xref: /openbmc/linux/arch/mips/kernel/cpu-probe.c (revision 1d27a0be)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Processor capabilities determination functions.
4  *
5  * Copyright (C) xxxx  the Anonymous
6  * Copyright (C) 1994 - 2006 Ralf Baechle
7  * Copyright (C) 2003, 2004  Maciej W. Rozycki
8  * Copyright (C) 2001, 2004, 2011, 2012	 MIPS Technologies, Inc.
9  */
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/ptrace.h>
13 #include <linux/smp.h>
14 #include <linux/stddef.h>
15 #include <linux/export.h>
16 
17 #include <asm/bugs.h>
18 #include <asm/cpu.h>
19 #include <asm/cpu-features.h>
20 #include <asm/cpu-type.h>
21 #include <asm/fpu.h>
22 #include <asm/mipsregs.h>
23 #include <asm/mipsmtregs.h>
24 #include <asm/msa.h>
25 #include <asm/watch.h>
26 #include <asm/elf.h>
27 #include <asm/pgtable-bits.h>
28 #include <asm/spram.h>
29 #include <linux/uaccess.h>
30 
31 #include <asm/mach-loongson64/cpucfg-emul.h>
32 
33 /* Hardware capabilities */
34 unsigned int elf_hwcap __read_mostly;
35 EXPORT_SYMBOL_GPL(elf_hwcap);
36 
37 #ifdef CONFIG_MIPS_FP_SUPPORT
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 /*
62  * Determine the FCSR mask for FPU hardware.
63  */
64 static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_mips *c)
65 {
66 	unsigned long sr, mask, fcsr, fcsr0, fcsr1;
67 
68 	fcsr = c->fpu_csr31;
69 	mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
70 
71 	sr = read_c0_status();
72 	__enable_fpu(FPU_AS_IS);
73 
74 	fcsr0 = fcsr & mask;
75 	write_32bit_cp1_register(CP1_STATUS, fcsr0);
76 	fcsr0 = read_32bit_cp1_register(CP1_STATUS);
77 
78 	fcsr1 = fcsr | ~mask;
79 	write_32bit_cp1_register(CP1_STATUS, fcsr1);
80 	fcsr1 = read_32bit_cp1_register(CP1_STATUS);
81 
82 	write_32bit_cp1_register(CP1_STATUS, fcsr);
83 
84 	write_c0_status(sr);
85 
86 	c->fpu_msk31 = ~(fcsr0 ^ fcsr1) & ~mask;
87 }
88 
89 /*
90  * Determine the IEEE 754 NaN encodings and ABS.fmt/NEG.fmt execution modes
91  * supported by FPU hardware.
92  */
93 static void cpu_set_fpu_2008(struct cpuinfo_mips *c)
94 {
95 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
96 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
97 			    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
98 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
99 		unsigned long sr, fir, fcsr, fcsr0, fcsr1;
100 
101 		sr = read_c0_status();
102 		__enable_fpu(FPU_AS_IS);
103 
104 		fir = read_32bit_cp1_register(CP1_REVISION);
105 		if (fir & MIPS_FPIR_HAS2008) {
106 			fcsr = read_32bit_cp1_register(CP1_STATUS);
107 
108 			/*
109 			 * MAC2008 toolchain never landed in real world, so we're only
110 			 * testing wether it can be disabled and don't try to enabled
111 			 * it.
112 			 */
113 			fcsr0 = fcsr & ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008 | FPU_CSR_MAC2008);
114 			write_32bit_cp1_register(CP1_STATUS, fcsr0);
115 			fcsr0 = read_32bit_cp1_register(CP1_STATUS);
116 
117 			fcsr1 = fcsr | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
118 			write_32bit_cp1_register(CP1_STATUS, fcsr1);
119 			fcsr1 = read_32bit_cp1_register(CP1_STATUS);
120 
121 			write_32bit_cp1_register(CP1_STATUS, fcsr);
122 
123 			if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2)) {
124 				/*
125 				 * The bit for MAC2008 might be reused by R6 in future,
126 				 * so we only test for R2-R5.
127 				 */
128 				if (fcsr0 & FPU_CSR_MAC2008)
129 					c->options |= MIPS_CPU_MAC_2008_ONLY;
130 			}
131 
132 			if (!(fcsr0 & FPU_CSR_NAN2008))
133 				c->options |= MIPS_CPU_NAN_LEGACY;
134 			if (fcsr1 & FPU_CSR_NAN2008)
135 				c->options |= MIPS_CPU_NAN_2008;
136 
137 			if ((fcsr0 ^ fcsr1) & FPU_CSR_ABS2008)
138 				c->fpu_msk31 &= ~FPU_CSR_ABS2008;
139 			else
140 				c->fpu_csr31 |= fcsr & FPU_CSR_ABS2008;
141 
142 			if ((fcsr0 ^ fcsr1) & FPU_CSR_NAN2008)
143 				c->fpu_msk31 &= ~FPU_CSR_NAN2008;
144 			else
145 				c->fpu_csr31 |= fcsr & FPU_CSR_NAN2008;
146 		} else {
147 			c->options |= MIPS_CPU_NAN_LEGACY;
148 		}
149 
150 		write_c0_status(sr);
151 	} else {
152 		c->options |= MIPS_CPU_NAN_LEGACY;
153 	}
154 }
155 
156 /*
157  * IEEE 754 conformance mode to use.  Affects the NaN encoding and the
158  * ABS.fmt/NEG.fmt execution mode.
159  */
160 static enum { STRICT, LEGACY, STD2008, RELAXED } ieee754 = STRICT;
161 
162 /*
163  * Set the IEEE 754 NaN encodings and the ABS.fmt/NEG.fmt execution modes
164  * to support by the FPU emulator according to the IEEE 754 conformance
165  * mode selected.  Note that "relaxed" straps the emulator so that it
166  * allows 2008-NaN binaries even for legacy processors.
167  */
168 static void cpu_set_nofpu_2008(struct cpuinfo_mips *c)
169 {
170 	c->options &= ~(MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY);
171 	c->fpu_csr31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
172 	c->fpu_msk31 &= ~(FPU_CSR_ABS2008 | FPU_CSR_NAN2008);
173 
174 	switch (ieee754) {
175 	case STRICT:
176 		if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
177 				    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
178 				    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
179 				    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
180 			c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
181 		} else {
182 			c->options |= MIPS_CPU_NAN_LEGACY;
183 			c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
184 		}
185 		break;
186 	case LEGACY:
187 		c->options |= MIPS_CPU_NAN_LEGACY;
188 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
189 		break;
190 	case STD2008:
191 		c->options |= MIPS_CPU_NAN_2008;
192 		c->fpu_csr31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
193 		c->fpu_msk31 |= FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
194 		break;
195 	case RELAXED:
196 		c->options |= MIPS_CPU_NAN_2008 | MIPS_CPU_NAN_LEGACY;
197 		break;
198 	}
199 }
200 
201 /*
202  * Override the IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode
203  * according to the "ieee754=" parameter.
204  */
205 static void cpu_set_nan_2008(struct cpuinfo_mips *c)
206 {
207 	switch (ieee754) {
208 	case STRICT:
209 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
210 		mips_use_nan_2008 = !!cpu_has_nan_2008;
211 		break;
212 	case LEGACY:
213 		mips_use_nan_legacy = !!cpu_has_nan_legacy;
214 		mips_use_nan_2008 = !cpu_has_nan_legacy;
215 		break;
216 	case STD2008:
217 		mips_use_nan_legacy = !cpu_has_nan_2008;
218 		mips_use_nan_2008 = !!cpu_has_nan_2008;
219 		break;
220 	case RELAXED:
221 		mips_use_nan_legacy = true;
222 		mips_use_nan_2008 = true;
223 		break;
224 	}
225 }
226 
227 /*
228  * IEEE 754 NaN encoding and ABS.fmt/NEG.fmt execution mode override
229  * settings:
230  *
231  * strict:  accept binaries that request a NaN encoding supported by the FPU
232  * legacy:  only accept legacy-NaN binaries
233  * 2008:    only accept 2008-NaN binaries
234  * relaxed: accept any binaries regardless of whether supported by the FPU
235  */
236 static int __init ieee754_setup(char *s)
237 {
238 	if (!s)
239 		return -1;
240 	else if (!strcmp(s, "strict"))
241 		ieee754 = STRICT;
242 	else if (!strcmp(s, "legacy"))
243 		ieee754 = LEGACY;
244 	else if (!strcmp(s, "2008"))
245 		ieee754 = STD2008;
246 	else if (!strcmp(s, "relaxed"))
247 		ieee754 = RELAXED;
248 	else
249 		return -1;
250 
251 	if (!(boot_cpu_data.options & MIPS_CPU_FPU))
252 		cpu_set_nofpu_2008(&boot_cpu_data);
253 	cpu_set_nan_2008(&boot_cpu_data);
254 
255 	return 0;
256 }
257 
258 early_param("ieee754", ieee754_setup);
259 
260 /*
261  * Set the FIR feature flags for the FPU emulator.
262  */
263 static void cpu_set_nofpu_id(struct cpuinfo_mips *c)
264 {
265 	u32 value;
266 
267 	value = 0;
268 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
269 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
270 			    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
271 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
272 		value |= MIPS_FPIR_D | MIPS_FPIR_S;
273 	if (c->isa_level & (MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
274 			    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
275 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6))
276 		value |= MIPS_FPIR_F64 | MIPS_FPIR_L | MIPS_FPIR_W;
277 	if (c->options & MIPS_CPU_NAN_2008)
278 		value |= MIPS_FPIR_HAS2008;
279 	c->fpu_id = value;
280 }
281 
282 /* Determined FPU emulator mask to use for the boot CPU with "nofpu".  */
283 static unsigned int mips_nofpu_msk31;
284 
285 /*
286  * Set options for FPU hardware.
287  */
288 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
289 {
290 	c->fpu_id = cpu_get_fpu_id();
291 	mips_nofpu_msk31 = c->fpu_msk31;
292 
293 	if (c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1 |
294 			    MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2 |
295 			    MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5 |
296 			    MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6)) {
297 		if (c->fpu_id & MIPS_FPIR_3D)
298 			c->ases |= MIPS_ASE_MIPS3D;
299 		if (c->fpu_id & MIPS_FPIR_UFRP)
300 			c->options |= MIPS_CPU_UFR;
301 		if (c->fpu_id & MIPS_FPIR_FREP)
302 			c->options |= MIPS_CPU_FRE;
303 	}
304 
305 	cpu_set_fpu_fcsr_mask(c);
306 	cpu_set_fpu_2008(c);
307 	cpu_set_nan_2008(c);
308 }
309 
310 /*
311  * Set options for the FPU emulator.
