xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 82b5d164)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Processor capabilities determination functions.
4  *
5  * Copyright (C) xxxx  the Anonymous
6  * Copyright (C) 1994 - 2006 Ralf Baechle
7  * Copyright (C) 2003, 2004  Maciej W. Rozycki
8  * Copyright (C) 2001, 2004, 2011, 2012	 MIPS Technologies, Inc.
9  */
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/ptrace.h>
13 #include <linux/smp.h>
14 #include <linux/stddef.h>
15 #include <linux/export.h>
16 
17 #include <asm/bugs.h>
18 #include <asm/cpu.h>
19 #include <asm/cpu-features.h>
20 #include <asm/cpu-type.h>
21 #include <asm/fpu.h>
22 #include <asm/mipsregs.h>
23 #include <asm/mipsmtregs.h>
24 #include <asm/msa.h>
25 #include <asm/watch.h>
26 #include <asm/elf.h>
27 #include <asm/pgtable-bits.h>
28 #include <asm/spram.h>
29 #include <linux/uaccess.h>
30 
31 /* Hardware capabilities */
32 unsigned int elf_hwcap __read_mostly;
33 EXPORT_SYMBOL_GPL(elf_hwcap);
34 
35 #ifdef CONFIG_MIPS_FP_SUPPORT
36 
37 /*
38  * Get the FPU Implementation/Revision.
39  */
40 static inline unsigned long cpu_get_fpu_id(void)
41 {
42 	unsigned long tmp, fpu_id;
43 
44 	tmp = read_c0_status();
45 	__enable_fpu(FPU_AS_IS);
46 	fpu_id = read_32bit_cp1_register(CP1_REVISION);
47 	write_c0_status(tmp);
48 	return fpu_id;
49 }
50 
51 /*
52  * Check if the CPU has an external FPU.
53  */
54 static inline int __cpu_has_fpu(void)
55 {
56 	return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
57 }
58 
59 /*
60  * Determine the FCSR mask for FPU hardware.
61  */
62 static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_mips *c)
63 {
64 	unsigned long sr, mask, fcsr, fcsr0, fcsr1;
65 
66 	fcsr = c->fpu_csr31;
67 	mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
68 
69 	sr = read_c0_status();
70 	__enable_fpu(FPU_AS_IS);
71 
72 	fcsr0 = fcsr & mask;
73 	write_32bit_cp1_register(CP1_STATUS, fcsr0);
74 	fcsr0 = read_32bit_cp1_register(CP1_STATUS);
75 
76 	fcsr1 = fcsr | ~mask;
77 	write_32bit_cp1_register(CP1_STATUS, fcsr1);
78 	fcsr1 = read_32bit_cp1_register(CP1_STATUS);
79 
80 	write_32bit_cp1_register(CP1_STATUS, fcsr);
81 
82 	write_c0_status(sr);
83 
84 	c->fpu_msk31 = ~(fcsr0 ^ fcsr1) & ~mask;
85 }
86 
87 /*
88  * Determine the IEEE 754 NaN encodings and ABS.fmt/NEG.fmt execution modes
89  * supported by FPU hardware.
90  */
91 static void cpu_set_fpu_2008(struct cpuinfo_mips *c)
92 {
93 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
94 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
95 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
96 		unsigned long sr, fir, fcsr, fcsr0, fcsr1;
97 
98 		sr = read_c0_status();
99 		__enable_fpu(FPU_AS_IS);
100 
101 		fir = read_32bit_cp1_register(CP1_REVISION);
102 		if (fir & MIPS_FPIR_HAS2008) {
103 			fcsr = read_32bit_cp1_register(CP1_STATUS);
104 
105 			fcsr0 = fcsr & ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
106 			write_32bit_cp1_register(CP1_STATUS, fcsr0);
107 			fcsr0 = read_32bit_cp1_register(CP1_STATUS);
108 
109 			fcsr1 = fcsr | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
110 			write_32bit_cp1_register(CP1_STATUS, fcsr1);
111 			fcsr1 = read_32bit_cp1_register(CP1_STATUS);
112 
113 			write_32bit_cp1_register(CP1_STATUS, fcsr);
114 
115 			if (!(fcsr0 & FPU_CSR_NAN2008))
116 				c->options |= MIPS_CPU_NAN_LEGACY;
117 			if (fcsr1 & FPU_CSR_NAN2008)
118 				c->options |= MIPS_CPU_NAN_2008;
119 
120 			if ((fcsr0 ^ fcsr1) & FPU_CSR_ABS2008)
121 				c->fpu_msk31 &= ~FPU_CSR_ABS2008;
122 			else
123 				c->fpu_csr31 |= fcsr & FPU_CSR_ABS2008;
124 
125 			if ((fcsr0 ^ fcsr1) & FPU_CSR_NAN2008)
126 				c->fpu_msk31 &= ~FPU_CSR_NAN2008;
127 			else
128 				c->fpu_csr31 |= fcsr & FPU_CSR_NAN2008;
129 		} else {
130 			c->options |= MIPS_CPU_NAN_LEGACY;
131 		}
132 
133 		write_c0_status(sr);
134 	} else {
135 		c->options |= MIPS_CPU_NAN_LEGACY;
136 	}
137 }
138 
139 /*
140  * IEEE 754 conformance mode to use.  Affects the NaN encoding and the
141  * ABS.fmt/NEG.fmt execution mode.
142  */
143 static enum { STRICT, LEGACY, STD2008, RELAXED } ieee754 = STRICT;
144 
145 /*
146  * Set the IEEE 754 NaN encodings and the ABS.fmt/NEG.fmt execution modes
147  * to support by the FPU emulator according to the IEEE 754 conformance
148  * mode selected.  Note that "relaxed" straps the emulator so that it
149  * allows 2008-NaN binaries even for legacy processors.
150  */
151 static void cpu_set_nofpu_2008(struct cpuinfo_mips *c)
152 {
153 	c->options &= ~(MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY);
154 	c->fpu_csr31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
155 	c->fpu_msk31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
156 
157 	switch (ieee754) {
158 	case STRICT:
159 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
160 				    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
161 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
162 			c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
163 		} else {
164 			c->options |= MIPS_CPU_NAN_LEGACY;
165 			c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
166 		}
167 		break;
168 	case LEGACY:
169 		c->options |= MIPS_CPU_NAN_LEGACY;
170 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
171 		break;
172 	case STD2008:
173 		c->options |= MIPS_CPU_NAN_2008;
174 		c->fpu_csr31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
175 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
176 		break;
177 	case RELAXED:
178 		c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
179 		break;
180 	}
181 }
182 
183 /*
184  * Override the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode
185  * according to the "ieee754=" parameter.
186  */
187 static void cpu_set_nan_2008(struct cpuinfo_mips *c)
188 {
189 	switch (ieee754) {
190 	case STRICT:
191 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
192 		mips_use_nan_2008 = !!cpu_has_nan_2008;
193 		break;
194 	case LEGACY:
195 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
196 		mips_use_nan_2008 = !cpu_has_nan_legacy;
197 		break;
198 	case STD2008:
199 		mips_use_nan_legacy = !cpu_has_nan_2008;
200 		mips_use_nan_2008 = !!cpu_has_nan_2008;
201 		break;
202 	case RELAXED:
203 		mips_use_nan_legacy = true;
204 		mips_use_nan_2008 = true;
205 		break;
206 	}
207 }
208 
209 /*
210  * IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode override
211  * settings:
212  *
213  * strict:  accept binaries that request a NaN encoding supported by the FPU
214  * legacy:  only accept legacy-NaN binaries
215  * 2008:    only accept 2008-NaN binaries
216  * relaxed: accept any binaries regardless of whether supported by the FPU
217  */
218 static int __init ieee754_setup(char *s)
219 {
220 	if (!s)
221 		return -1;
222 	else if (!strcmp(s, "strict"))
223 		ieee754 = STRICT;
224 	else if (!strcmp(s, "legacy"))
225 		ieee754 = LEGACY;
226 	else if (!strcmp(s, "2008"))
227 		ieee754 = STD2008;
228 	else if (!strcmp(s, "relaxed"))
229 		ieee754 = RELAXED;
230 	else
231 		return -1;
232 
233 	if (!(boot_cpu_data.options & MIPS_CPU_FPU))
234 		cpu_set_nofpu_2008(&boot_cpu_data);
235 	cpu_set_nan_2008(&boot_cpu_data);
236 
237 	return 0;
238 }
239 
240 early_param("ieee754", ieee754_setup);
241 
242 /*
243  * Set the FIR feature flags for the FPU emulator.
244  */
245 static void cpu_set_nofpu_id(struct cpuinfo_mips *c)
246 {
247 	u32 value;
248 
249 	value = 0;
250 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
251 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
252 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
253 		value |= MIPS_FPIR_D | MIPS_FPIR_S;
254 	if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
255 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
256 		value |= MIPS_FPIR_F64 | MIPS_FPIR_L | MIPS_FPIR_W;
257 	if (c->options & MIPS_CPU_NAN_2008)
258 		value |= MIPS_FPIR_HAS2008;
259 	c->fpu_id = value;
260 }
261 
262 /* Determined FPU emulator mask to use for the boot CPU with "nofpu".  */
263 static unsigned int mips_nofpu_msk31;
264 
265 /*
266  * Set options for FPU hardware.
267  */
268 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
269 {
270 	c->fpu_id = cpu_get_fpu_id();
271 	mips_nofpu_msk31 = c->fpu_msk31;
272 
273 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
274 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
275 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
276 		if (c->fpu_id & MIPS_FPIR_3D)
277 			c->ases |= MIPS_ASE_MIPS3D;
278 		if (c->fpu_id & MIPS_FPIR_UFRP)
279 			c->options |= MIPS_CPU_UFR;
280 		if (c->fpu_id & MIPS_FPIR_FREP)
281 			c->options |= MIPS_CPU_FRE;
282 	}
283 
284 	cpu_set_fpu_fcsr_mask(c);
285 	cpu_set_fpu_2008(c);
286 	cpu_set_nan_2008(c);
287 }
288 
289 /*
290  * Set options for the FPU emulator.
