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Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec...
[linux-2.6.git] / arch / mips / kernel / cpu-probe.c
1 /*
2  * Processor capabilities determination functions.
3  *
4  * Copyright (C) xxxx  the Anonymous
5  * Copyright (C) 1994 - 2006 Ralf Baechle
6  * Copyright (C) 2003, 2004  Maciej W. Rozycki
7  * Copyright (C) 2001, 2004  MIPS Inc.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/ptrace.h>
17 #include <linux/smp.h>
18 #include <linux/stddef.h>
19 #include <linux/module.h>
20
21 #include <asm/bugs.h>
22 #include <asm/cpu.h>
23 #include <asm/fpu.h>
24 #include <asm/mipsregs.h>
25 #include <asm/system.h>
26 #include <asm/watch.h>
27 #include <asm/spram.h>
28 /*
29  * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
30  * the implementation of the "wait" feature differs between CPU families. This
31  * points to the function that implements CPU specific wait.
32  * The wait instruction stops the pipeline and reduces the power consumption of
33  * the CPU very much.
34  */
35 void (*cpu_wait)(void);
36 EXPORT_SYMBOL(cpu_wait);
37
38 static void r3081_wait(void)
39 {
40         unsigned long cfg = read_c0_conf();
41         write_c0_conf(cfg | R30XX_CONF_HALT);
42 }
43
44 static void r39xx_wait(void)
45 {
46         local_irq_disable();
47         if (!need_resched())
48                 write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
49         local_irq_enable();
50 }
51
52 extern void r4k_wait(void);
53
54 /*
55  * This variant is preferable as it allows testing need_resched and going to
56  * sleep depending on the outcome atomically.  Unfortunately the "It is
57  * implementation-dependent whether the pipeline restarts when a non-enabled
58  * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
59  * using this version a gamble.
60  */
61 void r4k_wait_irqoff(void)
62 {
63         local_irq_disable();
64         if (!need_resched())
65                 __asm__("       .set    push            \n"
66                         "       .set    mips3           \n"
67                         "       wait                    \n"
68                         "       .set    pop             \n");
69         local_irq_enable();
70         __asm__("       .globl __pastwait       \n"
71                 "__pastwait:                    \n");
72         return;
73 }
74
75 /*
76  * The RM7000 variant has to handle erratum 38.  The workaround is to not
77  * have any pending stores when the WAIT instruction is executed.
78  */
79 static void rm7k_wait_irqoff(void)
80 {
81         local_irq_disable();
82         if (!need_resched())
83                 __asm__(
84                 "       .set    push                                    \n"
85                 "       .set    mips3                                   \n"
86                 "       .set    noat                                    \n"
87                 "       mfc0    $1, $12                                 \n"
88                 "       sync                                            \n"
89                 "       mtc0    $1, $12         # stalls until W stage  \n"
90                 "       wait                                            \n"
91                 "       mtc0    $1, $12         # stalls until W stage  \n"
92                 "       .set    pop                                     \n");
93         local_irq_enable();
94 }
95
96 /*
97  * The Au1xxx wait is available only if using 32khz counter or
98  * external timer source, but specifically not CP0 Counter.
99  * alchemy/common/time.c may override cpu_wait!