312  */
313 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
314 {
315 	c->options &= ~MIPS_CPU_FPU;
316 	c->fpu_msk31 = mips_nofpu_msk31;
317 
318 	cpu_set_nofpu_2008(c);
319 	cpu_set_nan_2008(c);
320 	cpu_set_nofpu_id(c);
321 }
322 
323 static int mips_fpu_disabled;
324 
325 static int __init fpu_disable(char *s)
326 {
327 	cpu_set_nofpu_opts(&boot_cpu_data);
328 	mips_fpu_disabled = 1;
329 
330 	return 1;
331 }
332 
333 __setup("nofpu", fpu_disable);
334 
335 #else /* !CONFIG_MIPS_FP_SUPPORT */
336 
337 #define mips_fpu_disabled 1
338 
339 static inline unsigned long cpu_get_fpu_id(void)
340 {
341 	return FPIR_IMP_NONE;
342 }
343 
344 static inline int __cpu_has_fpu(void)
345 {
346 	return 0;
347 }
348 
349 static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
350 {
351 	/* no-op */
352 }
353 
354 static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
355 {
356 	/* no-op */
357 }
358 
359 #endif /* CONFIG_MIPS_FP_SUPPORT */
360 
361 static inline unsigned long cpu_get_msa_id(void)
362 {
363 	unsigned long status, msa_id;
364 
365 	status = read_c0_status();
366 	__enable_fpu(FPU_64BIT);
367 	enable_msa();
368 	msa_id = read_msa_ir();
369 	disable_msa();
370 	write_c0_status(status);
371 	return msa_id;
372 }
373 
374 static int mips_dsp_disabled;
375 
376 static int __init dsp_disable(char *s)
377 {
378 	cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
379 	mips_dsp_disabled = 1;
380 
381 	return 1;
382 }
383 
384 __setup("nodsp", dsp_disable);
385 
386 static int mips_htw_disabled;
387 
388 static int __init htw_disable(char *s)
389 {
390 	mips_htw_disabled = 1;
391 	cpu_data[0].options &= ~MIPS_CPU_HTW;
392 	write_c0_pwctl(read_c0_pwctl() &
393 		       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
394 
395 	return 1;
396 }
397 
398 __setup("nohtw", htw_disable);
399 
400 static int mips_ftlb_disabled;
401 static int mips_has_ftlb_configured;
402 
403 enum ftlb_flags {
404 	FTLB_EN		= 1 << 0,
405 	FTLB_SET_PROB	= 1 << 1,
406 };
407 
408 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
409 
410 static int __init ftlb_disable(char *s)
411 {
412 	unsigned int config4, mmuextdef;
413 
414 	/*
415 	 * If the core hasn't done any FTLB configuration, there is nothing
416 	 * for us to do here.
417 	 */
418 	if (!mips_has_ftlb_configured)
419 		return 1;
420 
421 	/* Disable it in the boot cpu */
422 	if (set_ftlb_enable(&cpu_data[0], 0)) {
423 		pr_warn("Can't turn FTLB off\n");
424 		return 1;
425 	}
426 
427 	config4 = read_c0_config4();
428 
429 	/* Check that FTLB has been disabled */
430 	mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
431 	/* MMUSIZEEXT == VTLB ON, FTLB OFF */
432 	if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
433 		/* This should never happen */
434 		pr_warn("FTLB could not be disabled!\n");
435 		return 1;
436 	}
437 
438 	mips_ftlb_disabled = 1;
439 	mips_has_ftlb_configured = 0;
440 
441 	/*
442 	 * noftlb is mainly used for debug purposes so print
443 	 * an informative message instead of using pr_debug()
444 	 */
445 	pr_info("FTLB has been disabled\n");
446 
447 	/*
448 	 * Some of these bits are duplicated in the decode_config4.
449 	 * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
450 	 * once FTLB has been disabled so undo what decode_config4 did.
451 	 */
452 	cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
453 			       cpu_data[0].tlbsizeftlbsets;
454 	cpu_data[0].tlbsizeftlbsets = 0;
455 	cpu_data[0].tlbsizeftlbways = 0;
456 
457 	return 1;
458 }
459 
460 __setup("noftlb", ftlb_disable);
461 
462 /*
463  * Check if the CPU has per tc perf counters
464  */
465 static inline void cpu_set_mt_per_tc_perf(struct cpuinfo_mips *c)
466 {
467 	if (read_c0_config7() & MTI_CONF7_PTC)
468 		c->options |= MIPS_CPU_MT_PER_TC_PERF_COUNTERS;
469 }
470 
471 static inline void check_errata(void)
472 {
473 	struct cpuinfo_mips *c = &current_cpu_data;
474 
475 	switch (current_cpu_type()) {
476 	case CPU_34K:
477 		/*
478 		 * Erratum "RPS May Cause Incorrect Instruction Execution"
479 		 * This code only handles VPE0, any SMP/RTOS code
480 		 * making use of VPE1 will be responsable for that VPE.
481 		 */
482 		if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
483 			write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
484 		break;
485 	default:
486 		break;
487 	}
488 }
489 
490 void __init check_bugs32(void)
491 {
492 	check_errata();
493 }
494 
495 /*
496  * Probe whether cpu has config register by trying to play with
497  * alternate cache bit and see whether it matters.
498  * It's used by cpu_probe to distinguish between R3000A and R3081.
499  */
500 static inline int cpu_has_confreg(void)
501 {
502 #ifdef CONFIG_CPU_R3000
503 	extern unsigned long r3k_cache_size(unsigned long);
504 	unsigned long size1, size2;
505 	unsigned long cfg = read_c0_conf();
506 
507 	size1 = r3k_cache_size(ST0_ISC);
508 	write_c0_conf(cfg ^ R30XX_CONF_AC);
509 	size2 = r3k_cache_size(ST0_ISC);
510 	write_c0_conf(cfg);
511 	return size1 != size2;
512 #else
513 	return 0;
514 #endif
515 }
516 
517 static inline void set_elf_platform(int cpu, const char *plat)
518 {
519 	if (cpu == 0)
520 		__elf_platform = plat;
521 }
522 
523 static inline void set_elf_base_platform(const char *plat)
524 {
525 	if (__elf_base_platform == NULL) {
526 		__elf_base_platform = plat;
527 	}
528 }
529 
530 static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
531 {
532 #ifdef __NEED_VMBITS_PROBE
533 	write_c0_entryhi(0x3fffffffffffe000ULL);
534 	back_to_back_c0_hazard();
535 	c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
536 #endif
537 }
538 
539 static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
540 {
541 	switch (isa) {
542 	case MIPS_CPU_ISA_M64R5:
543 		c->isa_level |= MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5;
544 		set_elf_base_platform("mips64r5");
545 		fallthrough;
546 	case MIPS_CPU_ISA_M64R2:
547 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
548 		set_elf_base_platform("mips64r2");
549 		fallthrough;
550 	case MIPS_CPU_ISA_M64R1:
551 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
552 		set_elf_base_platform("mips64");
553 		fallthrough;
554 	case MIPS_CPU_ISA_V:
555 		c->isa_level |= MIPS_CPU_ISA_V;
556 		set_elf_base_platform("mips5");
557 		fallthrough;
558 	case MIPS_CPU_ISA_IV:
559 		c->isa_level |= MIPS_CPU_ISA_IV;
560 		set_elf_base_platform("mips4");
561 		fallthrough;
562 	case MIPS_CPU_ISA_III:
563 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
564 		set_elf_base_platform("mips3");
565 		break;
566 
567 	/* R6 incompatible with everything else */
568 	case MIPS_CPU_ISA_M64R6:
569 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
570 		set_elf_base_platform("mips64r6");
571 		fallthrough;
572 	case MIPS_CPU_ISA_M32R6:
573 		c->isa_level |= MIPS_CPU_ISA_M32R6;
574 		set_elf_base_platform("mips32r6");
575 		/* Break here so we don't add incompatible ISAs */
576 		break;
577 	case MIPS_CPU_ISA_M32R5:
578 		c->isa_level |= MIPS_CPU_ISA_M32R5;
579 		set_elf_base_platform("mips32r5");
580 		fallthrough;
581 	case MIPS_CPU_ISA_M32R2:
582 		c->isa_level |= MIPS_CPU_ISA_M32R2;
583 		set_elf_base_platform("mips32r2");
584 		fallthrough;
585 	case MIPS_CPU_ISA_M32R1:
586 		c->isa_level |= MIPS_CPU_ISA_M32R1;
587 		set_elf_base_platform("mips32");
588 		fallthrough;
589 	case MIPS_CPU_ISA_II:
590 		c->isa_level |= MIPS_CPU_ISA_II;
591 		set_elf_base_platform("mips2");
592 		break;
593 	}
594 }
595 
596 static char unknown_isa[] = KERN_ERR \
597 	"Unsupported ISA type, c0.config0: %d.";
598 
599 static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
600 {
601 
602 	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
603 
604 	/*
605 	 * 0 = All TLBWR instructions go to FTLB
606 	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
607 	 * FTLB and 1 goes to the VTLB.
608 	 * 2 = 7:1: As above with 7:1 ratio.
609 	 * 3 = 3:1: As above with 3:1 ratio.
610 	 *
611 	 * Use the linear midpoint as the probability threshold.
612 	 */
613 	if (probability >= 12)
614 		return 1;
615 	else if (probability >= 6)
616 		return 2;
617 	else
618 		/*
619 		 * So FTLB is less than 4 times bigger than VTLB.
620 		 * A 3:1 ratio can still be useful though.
621 		 */
622 		return 3;
623 }
624 
625 static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
626 {
627 	unsigned int config;
628 
629 	/* It's implementation dependent how the FTLB can be enabled */
630 	switch (c->cputype) {
631 	case CPU_PROAPTIV:
632 	case CPU_P5600:
633 	case CPU_P6600:
634 		/* proAptiv & related cores use Config6 to enable the FTLB */
635 		config = read_c0_config6();
636 
637 		if (flags & FTLB_EN)
638 			config |= MIPS_CONF6_MTI_FTLBEN;
639 		else
640 			config &= ~MIPS_CONF6_MTI_FTLBEN;
641 
642 		if (flags & FTLB_SET_PROB) {
643 			config &= ~(3 << MIPS_CONF6_MTI_FTLBP_SHIFT);
644 			config |= calculate_ftlb_probability(c)
645 				  << MIPS_CONF6_MTI_FTLBP_SHIFT;
646 		}
647 
648 		write_c0_config6(config);
649 		back_to_back_c0_hazard();
650 		break;
651 	case CPU_I6400:
652 	case CPU_I6500:
653 		/* There's no way to disable the FTLB */
654 		if (!(flags & FTLB_EN))
655 			return 1;
656 		return 0;
657 	case CPU_LOONGSON64:
658 		/* Flush ITLB, DTLB, VTLB and FTLB */
659 		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
660 			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
661 		/* Loongson-3 cores use Config6 to enable the FTLB */
662 		config = read_c0_config6();
663 		if (flags & FTLB_EN)
664 			/* Enable FTLB */
665 			write_c0_config6(config & ~MIPS_CONF6_LOONGSON_FTLBDIS);
666 		else
667 			/* Disable FTLB */
668 			write_c0_config6(config | MIPS_CONF6_LOONGSON_FTLBDIS);
669 		break;
670 	default:
671 		return 1;
672 	}
673 
674 	return 0;
675 }
676 
677 static int mm_config(struct cpuinfo_mips *c)
678 {
679 	unsigned int config0, update, mm;
680 
681 	config0 = read_c0_config();
682 	mm = config0 & MIPS_CONF_MM;
683 
684 	/*
685 	 * It's implementation dependent what type of write-merge is supported
686 	 * and whether it can be enabled/disabled. If it is settable lets make
687 	 * the merging allowed by default. Some platforms might have
688 	 * write-through caching unsupported. In this case just ignore the
689 	 * CP0.Config.MM bit field value.
