
1100 }
1101 
1102 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
1103 {
1104 	unsigned int guestctl0, temp;
1105 
1106 	guestctl0 = read_c0_guestctl0();
1107 
1108 	if (guestctl0 & MIPS_GCTL0_G0E)
1109 		c->options |= MIPS_CPU_GUESTCTL0EXT;
1110 	if (guestctl0 & MIPS_GCTL0_G1)
1111 		c->options |= MIPS_CPU_GUESTCTL1;
1112 	if (guestctl0 & MIPS_GCTL0_G2)
1113 		c->options |= MIPS_CPU_GUESTCTL2;
1114 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
1115 		c->options |= MIPS_CPU_GUESTID;
1116 
1117 		/*
1118 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
1119 		 * first, otherwise all data accesses will be fully virtualised
1120 		 * as if they were performed by guest mode.
1121 		 */
1122 		write_c0_guestctl1(0);
1123 		tlbw_use_hazard();
1124 
1125 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
1126 		back_to_back_c0_hazard();
1127 		temp = read_c0_guestctl0();
1128 
1129 		if (temp & MIPS_GCTL0_DRG) {
1130 			write_c0_guestctl0(guestctl0);
1131 			c->options |= MIPS_CPU_DRG;
1132 		}
1133 	}
1134 }
1135 
1136 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1137 {
1138 	if (cpu_has_guestid) {
1139 		/* determine the number of bits of GuestID available */
1140 		write_c0_guestctl1(MIPS_GCTL1_ID);
1141 		back_to_back_c0_hazard();
1142 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1143 						>> MIPS_GCTL1_ID_SHIFT;
1144 		write_c0_guestctl1(0);
1145 	}
1146 }
1147 
1148 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1149 {
1150 	/* determine the number of bits of GTOffset available */
1151 	write_c0_gtoffset(0xffffffff);
1152 	back_to_back_c0_hazard();
1153 	c->gtoffset_mask = read_c0_gtoffset();
1154 	write_c0_gtoffset(0);
1155 }
1156 
1157 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1158 {
1159 	cpu_probe_guestctl0(c);
1160 	if (cpu_has_guestctl1)
1161 		cpu_probe_guestctl1(c);
1162 
1163 	cpu_probe_gtoffset(c);
1164 
1165 	decode_guest_configs(c);
1166 }
1167 
1168 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1169 		| MIPS_CPU_COUNTER)
1170 
1171 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1172 {
1173 	switch (c->processor_id & PRID_IMP_MASK) {
1174 	case PRID_IMP_R2000:
1175 		c->cputype = CPU_R2000;
1176 		__cpu_name[cpu] = "R2000";
1177 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1178 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1179 			     MIPS_CPU_NOFPUEX;
1180 		if (__cpu_has_fpu())
1181 			c->options |= MIPS_CPU_FPU;
1182 		c->tlbsize = 64;
1183 		break;
1184 	case PRID_IMP_R3000:
1185 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1186 			if (cpu_has_confreg()) {
1187 				c->cputype = CPU_R3081E;
1188 				__cpu_name[cpu] = "R3081";
1189 			} else {
1190 				c->cputype = CPU_R3000A;
1191 				__cpu_name[cpu] = "R3000A";
1192 			}
1193 		} else {
1194 			c->cputype = CPU_R3000;
1195 			__cpu_name[cpu] = "R3000";
1196 		}
1197 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1198 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1199 			     MIPS_CPU_NOFPUEX;
1200 		if (__cpu_has_fpu())
1201 			c->options |= MIPS_CPU_FPU;
1202 		c->tlbsize = 64;
1203 		break;
1204 	case PRID_IMP_R4000:
1205 		if (read_c0_config() & CONF_SC) {
1206 			if ((c->processor_id & PRID_REV_MASK) >=
1207 			    PRID_REV_R4400) {
1208 				c->cputype = CPU_R4400PC;
1209 				__cpu_name[cpu] = "R4400PC";
1210 			} else {
1211 				c->cputype = CPU_R4000PC;
1212 				__cpu_name[cpu] = "R4000PC";
1213 			}
1214 		} else {
1215 			int cca = read_c0_config() & CONF_CM_CMASK;
1216 			int mc;
1217 
1218 			/*
1219 			 * SC and MC versions can't be reliably told apart,
1220 			 * but only the latter support coherent caching
1221 			 * modes so assume the firmware has set the KSEG0
1222 			 * coherency attribute reasonably (if uncached, we
1223 			 * assume SC).