100  */
101 static void au1k_wait(void)
102 {
103         __asm__("       .set    mips3                   \n"
104                 "       cache   0x14, 0(%0)             \n"
105                 "       cache   0x14, 32(%0)            \n"
106                 "       sync                            \n"
107                 "       nop                             \n"
108                 "       wait                            \n"
109                 "       nop                             \n"
110                 "       nop                             \n"
111                 "       nop                             \n"
112                 "       nop                             \n"
113                 "       .set    mips0                   \n"
114                 : : "r" (au1k_wait));
115 }
116
117 static int __initdata nowait;
118
119 static int __init wait_disable(char *s)
120 {
121         nowait = 1;
122
123         return 1;
124 }
125
126 __setup("nowait", wait_disable);
127
128 void __init check_wait(void)
129 {
130         struct cpuinfo_mips *c = &current_cpu_data;
131
132         if (nowait) {
133                 printk("Wait instruction disabled.\n");
134                 return;
135         }
136
137         switch (c->cputype) {
138         case CPU_R3081:
139         case CPU_R3081E:
140                 cpu_wait = r3081_wait;
141                 break;
142         case CPU_TX3927:
143                 cpu_wait = r39xx_wait;
144                 break;
145         case CPU_R4200:
146 /*      case CPU_R4300: */
147         case CPU_R4600:
148         case CPU_R4640:
149         case CPU_R4650:
150         case CPU_R4700:
151         case CPU_R5000:
152         case CPU_R5500:
153         case CPU_NEVADA:
154         case CPU_4KC:
155         case CPU_4KEC:
156         case CPU_4KSC:
157         case CPU_5KC:
158         case CPU_25KF:
159         case CPU_PR4450:
160         case CPU_BCM3302:
161         case CPU_BCM6338:
162         case CPU_BCM6348:
163         case CPU_BCM6358:
164         case CPU_CAVIUM_OCTEON:
165                 cpu_wait = r4k_wait;
166                 break;
167
168         case CPU_RM7000:
169                 cpu_wait = rm7k_wait_irqoff;
170                 break;
171
172         case CPU_24K:
173         case CPU_34K:
174         case CPU_1004K:
175                 cpu_wait = r4k_wait;
176                 if (read_c0_config7() & MIPS_CONF7_WII)
177                         cpu_wait = r4k_wait_irqoff;
178                 break;
179
180         case CPU_74K:
181                 cpu_wait = r4k_wait;
182                 if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
183                         cpu_wait = r4k_wait_irqoff;
184                 break;
185
186         case CPU_TX49XX:
187                 cpu_wait = r4k_wait_irqoff;
188                 break;
189         case CPU_ALCHEMY:
190                 cpu_wait = au1k_wait;
191                 break;
192         case CPU_20KC:
193                 /*
194                  * WAIT on Rev1.0 has E1, E2, E3 and E16.
195                  * WAIT on Rev2.0 and Rev3.0 has E16.
196                  * Rev3.1 WAIT is nop, why bother
197                  */
198                 if ((c->processor_id & 0xff) <= 0x64)
199                         break;
200
201                 /*
202                  * Another rev is incremeting c0_count at a reduced clock
203                  * rate while in WAIT mode.  So we basically have the choice
204                  * between using the cp0 timer as clocksource or avoiding
205                  * the WAIT instruction.  Until more details are known,
206                  * disable the use of WAIT for 20Kc entirely.
207                    cpu_wait = r4k_wait;
208                  */
209                 break;
210         case CPU_RM9000:
211                 if ((c->processor_id & 0x00ff) >= 0x40)
212                         cpu_wait = r4k_wait;
213                 break;
214         default:
215                 break;
216         }
217 }
218
219 static inline void check_errata(void)
220 {
221         struct cpuinfo_mips *c = &current_cpu_data;
222
223         switch (c->cputype) {
224         case CPU_34K:
225                 /*
226                  * Erratum "RPS May Cause Incorrect Instruction Execution"
227                  * This code only handles VPE0, any SMP/SMTC/RTOS code
228                  * making use of VPE1 will be responsable for that VPE.
229                  */
230                 if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
231                         write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
232                 break;
233         default:
234                 break;
235         }
236 }
237
238 void __init check_bugs32(void)
239 {
240         check_errata();
241 }
242
243 /*
244  * Probe whether cpu has config register by trying to play with
245  * alternate cache bit and see whether it matters.
246  * It's used by cpu_probe to distinguish between R3000A and R3081.
247  */
248 static inline int cpu_has_confreg(void)
249 {
250 #ifdef CONFIG_CPU_R3000
251         extern unsigned long r3k_cache_size(unsigned long);
252         unsigned long size1, size2;
253         unsigned long cfg = read_c0_conf();
254
255         size1 = r3k_cache_size(ST0_ISC);
256         write_c0_conf(cfg ^ R30XX_CONF_AC);
257         size2 = r3k_cache_size(ST0_ISC);
258         write_c0_conf(cfg);
259         return size1 != size2;
260 #else
261         return 0;
262 #endif
263 }
264
265 /*
266  * Get the FPU Implementation/Revision.
267  */
268 static inline unsigned long cpu_get_fpu_id(void)
269 {
270         unsigned long tmp, fpu_id;
271
272         tmp = read_c0_status();
273         __enable_fpu();
274         fpu_id = read_32bit_cp1_register(CP1_REVISION);
275         write_c0_status(tmp);
276         return fpu_id;
277 }
278
279 /*
280  * Check the CPU has an FPU the official way.