690 	 */
691 	switch (c->cputype) {
692 	case CPU_24K:
693 	case CPU_34K:
694 	case CPU_74K:
695 	case CPU_P5600:
696 	case CPU_P6600:
697 		c->options |= MIPS_CPU_MM_FULL;
698 		update = MIPS_CONF_MM_FULL;
699 		break;
700 	case CPU_1004K:
701 	case CPU_1074K:
702 	case CPU_INTERAPTIV:
703 	case CPU_PROAPTIV:
704 		mm = 0;
705 		fallthrough;
706 	default:
707 		update = 0;
708 		break;
709 	}
710 
711 	if (update) {
712 		config0 = (config0 & ~MIPS_CONF_MM) | update;
713 		write_c0_config(config0);
714 	} else if (mm == MIPS_CONF_MM_SYSAD) {
715 		c->options |= MIPS_CPU_MM_SYSAD;
716 	} else if (mm == MIPS_CONF_MM_FULL) {
717 		c->options |= MIPS_CPU_MM_FULL;
718 	}
719 
720 	return 0;
721 }
722 
723 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
724 {
725 	unsigned int config0;
726 	int isa, mt;
727 
728 	config0 = read_c0_config();
729 
730 	/*
731 	 * Look for Standard TLB or Dual VTLB and FTLB
732 	 */
733 	mt = config0 & MIPS_CONF_MT;
734 	if (mt == MIPS_CONF_MT_TLB)
735 		c->options |= MIPS_CPU_TLB;
736 	else if (mt == MIPS_CONF_MT_FTLB)
737 		c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
738 
739 	isa = (config0 & MIPS_CONF_AT) >> 13;
740 	switch (isa) {
741 	case 0:
742 		switch ((config0 & MIPS_CONF_AR) >> 10) {
743 		case 0:
744 			set_isa(c, MIPS_CPU_ISA_M32R1);
745 			break;
746 		case 1:
747 			set_isa(c, MIPS_CPU_ISA_M32R2);
748 			break;
749 		case 2:
750 			set_isa(c, MIPS_CPU_ISA_M32R6);
751 			break;
752 		default:
753 			goto unknown;
754 		}
755 		break;
756 	case 2:
757 		switch ((config0 & MIPS_CONF_AR) >> 10) {
758 		case 0:
759 			set_isa(c, MIPS_CPU_ISA_M64R1);
760 			break;
761 		case 1:
762 			set_isa(c, MIPS_CPU_ISA_M64R2);
763 			break;
764 		case 2:
765 			set_isa(c, MIPS_CPU_ISA_M64R6);
766 			break;
767 		default:
768 			goto unknown;
769 		}
770 		break;
771 	default:
772 		goto unknown;
773 	}
774 
775 	return config0 & MIPS_CONF_M;
776 
777 unknown:
778 	panic(unknown_isa, config0);
779 }
780 
781 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
782 {
783 	unsigned int config1;
784 
785 	config1 = read_c0_config1();
786 
787 	if (config1 & MIPS_CONF1_MD)
788 		c->ases |= MIPS_ASE_MDMX;
789 	if (config1 & MIPS_CONF1_PC)
790 		c->options |= MIPS_CPU_PERF;
791 	if (config1 & MIPS_CONF1_WR)
792 		c->options |= MIPS_CPU_WATCH;
793 	if (config1 & MIPS_CONF1_CA)
794 		c->ases |= MIPS_ASE_MIPS16;
795 	if (config1 & MIPS_CONF1_EP)
796 		c->options |= MIPS_CPU_EJTAG;
797 	if (config1 & MIPS_CONF1_FP) {
798 		c->options |= MIPS_CPU_FPU;
799 		c->options |= MIPS_CPU_32FPR;
800 	}
801 	if (cpu_has_tlb) {
802 		c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
803 		c->tlbsizevtlb = c->tlbsize;
804 		c->tlbsizeftlbsets = 0;
805 	}
806 
807 	return config1 & MIPS_CONF_M;
808 }
809 
810 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
811 {
812 	unsigned int config2;
813 
814 	config2 = read_c0_config2();
815 
816 	if (config2 & MIPS_CONF2_SL)
817 		c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
818 
819 	return config2 & MIPS_CONF_M;
820 }
821 
822 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
823 {
824 	unsigned int config3;
825 
826 	config3 = read_c0_config3();
827 
828 	if (config3 & MIPS_CONF3_SM) {
829 		c->ases |= MIPS_ASE_SMARTMIPS;
830 		c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
831 	}
832 	if (config3 & MIPS_CONF3_RXI)
833 		c->options |= MIPS_CPU_RIXI;
834 	if (config3 & MIPS_CONF3_CTXTC)
835 		c->options |= MIPS_CPU_CTXTC;
836 	if (config3 & MIPS_CONF3_DSP)
837 		c->ases |= MIPS_ASE_DSP;
838 	if (config3 & MIPS_CONF3_DSP2P) {
839 		c->ases |= MIPS_ASE_DSP2P;
840 		if (cpu_has_mips_r6)
841 			c->ases |= MIPS_ASE_DSP3;
842 	}
843 	if (config3 & MIPS_CONF3_VINT)
844 		c->options |= MIPS_CPU_VINT;
845 	if (config3 & MIPS_CONF3_VEIC)
846 		c->options |= MIPS_CPU_VEIC;
847 	if (config3 & MIPS_CONF3_LPA)
848 		c->options |= MIPS_CPU_LPA;
849 	if (config3 & MIPS_CONF3_MT)
850 		c->ases |= MIPS_ASE_MIPSMT;
851 	if (config3 & MIPS_CONF3_ULRI)
852 		c->options |= MIPS_CPU_ULRI;
853 	if (config3 & MIPS_CONF3_ISA)
854 		c->options |= MIPS_CPU_MICROMIPS;
855 	if (config3 & MIPS_CONF3_VZ)
856 		c->ases |= MIPS_ASE_VZ;
857 	if (config3 & MIPS_CONF3_SC)
858 		c->options |= MIPS_CPU_SEGMENTS;
859 	if (config3 & MIPS_CONF3_BI)
860 		c->options |= MIPS_CPU_BADINSTR;
861 	if (config3 & MIPS_CONF3_BP)
862 		c->options |= MIPS_CPU_BADINSTRP;
863 	if (config3 & MIPS_CONF3_MSA)
864 		c->ases |= MIPS_ASE_MSA;
865 	if (config3 & MIPS_CONF3_PW) {
866 		c->htw_seq = 0;
867 		c->options |= MIPS_CPU_HTW;
868 	}
869 	if (config3 & MIPS_CONF3_CDMM)
870 		c->options |= MIPS_CPU_CDMM;
871 	if (config3 & MIPS_CONF3_SP)
872 		c->options |= MIPS_CPU_SP;
873 
874 	return config3 & MIPS_CONF_M;
875 }
876 
877 static inline unsigned int decode_config4(struct cpuinfo_mips *c)
878 {
879 	unsigned int config4;
880 	unsigned int newcf4;
881 	unsigned int mmuextdef;
882 	unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
883 	unsigned long asid_mask;
884 
885 	config4 = read_c0_config4();
886 
887 	if (cpu_has_tlb) {
888 		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
889 			c->options |= MIPS_CPU_TLBINV;
890 
891 		/*
892 		 * R6 has dropped the MMUExtDef field from config4.
893 		 * On R6 the fields always describe the FTLB, and only if it is
894 		 * present according to Config.MT.
895 		 */
896 		if (!cpu_has_mips_r6)
897 			mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
898 		else if (cpu_has_ftlb)
899 			mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
900 		else
901 			mmuextdef = 0;
902 
903 		switch (mmuextdef) {
904 		case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
905 			c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
906 			c->tlbsizevtlb = c->tlbsize;
907 			break;
908 		case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
909 			c->tlbsizevtlb +=
910 				((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
911 				  MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
912 			c->tlbsize = c->tlbsizevtlb;
913 			ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
914 			fallthrough;
915 		case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
916 			if (mips_ftlb_disabled)
917 				break;
918 			newcf4 = (config4 & ~ftlb_page) |
919 				(page_size_ftlb(mmuextdef) <<
920 				 MIPS_CONF4_FTLBPAGESIZE_SHIFT);
921 			write_c0_config4(newcf4);
922 			back_to_back_c0_hazard();
923 			config4 = read_c0_config4();
924 			if (config4 != newcf4) {
925 				pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
926 				       PAGE_SIZE, config4);
927 				/* Switch FTLB off */
928 				set_ftlb_enable(c, 0);
929 				mips_ftlb_disabled = 1;
930 				break;
931 			}
932 			c->tlbsizeftlbsets = 1 <<
933 				((config4 & MIPS_CONF4_FTLBSETS) >>
934 				 MIPS_CONF4_FTLBSETS_SHIFT);
935 			c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
936 					      MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
937 			c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
938 			mips_has_ftlb_configured = 1;
939 			break;
940 		}
941 	}
942 
943 	c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
944 				>> MIPS_CONF4_KSCREXIST_SHIFT;
945 
946 	asid_mask = MIPS_ENTRYHI_ASID;
947 	if (config4 & MIPS_CONF4_AE)
948 		asid_mask |= MIPS_ENTRYHI_ASIDX;
949 	set_cpu_asid_mask(c, asid_mask);
950 
951 	/*
952 	 * Warn if the computed ASID mask doesn't match the mask the kernel
953 	 * is built for. This may indicate either a serious problem or an
954 	 * easy optimisation opportunity, but either way should be addressed.
955 	 */
956 	WARN_ON(asid_mask != cpu_asid_mask(c));
957 
958 	return config4 & MIPS_CONF_M;
959 }
960 
961 static inline unsigned int decode_config5(struct cpuinfo_mips *c)
962 {
963 	unsigned int config5, max_mmid_width;
964 	unsigned long asid_mask;
965 
966 	config5 = read_c0_config5();
967 	config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
968 
969 	if (cpu_has_mips_r6) {
970 		if (!__builtin_constant_p(cpu_has_mmid) || cpu_has_mmid)
971 			config5 |= MIPS_CONF5_MI;
972 		else
973 			config5 &= ~MIPS_CONF5_MI;
974 	}
975 
976 	write_c0_config5(config5);
977 
978 	if (config5 & MIPS_CONF5_EVA)
979 		c->options |= MIPS_CPU_EVA;
980 	if (config5 & MIPS_CONF5_MRP)
981 		c->options |= MIPS_CPU_MAAR;
982 	if (config5 & MIPS_CONF5_LLB)
983 		c->options |= MIPS_CPU_RW_LLB;
984 	if (config5 & MIPS_CONF5_MVH)
985 		c->options |= MIPS_CPU_MVH;
986 	if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
987 		c->options |= MIPS_CPU_VP;
988 	if (config5 & MIPS_CONF5_CA2)
989 		c->ases |= MIPS_ASE_MIPS16E2;
990 
991 	if (config5 & MIPS_CONF5_CRCP)
992 		elf_hwcap |= HWCAP_MIPS_CRC32;
993 
994 	if (cpu_has_mips_r6) {
995 		/* Ensure the write to config5 above takes effect */
996 		back_to_back_c0_hazard();
997 
998 		/* Check whether we successfully enabled MMID support */
999 		config5 = read_c0_config5();
1000 		if (config5 & MIPS_CONF5_MI)
1001 			c->options |= MIPS_CPU_MMID;
1002 
1003 		/*
1004 		 * Warn if we've hardcoded cpu_has_mmid to a value unsuitable
1005 		 * for the CPU we're running on, or if CPUs in an SMP system
1006 		 * have inconsistent MMID support.
1007 		 */
1008 		WARN_ON(!!cpu_has_mmid != !!(config5 & MIPS_CONF5_MI));
1009 
1010 		if (cpu_has_mmid) {
1011 			write_c0_memorymapid(~0ul);
1012 			back_to_back_c0_hazard();
1013 			asid_mask = read_c0_memorymapid();
1014 
1015 			/*
1016 			 * We maintain a bitmap to track MMID allocation, and
1017 			 * need a sensible upper bound on the size of that
1018 			 * bitmap. The initial CPU with MMID support (I6500)
1019 			 * supports 16 bit MMIDs, which gives us an 8KiB
1020 			 * bitmap. The architecture recommends that hardware
1021 			 * support 32 bit MMIDs, which would give us a 512MiB
1022 			 * bitmap - that's too big in most cases.
1023 			 *
1024 			 * Cap MMID width at 16 bits for now & we can revisit
1025 			 * this if & when hardware supports anything wider.