291  */
292 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
293 {
294 	c->options &= ~MIPS_CPU_FPU;
295 	c->fpu_msk31 = mips_nofpu_msk31;
296 
297 	cpu_set_nofpu_2008(c);
298 	cpu_set_nan_2008(c);
299 	cpu_set_nofpu_id(c);
300 }
301 
302 static int mips_fpu_disabled;
303 
304 static int __init fpu_disable(char *s)
305 {
306 	cpu_set_nofpu_opts(&boot_cpu_data);
307 	mips_fpu_disabled = 1;
308 
309 	return 1;
310 }
311 
312 __setup("nofpu", fpu_disable);
313 
314 #else /* !CONFIG_MIPS_FP_SUPPORT */
315 
316 #define mips_fpu_disabled 1
317 
318 static inline unsigned long cpu_get_fpu_id(void)
319 {
320 	return FPIR_IMP_NONE;
321 }
322 
323 static inline int __cpu_has_fpu(void)
324 {
325 	return 0;
326 }
327 
328 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
329 {
330 	/* no-op */
331 }
332 
333 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
334 {
335 	/* no-op */
336 }
337 
338 #endif /* CONFIG_MIPS_FP_SUPPORT */
339 
340 static inline unsigned long cpu_get_msa_id(void)
341 {
342 	unsigned long status, msa_id;
343 
344 	status = read_c0_status();
345 	__enable_fpu(FPU_64BIT);
346 	enable_msa();
347 	msa_id = read_msa_ir();
348 	disable_msa();
349 	write_c0_status(status);
350 	return msa_id;
351 }
352 
353 static int mips_dsp_disabled;
354 
355 static int __init dsp_disable(char *s)
356 {
357 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
358 	mips_dsp_disabled = 1;
359 
360 	return 1;
361 }
362 
363 __setup("nodsp", dsp_disable);
364 
365 static int mips_htw_disabled;
366 
367 static int __init htw_disable(char *s)
368 {
369 	mips_htw_disabled = 1;
370 	cpu_data[0].options &= ~MIPS_CPU_HTW;
371 	write_c0_pwctl(read_c0_pwctl() &
372 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
373 
374 	return 1;
375 }
376 
377 __setup("nohtw", htw_disable);
378 
379 static int mips_ftlb_disabled;
380 static int mips_has_ftlb_configured;
381 
382 enum ftlb_flags {
383 	FTLB_EN		= 1 << 0,
384 	FTLB_SET_PROB	= 1 << 1,
385 };
386 
387 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
388 
389 static int __init ftlb_disable(char *s)
390 {
391 	unsigned int config4, mmuextdef;
392 
393 	/*
394 	 * If the core hasn't done any FTLB configuration, there is nothing
395 	 * for us to do here.
396 	 */
397 	if (!mips_has_ftlb_configured)
398 		return 1;
399 
400 	/* Disable it in the boot cpu */
401 	if (set_ftlb_enable(&cpu_data[0], 0)) {
402 		pr_warn("Can't turn FTLB off\n");
403 		return 1;
404 	}
405 
406 	config4 = read_c0_config4();
407 
408 	/* Check that FTLB has been disabled */
409 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
410 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
411 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
412 		/* This should never happen */
413 		pr_warn("FTLB could not be disabled!\n");
414 		return 1;
415 	}
416 
417 	mips_ftlb_disabled = 1;
418 	mips_has_ftlb_configured = 0;
419 
420 	/*
421 	 * noftlb is mainly used for debug purposes so print
422 	 * an informative message instead of using pr_debug()
423 	 */
424 	pr_info("FTLB has been disabled\n");
425 
426 	/*
427 	 * Some of these bits are duplicated in the decode_config4.
428 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
429 	 * once FTLB has been disabled so undo what decode_config4 did.
430 	 */
431 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
432 			       cpu_data[0].tlbsizeftlbsets;
433 	cpu_data[0].tlbsizeftlbsets = 0;
434 	cpu_data[0].tlbsizeftlbways = 0;
435 
436 	return 1;
437 }
438 
439 __setup("noftlb", ftlb_disable);
440 
441 /*
442  * Check if the CPU has per tc perf counters
443  */
444 static inline void cpu_set_mt_per_tc_perf(struct cpuinfo_mips *c)
445 {
446 	if (read_c0_config7() & MTI_CONF7_PTC)
447 		c->options |= MIPS_CPU_MT_PER_TC_PERF_COUNTERS;
448 }
449 
450 static inline void check_errata(void)
451 {
452 	struct cpuinfo_mips *c = &current_cpu_data;
453 
454 	switch (current_cpu_type()) {
455 	case CPU_34K:
456 		/*
457 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
458 		 * This code only handles VPE0, any SMP/RTOS code
459 		 * making use of VPE1 will be responsable for that VPE.
460 		 */
461 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
462 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
463 		break;
464 	default:
465 		break;
466 	}
467 }
468 
469 void __init check_bugs32(void)
470 {
471 	check_errata();
472 }
473 
474 /*
475  * Probe whether cpu has config register by trying to play with
476  * alternate cache bit and see whether it matters.
477  * It's used by cpu_probe to distinguish between R3000A and R3081.
478  */
479 static inline int cpu_has_confreg(void)
480 {
481 #ifdef CONFIG_CPU_R3000
482 	extern unsigned long r3k_cache_size(unsigned long);
483 	unsigned long size1, size2;
484 	unsigned long cfg = read_c0_conf();
485 
486 	size1 = r3k_cache_size(ST0_ISC);
487 	write_c0_conf(cfg ^ R30XX_CONF_AC);
488 	size2 = r3k_cache_size(ST0_ISC);
489 	write_c0_conf(cfg);
490 	return size1 != size2;
491 #else
492 	return 0;
493 #endif
494 }
495 
496 static inline void set_elf_platform(int cpu, const char *plat)
497 {
498 	if (cpu == 0)
499 		__elf_platform = plat;
500 }
501 
502 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
503 {
504 #ifdef __NEED_VMBITS_PROBE
505 	write_c0_entryhi(0x3fffffffffffe000ULL);
506 	back_to_back_c0_hazard();
507 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
508 #endif
509 }
510 
511 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
512 {
513 	switch (isa) {
514 	case MIPS_CPU_ISA_M64R2:
515 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
516 		/* fall through */
517 	case MIPS_CPU_ISA_M64R1:
518 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
519 		/* fall through */
520 	case MIPS_CPU_ISA_V:
521 		c->isa_level |= MIPS_CPU_ISA_V;
522 		/* fall through */
523 	case MIPS_CPU_ISA_IV:
524 		c->isa_level |= MIPS_CPU_ISA_IV;
525 		/* fall through */
526 	case MIPS_CPU_ISA_III:
527 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
528 		break;
529 
530 	/* R6 incompatible with everything else */
531 	case MIPS_CPU_ISA_M64R6:
532 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
533 		/* fall through */
534 	case MIPS_CPU_ISA_M32R6:
535 		c->isa_level |= MIPS_CPU_ISA_M32R6;
536 		/* Break here so we don't add incompatible ISAs */
537 		break;
538 	case MIPS_CPU_ISA_M32R2:
539 		c->isa_level |= MIPS_CPU_ISA_M32R2;
540 		/* fall through */
541 	case MIPS_CPU_ISA_M32R1:
542 		c->isa_level |= MIPS_CPU_ISA_M32R1;
543 		/* fall through */
544 	case MIPS_CPU_ISA_II:
545 		c->isa_level |= MIPS_CPU_ISA_II;
546 		break;
547 	}
548 }
549 
550 static char unknown_isa[] = KERN_ERR \
551 	"Unsupported ISA type, c0.config0: %d.";
552 
553 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
554 {
555 
556 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
557 
558 	/*
559 	 * 0 = All TLBWR instructions go to FTLB
560 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
561 	 * FTLB and 1 goes to the VTLB.
562 	 * 2 = 7:1: As above with 7:1 ratio.
563 	 * 3 = 3:1: As above with 3:1 ratio.
564 	 *
565 	 * Use the linear midpoint as the probability threshold.
566 	 */
567 	if (probability >= 12)
568 		return 1;
569 	else if (probability >= 6)
570 		return 2;
571 	else
572 		/*
573 		 * So FTLB is less than 4 times bigger than VTLB.
574 		 * A 3:1 ratio can still be useful though.