281  */
282 static inline int __cpu_has_fpu(void)
283 {
284         return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
285 }
286
287 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
288                 | MIPS_CPU_COUNTER)
289
290 static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
291 {
292         switch (c->processor_id & 0xff00) {
293         case PRID_IMP_R2000:
294                 c->cputype = CPU_R2000;
295                 __cpu_name[cpu] = "R2000";
296                 c->isa_level = MIPS_CPU_ISA_I;
297                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
298                              MIPS_CPU_NOFPUEX;
299                 if (__cpu_has_fpu())
300                         c->options |= MIPS_CPU_FPU;
301                 c->tlbsize = 64;
302                 break;
303         case PRID_IMP_R3000:
304                 if ((c->processor_id & 0xff) == PRID_REV_R3000A) {
305                         if (cpu_has_confreg()) {
306                                 c->cputype = CPU_R3081E;
307                                 __cpu_name[cpu] = "R3081";
308                         } else {
309                                 c->cputype = CPU_R3000A;
310                                 __cpu_name[cpu] = "R3000A";
311                         }
312                         break;
313                 } else {
314                         c->cputype = CPU_R3000;
315                         __cpu_name[cpu] = "R3000";
316                 }
317                 c->isa_level = MIPS_CPU_ISA_I;
318                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
319                              MIPS_CPU_NOFPUEX;
320                 if (__cpu_has_fpu())
321                         c->options |= MIPS_CPU_FPU;
322                 c->tlbsize = 64;
323                 break;
324         case PRID_IMP_R4000:
325                 if (read_c0_config() & CONF_SC) {
326                         if ((c->processor_id & 0xff) >= PRID_REV_R4400) {
327                                 c->cputype = CPU_R4400PC;
328                                 __cpu_name[cpu] = "R4400PC";
329                         } else {
330                                 c->cputype = CPU_R4000PC;
331                                 __cpu_name[cpu] = "R4000PC";
332                         }
333                 } else {
334                         if ((c->processor_id & 0xff) >= PRID_REV_R4400) {
335                                 c->cputype = CPU_R4400SC;
336                                 __cpu_name[cpu] = "R4400SC";
337                         } else {
338                                 c->cputype = CPU_R4000SC;
339                                 __cpu_name[cpu] = "R4000SC";
340                         }
341                 }
342
343                 c->isa_level = MIPS_CPU_ISA_III;
344                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
345                              MIPS_CPU_WATCH | MIPS_CPU_VCE |
346                              MIPS_CPU_LLSC;
347                 c->tlbsize = 48;
348                 break;
349         case PRID_IMP_VR41XX:
350                 switch (c->processor_id & 0xf0) {
351                 case PRID_REV_VR4111:
352                         c->cputype = CPU_VR4111;
353                         __cpu_name[cpu] = "NEC VR4111";
354                         break;
355                 case PRID_REV_VR4121:
356                         c->cputype = CPU_VR4121;
357                         __cpu_name[cpu] = "NEC VR4121";
358                         break;
359                 case PRID_REV_VR4122:
360                         if ((c->processor_id & 0xf) < 0x3) {
361                                 c->cputype = CPU_VR4122;
362                                 __cpu_name[cpu] = "NEC VR4122";
363                         } else {
364                                 c->cputype = CPU_VR4181A;
365                                 __cpu_name[cpu] = "NEC VR4181A";
366                         }
367                         break;
368                 case PRID_REV_VR4130:
369                         if ((c->processor_id & 0xf) < 0x4) {
370                                 c->cputype = CPU_VR4131;
371                                 __cpu_name[cpu] = "NEC VR4131";
372                         } else {
373                                 c->cputype = CPU_VR4133;
374                                 __cpu_name[cpu] = "NEC VR4133";
375                         }
376                         break;
377                 default:
378                         printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
379                         c->cputype = CPU_VR41XX;
380                         __cpu_name[cpu] = "NEC Vr41xx";
381                         break;
382                 }
383                 c->isa_level = MIPS_CPU_ISA_III;
384                 c->options = R4K_OPTS;
385                 c->tlbsize = 32;
386                 break;
387         case PRID_IMP_R4300:
388                 c->cputype = CPU_R4300;
389                 __cpu_name[cpu] = "R4300";
390                 c->isa_level = MIPS_CPU_ISA_III;
391                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
392                              MIPS_CPU_LLSC;
393                 c->tlbsize = 32;
394                 break;
395         case PRID_IMP_R4600:
396                 c->cputype = CPU_R4600;
397                 __cpu_name[cpu] = "R4600";
398                 c->isa_level = MIPS_CPU_ISA_III;
399                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
400                              MIPS_CPU_LLSC;
401                 c->tlbsize = 48;
402                 break;
403         #if 0
404         case PRID_IMP_R4650:
405                 /*
406                  * This processor doesn't have an MMU, so it's not
407                  * "real easy" to run Linux on it. It is left purely
408                  * for documentation.  Commented out because it shares
409                  * it's c0_prid id number with the TX3900.