1026 			 */
1027 			max_mmid_width = 16;
1028 			if (asid_mask > GENMASK(max_mmid_width - 1, 0)) {
1029 				pr_info("Capping MMID width at %d bits",
1030 					max_mmid_width);
1031 				asid_mask = GENMASK(max_mmid_width - 1, 0);
1032 			}
1033 
1034 			set_cpu_asid_mask(c, asid_mask);
1035 		}
1036 	}
1037 
1038 	return config5 & MIPS_CONF_M;
1039 }
1040 
1041 static void decode_configs(struct cpuinfo_mips *c)
1042 {
1043 	int ok;
1044 
1045 	/* MIPS32 or MIPS64 compliant CPU.  */
1046 	c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
1047 		     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
1048 
1049 	c->scache.flags = MIPS_CACHE_NOT_PRESENT;
1050 
1051 	/* Enable FTLB if present and not disabled */
1052 	set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
1053 
1054 	ok = decode_config0(c);			/* Read Config registers.  */
1055 	BUG_ON(!ok);				/* Arch spec violation!	 */
1056 	if (ok)
1057 		ok = decode_config1(c);
1058 	if (ok)
1059 		ok = decode_config2(c);
1060 	if (ok)
1061 		ok = decode_config3(c);
1062 	if (ok)
1063 		ok = decode_config4(c);
1064 	if (ok)
1065 		ok = decode_config5(c);
1066 
1067 	/* Probe the EBase.WG bit */
1068 	if (cpu_has_mips_r2_r6) {
1069 		u64 ebase;
1070 		unsigned int status;
1071 
1072 		/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
1073 		ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
1074 					 : (s32)read_c0_ebase();
1075 		if (ebase & MIPS_EBASE_WG) {
1076 			/* WG bit already set, we can avoid the clumsy probe */
1077 			c->options |= MIPS_CPU_EBASE_WG;
1078 		} else {
1079 			/* Its UNDEFINED to change EBase while BEV=0 */
1080 			status = read_c0_status();
1081 			write_c0_status(status | ST0_BEV);
1082 			irq_enable_hazard();
1083 			/*
1084 			 * On pre-r6 cores, this may well clobber the upper bits
1085 			 * of EBase. This is hard to avoid without potentially
1086 			 * hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
1087 			 */
1088 			if (cpu_has_mips64r6)
1089 				write_c0_ebase_64(ebase | MIPS_EBASE_WG);
1090 			else
1091 				write_c0_ebase(ebase | MIPS_EBASE_WG);
1092 			back_to_back_c0_hazard();
1093 			/* Restore BEV */
1094 			write_c0_status(status);
1095 			if (read_c0_ebase() & MIPS_EBASE_WG) {
1096 				c->options |= MIPS_CPU_EBASE_WG;
1097 				write_c0_ebase(ebase);
1098 			}
1099 		}
1100 	}
1101 
1102 	/* configure the FTLB write probability */
1103 	set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
1104 
1105 	mips_probe_watch_registers(c);
1106 
1107 #ifndef CONFIG_MIPS_CPS
1108 	if (cpu_has_mips_r2_r6) {
1109 		unsigned int core;
1110 
1111 		core = get_ebase_cpunum();
1112 		if (cpu_has_mipsmt)
1113 			core >>= fls(core_nvpes()) - 1;
1114 		cpu_set_core(c, core);
1115 	}
1116 #endif
1117 }
1118 
1119 /*
1120  * Probe for certain guest capabilities by writing config bits and reading back.
1121  * Finally write back the original value.
1122  */
1123 #define probe_gc0_config(name, maxconf, bits)				\
1124 do {									\
1125 	unsigned int tmp;						\
1126 	tmp = read_gc0_##name();					\
1127 	write_gc0_##name(tmp | (bits));					\
1128 	back_to_back_c0_hazard();					\
1129 	maxconf = read_gc0_##name();					\
1130 	write_gc0_##name(tmp);						\
1131 } while (0)
1132 
1133 /*
1134  * Probe for dynamic guest capabilities by changing certain config bits and
1135  * reading back to see if they change. Finally write back the original value.
1136  */
1137 #define probe_gc0_config_dyn(name, maxconf, dynconf, bits)		\
1138 do {									\
1139 	maxconf = read_gc0_##name();					\
1140 	write_gc0_##name(maxconf ^ (bits));				\
1141 	back_to_back_c0_hazard();					\
1142 	dynconf = maxconf ^ read_gc0_##name();				\
1143 	write_gc0_##name(maxconf);					\
1144 	maxconf |= dynconf;						\
1145 } while (0)
1146 
1147 static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
1148 {
1149 	unsigned int config0;
1150 
1151 	probe_gc0_config(config, config0, MIPS_CONF_M);
1152 
1153 	if (config0 & MIPS_CONF_M)
1154 		c->guest.conf |= BIT(1);
1155 	return config0 & MIPS_CONF_M;
1156 }
1157 
1158 static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
1159 {
1160 	unsigned int config1, config1_dyn;
1161 
1162 	probe_gc0_config_dyn(config1, config1, config1_dyn,
1163 			     MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
1164 			     MIPS_CONF1_FP);
1165 
1166 	if (config1 & MIPS_CONF1_FP)
1167 		c->guest.options |= MIPS_CPU_FPU;
1168 	if (config1_dyn & MIPS_CONF1_FP)
1169 		c->guest.options_dyn |= MIPS_CPU_FPU;
1170 
1171 	if (config1 & MIPS_CONF1_WR)
1172 		c->guest.options |= MIPS_CPU_WATCH;
1173 	if (config1_dyn & MIPS_CONF1_WR)
1174 		c->guest.options_dyn |= MIPS_CPU_WATCH;
1175 
1176 	if (config1 & MIPS_CONF1_PC)
1177 		c->guest.options |= MIPS_CPU_PERF;
1178 	if (config1_dyn & MIPS_CONF1_PC)
1179 		c->guest.options_dyn |= MIPS_CPU_PERF;
1180 
1181 	if (config1 & MIPS_CONF_M)
1182 		c->guest.conf |= BIT(2);
1183 	return config1 & MIPS_CONF_M;
1184 }
1185 
1186 static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
1187 {
1188 	unsigned int config2;
1189 
1190 	probe_gc0_config(config2, config2, MIPS_CONF_M);
1191 
1192 	if (config2 & MIPS_CONF_M)
1193 		c->guest.conf |= BIT(3);
1194 	return config2 & MIPS_CONF_M;
1195 }
1196 
1197 static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
1198 {
1199 	unsigned int config3, config3_dyn;
1200 
1201 	probe_gc0_config_dyn(config3, config3, config3_dyn,
1202 			     MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
1203 			     MIPS_CONF3_CTXTC);
1204 
1205 	if (config3 & MIPS_CONF3_CTXTC)
1206 		c->guest.options |= MIPS_CPU_CTXTC;
1207 	if (config3_dyn & MIPS_CONF3_CTXTC)
1208 		c->guest.options_dyn |= MIPS_CPU_CTXTC;
1209 
1210 	if (config3 & MIPS_CONF3_PW)
1211 		c->guest.options |= MIPS_CPU_HTW;
1212 
1213 	if (config3 & MIPS_CONF3_ULRI)
1214 		c->guest.options |= MIPS_CPU_ULRI;
1215 
1216 	if (config3 & MIPS_CONF3_SC)
1217 		c->guest.options |= MIPS_CPU_SEGMENTS;
1218 
1219 	if (config3 & MIPS_CONF3_BI)
1220 		c->guest.options |= MIPS_CPU_BADINSTR;
1221 	if (config3 & MIPS_CONF3_BP)
1222 		c->guest.options |= MIPS_CPU_BADINSTRP;
1223 
1224 	if (config3 & MIPS_CONF3_MSA)
1225 		c->guest.ases |= MIPS_ASE_MSA;
1226 	if (config3_dyn & MIPS_CONF3_MSA)
1227 		c->guest.ases_dyn |= MIPS_ASE_MSA;
1228 
1229 	if (config3 & MIPS_CONF_M)
1230 		c->guest.conf |= BIT(4);
1231 	return config3 & MIPS_CONF_M;
1232 }
1233 
1234 static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
1235 {
1236 	unsigned int config4;
1237 
1238 	probe_gc0_config(config4, config4,
1239 			 MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
1240 
1241 	c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
1242 				>> MIPS_CONF4_KSCREXIST_SHIFT;
1243 
1244 	if (config4 & MIPS_CONF_M)
1245 		c->guest.conf |= BIT(5);
1246 	return config4 & MIPS_CONF_M;
1247 }
1248 
1249 static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
1250 {
1251 	unsigned int config5, config5_dyn;
1252 
1253 	probe_gc0_config_dyn(config5, config5, config5_dyn,
1254 			 MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
1255 
1256 	if (config5 & MIPS_CONF5_MRP)
1257 		c->guest.options |= MIPS_CPU_MAAR;
1258 	if (config5_dyn & MIPS_CONF5_MRP)
1259 		c->guest.options_dyn |= MIPS_CPU_MAAR;
1260 
1261 	if (config5 & MIPS_CONF5_LLB)
1262 		c->guest.options |= MIPS_CPU_RW_LLB;
1263 
1264 	if (config5 & MIPS_CONF5_MVH)
1265 		c->guest.options |= MIPS_CPU_MVH;
1266 
1267 	if (config5 & MIPS_CONF_M)
1268 		c->guest.conf |= BIT(6);
1269 	return config5 & MIPS_CONF_M;
1270 }
1271 
1272 static inline void decode_guest_configs(struct cpuinfo_mips *c)
1273 {
1274 	unsigned int ok;
1275 
1276 	ok = decode_guest_config0(c);
1277 	if (ok)
1278 		ok = decode_guest_config1(c);
1279 	if (ok)
1280 		ok = decode_guest_config2(c);
1281 	if (ok)
1282 		ok = decode_guest_config3(c);
1283 	if (ok)
1284 		ok = decode_guest_config4(c);
1285 	if (ok)
1286 		decode_guest_config5(c);
1287 }
1288 
1289 static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
1290 {
1291 	unsigned int guestctl0, temp;
1292 
1293 	guestctl0 = read_c0_guestctl0();
1294 
1295 	if (guestctl0 & MIPS_GCTL0_G0E)
1296 		c->options |= MIPS_CPU_GUESTCTL0EXT;
1297 	if (guestctl0 & MIPS_GCTL0_G1)
1298 		c->options |= MIPS_CPU_GUESTCTL1;
1299 	if (guestctl0 & MIPS_GCTL0_G2)
1300 		c->options |= MIPS_CPU_GUESTCTL2;
1301 	if (!(guestctl0 & MIPS_GCTL0_RAD)) {
1302 		c->options |= MIPS_CPU_GUESTID;
1303 
1304 		/*
1305 		 * Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
1306 		 * first, otherwise all data accesses will be fully virtualised
1307 		 * as if they were performed by guest mode.