1224 			 */
1225 			switch (cca) {
1226 			case CONF_CM_CACHABLE_CE:
1227 			case CONF_CM_CACHABLE_COW:
1228 			case CONF_CM_CACHABLE_CUW:
1229 				mc = 1;
1230 				break;
1231 			default:
1232 				mc = 0;
1233 				break;
1234 			}
1235 			if ((c->processor_id & PRID_REV_MASK) >=
1236 			    PRID_REV_R4400) {
1237 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1238 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1239 			} else {
1240 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1241 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1242 			}
1243 		}
1244 
1245 		set_isa(c, MIPS_CPU_ISA_III);
1246 		c->fpu_msk31 |= FPU_CSR_CONDX;
1247 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1248 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1249 			     MIPS_CPU_LLSC;
1250 		c->tlbsize = 48;
1251 		break;
1252 	case PRID_IMP_VR41XX:
1253 		set_isa(c, MIPS_CPU_ISA_III);
1254 		c->fpu_msk31 |= FPU_CSR_CONDX;
1255 		c->options = R4K_OPTS;
1256 		c->tlbsize = 32;
1257 		switch (c->processor_id & 0xf0) {
1258 		case PRID_REV_VR4111:
1259 			c->cputype = CPU_VR4111;
1260 			__cpu_name[cpu] = "NEC VR4111";
1261 			break;
1262 		case PRID_REV_VR4121:
1263 			c->cputype = CPU_VR4121;
1264 			__cpu_name[cpu] = "NEC VR4121";
1265 			break;
1266 		case PRID_REV_VR4122:
1267 			if ((c->processor_id & 0xf) < 0x3) {
1268 				c->cputype = CPU_VR4122;
1269 				__cpu_name[cpu] = "NEC VR4122";
1270 			} else {
1271 				c->cputype = CPU_VR4181A;
1272 				__cpu_name[cpu] = "NEC VR4181A";
1273 			}
1274 			break;
1275 		case PRID_REV_VR4130:
1276 			if ((c->processor_id & 0xf) < 0x4) {
1277 				c->cputype = CPU_VR4131;
1278 				__cpu_name[cpu] = "NEC VR4131";
1279 			} else {
1280 				c->cputype = CPU_VR4133;
1281 				c->options |= MIPS_CPU_LLSC;
1282 				__cpu_name[cpu] = "NEC VR4133";
1283 			}
1284 			break;
1285 		default:
1286 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1287 			c->cputype = CPU_VR41XX;
1288 			__cpu_name[cpu] = "NEC Vr41xx";
1289 			break;
1290 		}
1291 		break;
1292 	case PRID_IMP_R4300:
1293 		c->cputype = CPU_R4300;
1294 		__cpu_name[cpu] = "R4300";
1295 		set_isa(c, MIPS_CPU_ISA_III);
1296 		c->fpu_msk31 |= FPU_CSR_CONDX;
1297 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1298 			     MIPS_CPU_LLSC;
1299 		c->tlbsize = 32;
1300 		break;
1301 	case PRID_IMP_R4600:
1302 		c->cputype = CPU_R4600;
1303 		__cpu_name[cpu] = "R4600";
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_32FPR |
1307 			     MIPS_CPU_LLSC;
1308 		c->tlbsize = 48;
1309 		break;
1310 	#if 0
1311 	case PRID_IMP_R4650:
1312 		/*
1313 		 * This processor doesn't have an MMU, so it's not
1314 		 * "real easy" to run Linux on it. It is left purely
1315 		 * for documentation.  Commented out because it shares
1316 		 * it's c0_prid id number with the TX3900.
1317 		 */
1318 		c->cputype = CPU_R4650;
1319 		__cpu_name[cpu] = "R4650";
1320 		set_isa(c, MIPS_CPU_ISA_III);
1321 		c->fpu_msk31 |= FPU_CSR_CONDX;
1322 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1323 		c->tlbsize = 48;
1324 		break;
1325 	#endif
1326 	case PRID_IMP_TX39:
1327 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1328 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1329 
1330 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1331 			c->cputype = CPU_TX3927;
1332 			__cpu_name[cpu] = "TX3927";
1333 			c->tlbsize = 64;
1334 		} else {
1335 			switch (c->processor_id & PRID_REV_MASK) {
1336 			case PRID_REV_TX3912:
1337 				c->cputype = CPU_TX3912;
1338 				__cpu_name[cpu] = "TX3912";
1339 				c->tlbsize = 32;
1340 				break;
1341 			case PRID_REV_TX3922:
1342 				c->cputype = CPU_TX3922;
1343 				__cpu_name[cpu] = "TX3922";
1344 				c->tlbsize = 64;
1345 				break;
1346 			}
1347 		}
1348 		break;
1349 	case PRID_IMP_R4700:
1350 		c->cputype = CPU_R4700;
1351 		__cpu_name[cpu] = "R4700";
1352 		set_isa(c, MIPS_CPU_ISA_III);
1353 		c->fpu_msk31 |= FPU_CSR_CONDX;
1354 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1355 			     MIPS_CPU_LLSC;