575 		 */
576 		return 3;
577 }
578 
579 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
580 {
581 	unsigned int config;
582 
583 	/* It's implementation dependent how the FTLB can be enabled */
584 	switch (c->cputype) {
585 	case CPU_PROAPTIV:
586 	case CPU_P5600:
587 	case CPU_P6600:
588 		/* proAptiv & related cores use Config6 to enable the FTLB */
589 		config = read_c0_config6();
590 
591 		if (flags & FTLB_EN)
592 			config |= MIPS_CONF6_FTLBEN;
593 		else
594 			config &= ~MIPS_CONF6_FTLBEN;
595 
596 		if (flags & FTLB_SET_PROB) {
597 			config &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
598 			config |= calculate_ftlb_probability(c)
599 				  << MIPS_CONF6_FTLBP_SHIFT;
600 		}
601 
602 		write_c0_config6(config);
603 		back_to_back_c0_hazard();
604 		break;
605 	case CPU_I6400:
606 	case CPU_I6500:
607 		/* There's no way to disable the FTLB */
608 		if (!(flags & FTLB_EN))
609 			return 1;
610 		return 0;
611 	case CPU_LOONGSON3:
612 		/* Flush ITLB, DTLB, VTLB and FTLB */
613 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
614 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
615 		/* Loongson-3 cores use Config6 to enable the FTLB */
616 		config = read_c0_config6();
617 		if (flags & FTLB_EN)
618 			/* Enable FTLB */
619 			write_c0_config6(config & ~MIPS_CONF6_FTLBDIS);
620 		else
621 			/* Disable FTLB */
622 			write_c0_config6(config | MIPS_CONF6_FTLBDIS);
623 		break;
624 	default:
625 		return 1;
626 	}
627 
628 	return 0;
629 }
630 
631 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
632 {
633 	unsigned int config0;
634 	int isa, mt;
635 
636 	config0 = read_c0_config();
637 
638 	/*
639 	 * Look for Standard TLB or Dual VTLB and FTLB
640 	 */
641 	mt = config0 & MIPS_CONF_MT;
642 	if (mt == MIPS_CONF_MT_TLB)
643 		c->options |= MIPS_CPU_TLB;
644 	else if (mt == MIPS_CONF_MT_FTLB)
645 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
646 
647 	isa = (config0 & MIPS_CONF_AT) >> 13;
648 	switch (isa) {
649 	case 0:
650 		switch ((config0 & MIPS_CONF_AR) >> 10) {
651 		case 0:
652 			set_isa(c, MIPS_CPU_ISA_M32R1);
653 			break;
654 		case 1:
655 			set_isa(c, MIPS_CPU_ISA_M32R2);
656 			break;
657 		case 2:
658 			set_isa(c, MIPS_CPU_ISA_M32R6);
659 			break;
660 		default:
661 			goto unknown;
662 		}
663 		break;
664 	case 2:
665 		switch ((config0 & MIPS_CONF_AR) >> 10) {
666 		case 0:
667 			set_isa(c, MIPS_CPU_ISA_M64R1);
668 			break;
669 		case 1:
670 			set_isa(c, MIPS_CPU_ISA_M64R2);
671 			break;
672 		case 2:
673 			set_isa(c, MIPS_CPU_ISA_M64R6);
674 			break;
675 		default:
676 			goto unknown;
677 		}
678 		break;
679 	default:
680 		goto unknown;
681 	}
682 
683 	return config0 & MIPS_CONF_M;
684 
685 unknown:
686 	panic(unknown_isa, config0);
687 }
688 
689 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
690 {
691 	unsigned int config1;
692 
693 	config1 = read_c0_config1();
694 
695 	if (config1 & MIPS_CONF1_MD)
696 		c->ases |= MIPS_ASE_MDMX;
697 	if (config1 & MIPS_CONF1_PC)
698 		c->options |= MIPS_CPU_PERF;
699 	if (config1 & MIPS_CONF1_WR)
700 		c->options |= MIPS_CPU_WATCH;
701 	if (config1 & MIPS_CONF1_CA)
702 		c->ases |= MIPS_ASE_MIPS16;
703 	if (config1 & MIPS_CONF1_EP)
704 		c->options |= MIPS_CPU_EJTAG;
705 	if (config1 & MIPS_CONF1_FP) {
706 		c->options |= MIPS_CPU_FPU;
707 		c->options |= MIPS_CPU_32FPR;
708 	}
709 	if (cpu_has_tlb) {
710 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
711 		c->tlbsizevtlb = c->tlbsize;
712 		c->tlbsizeftlbsets = 0;
713 	}
714 
715 	return config1 & MIPS_CONF_M;
716 }
717 
718 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
719 {
720 	unsigned int config2;
721 
722 	config2 = read_c0_config2();
723 
724 	if (config2 & MIPS_CONF2_SL)
725 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
726 
727 	return config2 & MIPS_CONF_M;
728 }
729 
730 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
731 {
732 	unsigned int config3;
733 
734 	config3 = read_c0_config3();
735 
736 	if (config3 & MIPS_CONF3_SM) {
737 		c->ases |= MIPS_ASE_SMARTMIPS;
738 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
739 	}
740 	if (config3 & MIPS_CONF3_RXI)
741 		c->options |= MIPS_CPU_RIXI;
742 	if (config3 & MIPS_CONF3_CTXTC)
743 		c->options |= MIPS_CPU_CTXTC;
744 	if (config3 & MIPS_CONF3_DSP)
745 		c->ases |= MIPS_ASE_DSP;
746 	if (config3 & MIPS_CONF3_DSP2P) {
747 		c->ases |= MIPS_ASE_DSP2P;
748 		if (cpu_has_mips_r6)
749 			c->ases |= MIPS_ASE_DSP3;
750 	}
751 	if (config3 & MIPS_CONF3_VINT)
752 		c->options |= MIPS_CPU_VINT;
753 	if (config3 & MIPS_CONF3_VEIC)
754 		c->options |= MIPS_CPU_VEIC;
755 	if (config3 & MIPS_CONF3_LPA)
756 		c->options |= MIPS_CPU_LPA;
757 	if (config3 & MIPS_CONF3_MT)
758 		c->ases |= MIPS_ASE_MIPSMT;
759 	if (config3 & MIPS_CONF3_ULRI)
760 		c->options |= MIPS_CPU_ULRI;
761 	if (config3 & MIPS_CONF3_ISA)
762 		c->options |= MIPS_CPU_MICROMIPS;
763 	if (config3 & MIPS_CONF3_VZ)
764 		c->ases |= MIPS_ASE_VZ;
765 	if (config3 & MIPS_CONF3_SC)
766 		c->options |= MIPS_CPU_SEGMENTS;
767 	if (config3 & MIPS_CONF3_BI)
768 		c->options |= MIPS_CPU_BADINSTR;
769 	if (config3 & MIPS_CONF3_BP)
770 		c->options |= MIPS_CPU_BADINSTRP;
771 	if (config3 & MIPS_CONF3_MSA)
772 		c->ases |= MIPS_ASE_MSA;
773 	if (config3 & MIPS_CONF3_PW) {
774 		c->htw_seq = 0;
775 		c->options |= MIPS_CPU_HTW;
776 	}
777 	if (config3 & MIPS_CONF3_CDMM)
778 		c->options |= MIPS_CPU_CDMM;
779 	if (config3 & MIPS_CONF3_SP)
780 		c->options |= MIPS_CPU_SP;
781 
782 	return config3 & MIPS_CONF_M;
783 }
784 
785 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
786 {
787 	unsigned int config4;
788 	unsigned int newcf4;
789 	unsigned int mmuextdef;
790 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
791 	unsigned long asid_mask;
792 
793 	config4 = read_c0_config4();
794 
795 	if (cpu_has_tlb) {
796 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
797 			c->options |= MIPS_CPU_TLBINV;
798 
799 		/*
800 		 * R6 has dropped the MMUExtDef field from config4.
801 		 * On R6 the fields always describe the FTLB, and only if it is
802 		 * present according to Config.MT.
803 		 */
804 		if (!cpu_has_mips_r6)
805 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
806 		else if (cpu_has_ftlb)
807 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
808 		else
809 			mmuextdef = 0;
810 
811 		switch (mmuextdef) {
812 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
813 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
814 			c->tlbsizevtlb = c->tlbsize;
815 			break;
816 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
817 			c->tlbsizevtlb +=
818 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
819 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
820 			c->tlbsize = c->tlbsizevtlb;
821 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
822 			/* fall through */
823 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
824 			if (mips_ftlb_disabled)
825 				break;
826 			newcf4 = (config4 & ~ftlb_page) |
827 				(page_size_ftlb(mmuextdef) <<
828 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
829 			write_c0_config4(newcf4);
830 			back_to_back_c0_hazard();
831 			config4 = read_c0_config4();
832 			if (config4 != newcf4) {
833 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
834 				       PAGE_SIZE, config4);
835 				/* Switch FTLB off */
836 				set_ftlb_enable(c, 0);
837 				mips_ftlb_disabled = 1;
838 				break;
839 			}
840 			c->tlbsizeftlbsets = 1 <<
841 				((config4 & MIPS_CONF4_FTLBSETS) >>
842 				 MIPS_CONF4_FTLBSETS_SHIFT);
843 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
844 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
845 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
846 			mips_has_ftlb_configured = 1;
847 			break;
848 		}
849 	}
850 
851 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
852 				>> MIPS_CONF4_KSCREXIST_SHIFT;
853 
854 	asid_mask = MIPS_ENTRYHI_ASID;
855 	if (config4 & MIPS_CONF4_AE)
856 		asid_mask |= MIPS_ENTRYHI_ASIDX;
857 	set_cpu_asid_mask(c, asid_mask);
858 
859 	/*
860 	 * Warn if the computed ASID mask doesn't match the mask the kernel
861 	 * is built for. This may indicate either a serious problem or an
862 	 * easy optimisation opportunity, but either way should be addressed.
863 	 */
864 	WARN_ON(asid_mask != cpu_asid_mask(c));
865 
866 	return config4 & MIPS_CONF_M;
867 }
868 
869 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
870 {
871 	unsigned int config5, max_mmid_width;
872 	unsigned long asid_mask;
873 
874 	config5 = read_c0_config5();
875 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
876 
877 	if (cpu_has_mips_r6) {
878 		if (!__builtin_constant_p(cpu_has_mmid) || cpu_has_mmid)
879 			config5 |= MIPS_CONF5_MI;
880 		else
881 			config5 &= ~MIPS_CONF5_MI;
882 	}
883 
884 	write_c0_config5(config5);
885 
886 	if (config5 & MIPS_CONF5_EVA)
887 		c->options |= MIPS_CPU_EVA;
888 	if (config5 & MIPS_CONF5_MRP)
889 		c->options |= MIPS_CPU_MAAR;
890 	if (config5 & MIPS_CONF5_LLB)
891 		c->options |= MIPS_CPU_RW_LLB;
892 	if (config5 & MIPS_CONF5_MVH)
893 		c->options |= MIPS_CPU_MVH;
894 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
895 		c->options |= MIPS_CPU_VP;
896 	if (config5 & MIPS_CONF5_CA2)
897 		c->ases |= MIPS_ASE_MIPS16E2;
898 
899 	if (config5 & MIPS_CONF5_CRCP)
900 		elf_hwcap |= HWCAP_MIPS_CRC32;
901 
902 	if (cpu_has_mips_r6) {
903 		/* Ensure the write to config5 above takes effect */
904 		back_to_back_c0_hazard();
905 
906 		/* Check whether we successfully enabled MMID support */
907 		config5 = read_c0_config5();
908 		if (config5 & MIPS_CONF5_MI)
909 			c->options |= MIPS_CPU_MMID;
910 
911 		/*
912 		 * Warn if we've hardcoded cpu_has_mmid to a value unsuitable
913 		 * for the CPU we're running on, or if CPUs in an SMP system
914 		 * have inconsistent MMID support.