1308 		 */
1309 		write_c0_guestctl1(0);
1310 		tlbw_use_hazard();
1311 
1312 		write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
1313 		back_to_back_c0_hazard();
1314 		temp = read_c0_guestctl0();
1315 
1316 		if (temp & MIPS_GCTL0_DRG) {
1317 			write_c0_guestctl0(guestctl0);
1318 			c->options |= MIPS_CPU_DRG;
1319 		}
1320 	}
1321 }
1322 
1323 static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
1324 {
1325 	if (cpu_has_guestid) {
1326 		/* determine the number of bits of GuestID available */
1327 		write_c0_guestctl1(MIPS_GCTL1_ID);
1328 		back_to_back_c0_hazard();
1329 		c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
1330 						>> MIPS_GCTL1_ID_SHIFT;
1331 		write_c0_guestctl1(0);
1332 	}
1333 }
1334 
1335 static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
1336 {
1337 	/* determine the number of bits of GTOffset available */
1338 	write_c0_gtoffset(0xffffffff);
1339 	back_to_back_c0_hazard();
1340 	c->gtoffset_mask = read_c0_gtoffset();
1341 	write_c0_gtoffset(0);
1342 }
1343 
1344 static inline void cpu_probe_vz(struct cpuinfo_mips *c)
1345 {
1346 	cpu_probe_guestctl0(c);
1347 	if (cpu_has_guestctl1)
1348 		cpu_probe_guestctl1(c);
1349 
1350 	cpu_probe_gtoffset(c);
1351 
1352 	decode_guest_configs(c);
1353 }
1354 
1355 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
1356 		| MIPS_CPU_COUNTER)
1357 
1358 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
1359 {
1360 	switch (c->processor_id & PRID_IMP_MASK) {
1361 	case PRID_IMP_R2000:
1362 		c->cputype = CPU_R2000;
1363 		__cpu_name[cpu] = "R2000";
1364 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1365 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1366 			     MIPS_CPU_NOFPUEX;
1367 		if (__cpu_has_fpu())
1368 			c->options |= MIPS_CPU_FPU;
1369 		c->tlbsize = 64;
1370 		break;
1371 	case PRID_IMP_R3000:
1372 		if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
1373 			if (cpu_has_confreg()) {
1374 				c->cputype = CPU_R3081E;
1375 				__cpu_name[cpu] = "R3081";
1376 			} else {
1377 				c->cputype = CPU_R3000A;
1378 				__cpu_name[cpu] = "R3000A";
1379 			}
1380 		} else {
1381 			c->cputype = CPU_R3000;
1382 			__cpu_name[cpu] = "R3000";
1383 		}
1384 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1385 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
1386 			     MIPS_CPU_NOFPUEX;
1387 		if (__cpu_has_fpu())
1388 			c->options |= MIPS_CPU_FPU;
1389 		c->tlbsize = 64;
1390 		break;
1391 	case PRID_IMP_R4000:
1392 		if (read_c0_config() & CONF_SC) {
1393 			if ((c->processor_id & PRID_REV_MASK) >=
1394 			    PRID_REV_R4400) {
1395 				c->cputype = CPU_R4400PC;
1396 				__cpu_name[cpu] = "R4400PC";
1397 			} else {
1398 				c->cputype = CPU_R4000PC;
1399 				__cpu_name[cpu] = "R4000PC";
1400 			}
1401 		} else {
1402 			int cca = read_c0_config() & CONF_CM_CMASK;
1403 			int mc;
1404 
1405 			/*
1406 			 * SC and MC versions can't be reliably told apart,
1407 			 * but only the latter support coherent caching
1408 			 * modes so assume the firmware has set the KSEG0
1409 			 * coherency attribute reasonably (if uncached, we
1410 			 * assume SC).
1411 			 */
1412 			switch (cca) {
1413 			case CONF_CM_CACHABLE_CE:
1414 			case CONF_CM_CACHABLE_COW:
1415 			case CONF_CM_CACHABLE_CUW:
1416 				mc = 1;
1417 				break;
1418 			default:
1419 				mc = 0;
1420 				break;
1421 			}
1422 			if ((c->processor_id & PRID_REV_MASK) >=
1423 			    PRID_REV_R4400) {
1424 				c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
1425 				__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
1426 			} else {
1427 				c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
1428 				__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
1429 			}
1430 		}
1431 
1432 		set_isa(c, MIPS_CPU_ISA_III);
1433 		c->fpu_msk31 |= FPU_CSR_CONDX;
1434 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1435 			     MIPS_CPU_WATCH | MIPS_CPU_VCE |
1436 			     MIPS_CPU_LLSC;
1437 		c->tlbsize = 48;
1438 		break;
1439 	case PRID_IMP_VR41XX:
1440 		set_isa(c, MIPS_CPU_ISA_III);
1441 		c->fpu_msk31 |= FPU_CSR_CONDX;
1442 		c->options = R4K_OPTS;
1443 		c->tlbsize = 32;
1444 		switch (c->processor_id & 0xf0) {
1445 		case PRID_REV_VR4111:
1446 			c->cputype = CPU_VR4111;
1447 			__cpu_name[cpu] = "NEC VR4111";
1448 			break;
1449 		case PRID_REV_VR4121:
1450 			c->cputype = CPU_VR4121;
1451 			__cpu_name[cpu] = "NEC VR4121";
1452 			break;
1453 		case PRID_REV_VR4122:
1454 			if ((c->processor_id & 0xf) < 0x3) {
1455 				c->cputype = CPU_VR4122;
1456 				__cpu_name[cpu] = "NEC VR4122";
1457 			} else {
1458 				c->cputype = CPU_VR4181A;
1459 				__cpu_name[cpu] = "NEC VR4181A";
1460 			}
1461 			break;
1462 		case PRID_REV_VR4130:
1463 			if ((c->processor_id & 0xf) < 0x4) {
1464 				c->cputype = CPU_VR4131;
1465 				__cpu_name[cpu] = "NEC VR4131";
1466 			} else {
1467 				c->cputype = CPU_VR4133;
1468 				c->options |= MIPS_CPU_LLSC;
1469 				__cpu_name[cpu] = "NEC VR4133";
1470 			}
1471 			break;
1472 		default:
1473 			printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
1474 			c->cputype = CPU_VR41XX;
1475 			__cpu_name[cpu] = "NEC Vr41xx";
1476 			break;
1477 		}
1478 		break;
1479 	case PRID_IMP_R4600:
1480 		c->cputype = CPU_R4600;
1481 		__cpu_name[cpu] = "R4600";
1482 		set_isa(c, MIPS_CPU_ISA_III);
1483 		c->fpu_msk31 |= FPU_CSR_CONDX;
1484 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1485 			     MIPS_CPU_LLSC;
1486 		c->tlbsize = 48;
1487 		break;
1488 	#if 0
1489 	case PRID_IMP_R4650:
1490 		/*
1491 		 * This processor doesn't have an MMU, so it's not
1492 		 * "real easy" to run Linux on it. It is left purely
1493 		 * for documentation.  Commented out because it shares
1494 		 * it's c0_prid id number with the TX3900.
1495 		 */
1496 		c->cputype = CPU_R4650;
1497 		__cpu_name[cpu] = "R4650";
1498 		set_isa(c, MIPS_CPU_ISA_III);
1499 		c->fpu_msk31 |= FPU_CSR_CONDX;
1500 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
1501 		c->tlbsize = 48;
1502 		break;
1503 	#endif
1504 	case PRID_IMP_TX39:
1505 		c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
1506 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
1507 
1508 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
1509 			c->cputype = CPU_TX3927;
1510 			__cpu_name[cpu] = "TX3927";
1511 			c->tlbsize = 64;
1512 		} else {
1513 			switch (c->processor_id & PRID_REV_MASK) {
1514 			case PRID_REV_TX3912:
1515 				c->cputype = CPU_TX3912;
1516 				__cpu_name[cpu] = "TX3912";
1517 				c->tlbsize = 32;
1518 				break;
1519 			case PRID_REV_TX3922:
1520 				c->cputype = CPU_TX3922;
1521 				__cpu_name[cpu] = "TX3922";
1522 				c->tlbsize = 64;
1523 				break;
1524 			}
1525 		}
1526 		break;
1527 	case PRID_IMP_R4700:
1528 		c->cputype = CPU_R4700;
1529 		__cpu_name[cpu] = "R4700";
1530 		set_isa(c, MIPS_CPU_ISA_III);
1531 		c->fpu_msk31 |= FPU_CSR_CONDX;
1532 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1533 			     MIPS_CPU_LLSC;
1534 		c->tlbsize = 48;
1535 		break;
1536 	case PRID_IMP_TX49:
1537 		c->cputype = CPU_TX49XX;
1538 		__cpu_name[cpu] = "R49XX";
1539 		set_isa(c, MIPS_CPU_ISA_III);
1540 		c->fpu_msk31 |= FPU_CSR_CONDX;
1541 		c->options = R4K_OPTS | MIPS_CPU_LLSC;
1542 		if (!(c->processor_id & 0x08))
1543 			c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
1544 		c->tlbsize = 48;
1545 		break;
1546 	case PRID_IMP_R5000:
1547 		c->cputype = CPU_R5000;
1548 		__cpu_name[cpu] = "R5000";
1549 		set_isa(c, MIPS_CPU_ISA_IV);
1550 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1551 			     MIPS_CPU_LLSC;
1552 		c->tlbsize = 48;
1553 		break;
1554 	case PRID_IMP_R5500:
1555 		c->cputype = CPU_R5500;
1556 		__cpu_name[cpu] = "R5500";
1557 		set_isa(c, MIPS_CPU_ISA_IV);
1558 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1559 			     MIPS_CPU_WATCH | MIPS_CPU_LLSC;
1560 		c->tlbsize = 48;
1561 		break;
1562 	case PRID_IMP_NEVADA:
1563 		c->cputype = CPU_NEVADA;
1564 		__cpu_name[cpu] = "Nevada";
1565 		set_isa(c, MIPS_CPU_ISA_IV);
1566 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1567 			     MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
1568 		c->tlbsize = 48;
1569 		break;
1570 	case PRID_IMP_RM7000:
1571 		c->cputype = CPU_RM7000;
1572 		__cpu_name[cpu] = "RM7000";
1573 		set_isa(c, MIPS_CPU_ISA_IV);
1574 		c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
1575 			     MIPS_CPU_LLSC;
1576 		/*
1577 		 * Undocumented RM7000:	 Bit 29 in the info register of
1578 		 * the RM7000 v2.0 indicates if the TLB has 48 or 64
1579 		 * entries.