1356 		c->tlbsize = 48;
1357 		break;
1358 	case PRID_IMP_TX49:
1359 		c->cputype = CPU_TX49XX;
1360 		__cpu_name[cpu] = "R49XX";
1361 		set_isa(c, MIPS_CPU_ISA_III);
1362 		c->fpu_msk31 |= FPU_CSR_CONDX;
1363 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1364 		if (!(c->processor_id & 0x08))
1365 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1366 		c->tlbsize = 48;
1367 		break;
1368 	case PRID_IMP_R5000:
1369 		c->cputype = CPU_R5000;
1370 		__cpu_name[cpu] = "R5000";
1371 		set_isa(c, MIPS_CPU_ISA_IV);
1372 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1373 			     MIPS_CPU_LLSC;
1374 		c->tlbsize = 48;
1375 		break;
1376 	case PRID_IMP_R5432:
1377 		c->cputype = CPU_R5432;
1378 		__cpu_name[cpu] = "R5432";
1379 		set_isa(c, MIPS_CPU_ISA_IV);
1380 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1381 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1382 		c->tlbsize = 48;
1383 		break;
1384 	case PRID_IMP_R5500:
1385 		c->cputype = CPU_R5500;
1386 		__cpu_name[cpu] = "R5500";
1387 		set_isa(c, MIPS_CPU_ISA_IV);
1388 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1389 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1390 		c->tlbsize = 48;
1391 		break;
1392 	case PRID_IMP_NEVADA:
1393 		c->cputype = CPU_NEVADA;
1394 		__cpu_name[cpu] = "Nevada";
1395 		set_isa(c, MIPS_CPU_ISA_IV);
1396 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1397 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1398 		c->tlbsize = 48;
1399 		break;
1400 	case PRID_IMP_RM7000:
1401 		c->cputype = CPU_RM7000;
1402 		__cpu_name[cpu] = "RM7000";
1403 		set_isa(c, MIPS_CPU_ISA_IV);
1404 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1405 			     MIPS_CPU_LLSC;
1406 		/*
1407 		 * Undocumented RM7000:	 Bit 29 in the info register of
1408 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1409 		 * entries.
1410 		 *
1411 		 * 29	   1 =>	   64 entry JTLB
1412 		 *	   0 =>	   48 entry JTLB
1413 		 */
1414 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1415 		break;
1416 	case PRID_IMP_R8000:
1417 		c->cputype = CPU_R8000;
1418 		__cpu_name[cpu] = "RM8000";
1419 		set_isa(c, MIPS_CPU_ISA_IV);
1420 		c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
1421 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1422 			     MIPS_CPU_LLSC;
1423 		c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
1424 		break;
1425 	case PRID_IMP_R10000:
1426 		c->cputype = CPU_R10000;
1427 		__cpu_name[cpu] = "R10000";
1428 		set_isa(c, MIPS_CPU_ISA_IV);
1429 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1430 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1431 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1432 			     MIPS_CPU_LLSC;
1433 		c->tlbsize = 64;
1434 		break;
1435 	case PRID_IMP_R12000:
1436 		c->cputype = CPU_R12000;
1437 		__cpu_name[cpu] = "R12000";
1438 		set_isa(c, MIPS_CPU_ISA_IV);
1439 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1440 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1441 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1442 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1443 		c->tlbsize = 64;
1444 		break;
1445 	case PRID_IMP_R14000:
1446 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1447 			c->cputype = CPU_R16000;
1448 			__cpu_name[cpu] = "R16000";
1449 		} else {
1450 			c->cputype = CPU_R14000;
1451 			__cpu_name[cpu] = "R14000";
1452 		}
1453 		set_isa(c, MIPS_CPU_ISA_IV);
1454 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1455 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1456 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1457 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1458 		c->tlbsize = 64;
1459 		break;
1460 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1461 		switch (c->processor_id & PRID_REV_MASK) {
1462 		case PRID_REV_LOONGSON2E:
1463 			c->cputype = CPU_LOONGSON2;
1464 			__cpu_name[cpu] = "ICT Loongson-2";