915 		 */
916 		WARN_ON(!!cpu_has_mmid != !!(config5 & MIPS_CONF5_MI));
917 
918 		if (cpu_has_mmid) {
919 			write_c0_memorymapid(~0ul);
920 			back_to_back_c0_hazard();
921 			asid_mask = read_c0_memorymapid();
922 
923 			/*
924 			 * We maintain a bitmap to track MMID allocation, and
925 			 * need a sensible upper bound on the size of that
926 			 * bitmap. The initial CPU with MMID support (I6500)
927 			 * supports 16 bit MMIDs, which gives us an 8KiB
928 			 * bitmap. The architecture recommends that hardware
929 			 * support 32 bit MMIDs, which would give us a 512MiB
930 			 * bitmap - that's too big in most cases.
931 			 *
932 			 * Cap MMID width at 16 bits for now & we can revisit
933 			 * this if & when hardware supports anything wider.
934 			 */
935 			max_mmid_width = 16;
936 			if (asid_mask > GENMASK(max_mmid_width - 1, 0)) {
937 				pr_info("Capping MMID width at %d bits",
938 					max_mmid_width);
939 				asid_mask = GENMASK(max_mmid_width - 1, 0);
940 			}
941 
942 			set_cpu_asid_mask(c, asid_mask);
943 		}
944 	}
945 
946 	return config5 & MIPS_CONF_M;
947 }
948 
949 static void decode_configs(struct cpuinfo_mips *c)
950 {
951 	int ok;
952 
953 	/* MIPS32 or MIPS64 compliant CPU.  */
954 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
955 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
956 
957 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
958 
959 	/* Enable FTLB if present and not disabled */
960 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
961 
962 	ok = decode_config0(c);			/* Read Config registers.  */
963 	BUG_ON(!ok);				/* Arch spec violation!	 */
964 	if (ok)
965 		ok = decode_config1(c);
966 	if (ok)
967 		ok = decode_config2(c);
968 	if (ok)
969 		ok = decode_config3(c);
970 	if (ok)
971 		ok = decode_config4(c);
972 	if (ok)
973 		ok = decode_config5(c);
974 
975 	/* Probe the EBase.WG bit */
976 	if (cpu_has_mips_r2_r6) {
977 		u64 ebase;
978 		unsigned int status;
979 
980 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
981 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
982 					 : (s32)read_c0_ebase();
983 		if (ebase & MIPS_EBASE_WG) {
984 			/* WG bit already set, we can avoid the clumsy probe */
985 			c->options |= MIPS_CPU_EBASE_WG;
986 		} else {
987 			/* Its UNDEFINED to change EBase while BEV=0 */
988 			status = read_c0_status();
989 			write_c0_status(status | ST0_BEV);
990 			irq_enable_hazard();
991 			/*
992 			 * On pre-r6 cores, this may well clobber the upper bits
993 			 * of EBase. This is hard to avoid without potentially
994 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
995 			 */
996 			if (cpu_has_mips64r6)
997 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
998 			else
999 				write_c0_ebase(ebase | MIPS_EBASE_WG);
1000 			back_to_back_c0_hazard();
1001 			/* Restore BEV */
1002 			write_c0_status(status);
1003 			if (read_c0_ebase() & MIPS_EBASE_WG) {
1004 				c->options |= MIPS_CPU_EBASE_WG;
1005 				write_c0_ebase(ebase);
1006 			}
1007 		}
1008 	}
1009 
1010 	/* configure the FTLB write probability */
1011 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
1012 
1013 	mips_probe_watch_registers(c);
1014 
1015 #ifndef CONFIG_MIPS_CPS
1016 	if (cpu_has_mips_r2_r6) {
1017 		unsigned int core;
1018 
1019 		core = get_ebase_cpunum();
1020 		if (cpu_has_mipsmt)
1021 			core >>= fls(core_nvpes()) - 1;
1022 		cpu_set_core(c, core);
1023 	}
1024 #endif
1025 }
1026 
1027 /*
1028  * Probe for certain guest capabilities by writing config bits and reading back.
1029  * Finally write back the original value.
1030  */
1031 #define probe_gc0_config(name, maxconf, bits)				\
1032 do {									\
1033 	unsigned int tmp;						\
1034 	tmp = read_gc0_##name();					\
1035 	write_gc0_##name(tmp | (bits));					\
1036 	back_to_back_c0_hazard();					\
1037 	maxconf = read_gc0_##name();					\
1038 	write_gc0_##name(tmp);						\
1039 } while (0)
1040 
1041 /*
1042  * Probe for dynamic guest capabilities by changing certain config bits and
1043  * reading back to see if they change. Finally write back the original value.
1044  */
1045 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
1046 do {									\
1047 	maxconf = read_gc0_##name();					\
1048 	write_gc0_##name(maxconf ^ (bits));				\
1049 	back_to_back_c0_hazard();					\
1050 	dynconf = maxconf ^ read_gc0_##name();				\
1051 	write_gc0_##name(maxconf);					\
1052 	maxconf |= dynconf;						\
1053 } while (0)
1054 
1055 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
1056 {
1057 	unsigned int config0;
1058 
1059 	probe_gc0_config(config, config0, MIPS_CONF_M);
1060 
1061 	if (config0 & MIPS_CONF_M)
1062 		c->guest.conf |= BIT(1);
1063 	return config0 & MIPS_CONF_M;
1064 }
1065 
1066 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
1067 {
1068 	unsigned int config1, config1_dyn;
1069 
1070 	probe_gc0_config_dyn(config1, config1, config1_dyn,
1071 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
1072 			     MIPS_CONF1_FP);
1073 
1074 	if (config1 & MIPS_CONF1_FP)
1075 		c->guest.options |= MIPS_CPU_FPU;
1076 	if (config1_dyn & MIPS_CONF1_FP)
1077 		c->guest.options_dyn |= MIPS_CPU_FPU;
1078 
1079 	if (config1 & MIPS_CONF1_WR)
1080 		c->guest.options |= MIPS_CPU_WATCH;
1081 	if (config1_dyn & MIPS_CONF1_WR)
1082 		c->guest.options_dyn |= MIPS_CPU_WATCH;
1083 
1084 	if (config1 & MIPS_CONF1_PC)
1085 		c->guest.options |= MIPS_CPU_PERF;
1086 	if (config1_dyn & MIPS_CONF1_PC)
1087 		c->guest.options_dyn |= MIPS_CPU_PERF;
1088 
1089 	if (config1 & MIPS_CONF_M)
1090 		c->guest.conf |= BIT(2);
1091 	return config1 & MIPS_CONF_M;
1092 }
1093 
1094 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
1095 {
1096 	unsigned int config2;
1097 
1098 	probe_gc0_config(config2, config2, MIPS_CONF_M);
1099 
1100 	if (config2 & MIPS_CONF_M)
1101 		c->guest.conf |= BIT(3);
1102 	return config2 & MIPS_CONF_M;
1103 }
1104 
1105 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
1106 {
1107 	unsigned int config3, config3_dyn;
1108 
1109 	probe_gc0_config_dyn(config3, config3, config3_dyn,
1110 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
1111 			     MIPS_CONF3_CTXTC);
1112 
1113 	if (config3 & MIPS_CONF3_CTXTC)
1114 		c->guest.options |= MIPS_CPU_CTXTC;
1115 	if (config3_dyn & MIPS_CONF3_CTXTC)
1116 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
1117 
1118 	if (config3 & MIPS_CONF3_PW)
1119 		c->guest.options |= MIPS_CPU_HTW;
1120 
1121 	if (config3 & MIPS_CONF3_ULRI)
1122 		c->guest.options |= MIPS_CPU_ULRI;
1123 
1124 	if (config3 & MIPS_CONF3_SC)
1125 		c->guest.options |= MIPS_CPU_SEGMENTS;
1126 
1127 	if (config3 & MIPS_CONF3_BI)
1128 		c->guest.options |= MIPS_CPU_BADINSTR;
1129 	if (config3 & MIPS_CONF3_BP)
1130 		c->guest.options |= MIPS_CPU_BADINSTRP;
1131 
1132 	if (config3 & MIPS_CONF3_MSA)
1133 		c->guest.ases |= MIPS_ASE_MSA;
1134 	if (config3_dyn & MIPS_CONF3_MSA)
1135 		c->guest.ases_dyn |= MIPS_ASE_MSA;
1136 
1137 	if (config3 & MIPS_CONF_M)
1138 		c->guest.conf |= BIT(4);
1139 	return config3 & MIPS_CONF_M;
1140 }
1141 
1142 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
1143 {
1144 	unsigned int config4;
1145 
1146 	probe_gc0_config(config4, config4,
1147 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
1148 
1149 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
1150 				>> MIPS_CONF4_KSCREXIST_SHIFT;
1151 
1152 	if (config4 & MIPS_CONF_M)
1153 		c->guest.conf |= BIT(5);
1154 	return config4 & MIPS_CONF_M;
1155 }
1156 
1157 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
1158 {
1159 	unsigned int config5, config5_dyn;
1160 
1161 	probe_gc0_config_dyn(config5, config5, config5_dyn,
1162 			 MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
1163 
1164 	if (config5 & MIPS_CONF5_MRP)
1165 		c->guest.options |= MIPS_CPU_MAAR;
1166 	if (config5_dyn & MIPS_CONF5_MRP)
1167 		c->guest.options_dyn |= MIPS_CPU_MAAR;
1168 
1169 	if (config5 & MIPS_CONF5_LLB)
1170 		c->guest.options |= MIPS_CPU_RW_LLB;
1171 
1172 	if (config5 & MIPS_CONF5_MVH)
1173 		c->guest.options |= MIPS_CPU_MVH;
1174 
1175 	if (config5 & MIPS_CONF_M)
1176 		c->guest.conf |= BIT(6);
1177 	return config5 & MIPS_CONF_M;
1178 }
1179 
1180 static inline void decode_guest_configs(struct cpuinfo_mips *c)
1181 {
1182 	unsigned int ok;
1183 
1184 	ok = decode_guest_config0(c);
1185 	if (ok)
1186 		ok = decode_guest_config1(c);
1187 	if (ok)
1188 		ok = decode_guest_config2(c);
1189 	if (ok)
1190 		ok = decode_guest_config3(c);
1191 	if (ok)
1192 		ok = decode_guest_config4(c);
1193 	if (ok)
1194 		decode_guest_config5(c);
1195 }
1196 
1197 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
1198 {
1199 	unsigned int guestctl0, temp;
1200 
1201 	guestctl0 = read_c0_guestctl0();
1202 
1203 	if (guestctl0 & MIPS_GCTL0_G0E)
1204 		c->options |= MIPS_CPU_GUESTCTL0EXT;
1205 	if (guestctl0 & MIPS_GCTL0_G1)
1206 		c->options |= MIPS_CPU_GUESTCTL1;
1207 	if (guestctl0 & MIPS_GCTL0_G2)
1208 		c->options |= MIPS_CPU_GUESTCTL2;
1209 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
1210 		c->options |= MIPS_CPU_GUESTID;
1211 
1212 		/*
1213 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
1214 		 * first, otherwise all data accesses will be fully virtualised
1215 		 * as if they were performed by guest mode.