1580 		 *
1581 		 * 29	   1 =>	   64 entry JTLB
1582 		 *	   0 =>	   48 entry JTLB
1583 		 */
1584 		c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
1585 		break;
1586 	case PRID_IMP_R10000:
1587 		c->cputype = CPU_R10000;
1588 		__cpu_name[cpu] = "R10000";
1589 		set_isa(c, MIPS_CPU_ISA_IV);
1590 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1591 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1592 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1593 			     MIPS_CPU_LLSC;
1594 		c->tlbsize = 64;
1595 		break;
1596 	case PRID_IMP_R12000:
1597 		c->cputype = CPU_R12000;
1598 		__cpu_name[cpu] = "R12000";
1599 		set_isa(c, MIPS_CPU_ISA_IV);
1600 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1601 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1602 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1603 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1604 		c->tlbsize = 64;
1605 		break;
1606 	case PRID_IMP_R14000:
1607 		if (((c->processor_id >> 4) & 0x0f) > 2) {
1608 			c->cputype = CPU_R16000;
1609 			__cpu_name[cpu] = "R16000";
1610 		} else {
1611 			c->cputype = CPU_R14000;
1612 			__cpu_name[cpu] = "R14000";
1613 		}
1614 		set_isa(c, MIPS_CPU_ISA_IV);
1615 		c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
1616 			     MIPS_CPU_FPU | MIPS_CPU_32FPR |
1617 			     MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
1618 			     MIPS_CPU_LLSC | MIPS_CPU_BP_GHIST;
1619 		c->tlbsize = 64;
1620 		break;
1621 	case PRID_IMP_LOONGSON_64C:  /* Loongson-2/3 */
1622 		switch (c->processor_id & PRID_REV_MASK) {
1623 		case PRID_REV_LOONGSON2E:
1624 			c->cputype = CPU_LOONGSON2EF;
1625 			__cpu_name[cpu] = "ICT Loongson-2";
1626 			set_elf_platform(cpu, "loongson2e");
1627 			set_isa(c, MIPS_CPU_ISA_III);
1628 			c->fpu_msk31 |= FPU_CSR_CONDX;
1629 			break;
1630 		case PRID_REV_LOONGSON2F:
1631 			c->cputype = CPU_LOONGSON2EF;
1632 			__cpu_name[cpu] = "ICT Loongson-2";
1633 			set_elf_platform(cpu, "loongson2f");
1634 			set_isa(c, MIPS_CPU_ISA_III);
1635 			c->fpu_msk31 |= FPU_CSR_CONDX;
1636 			break;
1637 		case PRID_REV_LOONGSON3A_R1:
1638 			c->cputype = CPU_LOONGSON64;
1639 			__cpu_name[cpu] = "ICT Loongson-3";
1640 			set_elf_platform(cpu, "loongson3a");
1641 			set_isa(c, MIPS_CPU_ISA_M64R1);
1642 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1643 				MIPS_ASE_LOONGSON_EXT);
1644 			break;
1645 		case PRID_REV_LOONGSON3B_R1:
1646 		case PRID_REV_LOONGSON3B_R2:
1647 			c->cputype = CPU_LOONGSON64;
1648 			__cpu_name[cpu] = "ICT Loongson-3";
1649 			set_elf_platform(cpu, "loongson3b");
1650 			set_isa(c, MIPS_CPU_ISA_M64R1);
1651 			c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
1652 				MIPS_ASE_LOONGSON_EXT);
1653 			break;
1654 		}
1655 
1656 		c->options = R4K_OPTS |
1657 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |
1658 			     MIPS_CPU_32FPR;
1659 		c->tlbsize = 64;
1660 		set_cpu_asid_mask(c, MIPS_ENTRYHI_ASID);
1661 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1662 		break;
1663 	case PRID_IMP_LOONGSON_32:  /* Loongson-1 */
1664 		decode_configs(c);
1665 
1666 		c->cputype = CPU_LOONGSON32;
1667 
1668 		switch (c->processor_id & PRID_REV_MASK) {
1669 		case PRID_REV_LOONGSON1B:
1670 			__cpu_name[cpu] = "Loongson 1B";
1671 			break;
1672 		}
1673 
1674 		break;
1675 	}
1676 }
1677 
1678 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
1679 {
1680 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1681 	switch (c->processor_id & PRID_IMP_MASK) {
1682 	case PRID_IMP_QEMU_GENERIC:
1683 		c->writecombine = _CACHE_UNCACHED;
1684 		c->cputype = CPU_QEMU_GENERIC;
1685 		__cpu_name[cpu] = "MIPS GENERIC QEMU";
1686 		break;
1687 	case PRID_IMP_4KC:
1688 		c->cputype = CPU_4KC;
1689 		c->writecombine = _CACHE_UNCACHED;
1690 		__cpu_name[cpu] = "MIPS 4Kc";
1691 		break;
1692 	case PRID_IMP_4KEC:
1693 	case PRID_IMP_4KECR2:
1694 		c->cputype = CPU_4KEC;
1695 		c->writecombine = _CACHE_UNCACHED;
1696 		__cpu_name[cpu] = "MIPS 4KEc";
1697 		break;
1698 	case PRID_IMP_4KSC:
1699 	case PRID_IMP_4KSD:
1700 		c->cputype = CPU_4KSC;
1701 		c->writecombine = _CACHE_UNCACHED;
1702 		__cpu_name[cpu] = "MIPS 4KSc";
1703 		break;
1704 	case PRID_IMP_5KC:
1705 		c->cputype = CPU_5KC;
1706 		c->writecombine = _CACHE_UNCACHED;
1707 		__cpu_name[cpu] = "MIPS 5Kc";
1708 		break;
1709 	case PRID_IMP_5KE:
1710 		c->cputype = CPU_5KE;
1711 		c->writecombine = _CACHE_UNCACHED;
1712 		__cpu_name[cpu] = "MIPS 5KE";
1713 		break;
1714 	case PRID_IMP_20KC:
1715 		c->cputype = CPU_20KC;
1716 		c->writecombine = _CACHE_UNCACHED;
1717 		__cpu_name[cpu] = "MIPS 20Kc";
1718 		break;
1719 	case PRID_IMP_24K:
1720 		c->cputype = CPU_24K;
1721 		c->writecombine = _CACHE_UNCACHED;
1722 		__cpu_name[cpu] = "MIPS 24Kc";
1723 		break;
1724 	case PRID_IMP_24KE:
1725 		c->cputype = CPU_24K;
1726 		c->writecombine = _CACHE_UNCACHED;
1727 		__cpu_name[cpu] = "MIPS 24KEc";
1728 		break;
1729 	case PRID_IMP_25KF:
1730 		c->cputype = CPU_25KF;
1731 		c->writecombine = _CACHE_UNCACHED;
1732 		__cpu_name[cpu] = "MIPS 25Kc";
1733 		break;
1734 	case PRID_IMP_34K:
1735 		c->cputype = CPU_34K;
1736 		c->writecombine = _CACHE_UNCACHED;
1737 		__cpu_name[cpu] = "MIPS 34Kc";
1738 		cpu_set_mt_per_tc_perf(c);
1739 		break;
1740 	case PRID_IMP_74K:
1741 		c->cputype = CPU_74K;
1742 		c->writecombine = _CACHE_UNCACHED;
1743 		__cpu_name[cpu] = "MIPS 74Kc";
1744 		break;
1745 	case PRID_IMP_M14KC:
1746 		c->cputype = CPU_M14KC;
1747 		c->writecombine = _CACHE_UNCACHED;
1748 		__cpu_name[cpu] = "MIPS M14Kc";
1749 		break;
1750 	case PRID_IMP_M14KEC:
1751 		c->cputype = CPU_M14KEC;
1752 		c->writecombine = _CACHE_UNCACHED;
1753 		__cpu_name[cpu] = "MIPS M14KEc";
1754 		break;
1755 	case PRID_IMP_1004K:
1756 		c->cputype = CPU_1004K;
1757 		c->writecombine = _CACHE_UNCACHED;
1758 		__cpu_name[cpu] = "MIPS 1004Kc";
1759 		cpu_set_mt_per_tc_perf(c);
1760 		break;
1761 	case PRID_IMP_1074K:
1762 		c->cputype = CPU_1074K;
1763 		c->writecombine = _CACHE_UNCACHED;
1764 		__cpu_name[cpu] = "MIPS 1074Kc";
1765 		break;
1766 	case PRID_IMP_INTERAPTIV_UP:
1767 		c->cputype = CPU_INTERAPTIV;
1768 		__cpu_name[cpu] = "MIPS interAptiv";
1769 		cpu_set_mt_per_tc_perf(c);
1770 		break;
1771 	case PRID_IMP_INTERAPTIV_MP:
1772 		c->cputype = CPU_INTERAPTIV;
1773 		__cpu_name[cpu] = "MIPS interAptiv (multi)";
1774 		cpu_set_mt_per_tc_perf(c);
1775 		break;
1776 	case PRID_IMP_PROAPTIV_UP:
1777 		c->cputype = CPU_PROAPTIV;
1778 		__cpu_name[cpu] = "MIPS proAptiv";
1779 		break;
1780 	case PRID_IMP_PROAPTIV_MP:
1781 		c->cputype = CPU_PROAPTIV;
1782 		__cpu_name[cpu] = "MIPS proAptiv (multi)";
1783 		break;
1784 	case PRID_IMP_P5600:
1785 		c->cputype = CPU_P5600;
1786 		__cpu_name[cpu] = "MIPS P5600";
1787 		break;
1788 	case PRID_IMP_P6600:
1789 		c->cputype = CPU_P6600;
1790 		__cpu_name[cpu] = "MIPS P6600";
1791 		break;
1792 	case PRID_IMP_I6400:
1793 		c->cputype = CPU_I6400;
1794 		__cpu_name[cpu] = "MIPS I6400";
1795 		break;
1796 	case PRID_IMP_I6500:
1797 		c->cputype = CPU_I6500;
1798 		__cpu_name[cpu] = "MIPS I6500";
1799 		break;
1800 	case PRID_IMP_M5150:
1801 		c->cputype = CPU_M5150;
1802 		__cpu_name[cpu] = "MIPS M5150";
1803 		break;
1804 	case PRID_IMP_M6250:
1805 		c->cputype = CPU_M6250;
1806 		__cpu_name[cpu] = "MIPS M6250";
1807 		break;
1808 	}
1809 
1810 	decode_configs(c);
1811 
1812 	spram_config();
1813 
1814 	mm_config(c);
1815 
1816 	switch (__get_cpu_type(c->cputype)) {
1817 	case CPU_M5150:
1818 	case CPU_P5600:
1819 		set_isa(c, MIPS_CPU_ISA_M32R5);
1820 		break;
1821 	case CPU_I6500:
1822 		c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
1823 		fallthrough;
1824 	case CPU_I6400:
1825 		c->options |= MIPS_CPU_SHARED_FTLB_RAM;
1826 		fallthrough;
1827 	default:
1828 		break;
1829 	}
1830 }
1831 
1832 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
1833 {
1834 	decode_configs(c);
1835 	switch (c->processor_id & PRID_IMP_MASK) {
1836 	case PRID_IMP_AU1_REV1:
1837 	case PRID_IMP_AU1_REV2:
1838 		c->cputype = CPU_ALCHEMY;
1839 		switch ((c->processor_id >> 24) & 0xff) {
1840 		case 0:
1841 			__cpu_name[cpu] = "Au1000";
1842 			break;
1843 		case 1:
1844 			__cpu_name[cpu] = "Au1500";
1845 			break;
1846 		case 2:
1847 			__cpu_name[cpu] = "Au1100";
1848 			break;
1849 		case 3:
1850 			__cpu_name[cpu] = "Au1550";
1851 			break;
1852 		case 4:
1853 			__cpu_name[cpu] = "Au1200";
1854 			if ((c->processor_id & PRID_REV_MASK) == 2)
1855 				__cpu_name[cpu] = "Au1250";
1856 			break;
1857 		case 5:
1858 			__cpu_name[cpu] = "Au1210";
1859 			break;
1860 		default:
1861 			__cpu_name[cpu] = "Au1xxx";
1862 			break;
1863 		}
1864 		break;
1865 	}
1866 }
1867 
1868 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
1869 {
1870 	decode_configs(c);
1871 
1872 	c->writecombine = _CACHE_UNCACHED_ACCELERATED;
1873 	switch (c->processor_id & PRID_IMP_MASK) {
1874 	case PRID_IMP_SB1:
1875 		c->cputype = CPU_SB1;