1465 			set_elf_platform(cpu, "loongson2e");
1466 			set_isa(c, MIPS_CPU_ISA_III);
1467 			c->fpu_msk31 |= FPU_CSR_CONDX;
1468 			break;
1469 		case PRID_REV_LOONGSON2F:
1470 			c->cputype = CPU_LOONGSON2;
1471 			__cpu_name[cpu] = "ICT Loongson-2";
1472 			set_elf_platform(cpu, "loongson2f");
1473 			set_isa(c, MIPS_CPU_ISA_III);
1474 			c->fpu_msk31 |= FPU_CSR_CONDX;
1475 			break;
1476 		case PRID_REV_LOONGSON3A_R1:
1477 			c->cputype = CPU_LOONGSON3;
1478 			__cpu_name[cpu] = "ICT Loongson-3";
1479 			set_elf_platform(cpu, "loongson3a");
1480 			set_isa(c, MIPS_CPU_ISA_M64R1);
1481 			break;
1482 		case PRID_REV_LOONGSON3B_R1:
1483 		case PRID_REV_LOONGSON3B_R2:
1484 			c->cputype = CPU_LOONGSON3;
1485 			__cpu_name[cpu] = "ICT Loongson-3";
1486 			set_elf_platform(cpu, "loongson3b");
1487 			set_isa(c, MIPS_CPU_ISA_M64R1);
1488 			break;
1489 		}
1490 
1491 		c->options = R4K_OPTS |
1492 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1493 			     MIPS_CPU_32FPR;
1494 		c->tlbsize = 64;
1495 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1496 		break;
1497 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1498 		decode_configs(c);
1499 
1500 		c->cputype = CPU_LOONGSON1;
1501 
1502 		switch (c->processor_id & PRID_REV_MASK) {
1503 		case PRID_REV_LOONGSON1B:
1504 			__cpu_name[cpu] = "Loongson 1B";
1505 			break;
1506 		}
1507 
1508 		break;
1509 	}
1510 }
1511 
1512 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1513 {
1514 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1515 	switch (c->processor_id & PRID_IMP_MASK) {
1516 	case PRID_IMP_QEMU_GENERIC:
1517 		c->writecombine = _CACHE_UNCACHED;
1518 		c->cputype = CPU_QEMU_GENERIC;
1519 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1520 		break;
1521 	case PRID_IMP_4KC:
1522 		c->cputype = CPU_4KC;
1523 		c->writecombine = _CACHE_UNCACHED;
1524 		__cpu_name[cpu] = "MIPS 4Kc";
1525 		break;
1526 	case PRID_IMP_4KEC:
1527 	case PRID_IMP_4KECR2:
1528 		c->cputype = CPU_4KEC;
1529 		c->writecombine = _CACHE_UNCACHED;
1530 		__cpu_name[cpu] = "MIPS 4KEc";
1531 		break;
1532 	case PRID_IMP_4KSC:
1533 	case PRID_IMP_4KSD:
1534 		c->cputype = CPU_4KSC;
1535 		c->writecombine = _CACHE_UNCACHED;
1536 		__cpu_name[cpu] = "MIPS 4KSc";
1537 		break;
1538 	case PRID_IMP_5KC:
1539 		c->cputype = CPU_5KC;
1540 		c->writecombine = _CACHE_UNCACHED;
1541 		__cpu_name[cpu] = "MIPS 5Kc";
1542 		break;
1543 	case PRID_IMP_5KE:
1544 		c->cputype = CPU_5KE;
1545 		c->writecombine = _CACHE_UNCACHED;
1546 		__cpu_name[cpu] = "MIPS 5KE";
1547 		break;
1548 	case PRID_IMP_20KC:
1549 		c->cputype = CPU_20KC;
1550 		c->writecombine = _CACHE_UNCACHED;
1551 		__cpu_name[cpu] = "MIPS 20Kc";
1552 		break;
1553 	case PRID_IMP_24K:
1554 		c->cputype = CPU_24K;
1555 		c->writecombine = _CACHE_UNCACHED;
1556 		__cpu_name[cpu] = "MIPS 24Kc";
1557 		break;
1558 	case PRID_IMP_24KE:
1559 		c->cputype = CPU_24K;
1560 		c->writecombine = _CACHE_UNCACHED;
1561 		__cpu_name[cpu] = "MIPS 24KEc";
1562 		break;
1563 	case PRID_IMP_25KF:
1564 		c->cputype = CPU_25KF;
1565 		c->writecombine = _CACHE_UNCACHED;
1566 		__cpu_name[cpu] = "MIPS 25Kc";
1567 		break;
1568 	case PRID_IMP_34K:
1569 		c->cputype = CPU_34K;
1570 		c->writecombine = _CACHE_UNCACHED;
1571 		__cpu_name[cpu] = "MIPS 34Kc";
1572 		break;
1573 	case PRID_IMP_74K:
1574 		c->cputype = CPU_74K;
1575 		c->writecombine = _CACHE_UNCACHED;
1576 		__cpu_name[cpu] = "MIPS 74Kc";
1577 		break;
1578 	case PRID_IMP_M14KC:
1579 		c->cputype = CPU_M14KC;
1580 		c->writecombine = _CACHE_UNCACHED;
1581 		__cpu_name[cpu] = "MIPS M14Kc";
1582 		break;
1583 	case PRID_IMP_M14KEC:
1584 		c->cputype = CPU_M14KEC;
1585 		c->writecombine = _CACHE_UNCACHED;
1586 		__cpu_name[cpu] = "MIPS M14KEc";
1587 		break;
1588 	case PRID_IMP_1004K:
1589 		c->cputype = CPU_1004K;
1590 		c->writecombine = _CACHE_UNCACHED;
1591 		__cpu_name[cpu] = "MIPS 1004Kc";
1592 		break;
1593 	case PRID_IMP_1074K:
1594 		c->cputype = CPU_1074K;