410                  */
411                 c->cputype = CPU_R4650;
412                 __cpu_name[cpu] = "R4650";
413                 c->isa_level = MIPS_CPU_ISA_III;
414                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
415                 c->tlbsize = 48;
416                 break;
417         #endif
418         case PRID_IMP_TX39:
419                 c->isa_level = MIPS_CPU_ISA_I;
420                 c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
421
422                 if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
423                         c->cputype = CPU_TX3927;
424                         __cpu_name[cpu] = "TX3927";
425                         c->tlbsize = 64;
426                 } else {
427                         switch (c->processor_id & 0xff) {
428                         case PRID_REV_TX3912:
429                                 c->cputype = CPU_TX3912;
430                                 __cpu_name[cpu] = "TX3912";
431                                 c->tlbsize = 32;
432                                 break;
433                         case PRID_REV_TX3922:
434                                 c->cputype = CPU_TX3922;
435                                 __cpu_name[cpu] = "TX3922";
436                                 c->tlbsize = 64;
437                                 break;
438                         }
439                 }
440                 break;
441         case PRID_IMP_R4700:
442                 c->cputype = CPU_R4700;
443                 __cpu_name[cpu] = "R4700";
444                 c->isa_level = MIPS_CPU_ISA_III;
445                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
446                              MIPS_CPU_LLSC;
447                 c->tlbsize = 48;
448                 break;
449         case PRID_IMP_TX49:
450                 c->cputype = CPU_TX49XX;
451                 __cpu_name[cpu] = "R49XX";
452                 c->isa_level = MIPS_CPU_ISA_III;
453                 c->options = R4K_OPTS | MIPS_CPU_LLSC;
454                 if (!(c->processor_id & 0x08))
455                         c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
456                 c->tlbsize = 48;
457                 break;
458         case PRID_IMP_R5000:
459                 c->cputype = CPU_R5000;
460                 __cpu_name[cpu] = "R5000";
461                 c->isa_level = MIPS_CPU_ISA_IV;
462                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
463                              MIPS_CPU_LLSC;
464                 c->tlbsize = 48;
465                 break;
466         case PRID_IMP_R5432:
467                 c->cputype = CPU_R5432;
468                 __cpu_name[cpu] = "R5432";
469                 c->isa_level = MIPS_CPU_ISA_IV;
470                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
471                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
472                 c->tlbsize = 48;
473                 break;
474         case PRID_IMP_R5500:
475                 c->cputype = CPU_R5500;
476                 __cpu_name[cpu] = "R5500";
477                 c->isa_level = MIPS_CPU_ISA_IV;
478                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
479                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
480                 c->tlbsize = 48;
481                 break;
482         case PRID_IMP_NEVADA:
483                 c->cputype = CPU_NEVADA;
484                 __cpu_name[cpu] = "Nevada";
485                 c->isa_level = MIPS_CPU_ISA_IV;
486                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
487                              MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
488                 c->tlbsize = 48;
489                 break;
490         case PRID_IMP_R6000:
491                 c->cputype = CPU_R6000;
492                 __cpu_name[cpu] = "R6000";
493                 c->isa_level = MIPS_CPU_ISA_II;
494                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
495                              MIPS_CPU_LLSC;
496                 c->tlbsize = 32;
497                 break;
498         case PRID_IMP_R6000A:
499                 c->cputype = CPU_R6000A;
500                 __cpu_name[cpu] = "R6000A";
501                 c->isa_level = MIPS_CPU_ISA_II;
502                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
503                              MIPS_CPU_LLSC;
504                 c->tlbsize = 32;
505                 break;
506         case PRID_IMP_RM7000:
507                 c->cputype = CPU_RM7000;
508                 __cpu_name[cpu] = "RM7000";
509                 c->isa_level = MIPS_CPU_ISA_IV;
510                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
511                              MIPS_CPU_LLSC;
512                 /*
513                  * Undocumented RM7000:  Bit 29 in the info register of
514                  * the RM7000 v2.0 indicates if the TLB has 48 or 64
515                  * entries.