1876 		__cpu_name[cpu] = "SiByte SB1";
1877 		/* FPU in pass1 is known to have issues. */
1878 		if ((c->processor_id & PRID_REV_MASK) < 0x02)
1879 			c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
1880 		break;
1881 	case PRID_IMP_SB1A:
1882 		c->cputype = CPU_SB1A;
1883 		__cpu_name[cpu] = "SiByte SB1A";
1884 		break;
1885 	}
1886 }
1887 
1888 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
1889 {
1890 	decode_configs(c);
1891 	switch (c->processor_id & PRID_IMP_MASK) {
1892 	case PRID_IMP_SR71000:
1893 		c->cputype = CPU_SR71000;
1894 		__cpu_name[cpu] = "Sandcraft SR71000";
1895 		c->scache.ways = 8;
1896 		c->tlbsize = 64;
1897 		break;
1898 	}
1899 }
1900 
1901 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
1902 {
1903 	decode_configs(c);
1904 	switch (c->processor_id & PRID_IMP_MASK) {
1905 	case PRID_IMP_PR4450:
1906 		c->cputype = CPU_PR4450;
1907 		__cpu_name[cpu] = "Philips PR4450";
1908 		set_isa(c, MIPS_CPU_ISA_M32R1);
1909 		break;
1910 	}
1911 }
1912 
1913 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
1914 {
1915 	decode_configs(c);
1916 	switch (c->processor_id & PRID_IMP_MASK) {
1917 	case PRID_IMP_BMIPS32_REV4:
1918 	case PRID_IMP_BMIPS32_REV8:
1919 		c->cputype = CPU_BMIPS32;
1920 		__cpu_name[cpu] = "Broadcom BMIPS32";
1921 		set_elf_platform(cpu, "bmips32");
1922 		break;
1923 	case PRID_IMP_BMIPS3300:
1924 	case PRID_IMP_BMIPS3300_ALT:
1925 	case PRID_IMP_BMIPS3300_BUG:
1926 		c->cputype = CPU_BMIPS3300;
1927 		__cpu_name[cpu] = "Broadcom BMIPS3300";
1928 		set_elf_platform(cpu, "bmips3300");
1929 		break;
1930 	case PRID_IMP_BMIPS43XX: {
1931 		int rev = c->processor_id & PRID_REV_MASK;
1932 
1933 		if (rev >= PRID_REV_BMIPS4380_LO &&
1934 				rev <= PRID_REV_BMIPS4380_HI) {
1935 			c->cputype = CPU_BMIPS4380;
1936 			__cpu_name[cpu] = "Broadcom BMIPS4380";
1937 			set_elf_platform(cpu, "bmips4380");
1938 			c->options |= MIPS_CPU_RIXI;
1939 		} else {
1940 			c->cputype = CPU_BMIPS4350;
1941 			__cpu_name[cpu] = "Broadcom BMIPS4350";
1942 			set_elf_platform(cpu, "bmips4350");
1943 		}
1944 		break;
1945 	}
1946 	case PRID_IMP_BMIPS5000:
1947 	case PRID_IMP_BMIPS5200:
1948 		c->cputype = CPU_BMIPS5000;
1949 		if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
1950 			__cpu_name[cpu] = "Broadcom BMIPS5200";
1951 		else
1952 			__cpu_name[cpu] = "Broadcom BMIPS5000";
1953 		set_elf_platform(cpu, "bmips5000");
1954 		c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
1955 		break;
1956 	}
1957 }
1958 
1959 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
1960 {
1961 	decode_configs(c);
1962 	switch (c->processor_id & PRID_IMP_MASK) {
1963 	case PRID_IMP_CAVIUM_CN38XX:
1964 	case PRID_IMP_CAVIUM_CN31XX:
1965 	case PRID_IMP_CAVIUM_CN30XX:
1966 		c->cputype = CPU_CAVIUM_OCTEON;
1967 		__cpu_name[cpu] = "Cavium Octeon";
1968 		goto platform;
1969 	case PRID_IMP_CAVIUM_CN58XX:
1970 	case PRID_IMP_CAVIUM_CN56XX:
1971 	case PRID_IMP_CAVIUM_CN50XX:
1972 	case PRID_IMP_CAVIUM_CN52XX:
1973 		c->cputype = CPU_CAVIUM_OCTEON_PLUS;
1974 		__cpu_name[cpu] = "Cavium Octeon+";
1975 platform:
1976 		set_elf_platform(cpu, "octeon");
1977 		break;
1978 	case PRID_IMP_CAVIUM_CN61XX:
1979 	case PRID_IMP_CAVIUM_CN63XX:
1980 	case PRID_IMP_CAVIUM_CN66XX:
1981 	case PRID_IMP_CAVIUM_CN68XX:
1982 	case PRID_IMP_CAVIUM_CNF71XX:
1983 		c->cputype = CPU_CAVIUM_OCTEON2;
1984 		__cpu_name[cpu] = "Cavium Octeon II";
1985 		set_elf_platform(cpu, "octeon2");
1986 		break;
1987 	case PRID_IMP_CAVIUM_CN70XX:
1988 	case PRID_IMP_CAVIUM_CN73XX:
1989 	case PRID_IMP_CAVIUM_CNF75XX:
1990 	case PRID_IMP_CAVIUM_CN78XX:
1991 		c->cputype = CPU_CAVIUM_OCTEON3;
1992 		__cpu_name[cpu] = "Cavium Octeon III";
1993 		set_elf_platform(cpu, "octeon3");
1994 		break;
1995 	default:
1996 		printk(KERN_INFO "Unknown Octeon chip!\n");
1997 		c->cputype = CPU_UNKNOWN;
1998 		break;
1999 	}
2000 }
2001 
2002 #ifdef CONFIG_CPU_LOONGSON64
2003 #include <loongson_regs.h>
2004 
2005 static inline void decode_cpucfg(struct cpuinfo_mips *c)
2006 {
2007 	u32 cfg1 = read_cpucfg(LOONGSON_CFG1);
2008 	u32 cfg2 = read_cpucfg(LOONGSON_CFG2);
2009 	u32 cfg3 = read_cpucfg(LOONGSON_CFG3);
2010 
2011 	if (cfg1 & LOONGSON_CFG1_MMI)
2012 		c->ases |= MIPS_ASE_LOONGSON_MMI;
2013 
2014 	if (cfg2 & LOONGSON_CFG2_LEXT1)
2015 		c->ases |= MIPS_ASE_LOONGSON_EXT;
2016 
2017 	if (cfg2 & LOONGSON_CFG2_LEXT2)
2018 		c->ases |= MIPS_ASE_LOONGSON_EXT2;
2019 
2020 	if (cfg2 & LOONGSON_CFG2_LSPW) {
2021 		c->options |= MIPS_CPU_LDPTE;
2022 		c->guest.options |= MIPS_CPU_LDPTE;
2023 	}
2024 
2025 	if (cfg3 & LOONGSON_CFG3_LCAMP)
2026 		c->ases |= MIPS_ASE_LOONGSON_CAM;
2027 }
2028 
2029 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
2030 {
2031 	decode_configs(c);
2032 
2033 	switch (c->processor_id & PRID_IMP_MASK) {
2034 	case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */
2035 		switch (c->processor_id & PRID_REV_MASK) {
2036 		case PRID_REV_LOONGSON2K_R1_0:
2037 		case PRID_REV_LOONGSON2K_R1_1:
2038 		case PRID_REV_LOONGSON2K_R1_2:
2039 		case PRID_REV_LOONGSON2K_R1_3:
2040 			c->cputype = CPU_LOONGSON64;
2041 			__cpu_name[cpu] = "Loongson-2K";
2042 			set_elf_platform(cpu, "gs264e");
2043 			set_isa(c, MIPS_CPU_ISA_M64R2);
2044 			break;
2045 		}
2046 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
2047 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT |
2048 				MIPS_ASE_LOONGSON_EXT2);
2049 		break;
2050 	case PRID_IMP_LOONGSON_64C:  /* Loongson-3 Classic */
2051 		switch (c->processor_id & PRID_REV_MASK) {
2052 		case PRID_REV_LOONGSON3A_R2_0:
2053 		case PRID_REV_LOONGSON3A_R2_1:
2054 			c->cputype = CPU_LOONGSON64;
2055 			__cpu_name[cpu] = "ICT Loongson-3";
2056 			set_elf_platform(cpu, "loongson3a");
2057 			set_isa(c, MIPS_CPU_ISA_M64R2);
2058 			break;
2059 		case PRID_REV_LOONGSON3A_R3_0:
2060 		case PRID_REV_LOONGSON3A_R3_1:
2061 			c->cputype = CPU_LOONGSON64;
2062 			__cpu_name[cpu] = "ICT Loongson-3";
2063 			set_elf_platform(cpu, "loongson3a");
2064 			set_isa(c, MIPS_CPU_ISA_M64R2);
2065 			break;
2066 		}
2067 		/*
2068 		 * Loongson-3 Classic did not implement MIPS standard TLBINV
2069 		 * but implemented TLBINVF and EHINV. As currently we're only
2070 		 * using these two features, enable MIPS_CPU_TLBINV as well.
2071 		 *
2072 		 * Also some early Loongson-3A2000 had wrong TLB type in Config
2073 		 * register, we correct it here.
2074 		 */
2075 		c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
2076 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
2077 		c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
2078 			MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
2079 		c->ases &= ~MIPS_ASE_VZ; /* VZ of Loongson-3A2000/3000 is incomplete */
2080 		break;
2081 	case PRID_IMP_LOONGSON_64G:
2082 		c->cputype = CPU_LOONGSON64;
2083 		__cpu_name[cpu] = "ICT Loongson-3";
2084 		set_elf_platform(cpu, "loongson3a");
2085 		set_isa(c, MIPS_CPU_ISA_M64R2);
2086 		decode_cpucfg(c);
2087 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
2088 		break;
2089 	default:
2090 		panic("Unknown Loongson Processor ID!");
2091 		break;
2092 	}
2093 }
2094 #else
2095 static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { }
2096 #endif
2097 
2098 static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
2099 {
2100 	decode_configs(c);
2101 
2102 	/*
2103 	 * XBurst misses a config2 register, so config3 decode was skipped in
2104 	 * decode_configs().
2105 	 */
2106 	decode_config3(c);
2107 
2108 	/* XBurst does not implement the CP0 counter. */
2109 	c->options &= ~MIPS_CPU_COUNTER;
2110 	BUG_ON(!__builtin_constant_p(cpu_has_counter) || cpu_has_counter);
2111 
2112 	switch (c->processor_id & PRID_IMP_MASK) {
2113 	case PRID_IMP_XBURST_REV1:
2114 
2115 		/*
2116 		 * The XBurst core by default attempts to avoid branch target
2117 		 * buffer lookups by detecting & special casing loops. This
2118 		 * feature will cause BogoMIPS and lpj calculate in error.
2119 		 * Set cp0 config7 bit 4 to disable this feature.
2120 		 */
2121 		set_c0_config7(MIPS_CONF7_BTB_LOOP_EN);
2122 
2123 		switch (c->processor_id & PRID_COMP_MASK) {
2124 
2125 		/*
2126 		 * The config0 register in the XBurst CPUs with a processor ID of
2127 		 * PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 compatible,
2128 		 * but they don't actually support this ISA.
2129 		 */
2130 		case PRID_COMP_INGENIC_D0:
2131 			c->isa_level &= ~MIPS_CPU_ISA_M32R2;
2132 			break;
2133 
2134 		/*
2135 		 * The config0 register in the XBurst CPUs with a processor ID of
2136 		 * PRID_COMP_INGENIC_D1 has an abandoned huge page tlb mode, this
2137 		 * mode is not compatible with the MIPS standard, it will cause
2138 		 * tlbmiss and into an infinite loop (line 21 in the tlb-funcs.S)
2139 		 * when starting the init process. After chip reset, the default
2140 		 * is HPTLB mode, Write 0xa9000000 to cp0 register 5 sel 4 to
2141 		 * switch back to VTLB mode to prevent getting stuck.