1216 		 */
1217 		write_c0_guestctl1(0);
1218 		tlbw_use_hazard();
1219 
1220 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
1221 		back_to_back_c0_hazard();
1222 		temp = read_c0_guestctl0();
1223 
1224 		if (temp & MIPS_GCTL0_DRG) {
1225 			write_c0_guestctl0(guestctl0);
1226 			c->options |= MIPS_CPU_DRG;
1227 		}
1228 	}
1229 }
1230 
1231 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1232 {
1233 	if (cpu_has_guestid) {
1234 		/* determine the number of bits of GuestID available */
1235 		write_c0_guestctl1(MIPS_GCTL1_ID);
1236 		back_to_back_c0_hazard();
1237 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1238 						>> MIPS_GCTL1_ID_SHIFT;
1239 		write_c0_guestctl1(0);
1240 	}
1241 }
1242 
1243 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1244 {
1245 	/* determine the number of bits of GTOffset available */
1246 	write_c0_gtoffset(0xffffffff);
1247 	back_to_back_c0_hazard();
1248 	c->gtoffset_mask = read_c0_gtoffset();
1249 	write_c0_gtoffset(0);
1250 }
1251 
1252 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1253 {
1254 	cpu_probe_guestctl0(c);
1255 	if (cpu_has_guestctl1)
1256 		cpu_probe_guestctl1(c);
1257 
1258 	cpu_probe_gtoffset(c);
1259 
1260 	decode_guest_configs(c);
1261 }
1262 
1263 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1264 		| MIPS_CPU_COUNTER)
1265 
1266 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1267 {
1268 	switch (c->processor_id & PRID_IMP_MASK) {
1269 	case PRID_IMP_R2000:
1270 		c->cputype = CPU_R2000;
1271 		__cpu_name[cpu] = "R2000";
1272 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1273 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1274 			     MIPS_CPU_NOFPUEX;
1275 		if (__cpu_has_fpu())
1276 			c->options |= MIPS_CPU_FPU;
1277 		c->tlbsize = 64;
1278 		break;
1279 	case PRID_IMP_R3000:
1280 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1281 			if (cpu_has_confreg()) {
1282 				c->cputype = CPU_R3081E;
1283 				__cpu_name[cpu] = "R3081";
1284 			} else {
1285 				c->cputype = CPU_R3000A;
1286 				__cpu_name[cpu] = "R3000A";
1287 			}
1288 		} else {
1289 			c->cputype = CPU_R3000;
1290 			__cpu_name[cpu] = "R3000";
1291 		}
1292 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1293 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1294 			     MIPS_CPU_NOFPUEX;
1295 		if (__cpu_has_fpu())
1296 			c->options |= MIPS_CPU_FPU;
1297 		c->tlbsize = 64;
1298 		break;
1299 	case PRID_IMP_R4000:
1300 		if (read_c0_config() & CONF_SC) {
1301 			if ((c->processor_id & PRID_REV_MASK) >=
1302 			    PRID_REV_R4400) {
1303 				c->cputype = CPU_R4400PC;
1304 				__cpu_name[cpu] = "R4400PC";
1305 			} else {
1306 				c->cputype = CPU_R4000PC;
1307 				__cpu_name[cpu] = "R4000PC";
1308 			}
1309 		} else {
1310 			int cca = read_c0_config() & CONF_CM_CMASK;
1311 			int mc;
1312 
1313 			/*
1314 			 * SC and MC versions can't be reliably told apart,
1315 			 * but only the latter support coherent caching
1316 			 * modes so assume the firmware has set the KSEG0
1317 			 * coherency attribute reasonably (if uncached, we
1318 			 * assume SC).
1319 			 */
1320 			switch (cca) {
1321 			case CONF_CM_CACHABLE_CE:
1322 			case CONF_CM_CACHABLE_COW:
1323 			case CONF_CM_CACHABLE_CUW:
1324 				mc = 1;
1325 				break;
1326 			default:
1327 				mc = 0;
1328 				break;
1329 			}
1330 			if ((c->processor_id & PRID_REV_MASK) >=
1331 			    PRID_REV_R4400) {
1332 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1333 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1334 			} else {
1335 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1336 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1337 			}
1338 		}
1339 
1340 		set_isa(c, MIPS_CPU_ISA_III);
1341 		c->fpu_msk31 |= FPU_CSR_CONDX;
1342 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1343 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1344 			     MIPS_CPU_LLSC;
1345 		c->tlbsize = 48;
1346 		break;
1347 	case PRID_IMP_VR41XX:
1348 		set_isa(c, MIPS_CPU_ISA_III);
1349 		c->fpu_msk31 |= FPU_CSR_CONDX;
1350 		c->options = R4K_OPTS;
1351 		c->tlbsize = 32;
1352 		switch (c->processor_id & 0xf0) {
1353 		case PRID_REV_VR4111:
1354 			c->cputype = CPU_VR4111;
1355 			__cpu_name[cpu] = "NEC VR4111";
1356 			break;
1357 		case PRID_REV_VR4121:
1358 			c->cputype = CPU_VR4121;
1359 			__cpu_name[cpu] = "NEC VR4121";
1360 			break;
1361 		case PRID_REV_VR4122:
1362 			if ((c->processor_id & 0xf) < 0x3) {
1363 				c->cputype = CPU_VR4122;
1364 				__cpu_name[cpu] = "NEC VR4122";
1365 			} else {
1366 				c->cputype = CPU_VR4181A;
1367 				__cpu_name[cpu] = "NEC VR4181A";
1368 			}
1369 			break;
1370 		case PRID_REV_VR4130:
1371 			if ((c->processor_id & 0xf) < 0x4) {
1372 				c->cputype = CPU_VR4131;
1373 				__cpu_name[cpu] = "NEC VR4131";
1374 			} else {
1375 				c->cputype = CPU_VR4133;
1376 				c->options |= MIPS_CPU_LLSC;
1377 				__cpu_name[cpu] = "NEC VR4133";
1378 			}
1379 			break;
1380 		default:
1381 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1382 			c->cputype = CPU_VR41XX;
1383 			__cpu_name[cpu] = "NEC Vr41xx";
1384 			break;
1385 		}
1386 		break;
1387 	case PRID_IMP_R4600:
1388 		c->cputype = CPU_R4600;
1389 		__cpu_name[cpu] = "R4600";
1390 		set_isa(c, MIPS_CPU_ISA_III);
1391 		c->fpu_msk31 |= FPU_CSR_CONDX;
1392 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1393 			     MIPS_CPU_LLSC;
1394 		c->tlbsize = 48;
1395 		break;
1396 	#if 0
1397 	case PRID_IMP_R4650:
1398 		/*
1399 		 * This processor doesn't have an MMU, so it's not
1400 		 * "real easy" to run Linux on it. It is left purely
1401 		 * for documentation.  Commented out because it shares
1402 		 * it's c0_prid id number with the TX3900.
1403 		 */
1404 		c->cputype = CPU_R4650;
1405 		__cpu_name[cpu] = "R4650";
1406 		set_isa(c, MIPS_CPU_ISA_III);
1407 		c->fpu_msk31 |= FPU_CSR_CONDX;
1408 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1409 		c->tlbsize = 48;
1410 		break;
1411 	#endif
1412 	case PRID_IMP_TX39:
1413 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1414 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1415 
1416 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1417 			c->cputype = CPU_TX3927;
1418 			__cpu_name[cpu] = "TX3927";
1419 			c->tlbsize = 64;
1420 		} else {
1421 			switch (c->processor_id & PRID_REV_MASK) {
1422 			case PRID_REV_TX3912:
1423 				c->cputype = CPU_TX3912;
1424 				__cpu_name[cpu] = "TX3912";
1425 				c->tlbsize = 32;
1426 				break;
1427 			case PRID_REV_TX3922:
1428 				c->cputype = CPU_TX3922;
1429 				__cpu_name[cpu] = "TX3922";
1430 				c->tlbsize = 64;
1431 				break;
1432 			}
1433 		}
1434 		break;
1435 	case PRID_IMP_R4700:
1436 		c->cputype = CPU_R4700;
1437 		__cpu_name[cpu] = "R4700";
1438 		set_isa(c, MIPS_CPU_ISA_III);
1439 		c->fpu_msk31 |= FPU_CSR_CONDX;
1440 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1441 			     MIPS_CPU_LLSC;
1442 		c->tlbsize = 48;
1443 		break;
1444 	case PRID_IMP_TX49:
1445 		c->cputype = CPU_TX49XX;
1446 		__cpu_name[cpu] = "R49XX";
1447 		set_isa(c, MIPS_CPU_ISA_III);
1448 		c->fpu_msk31 |= FPU_CSR_CONDX;
1449 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1450 		if (!(c->processor_id & 0x08))
1451 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1452 		c->tlbsize = 48;
1453 		break;
1454 	case PRID_IMP_R5000:
1455 		c->cputype = CPU_R5000;
1456 		__cpu_name[cpu] = "R5000";
1457 		set_isa(c, MIPS_CPU_ISA_IV);
1458 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1459 			     MIPS_CPU_LLSC;
1460 		c->tlbsize = 48;
1461 		break;
1462 	case PRID_IMP_R5500:
1463 		c->cputype = CPU_R5500;
1464 		__cpu_name[cpu] = "R5500";
1465 		set_isa(c, MIPS_CPU_ISA_IV);
1466 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1467 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1468 		c->tlbsize = 48;
1469 		break;
1470 	case PRID_IMP_NEVADA:
1471 		c->cputype = CPU_NEVADA;
1472 		__cpu_name[cpu] = "Nevada";
1473 		set_isa(c, MIPS_CPU_ISA_IV);
1474 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1475 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1476 		c->tlbsize = 48;
1477 		break;
1478 	case PRID_IMP_RM7000:
1479 		c->cputype = CPU_RM7000;
1480 		__cpu_name[cpu] = "RM7000";
1481 		set_isa(c, MIPS_CPU_ISA_IV);
1482 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1483 			     MIPS_CPU_LLSC;
1484 		/*
1485 		 * Undocumented RM7000:	 Bit 29 in the info register of
1486 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1487 		 * entries.