1595 		c->writecombine = _CACHE_UNCACHED;
1596 		__cpu_name[cpu] = "MIPS 1074Kc";
1597 		break;
1598 	case PRID_IMP_INTERAPTIV_UP:
1599 		c->cputype = CPU_INTERAPTIV;
1600 		__cpu_name[cpu] = "MIPS interAptiv";
1601 		break;
1602 	case PRID_IMP_INTERAPTIV_MP:
1603 		c->cputype = CPU_INTERAPTIV;
1604 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1605 		break;
1606 	case PRID_IMP_PROAPTIV_UP:
1607 		c->cputype = CPU_PROAPTIV;
1608 		__cpu_name[cpu] = "MIPS proAptiv";
1609 		break;
1610 	case PRID_IMP_PROAPTIV_MP:
1611 		c->cputype = CPU_PROAPTIV;
1612 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1613 		break;
1614 	case PRID_IMP_P5600:
1615 		c->cputype = CPU_P5600;
1616 		__cpu_name[cpu] = "MIPS P5600";
1617 		break;
1618 	case PRID_IMP_P6600:
1619 		c->cputype = CPU_P6600;
1620 		__cpu_name[cpu] = "MIPS P6600";
1621 		break;
1622 	case PRID_IMP_I6400:
1623 		c->cputype = CPU_I6400;
1624 		__cpu_name[cpu] = "MIPS I6400";
1625 		break;
1626 	case PRID_IMP_I6500:
1627 		c->cputype = CPU_I6500;
1628 		__cpu_name[cpu] = "MIPS I6500";
1629 		break;
1630 	case PRID_IMP_M5150:
1631 		c->cputype = CPU_M5150;
1632 		__cpu_name[cpu] = "MIPS M5150";
1633 		break;
1634 	case PRID_IMP_M6250:
1635 		c->cputype = CPU_M6250;
1636 		__cpu_name[cpu] = "MIPS M6250";
1637 		break;
1638 	}
1639 
1640 	decode_configs(c);
1641 
1642 	spram_config();
1643 
1644 	switch (__get_cpu_type(c->cputype)) {
1645 	case CPU_I6500:
1646 		c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
1647 		/* fall-through */
1648 	case CPU_I6400:
1649 		c->options |= MIPS_CPU_SHARED_FTLB_RAM;
1650 		/* fall-through */
1651 	default:
1652 		break;
1653 	}
1654 }
1655 
1656 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1657 {
1658 	decode_configs(c);
1659 	switch (c->processor_id & PRID_IMP_MASK) {
1660 	case PRID_IMP_AU1_REV1:
1661 	case PRID_IMP_AU1_REV2:
1662 		c->cputype = CPU_ALCHEMY;
1663 		switch ((c->processor_id >> 24) & 0xff) {
1664 		case 0:
1665 			__cpu_name[cpu] = "Au1000";
1666 			break;
1667 		case 1:
1668 			__cpu_name[cpu] = "Au1500";
1669 			break;
1670 		case 2:
1671 			__cpu_name[cpu] = "Au1100";
1672 			break;
1673 		case 3:
1674 			__cpu_name[cpu] = "Au1550";
1675 			break;
1676 		case 4:
1677 			__cpu_name[cpu] = "Au1200";
1678 			if ((c->processor_id & PRID_REV_MASK) == 2)
1679 				__cpu_name[cpu] = "Au1250";
1680 			break;
1681 		case 5:
1682 			__cpu_name[cpu] = "Au1210";
1683 			break;
1684 		default:
1685 			__cpu_name[cpu] = "Au1xxx";
1686 			break;
1687 		}
1688 		break;
1689 	}
1690 }
1691 
1692 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1693 {
1694 	decode_configs(c);
1695 
1696 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1697 	switch (c->processor_id & PRID_IMP_MASK) {
1698 	case PRID_IMP_SB1:
1699 		c->cputype = CPU_SB1;
1700 		__cpu_name[cpu] = "SiByte SB1";
1701 		/* FPU in pass1 is known to have issues. */
1702 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1703 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1704 		break;
1705 	case PRID_IMP_SB1A:
1706 		c->cputype = CPU_SB1A;
1707 		__cpu_name[cpu] = "SiByte SB1A";
1708 		break;
1709 	}
1710 }
1711 
1712 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1713 {
1714 	decode_configs(c);
1715 	switch (c->processor_id & PRID_IMP_MASK) {
1716 	case PRID_IMP_SR71000:
1717 		c->cputype = CPU_SR71000;
1718 		__cpu_name[cpu] = "Sandcraft SR71000";
1719 		c->scache.ways = 8;
1720 		c->tlbsize = 64;
1721 		break;
1722 	}
1723 }
1724 
1725 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1726 {
1727 	decode_configs(c);
1728 	switch (c->processor_id & PRID_IMP_MASK) {
1729 	case PRID_IMP_PR4450:
1730 		c->cputype = CPU_PR4450;
1731 		__cpu_name[cpu] = "Philips PR4450";
1732 		set_isa(c, MIPS_CPU_ISA_M32R1);
1733 		break;
1734 	}
1735 }
1736 
1737 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1738 {
1739 	decode_configs(c);
1740 	switch (c->processor_id & PRID_IMP_MASK) {
1741 	case PRID_IMP_BMIPS32_REV4:
1742 	case PRID_IMP_BMIPS32_REV8:
1743 		c->cputype = CPU_BMIPS32;
1744 		__cpu_name[cpu] = "Broadcom BMIPS32";
1745 		set_elf_platform(cpu, "bmips32");
1746 		break;
1747 	case PRID_IMP_BMIPS3300:
1748 	case PRID_IMP_BMIPS3300_ALT:
1749 	case PRID_IMP_BMIPS3300_BUG:
1750 		c->cputype = CPU_BMIPS3300;
1751 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1752 		set_elf_platform(cpu, "bmips3300");
1753 		break;
1754 	case PRID_IMP_BMIPS43XX: {
1755 		int rev = c->processor_id & PRID_REV_MASK;
1756 
1757 		if (rev >= PRID_REV_BMIPS4380_LO &&
1758 				rev <= PRID_REV_BMIPS4380_HI) {
1759 			c->cputype = CPU_BMIPS4380;
1760 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1761 			set_elf_platform(cpu, "bmips4380");
1762 			c->options |= MIPS_CPU_RIXI;
1763 		} else {
1764 			c->cputype = CPU_BMIPS4350;
1765 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1766 			set_elf_platform(cpu, "bmips4350");
1767 		}
1768 		break;
1769 	}
1770 	case PRID_IMP_BMIPS5000:
1771 	case PRID_IMP_BMIPS5200:
1772 		c->cputype = CPU_BMIPS5000;
1773 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1774 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1775 		else
1776 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1777 		set_elf_platform(cpu, "bmips5000");
1778 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1779 		break;
1780 	}
1781 }
1782 
1783 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1784 {
1785 	decode_configs(c);
1786 	switch (c->processor_id & PRID_IMP_MASK) {
1787 	case PRID_IMP_CAVIUM_CN38XX:
1788 	case PRID_IMP_CAVIUM_CN31XX:
1789 	case PRID_IMP_CAVIUM_CN30XX:
1790 		c->cputype = CPU_CAVIUM_OCTEON;
1791 		__cpu_name[cpu] = "Cavium Octeon";
1792 		goto platform;
1793 	case PRID_IMP_CAVIUM_CN58XX:
1794 	case PRID_IMP_CAVIUM_CN56XX:
1795 	case PRID_IMP_CAVIUM_CN50XX:
1796 	case PRID_IMP_CAVIUM_CN52XX:
1797 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1798 		__cpu_name[cpu] = "Cavium Octeon+";
1799 platform:
1800 		set_elf_platform(cpu, "octeon");
1801 		break;
1802 	case PRID_IMP_CAVIUM_CN61XX:
1803 	case PRID_IMP_CAVIUM_CN63XX:
1804 	case PRID_IMP_CAVIUM_CN66XX:
1805 	case PRID_IMP_CAVIUM_CN68XX:
1806 	case PRID_IMP_CAVIUM_CNF71XX:
1807 		c->cputype = CPU_CAVIUM_OCTEON2;
1808 		__cpu_name[cpu] = "Cavium Octeon II";
1809 		set_elf_platform(cpu, "octeon2");
1810 		break;
1811 	case PRID_IMP_CAVIUM_CN70XX:
1812 	case PRID_IMP_CAVIUM_CN73XX:
1813 	case PRID_IMP_CAVIUM_CNF75XX:
1814 	case PRID_IMP_CAVIUM_CN78XX:
1815 		c->cputype = CPU_CAVIUM_OCTEON3;
1816 		__cpu_name[cpu] = "Cavium Octeon III";
1817 		set_elf_platform(cpu, "octeon3");
1818 		break;
1819 	default:
1820 		printk(KERN_INFO "Unknown Octeon chip!\n");
1821 		c->cputype = CPU_UNKNOWN;
1822 		break;
1823 	}
1824 }
1825 
1826 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
1827 {
1828 	switch (c->processor_id & PRID_IMP_MASK) {
1829 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1830 		switch (c->processor_id & PRID_REV_MASK) {
1831 		case PRID_REV_LOONGSON3A_R2:
1832 			c->cputype = CPU_LOONGSON3;
1833 			__cpu_name[cpu] = "ICT Loongson-3";
1834 			set_elf_platform(cpu, "loongson3a");
1835 			set_isa(c, MIPS_CPU_ISA_M64R2);
1836 			break;
1837 		case PRID_REV_LOONGSON3A_R3:
1838 			c->cputype = CPU_LOONGSON3;
1839 			__cpu_name[cpu] = "ICT Loongson-3";
1840 			set_elf_platform(cpu, "loongson3a");
1841 			set_isa(c, MIPS_CPU_ISA_M64R2);
1842 			break;
1843 		}
1844 
1845 		decode_configs(c);
1846 		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
1847 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1848 		break;
1849 	default:
1850 		panic("Unknown Loongson Processor ID!");
1851 		break;
1852 	}
1853 }
1854 
1855 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1856 {
1857 	decode_configs(c);
1858 	/* JZRISC does not implement the CP0 counter. */
1859 	c->options &= ~MIPS_CPU_COUNTER;
1860 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
1861 	switch (c->processor_id & PRID_IMP_MASK) {
1862 	case PRID_IMP_JZRISC:
1863 		c->cputype = CPU_JZRISC;
1864 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1865 		__cpu_name[cpu] = "Ingenic JZRISC";
1866 		break;
1867 	default:
1868 		panic("Unknown Ingenic Processor ID!");
1869 		break;
1870 	}
1871 }
1872 
1873 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1874 {
1875 	decode_configs(c);
1876 
1877 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1878 		c->cputype = CPU_ALCHEMY;
1879 		__cpu_name[cpu] = "Au1300";
1880 		/* following stuff is not for Alchemy */
1881 		return;
1882 	}
1883 
1884 	c->options = (MIPS_CPU_TLB	 |
1885 			MIPS_CPU_4KEX	 |
1886 			MIPS_CPU_COUNTER |
1887 			MIPS_CPU_DIVEC	 |
1888 			MIPS_CPU_WATCH	 |
1889 			MIPS_CPU_EJTAG	 |
1890 			MIPS_CPU_LLSC);
1891 
1892 	switch (c->processor_id & PRID_IMP_MASK) {
1893 	case PRID_IMP_NETLOGIC_XLP2XX:
1894 	case PRID_IMP_NETLOGIC_XLP9XX:
1895 	case PRID_IMP_NETLOGIC_XLP5XX:
1896 		c->cputype = CPU_XLP;
1897 		__cpu_name[cpu] = "Broadcom XLPII";
1898 		break;
1899 
1900 	case PRID_IMP_NETLOGIC_XLP8XX:
1901 	case PRID_IMP_NETLOGIC_XLP3XX:
1902 		c->cputype = CPU_XLP;
1903 		__cpu_name[cpu] = "Netlogic XLP";
1904 		break;
1905 
1906 	case PRID_IMP_NETLOGIC_XLR732:
1907 	case PRID_IMP_NETLOGIC_XLR716:
1908 	case PRID_IMP_NETLOGIC_XLR532:
1909 	case PRID_IMP_NETLOGIC_XLR308:
1910 	case PRID_IMP_NETLOGIC_XLR532C:
1911 	case PRID_IMP_NETLOGIC_XLR516C:
1912 	case PRID_IMP_NETLOGIC_XLR508C:
1913 	case PRID_IMP_NETLOGIC_XLR308C:
1914 		c->cputype = CPU_XLR;
1915 		__cpu_name[cpu] = "Netlogic XLR";
1916 		break;
1917 
1918 	case PRID_IMP_NETLOGIC_XLS608:
1919 	case PRID_IMP_NETLOGIC_XLS408:
1920 	case PRID_IMP_NETLOGIC_XLS404:
1921 	case PRID_IMP_NETLOGIC_XLS208:
1922 	case PRID_IMP_NETLOGIC_XLS204:
1923 	case PRID_IMP_NETLOGIC_XLS108:
1924 	case PRID_IMP_NETLOGIC_XLS104:
1925 	case PRID_IMP_NETLOGIC_XLS616B:
1926 	case PRID_IMP_NETLOGIC_XLS608B:
1927 	case PRID_IMP_NETLOGIC_XLS416B:
1928 	case PRID_IMP_NETLOGIC_XLS412B:
1929 	case PRID_IMP_NETLOGIC_XLS408B:
1930 	case PRID_IMP_NETLOGIC_XLS404B:
1931 		c->cputype = CPU_XLR;
1932 		__cpu_name[cpu] = "Netlogic XLS";
1933 		break;
1934 
1935 	default:
1936 		pr_info("Unknown Netlogic chip id [%02x]!\n",
1937 		       c->processor_id);
1938 		c->cputype = CPU_XLR;
1939 		break;
1940 	}
1941 
1942 	if (c->cputype == CPU_XLP) {
1943 		set_isa(c, MIPS_CPU_ISA_M64R2);
1944 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
1945 		/* This will be updated again after all threads are woken up */
1946 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
1947 	} else {
1948 		set_isa(c, MIPS_CPU_ISA_M64R1);
1949 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
1950 	}
1951 	c->kscratch_mask = 0xf;
1952 }
1953 
1954 #ifdef CONFIG_64BIT
1955 /* For use by uaccess.h */
1956 u64 __ua_limit;
1957 EXPORT_SYMBOL(__ua_limit);
1958 #endif
1959 
1960 const char *__cpu_name[NR_CPUS];
1961 const char *__elf_platform;
1962 
1963 void cpu_probe(void)
1964 {
1965 	struct cpuinfo_mips *c = &current_cpu_data;
1966 	unsigned int cpu = smp_processor_id();
1967 
1968 	/*
1969 	 * Set a default elf platform, cpu probe may later
1970 	 * overwrite it with a more precise value
1971 	 */
1972 	set_elf_platform(cpu, "mips");
1973 
1974 	c->processor_id = PRID_IMP_UNKNOWN;
1975 	c->fpu_id	= FPIR_IMP_NONE;
1976 	c->cputype	= CPU_UNKNOWN;
1977 	c->writecombine = _CACHE_UNCACHED;
1978 
1979 	c->fpu_csr31	= FPU_CSR_RN;
1980 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
1981 
1982 	c->processor_id = read_c0_prid();
1983 	switch (c->processor_id & PRID_COMP_MASK) {
1984 	case PRID_COMP_LEGACY:
1985 		cpu_probe_legacy(c, cpu);
1986 		break;
1987 	case PRID_COMP_MIPS:
1988 		cpu_probe_mips(c, cpu);
1989 		break;
1990 	case PRID_COMP_ALCHEMY:
1991 		cpu_probe_alchemy(c, cpu);
1992 		break;
1993 	case PRID_COMP_SIBYTE:
1994 		cpu_probe_sibyte(c, cpu);
1995 		break;
1996 	case PRID_COMP_BROADCOM:
1997 		cpu_probe_broadcom(c, cpu);
1998 		break;
1999 	case PRID_COMP_SANDCRAFT:
2000 		cpu_probe_sandcraft(c, cpu);
2001 		break;
2002 	case PRID_COMP_NXP:
2003 		cpu_probe_nxp(c, cpu);
2004 		break;
2005 	case PRID_COMP_CAVIUM:
2006 		cpu_probe_cavium(c, cpu);
2007 		break;
2008 	case PRID_COMP_LOONGSON:
2009 		cpu_probe_loongson(c, cpu);
2010 		break;
2011 	case PRID_COMP_INGENIC_D0:
2012 	case PRID_COMP_INGENIC_D1:
2013 	case PRID_COMP_INGENIC_E1:
2014 		cpu_probe_ingenic(c, cpu);
2015 		break;
2016 	case PRID_COMP_NETLOGIC:
2017 		cpu_probe_netlogic(c, cpu);
2018 		break;
2019 	}
2020 
2021 	BUG_ON(!__cpu_name[cpu]);
2022 	BUG_ON(c->cputype == CPU_UNKNOWN);
2023 
2024 	/*
2025 	 * Platform code can force the cpu type to optimize code
2026 	 * generation. In that case be sure the cpu type is correctly
2027 	 * manually setup otherwise it could trigger some nasty bugs.
2028 	 */
2029 	BUG_ON(current_cpu_type() != c->cputype);
2030 
2031 	if (cpu_has_rixi) {
2032 		/* Enable the RIXI exceptions */
2033 		set_c0_pagegrain(PG_IEC);
2034 		back_to_back_c0_hazard();
2035 		/* Verify the IEC bit is set */
2036 		if (read_c0_pagegrain() & PG_IEC)
2037 			c->options |= MIPS_CPU_RIXIEX;
2038 	}
2039 
2040 	if (mips_fpu_disabled)
2041 		c->options &= ~MIPS_CPU_FPU;
2042 
2043 	if (mips_dsp_disabled)
2044 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2045 
2046 	if (mips_htw_disabled) {
2047 		c->options &= ~MIPS_CPU_HTW;
2048 		write_c0_pwctl(read_c0_pwctl() &
2049 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2050 	}
2051 
2052 	if (c->options & MIPS_CPU_FPU)
2053 		cpu_set_fpu_opts(c);
2054 	else
2055 		cpu_set_nofpu_opts(c);
2056 
2057 	if (cpu_has_bp_ghist)
2058 		write_c0_r10k_diag(read_c0_r10k_diag() |
2059 				   R10K_DIAG_E_GHIST);
2060 
2061 	if (cpu_has_mips_r2_r6) {
2062 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2063 		/* R2 has Performance Counter Interrupt indicator */
2064 		c->options |= MIPS_CPU_PCI;
2065 	}
2066 	else
2067 		c->srsets = 1;
2068 
2069 	if (cpu_has_mips_r6)
2070 		elf_hwcap |= HWCAP_MIPS_R6;
2071 
2072 	if (cpu_has_msa) {
2073 		c->msa_id = cpu_get_msa_id();
2074 		WARN(c->msa_id & MSA_IR_WRPF,
2075 		     "Vector register partitioning unimplemented!");
2076 		elf_hwcap |= HWCAP_MIPS_MSA;
2077 	}
2078 
2079 	if (cpu_has_vz)
2080 		cpu_probe_vz(c);
2081 
2082 	cpu_probe_vmbits(c);
2083 
2084 #ifdef CONFIG_64BIT
2085 	if (cpu == 0)
2086 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2087 #endif
2088 }
2089 
2090 void cpu_report(void)
2091 {
2092 	struct cpuinfo_mips *c = &current_cpu_data;
2093 
2094 	pr_info("CPU%d revision is: %08x (%s)\n",
2095 		smp_processor_id(), c->processor_id, cpu_name_string());
2096 	if (c->options & MIPS_CPU_FPU)
2097 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2098 	if (cpu_has_msa)
2099 		pr_info("MSA revision is: %08x\n", c->msa_id);
2100 }
2101 
2102 void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
2103 {
2104 	/* Ensure the core number fits in the field */
2105 	WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
2106 			   MIPS_GLOBALNUMBER_CLUSTER_SHF));
2107 
2108 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
2109 	cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
2110 }
2111 
2112 void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
2113 {
2114 	/* Ensure the core number fits in the field */
2115 	WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
2116 
2117 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
2118 	cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
2119 }
2120 
2121 void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
2122 {
2123 	/* Ensure the VP(E) ID fits in the field */
2124 	WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
2125 
2126 	/* Ensure we're not using VP(E)s without support */
2127 	WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
2128 		!IS_ENABLED(CONFIG_CPU_MIPSR6));
2129 
2130 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
2131 	cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
2132 }
2133