2142 		 */
2143 		case PRID_COMP_INGENIC_D1:
2144 			write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);
2145 			break;
2146 
2147 		default:
2148 			break;
2149 		}
2150 		fallthrough;
2151 	case PRID_IMP_XBURST_REV2:
2152 		c->cputype = CPU_XBURST;
2153 		c->writecombine = _CACHE_UNCACHED_ACCELERATED;
2154 		__cpu_name[cpu] = "Ingenic XBurst";
2155 		break;
2156 
2157 	default:
2158 		panic("Unknown Ingenic Processor ID!");
2159 		break;
2160 	}
2161 }
2162 
2163 static inline void cpu_probe_netlogic(struct cpuinfo_mips *c, int cpu)
2164 {
2165 	decode_configs(c);
2166 
2167 	if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_NETLOGIC_AU13XX) {
2168 		c->cputype = CPU_ALCHEMY;
2169 		__cpu_name[cpu] = "Au1300";
2170 		/* following stuff is not for Alchemy */
2171 		return;
2172 	}
2173 
2174 	c->options = (MIPS_CPU_TLB	 |
2175 			MIPS_CPU_4KEX	 |
2176 			MIPS_CPU_COUNTER |
2177 			MIPS_CPU_DIVEC	 |
2178 			MIPS_CPU_WATCH	 |
2179 			MIPS_CPU_EJTAG	 |
2180 			MIPS_CPU_LLSC);
2181 
2182 	switch (c->processor_id & PRID_IMP_MASK) {
2183 	case PRID_IMP_NETLOGIC_XLP2XX:
2184 	case PRID_IMP_NETLOGIC_XLP9XX:
2185 	case PRID_IMP_NETLOGIC_XLP5XX:
2186 		c->cputype = CPU_XLP;
2187 		__cpu_name[cpu] = "Broadcom XLPII";
2188 		break;
2189 
2190 	case PRID_IMP_NETLOGIC_XLP8XX:
2191 	case PRID_IMP_NETLOGIC_XLP3XX:
2192 		c->cputype = CPU_XLP;
2193 		__cpu_name[cpu] = "Netlogic XLP";
2194 		break;
2195 
2196 	case PRID_IMP_NETLOGIC_XLR732:
2197 	case PRID_IMP_NETLOGIC_XLR716:
2198 	case PRID_IMP_NETLOGIC_XLR532:
2199 	case PRID_IMP_NETLOGIC_XLR308:
2200 	case PRID_IMP_NETLOGIC_XLR532C:
2201 	case PRID_IMP_NETLOGIC_XLR516C:
2202 	case PRID_IMP_NETLOGIC_XLR508C:
2203 	case PRID_IMP_NETLOGIC_XLR308C:
2204 		c->cputype = CPU_XLR;
2205 		__cpu_name[cpu] = "Netlogic XLR";
2206 		break;
2207 
2208 	case PRID_IMP_NETLOGIC_XLS608:
2209 	case PRID_IMP_NETLOGIC_XLS408:
2210 	case PRID_IMP_NETLOGIC_XLS404:
2211 	case PRID_IMP_NETLOGIC_XLS208:
2212 	case PRID_IMP_NETLOGIC_XLS204:
2213 	case PRID_IMP_NETLOGIC_XLS108:
2214 	case PRID_IMP_NETLOGIC_XLS104:
2215 	case PRID_IMP_NETLOGIC_XLS616B:
2216 	case PRID_IMP_NETLOGIC_XLS608B:
2217 	case PRID_IMP_NETLOGIC_XLS416B:
2218 	case PRID_IMP_NETLOGIC_XLS412B:
2219 	case PRID_IMP_NETLOGIC_XLS408B:
2220 	case PRID_IMP_NETLOGIC_XLS404B:
2221 		c->cputype = CPU_XLR;
2222 		__cpu_name[cpu] = "Netlogic XLS";
2223 		break;
2224 
2225 	default:
2226 		pr_info("Unknown Netlogic chip id [%02x]!\n",
2227 		       c->processor_id);
2228 		c->cputype = CPU_XLR;
2229 		break;
2230 	}
2231 
2232 	if (c->cputype == CPU_XLP) {
2233 		set_isa(c, MIPS_CPU_ISA_M64R2);
2234 		c->options |= (MIPS_CPU_FPU | MIPS_CPU_ULRI | MIPS_CPU_MCHECK);
2235 		/* This will be updated again after all threads are woken up */
2236 		c->tlbsize = ((read_c0_config6() >> 16) & 0xffff) + 1;
2237 	} else {
2238 		set_isa(c, MIPS_CPU_ISA_M64R1);
2239 		c->tlbsize = ((read_c0_config1() >> 25) & 0x3f) + 1;
2240 	}
2241 	c->kscratch_mask = 0xf;
2242 }
2243 
2244 #ifdef CONFIG_64BIT
2245 /* For use by uaccess.h */
2246 u64 __ua_limit;
2247 EXPORT_SYMBOL(__ua_limit);
2248 #endif
2249 
2250 const char *__cpu_name[NR_CPUS];
2251 const char *__elf_platform;
2252 const char *__elf_base_platform;
2253 
2254 void cpu_probe(void)
2255 {
2256 	struct cpuinfo_mips *c = &current_cpu_data;
2257 	unsigned int cpu = smp_processor_id();
2258 
2259 	/*
2260 	 * Set a default elf platform, cpu probe may later
2261 	 * overwrite it with a more precise value
2262 	 */
2263 	set_elf_platform(cpu, "mips");
2264 
2265 	c->processor_id = PRID_IMP_UNKNOWN;
2266 	c->fpu_id	= FPIR_IMP_NONE;
2267 	c->cputype	= CPU_UNKNOWN;
2268 	c->writecombine = _CACHE_UNCACHED;
2269 
2270 	c->fpu_csr31	= FPU_CSR_RN;
2271 	c->fpu_msk31	= FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
2272 
2273 	c->processor_id = read_c0_prid();
2274 	switch (c->processor_id & PRID_COMP_MASK) {
2275 	case PRID_COMP_LEGACY:
2276 		cpu_probe_legacy(c, cpu);
2277 		break;
2278 	case PRID_COMP_MIPS:
2279 		cpu_probe_mips(c, cpu);
2280 		break;
2281 	case PRID_COMP_ALCHEMY:
2282 		cpu_probe_alchemy(c, cpu);
2283 		break;
2284 	case PRID_COMP_SIBYTE:
2285 		cpu_probe_sibyte(c, cpu);
2286 		break;
2287 	case PRID_COMP_BROADCOM:
2288 		cpu_probe_broadcom(c, cpu);
2289 		break;
2290 	case PRID_COMP_SANDCRAFT:
2291 		cpu_probe_sandcraft(c, cpu);
2292 		break;
2293 	case PRID_COMP_NXP:
2294 		cpu_probe_nxp(c, cpu);
2295 		break;
2296 	case PRID_COMP_CAVIUM:
2297 		cpu_probe_cavium(c, cpu);
2298 		break;
2299 	case PRID_COMP_LOONGSON:
2300 		cpu_probe_loongson(c, cpu);
2301 		break;
2302 	case PRID_COMP_INGENIC_D0:
2303 	case PRID_COMP_INGENIC_D1:
2304 	case PRID_COMP_INGENIC_E1:
2305 		cpu_probe_ingenic(c, cpu);
2306 		break;
2307 	case PRID_COMP_NETLOGIC:
2308 		cpu_probe_netlogic(c, cpu);
2309 		break;
2310 	}
2311 
2312 	BUG_ON(!__cpu_name[cpu]);
2313 	BUG_ON(c->cputype == CPU_UNKNOWN);
2314 
2315 	/*
2316 	 * Platform code can force the cpu type to optimize code
2317 	 * generation. In that case be sure the cpu type is correctly
2318 	 * manually setup otherwise it could trigger some nasty bugs.
2319 	 */
2320 	BUG_ON(current_cpu_type() != c->cputype);
2321 
2322 	if (cpu_has_rixi) {
2323 		/* Enable the RIXI exceptions */
2324 		set_c0_pagegrain(PG_IEC);
2325 		back_to_back_c0_hazard();
2326 		/* Verify the IEC bit is set */
2327 		if (read_c0_pagegrain() & PG_IEC)
2328 			c->options |= MIPS_CPU_RIXIEX;
2329 	}
2330 
2331 	if (mips_fpu_disabled)
2332 		c->options &= ~MIPS_CPU_FPU;
2333 
2334 	if (mips_dsp_disabled)
2335 		c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
2336 
2337 	if (mips_htw_disabled) {
2338 		c->options &= ~MIPS_CPU_HTW;
2339 		write_c0_pwctl(read_c0_pwctl() &
2340 			       ~(1 << MIPS_PWCTL_PWEN_SHIFT));
2341 	}
2342 
2343 	if (c->options & MIPS_CPU_FPU)
2344 		cpu_set_fpu_opts(c);
2345 	else
2346 		cpu_set_nofpu_opts(c);
2347 
2348 	if (cpu_has_bp_ghist)
2349 		write_c0_r10k_diag(read_c0_r10k_diag() |
2350 				   R10K_DIAG_E_GHIST);
2351 
2352 	if (cpu_has_mips_r2_r6) {
2353 		c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
2354 		/* R2 has Performance Counter Interrupt indicator */
2355 		c->options |= MIPS_CPU_PCI;
2356 	}
2357 	else
2358 		c->srsets = 1;
2359 
2360 	if (cpu_has_mips_r6)
2361 		elf_hwcap |= HWCAP_MIPS_R6;
2362 
2363 	if (cpu_has_msa) {
2364 		c->msa_id = cpu_get_msa_id();
2365 		WARN(c->msa_id & MSA_IR_WRPF,
2366 		     "Vector register partitioning unimplemented!");
2367 		elf_hwcap |= HWCAP_MIPS_MSA;
2368 	}
2369 
2370 	if (cpu_has_mips16)
2371 		elf_hwcap |= HWCAP_MIPS_MIPS16;
2372 
2373 	if (cpu_has_mdmx)
2374 		elf_hwcap |= HWCAP_MIPS_MDMX;
2375 
2376 	if (cpu_has_mips3d)
2377 		elf_hwcap |= HWCAP_MIPS_MIPS3D;
2378 
2379 	if (cpu_has_smartmips)
2380 		elf_hwcap |= HWCAP_MIPS_SMARTMIPS;
2381 
2382 	if (cpu_has_dsp)
2383 		elf_hwcap |= HWCAP_MIPS_DSP;
2384 
2385 	if (cpu_has_dsp2)
2386 		elf_hwcap |= HWCAP_MIPS_DSP2;
2387 
2388 	if (cpu_has_dsp3)
2389 		elf_hwcap |= HWCAP_MIPS_DSP3;
2390 
2391 	if (cpu_has_mips16e2)
2392 		elf_hwcap |= HWCAP_MIPS_MIPS16E2;
2393 
2394 	if (cpu_has_loongson_mmi)
2395 		elf_hwcap |= HWCAP_LOONGSON_MMI;
2396 
2397 	if (cpu_has_loongson_ext)
2398 		elf_hwcap |= HWCAP_LOONGSON_EXT;
2399 
2400 	if (cpu_has_loongson_ext2)
2401 		elf_hwcap |= HWCAP_LOONGSON_EXT2;
2402 
2403 	if (cpu_has_vz)
2404 		cpu_probe_vz(c);
2405 
2406 	cpu_probe_vmbits(c);
2407 
2408 	/* Synthesize CPUCFG data if running on Loongson processors;
2409 	 * no-op otherwise.
2410 	 *
2411 	 * This looks at previously probed features, so keep this at bottom.
2412 	 */
2413 	loongson3_cpucfg_synthesize_data(c);
2414 
2415 #ifdef CONFIG_64BIT
2416 	if (cpu == 0)
2417 		__ua_limit = ~((1ull << cpu_vmbits) - 1);
2418 #endif
2419 }
2420 
2421 void cpu_report(void)
2422 {
2423 	struct cpuinfo_mips *c = &current_cpu_data;
2424 
2425 	pr_info("CPU%d revision is: %08x (%s)\n",
2426 		smp_processor_id(), c->processor_id, cpu_name_string());
2427 	if (c->options & MIPS_CPU_FPU)
2428 		printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
2429 	if (cpu_has_msa)
2430 		pr_info("MSA revision is: %08x\n", c->msa_id);
2431 }
2432 
2433 void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
2434 {
2435 	/* Ensure the core number fits in the field */
2436 	WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
2437 			   MIPS_GLOBALNUMBER_CLUSTER_SHF));
2438 
2439 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
2440 	cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
2441 }
2442 
2443 void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
2444 {
2445 	/* Ensure the core number fits in the field */
2446 	WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
2447 
2448 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
2449 	cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
2450 }
2451 
2452 void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
2453 {
2454 	/* Ensure the VP(E) ID fits in the field */
2455 	WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
2456 
2457 	/* Ensure we're not using VP(E)s without support */
2458 	WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
2459 		!IS_ENABLED(CONFIG_CPU_MIPSR6));
2460 
2461 	cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
2462 	cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
2463 }
2464