1488 		 *
1489 		 * 29	   1 =>	   64 entry JTLB
1490 		 *	   0 =>	   48 entry JTLB
1491 		 */
1492 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1493 		break;
1494 	case PRID_IMP_R10000:
1495 		c->cputype = CPU_R10000;
1496 		__cpu_name[cpu] = "R10000";
1497 		set_isa(c, MIPS_CPU_ISA_IV);
1498 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1499 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1500 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1501 			     MIPS_CPU_LLSC;
1502 		c->tlbsize = 64;
1503 		break;
1504 	case PRID_IMP_R12000:
1505 		c->cputype = CPU_R12000;
1506 		__cpu_name[cpu] = "R12000";
1507 		set_isa(c, MIPS_CPU_ISA_IV);
1508 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1509 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1510 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1511 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1512 		c->tlbsize = 64;
1513 		break;
1514 	case PRID_IMP_R14000:
1515 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1516 			c->cputype = CPU_R16000;
1517 			__cpu_name[cpu] = "R16000";
1518 		} else {
1519 			c->cputype = CPU_R14000;
1520 			__cpu_name[cpu] = "R14000";
1521 		}
1522 		set_isa(c, MIPS_CPU_ISA_IV);
1523 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1524 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1525 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1526 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1527 		c->tlbsize = 64;
1528 		break;
1529 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1530 		switch (c->processor_id & PRID_REV_MASK) {
1531 		case PRID_REV_LOONGSON2E:
1532 			c->cputype = CPU_LOONGSON2;
1533 			__cpu_name[cpu] = "ICT Loongson-2";
1534 			set_elf_platform(cpu, "loongson2e");
1535 			set_isa(c, MIPS_CPU_ISA_III);
1536 			c->fpu_msk31 |= FPU_CSR_CONDX;
1537 			break;
1538 		case PRID_REV_LOONGSON2F:
1539 			c->cputype = CPU_LOONGSON2;
1540 			__cpu_name[cpu] = "ICT Loongson-2";
1541 			set_elf_platform(cpu, "loongson2f");
1542 			set_isa(c, MIPS_CPU_ISA_III);
1543 			c->fpu_msk31 |= FPU_CSR_CONDX;
1544 			break;
1545 		case PRID_REV_LOONGSON3A_R1:
1546 			c->cputype = CPU_LOONGSON3;
1547 			__cpu_name[cpu] = "ICT Loongson-3";
1548 			set_elf_platform(cpu, "loongson3a");
1549 			set_isa(c, MIPS_CPU_ISA_M64R1);
1550 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1551 				MIPS_ASE_LOONGSON_EXT);
1552 			break;
1553 		case PRID_REV_LOONGSON3B_R1:
1554 		case PRID_REV_LOONGSON3B_R2:
1555 			c->cputype = CPU_LOONGSON3;
1556 			__cpu_name[cpu] = "ICT Loongson-3";
1557 			set_elf_platform(cpu, "loongson3b");
1558 			set_isa(c, MIPS_CPU_ISA_M64R1);
1559 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1560 				MIPS_ASE_LOONGSON_EXT);
1561 			break;
1562 		}
1563 
1564 		c->options = R4K_OPTS |
1565 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1566 			     MIPS_CPU_32FPR;
1567 		c->tlbsize = 64;
1568 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1569 		break;
1570 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1571 		decode_configs(c);
1572 
1573 		c->cputype = CPU_LOONGSON1;
1574 
1575 		switch (c->processor_id & PRID_REV_MASK) {
1576 		case PRID_REV_LOONGSON1B:
1577 			__cpu_name[cpu] = "Loongson 1B";
1578 			break;
1579 		}
1580 
1581 		break;
1582 	}
1583 }
1584 
1585 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1586 {
1587 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1588 	switch (c->processor_id & PRID_IMP_MASK) {
1589 	case PRID_IMP_QEMU_GENERIC:
1590 		c->writecombine = _CACHE_UNCACHED;
1591 		c->cputype = CPU_QEMU_GENERIC;
1592 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1593 		break;
1594 	case PRID_IMP_4KC:
1595 		c->cputype = CPU_4KC;
1596 		c->writecombine = _CACHE_UNCACHED;
1597 		__cpu_name[cpu] = "MIPS 4Kc";
1598 		break;
1599 	case PRID_IMP_4KEC:
1600 	case PRID_IMP_4KECR2:
1601 		c->cputype = CPU_4KEC;
1602 		c->writecombine = _CACHE_UNCACHED;
1603 		__cpu_name[cpu] = "MIPS 4KEc";
1604 		break;
1605 	case PRID_IMP_4KSC:
1606 	case PRID_IMP_4KSD:
1607 		c->cputype = CPU_4KSC;
1608 		c->writecombine = _CACHE_UNCACHED;
1609 		__cpu_name[cpu] = "MIPS 4KSc";
1610 		break;
1611 	case PRID_IMP_5KC:
1612 		c->cputype = CPU_5KC;
1613 		c->writecombine = _CACHE_UNCACHED;
1614 		__cpu_name[cpu] = "MIPS 5Kc";
1615 		break;
1616 	case PRID_IMP_5KE:
1617 		c->cputype = CPU_5KE;
1618 		c->writecombine = _CACHE_UNCACHED;
1619 		__cpu_name[cpu] = "MIPS 5KE";
1620 		break;
1621 	case PRID_IMP_20KC:
1622 		c->cputype = CPU_20KC;
1623 		c->writecombine = _CACHE_UNCACHED;
1624 		__cpu_name[cpu] = "MIPS 20Kc";
1625 		break;
1626 	case PRID_IMP_24K:
1627 		c->cputype = CPU_24K;
1628 		c->writecombine = _CACHE_UNCACHED;
1629 		__cpu_name[cpu] = "MIPS 24Kc";
1630 		break;
1631 	case PRID_IMP_24KE:
1632 		c->cputype = CPU_24K;
1633 		c->writecombine = _CACHE_UNCACHED;
1634 		__cpu_name[cpu] = "MIPS 24KEc";
1635 		break;
1636 	case PRID_IMP_25KF:
1637 		c->cputype = CPU_25KF;
1638 		c->writecombine = _CACHE_UNCACHED;
1639 		__cpu_name[cpu] = "MIPS 25Kc";
1640 		break;
1641 	case PRID_IMP_34K:
1642 		c->cputype = CPU_34K;
1643 		c->writecombine = _CACHE_UNCACHED;
1644 		__cpu_name[cpu] = "MIPS 34Kc";
1645 		cpu_set_mt_per_tc_perf(c);
1646 		break;
1647 	case PRID_IMP_74K:
1648 		c->cputype = CPU_74K;
1649 		c->writecombine = _CACHE_UNCACHED;
1650 		__cpu_name[cpu] = "MIPS 74Kc";
1651 		break;
1652 	case PRID_IMP_M14KC:
1653 		c->cputype = CPU_M14KC;
1654 		c->writecombine = _CACHE_UNCACHED;
1655 		__cpu_name[cpu] = "MIPS M14Kc";
1656 		break;
1657 	case PRID_IMP_M14KEC:
1658 		c->cputype = CPU_M14KEC;
1659 		c->writecombine = _CACHE_UNCACHED;
1660 		__cpu_name[cpu] = "MIPS M14KEc";
1661 		break;
1662 	case PRID_IMP_1004K:
1663 		c->cputype = CPU_1004K;
1664 		c->writecombine = _CACHE_UNCACHED;
1665 		__cpu_name[cpu] = "MIPS 1004Kc";
1666 		cpu_set_mt_per_tc_perf(c);
1667 		break;
1668 	case PRID_IMP_1074K:
1669 		c->cputype = CPU_1074K;
1670 		c->writecombine = _CACHE_UNCACHED;
1671 		__cpu_name[cpu] = "MIPS 1074Kc";
1672 		break;
1673 	case PRID_IMP_INTERAPTIV_UP:
1674 		c->cputype = CPU_INTERAPTIV;
1675 		__cpu_name[cpu] = "MIPS interAptiv";
1676 		cpu_set_mt_per_tc_perf(c);
1677 		break;
1678 	case PRID_IMP_INTERAPTIV_MP:
1679 		c->cputype = CPU_INTERAPTIV;
1680 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1681 		cpu_set_mt_per_tc_perf(c);
1682 		break;
1683 	case PRID_IMP_PROAPTIV_UP:
1684 		c->cputype = CPU_PROAPTIV;
1685 		__cpu_name[cpu] = "MIPS proAptiv";
1686 		break;
1687 	case PRID_IMP_PROAPTIV_MP:
1688 		c->cputype = CPU_PROAPTIV;
1689 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1690 		break;
1691 	case PRID_IMP_P5600:
1692 		c->cputype = CPU_P5600;
1693 		__cpu_name[cpu] = "MIPS P5600";
1694 		break;
1695 	case PRID_IMP_P6600:
1696 		c->cputype = CPU_P6600;
1697 		__cpu_name[cpu] = "MIPS P6600";
1698 		break;
1699 	case PRID_IMP_I6400:
1700 		c->cputype = CPU_I6400;
1701 		__cpu_name[cpu] = "MIPS I6400";
1702 		break;
1703 	case PRID_IMP_I6500:
1704 		c->cputype = CPU_I6500;
1705 		__cpu_name[cpu] = "MIPS I6500";
1706 		break;
1707 	case PRID_IMP_M5150:
1708 		c->cputype = CPU_M5150;
1709 		__cpu_name[cpu] = "MIPS M5150";
1710 		break;
1711 	case PRID_IMP_M6250:
1712 		c->cputype = CPU_M6250;
1713 		__cpu_name[cpu] = "MIPS M6250";
1714 		break;
1715 	}
1716 
1717 	decode_configs(c);
1718 
1719 	spram_config();
1720 
1721 	switch (__get_cpu_type(c->cputype)) {
1722 	case CPU_I6500:
1723 		c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
1724 		/* fall-through */
1725 	case CPU_I6400:
1726 		c->options |= MIPS_CPU_SHARED_FTLB_RAM;
1727 		/* fall-through */
1728 	default:
1729 		break;
1730 	}
1731 }
1732 
1733 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1734 {
1735 	decode_configs(c);
1736 	switch (c->processor_id & PRID_IMP_MASK) {
1737 	case PRID_IMP_AU1_REV1:
1738 	case PRID_IMP_AU1_REV2:
1739 		c->cputype = CPU_ALCHEMY;
1740 		switch ((c->processor_id >> 24) & 0xff) {
1741 		case 0:
1742 			__cpu_name[cpu] = "Au1000";
1743 			break;
1744 		case 1:
1745 			__cpu_name[cpu] = "Au1500";
1746 			break;
1747 		case 2:
1748 			__cpu_name[cpu] = "Au1100";
1749 			break;
1750 		case 3:
1751 			__cpu_name[cpu] = "Au1550";
1752 			break;
1753 		case 4:
1754 			__cpu_name[cpu] = "Au1200";
1755 			if ((c->processor_id & PRID_REV_MASK) == 2)
1756 				__cpu_name[cpu] = "Au1250";
1757 			break;
1758 		case 5:
1759 			__cpu_name[cpu] = "Au1210";
1760 			break;
1761 		default:
1762 			__cpu_name[cpu] = "Au1xxx";
1763 			break;
1764 		}
1765 		break;
1766 	}
1767 }
1768 
1769 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1770 {
1771 	decode_configs(c);
1772 
1773 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1774 	switch (c->processor_id & PRID_IMP_MASK) {
1775 	case PRID_IMP_SB1:
1776 		c->cputype = CPU_SB1;
1777 		__cpu_name[cpu] = "SiByte SB1";
1778 		/* FPU in pass1 is known to have issues. */
1779 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1780 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1781 		break;
1782 	case PRID_IMP_SB1A:
1783 		c->cputype = CPU_SB1A;
1784 		__cpu_name[cpu] = "SiByte SB1A";
1785 		break;
1786 	}
1787 }
1788 
1789 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1790 {
1791 	decode_configs(c);
1792 	switch (c->processor_id & PRID_IMP_MASK) {
1793 	case PRID_IMP_SR71000:
1794 		c->cputype = CPU_SR71000;
1795 		__cpu_name[cpu] = "Sandcraft SR71000";
1796 		c->scache.ways = 8;
1797 		c->tlbsize = 64;
1798 		break;
1799 	}
1800 }
1801 
1802 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1803 {
1804 	decode_configs(c);
1805 	switch (c->processor_id & PRID_IMP_MASK) {
1806 	case PRID_IMP_PR4450:
1807 		c->cputype = CPU_PR4450;
1808 		__cpu_name[cpu] = "Philips PR4450";
1809 		set_isa(c, MIPS_CPU_ISA_M32R1);
1810 		break;
1811 	}
1812 }
1813 
1814 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1815 {
1816 	decode_configs(c);
1817 	switch (c->processor_id & PRID_IMP_MASK) {
1818 	case PRID_IMP_BMIPS32_REV4:
1819 	case PRID_IMP_BMIPS32_REV8:
1820 		c->cputype = CPU_BMIPS32;
1821 		__cpu_name[cpu] = "Broadcom BMIPS32";
1822 		set_elf_platform(cpu, "bmips32");
1823 		break;
1824 	case PRID_IMP_BMIPS3300:
1825 	case PRID_IMP_BMIPS3300_ALT:
1826 	case PRID_IMP_BMIPS3300_BUG:
1827 		c->cputype = CPU_BMIPS3300;
1828 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1829 		set_elf_platform(cpu, "bmips3300");
1830 		break;
1831 	case PRID_IMP_BMIPS43XX: {
1832 		int rev = c->processor_id & PRID_REV_MASK;
1833 
1834 		if (rev >= PRID_REV_BMIPS4380_LO &&
1835 				rev <= PRID_REV_BMIPS4380_HI) {
1836 			c->cputype = CPU_BMIPS4380;
1837 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1838 			set_elf_platform(cpu, "bmips4380");
1839 			c->options |= MIPS_CPU_RIXI;
1840 		} else {
1841 			c->cputype = CPU_BMIPS4350;
1842 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1843 			set_elf_platform(cpu, "bmips4350");
1844 		}
1845 		break;
1846 	}
1847 	case PRID_IMP_BMIPS5000:
1848 	case PRID_IMP_BMIPS5200:
1849 		c->cputype = CPU_BMIPS5000;
1850 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1851 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1852 		else
1853 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1854 		set_elf_platform(cpu, "bmips5000");
1855 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1856 		break;
1857 	}
1858 }
1859 
1860 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1861 {
1862 	decode_configs(c);
1863 	switch (c->processor_id & PRID_IMP_MASK) {
1864 	case PRID_IMP_CAVIUM_CN38XX:
1865 	case PRID_IMP_CAVIUM_CN31XX:
1866 	case PRID_IMP_CAVIUM_CN30XX:
1867 		c->cputype = CPU_CAVIUM_OCTEON;
1868 		__cpu_name[cpu] = "Cavium Octeon";
1869 		goto platform;
1870 	case PRID_IMP_CAVIUM_CN58XX:
1871 	case PRID_IMP_CAVIUM_CN56XX:
1872 	case PRID_IMP_CAVIUM_CN50XX:
1873 	case PRID_IMP_CAVIUM_CN52XX:
1874 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1875 		__cpu_name[cpu] = "Cavium Octeon+";
1876 platform:
1877 		set_elf_platform(cpu, "octeon");
1878 		break;
1879 	case PRID_IMP_CAVIUM_CN61XX:
1880 	case PRID_IMP_CAVIUM_CN63XX:
1881 	case PRID_IMP_CAVIUM_CN66XX:
1882 	case PRID_IMP_CAVIUM_CN68XX:
1883 	case PRID_IMP_CAVIUM_CNF71XX:
1884 		c->cputype = CPU_CAVIUM_OCTEON2;
1885 		__cpu_name[cpu] = "Cavium Octeon II";
1886 		set_elf_platform(cpu, "octeon2");
1887 		break;
1888 	case PRID_IMP_CAVIUM_CN70XX:
1889 	case PRID_IMP_CAVIUM_CN73XX:
1890 	case PRID_IMP_CAVIUM_CNF75XX:
1891 	case PRID_IMP_CAVIUM_CN78XX:
1892 		c->cputype = CPU_CAVIUM_OCTEON3;
1893 		__cpu_name[cpu] = "Cavium Octeon III";
1894 		set_elf_platform(cpu, "octeon3");
1895 		break;
1896 	default:
1897 		printk(KERN_INFO "Unknown Octeon chip!\n");
1898 		c->cputype = CPU_UNKNOWN;
1899 		break;
1900 	}
1901 }
1902 
1903 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
1904 {
1905 	switch (c->processor_id & PRID_IMP_MASK) {
1906 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
1907 		switch (c->processor_id & PRID_REV_MASK) {
1908 		case PRID_REV_LOONGSON3A_R2_0:
1909 		case PRID_REV_LOONGSON3A_R2_1:
1910 			c->cputype = CPU_LOONGSON3;
1911 			__cpu_name[cpu] = "ICT Loongson-3";
1912 			set_elf_platform(cpu, "loongson3a");
1913 			set_isa(c, MIPS_CPU_ISA_M64R2);
1914 			break;
1915 		case PRID_REV_LOONGSON3A_R3_0:
1916 		case PRID_REV_LOONGSON3A_R3_1:
1917 			c->cputype = CPU_LOONGSON3;
1918 			__cpu_name[cpu] = "ICT Loongson-3";
1919 			set_elf_platform(cpu, "loongson3a");
1920 			set_isa(c, MIPS_CPU_ISA_M64R2);
1921 			break;
1922 		}
1923 
1924 		decode_configs(c);
1925 		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
1926 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1927 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1928 			MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
1929 		break;
1930 	default:
1931 		panic("Unknown Loongson Processor ID!");
1932 		break;
1933 	}
1934 }
1935 
1936 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
1937 {
1938 	decode_configs(c);
1939 
1940 	/*
1941 	 * XBurst misses a config2 register, so config3 decode was skipped in
1942 	 * decode_configs().
1943 	 */
1944 	decode_config3(c);
1945 
1946 	/* XBurst does not implement the CP0 counter. */
1947 	c->options &= ~MIPS_CPU_COUNTER;
1948 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
1949 
1950 	switch (c->processor_id & PRID_IMP_MASK) {
1951 	case PRID_IMP_XBURST:
1952 		c->cputype = CPU_XBURST;
1953 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1954 		__cpu_name[cpu] = "Ingenic JZRISC";
1955 		/*
1956 		 * The XBurst core by default attempts to avoid branch target
1957 		 * buffer lookups by detecting & special casing loops. This
1958 		 * feature will cause BogoMIPS and lpj calculate in error.
1959 		 * Set cp0 config7 bit 4 to disable this feature.
1960 		 */
1961 		set_c0_config7(MIPS_CONF7_BTB_LOOP_EN);
1962 		break;
1963 	default:
1964 		panic("Unknown Ingenic Processor ID!");
1965 		break;
1966 	}
1967 
1968 	/*
1969 	 * The config0 register in the Xburst CPUs with a processor ID of
1970 	 * PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 compatible,
1971 	 * but they don't actually support this ISA.
1972 	 */
1973 	if ((c->processor_id & PRID_COMP_MASK) == PRID_COMP_INGENIC_D0)
1974 		c->isa_level &= ~MIPS_CPU_ISA_M32R2;
1975 }
1976 
1977 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
1978 {
1979 	decode_configs(c);
1980 
1981 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
1982 		c->cputype = CPU_ALCHEMY;
1983 		__cpu_name[cpu] = "Au1300";
1984 		/* following stuff is not for Alchemy */
1985 		return;
1986 	}
1987 
1988 	c->options = (MIPS_CPU_TLB	 |
1989 			MIPS_CPU_4KEX	 |
1990 			MIPS_CPU_COUNTER |
1991 			MIPS_CPU_DIVEC	 |
1992 			MIPS_CPU_WATCH	 |
1993 			MIPS_CPU_EJTAG	 |
1994 			MIPS_CPU_LLSC);
1995 
1996 	switch (c->processor_id & PRID_IMP_MASK) {
1997 	case PRID_IMP_NETLOGIC_XLP2XX:
1998 	case PRID_IMP_NETLOGIC_XLP9XX:
1999 	case PRID_IMP_NETLOGIC_XLP5XX:
2000 		c->cputype = CPU_XLP;
2001 		__cpu_name[cpu] = "Broadcom XLPII";
2002 		break;
2003 
2004 	case PRID_IMP_NETLOGIC_XLP8XX:
2005 	case PRID_IMP_NETLOGIC_XLP3XX:
2006 		c->cputype = CPU_XLP;
2007 		__cpu_name[cpu] = "Netlogic XLP";
2008 		break;
2009 
2010 	case PRID_IMP_NETLOGIC_XLR732:
2011 	case PRID_IMP_NETLOGIC_XLR716:
2012 	case PRID_IMP_NETLOGIC_XLR532:
2013 	case PRID_IMP_NETLOGIC_XLR308:
2014 	case PRID_IMP_NETLOGIC_XLR532C:
2015 	case PRID_IMP_NETLOGIC_XLR516C:
2016 	case PRID_IMP_NETLOGIC_XLR508C:
2017 	case PRID_IMP_NETLOGIC_XLR308C:
2018 		c->cputype = CPU_XLR;
2019 		__cpu_name[cpu] = "Netlogic XLR";
2020 		break;
2021 
2022 	case PRID_IMP_NETLOGIC_XLS608:
2023 	case PRID_IMP_NETLOGIC_XLS408:
2024 	case PRID_IMP_NETLOGIC_XLS404:
2025 	case PRID_IMP_NETLOGIC_XLS208:
2026 	case PRID_IMP_NETLOGIC_XLS204:
2027 	case PRID_IMP_NETLOGIC_XLS108:
2028 	case PRID_IMP_NETLOGIC_XLS104:
2029 	case PRID_IMP_NETLOGIC_XLS616B:
2030 	case PRID_IMP_NETLOGIC_XLS608B:
2031 	case PRID_IMP_NETLOGIC_XLS416B:
2032 	case PRID_IMP_NETLOGIC_XLS412B:
2033 	case PRID_IMP_NETLOGIC_XLS408B:
2034 	case PRID_IMP_NETLOGIC_XLS404B:
2035 		c->cputype = CPU_XLR;
2036 		__cpu_name[cpu] = "Netlogic XLS";
2037 		break;
2038 
2039 	default:
2040 		pr_info("Unknown Netlogic chip id [%02x]!\n",
2041 		       c->processor_id);
2042 		c->cputype = CPU_XLR;
2043 		break;
2044 	}
2045 
2046 	if (c->cputype == CPU_XLP) {
2047 		set_isa(c, MIPS_CPU_ISA_M64R2);
2048 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
2049 		/* This will be updated again after all threads are woken up */
2050 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
2051 	} else {
2052 		set_isa(c, MIPS_CPU_ISA_M64R1);
2053 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
2054 	}
2055 	c->kscratch_mask = 0xf;
2056 }
2057 
2058 #ifdef CONFIG_64BIT
2059 /* For use by uaccess.h */
2060 u64 __ua_limit;
2061 EXPORT_SYMBOL(__ua_limit);
2062 #endif
2063 
2064 const char *__cpu_name[NR_CPUS];
2065 const char *__elf_platform;
2066 
2067 void cpu_probe(void)
2068 {
2069 	struct cpuinfo_mips *c = &current_cpu_data;
2070 	unsigned int cpu = smp_processor_id();
2071 
2072 	/*
2073 	 * Set a default elf platform, cpu probe may later
2074 	 * overwrite it with a more precise value
2075 	 */
2076 	set_elf_platform(cpu, "mips");
2077 
2078 	c->processor_id = PRID_IMP_UNKNOWN;
2079 	c->fpu_id	= FPIR_IMP_NONE;
2080 	c->cputype	= CPU_UNKNOWN;
2081 	c->writecombine = _CACHE_UNCACHED;
2082 
2083 	c->fpu_csr31	= FPU_CSR_RN;
2084 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
2085 
2086 	c->processor_id = read_c0_prid();
2087 	switch (c->processor_id & PRID_COMP_MASK) {
2088 	case PRID_COMP_LEGACY:
2089 		cpu_probe_legacy(c, cpu);
2090 		break;
2091 	case PRID_COMP_MIPS:
2092 		cpu_probe_mips(c, cpu);
2093 		break;
2094 	case PRID_COMP_ALCHEMY:
2095 		cpu_probe_alchemy(c, cpu);
2096 		break;
2097 	case PRID_COMP_SIBYTE:
2098 		cpu_probe_sibyte(c, cpu);
2099 		break;
2100 	case PRID_COMP_BROADCOM:
2101 		cpu_probe_broadcom(c, cpu);
2102 		break;
2103 	case PRID_COMP_SANDCRAFT:
2104 		cpu_probe_sandcraft(c, cpu);
2105 		break;
2106 	case PRID_COMP_NXP:
2107 		cpu_probe_nxp(c, cpu);
2108 		break;
2109 	case PRID_COMP_CAVIUM:
2110 		cpu_probe_cavium(c, cpu);
2111 		break;
2112 	case PRID_COMP_LOONGSON:
2113 		cpu_probe_loongson(c, cpu);
2114 		break;
2115 	case PRID_COMP_INGENIC_D0:
2116 	case PRID_COMP_INGENIC_D1:
2117 	case PRID_COMP_INGENIC_E1:
2118 		cpu_probe_ingenic(c, cpu);
2119 		break;
2120 	case PRID_COMP_NETLOGIC:
2121 		cpu_probe_netlogic(c, cpu);
2122 		break;
2123 	}
2124 
2125 	BUG_ON(!__cpu_name[cpu]);
2126 	BUG_ON(c->cputype == CPU_UNKNOWN);
2127 
2128 	/*
2129 	 * Platform code can force the cpu type to optimize code
2130 	 * generation. In that case be sure the cpu type is correctly
2131 	 * manually setup otherwise it could trigger some nasty bugs.
2132 	 */
2133 	BUG_ON(current_cpu_type() != c->cputype);
2134 
2135 	if (cpu_has_rixi) {
2136 		/* Enable the RIXI exceptions */
2137 		set_c0_pagegrain(PG_IEC);
2138 		back_to_back_c0_hazard();
2139 		/* Verify the IEC bit is set */
2140 		if (read_c0_pagegrain() & PG_IEC)
2141 			c->options |= MIPS_CPU_RIXIEX;
2142 	}
2143 
2144 	if (mips_fpu_disabled)
2145 		c->options &= ~MIPS_CPU_FPU;
2146 
2147 	if (mips_dsp_disabled)
2148 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2149 
2150 	if (mips_htw_disabled) {
2151 		c->options &= ~MIPS_CPU_HTW;
2152 		write_c0_pwctl(read_c0_pwctl() &
2153 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2154 	}
2155 
2156 	if (c->options & MIPS_CPU_FPU)
2157 		cpu_set_fpu_opts(c);
2158 	else
2159 		cpu_set_nofpu_opts(c);
2160 
2161 	if (cpu_has_bp_ghist)
2162 		write_c0_r10k_diag(read_c0_r10k_diag() |
2163 				   R10K_DIAG_E_GHIST);
2164 
2165 	if (cpu_has_mips_r2_r6) {
2166 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2167 		/* R2 has Performance Counter Interrupt indicator */
2168 		c->options |= MIPS_CPU_PCI;
2169 	}
2170 	else
2171 		c->srsets = 1;
2172 
2173 	if (cpu_has_mips_r6)
2174 		elf_hwcap |= HWCAP_MIPS_R6;
2175 
2176 	if (cpu_has_msa) {
2177 		c->msa_id = cpu_get_msa_id();
2178 		WARN(c->msa_id & MSA_IR_WRPF,
2179 		     "Vector register partitioning unimplemented!");
2180 		elf_hwcap |= HWCAP_MIPS_MSA;
2181 	}
2182 
2183 	if (cpu_has_vz)
2184 		cpu_probe_vz(c);
2185 
2186 	cpu_probe_vmbits(c);
2187 
2188 #ifdef CONFIG_64BIT
2189 	if (cpu == 0)
2190 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2191 #endif
2192 }
2193 
2194 void cpu_report(void)
2195 {
2196 	struct cpuinfo_mips *c = &current_cpu_data;
2197 
2198 	pr_info("CPU%d revision is: %08x (%s)\n",
2199 		smp_processor_id(), c->processor_id, cpu_name_string());
2200 	if (c->options & MIPS_CPU_FPU)
2201 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2202 	if (cpu_has_msa)
2203 		pr_info("MSA revision is: %08x\n", c->msa_id);
2204 }
2205 
2206 void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
2207 {
2208 	/* Ensure the core number fits in the field */
2209 	WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
2210 			   MIPS_GLOBALNUMBER_CLUSTER_SHF));
2211 
2212 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
2213 	cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
2214 }
2215 
2216 void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
2217 {
2218 	/* Ensure the core number fits in the field */
2219 	WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
2220 
2221 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
2222 	cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
2223 }
2224 
2225 void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
2226 {
2227 	/* Ensure the VP(E) ID fits in the field */
2228 	WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
2229 
2230 	/* Ensure we're not using VP(E)s without support */
2231 	WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
2232 		!IS_ENABLED(CONFIG_CPU_MIPSR6));
2233 
2234 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
2235 	cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
2236 }
2237