516                  *
517                  * 29      1 =>    64 entry JTLB
518                  *         0 =>    48 entry JTLB
519                  */
520                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
521                 break;
522         case PRID_IMP_RM9000:
523                 c->cputype = CPU_RM9000;
524                 __cpu_name[cpu] = "RM9000";
525                 c->isa_level = MIPS_CPU_ISA_IV;
526                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
527                              MIPS_CPU_LLSC;
528                 /*
529                  * Bit 29 in the info register of the RM9000
530                  * indicates if the TLB has 48 or 64 entries.
531                  *
532                  * 29      1 =>    64 entry JTLB
533                  *         0 =>    48 entry JTLB
534                  */
535                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
536                 break;
537         case PRID_IMP_R8000:
538                 c->cputype = CPU_R8000;
539                 __cpu_name[cpu] = "RM8000";
540                 c->isa_level = MIPS_CPU_ISA_IV;
541                 c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
542                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
543                              MIPS_CPU_LLSC;
544                 c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
545                 break;
546         case PRID_IMP_R10000:
547                 c->cputype = CPU_R10000;
548                 __cpu_name[cpu] = "R10000";
549                 c->isa_level = MIPS_CPU_ISA_IV;
550                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
551                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
552                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
553                              MIPS_CPU_LLSC;
554                 c->tlbsize = 64;
555                 break;
556         case PRID_IMP_R12000:
557                 c->cputype = CPU_R12000;
558                 __cpu_name[cpu] = "R12000";
559                 c->isa_level = MIPS_CPU_ISA_IV;
560                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
561                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
562                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
563                              MIPS_CPU_LLSC;
564                 c->tlbsize = 64;
565                 break;
566         case PRID_IMP_R14000:
567                 c->cputype = CPU_R14000;
568                 __cpu_name[cpu] = "R14000";
569                 c->isa_level = MIPS_CPU_ISA_IV;
570                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
571                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
572                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
573                              MIPS_CPU_LLSC;
574                 c->tlbsize = 64;
575                 break;
576         case PRID_IMP_LOONGSON2:
577                 c->cputype = CPU_LOONGSON2;
578                 __cpu_name[cpu] = "ICT Loongson-2";
579                 c->isa_level = MIPS_CPU_ISA_III;
580                 c->options = R4K_OPTS |
581                              MIPS_CPU_FPU | MIPS_CPU_LLSC |
582                              MIPS_CPU_32FPR;
583                 c->tlbsize = 64;
584                 break;
585         }
586 }
587
588 static char unknown_isa[] __cpuinitdata = KERN_ERR \
589         "Unsupported ISA type, c0.config0: %d.";
590
591 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
592 {
593         unsigned int config0;
594         int isa;
595
596         config0 = read_c0_config();
597
598         if (((config0 & MIPS_CONF_MT) >> 7) == 1)
599                 c->options |= MIPS_CPU_TLB;
600         isa = (config0 & MIPS_CONF_AT) >> 13;
601         switch (isa) {
602         case 0:
603                 switch ((config0 & MIPS_CONF_AR) >> 10) {
604                 case 0:
605                         c->isa_level = MIPS_CPU_ISA_M32R1;
606                         break;
607                 case 1:
608                         c->isa_level = MIPS_CPU_ISA_M32R2;
609                         break;
610                 default:
611                         goto unknown;
612                 }
613                 break;
614         case 2:
615                 switch ((config0 & MIPS_CONF_AR) >> 10) {
616                 case 0:
617                         c->isa_level = MIPS_CPU_ISA_M64R1;
618                         break;
619                 case 1:
620                         c->isa_level = MIPS_CPU_ISA_M64R2;
621                         break;
622                 default:
623                         goto unknown;
624                 }
625                 break;
626         default:
627                 goto unknown;
628         }
629
630         return config0 & MIPS_CONF_M;
631
632 unknown:
633         panic(unknown_isa, config0);
634 }
635
636 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
637 {
638         unsigned int config1;
639
640         config1 = read_c0_config1();
641
642         if (config1 & MIPS_CONF1_MD)
643                 c->ases |= MIPS_ASE_MDMX;
644         if (config1 & MIPS_CONF1_WR)
645                 c->options |= MIPS_CPU_WATCH;
646         if (config1 & MIPS_CONF1_CA)
647                 c->ases |= MIPS_ASE_MIPS16;
648         if (config1 & MIPS_CONF1_EP)
649                 c->options |= MIPS_CPU_EJTAG;
650         if (config1 & MIPS_CONF1_FP) {
651                 c->options |= MIPS_CPU_FPU;
652                 c->options |= MIPS_CPU_32FPR;
653         }
654         if (cpu_has_tlb)
655                 c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
656
657         return config1 & MIPS_CONF_M;
658 }
659
660 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
661 {
662         unsigned int config2;
663
664         config2 = read_c0_config2();
665
666         if (config2 & MIPS_CONF2_SL)
667                 c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
668
669         return config2 & MIPS_CONF_M;
670 }
671
672 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
673 {
674         unsigned int config3;
675
676         config3 = read_c0_config3();
677
678         if (config3 & MIPS_CONF3_SM)
679                 c->ases |= MIPS_ASE_SMARTMIPS;
680         if (config3 & MIPS_CONF3_DSP)
681                 c->ases |= MIPS_ASE_DSP;
682         if (config3 & MIPS_CONF3_VINT)
683                 c->options |= MIPS_CPU_VINT;
684         if (config3 & MIPS_CONF3_VEIC)
685                 c->options |= MIPS_CPU_VEIC;
686         if (config3 & MIPS_CONF3_MT)
687                 c->ases |= MIPS_ASE_MIPSMT;
688         if (config3 & MIPS_CONF3_ULRI)
689                 c->options |= MIPS_CPU_ULRI;
690
691         return config3 & MIPS_CONF_M;
692 }
693
694 static void __cpuinit decode_configs(struct cpuinfo_mips *c)
695 {
696         int ok;
697
698         /* MIPS32 or MIPS64 compliant CPU.  */
699         c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
700                      MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
701
702         c->scache.flags = MIPS_CACHE_NOT_PRESENT;
703
704         ok = decode_config0(c);                 /* Read Config registers.  */
705         BUG_ON(!ok);                            /* Arch spec violation!  */
706         if (ok)
707                 ok = decode_config1(c);
708         if (ok)
709                 ok = decode_config2(c);
710         if (ok)
711                 ok = decode_config3(c);
712
713         mips_probe_watch_registers(c);
714 }
715
716 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
717 {
718         decode_configs(c);
719         switch (c->processor_id & 0xff00) {
720         case PRID_IMP_4KC:
721                 c->cputype = CPU_4KC;
722                 __cpu_name[cpu] = "MIPS 4Kc";
723                 break;
724         case PRID_IMP_4KEC:
725                 c->cputype = CPU_4KEC;
726                 __cpu_name[cpu] = "MIPS 4KEc";
727                 break;
728         case PRID_IMP_4KECR2:
729                 c->cputype = CPU_4KEC;
730                 __cpu_name[cpu] = "MIPS 4KEc";
731                 break;
732         case PRID_IMP_4KSC:
733         case PRID_IMP_4KSD:
734                 c->cputype = CPU_4KSC;
735                 __cpu_name[cpu] = "MIPS 4KSc";
736                 break;
737         case PRID_IMP_5KC:
738                 c->cputype = CPU_5KC;
739                 __cpu_name[cpu] = "MIPS 5Kc";
740                 break;
741         case PRID_IMP_20KC:
742                 c->cputype = CPU_20KC;
743                 __cpu_name[cpu] = "MIPS 20Kc";
744                 break;
745         case PRID_IMP_24K:
746         case PRID_IMP_24KE:
747                 c->cputype = CPU_24K;
748                 __cpu_name[cpu] = "MIPS 24Kc";
749                 break;
750         case PRID_IMP_25KF:
751                 c->cputype = CPU_25KF;
752                 __cpu_name[cpu] = "MIPS 25Kc";
753                 break;
754         case PRID_IMP_34K:
755                 c->cputype = CPU_34K;
756                 __cpu_name[cpu] = "MIPS 34Kc";
757                 break;
758         case PRID_IMP_74K:
759                 c->cputype = CPU_74K;
760                 __cpu_name[cpu] = "MIPS 74Kc";
761                 break;
762         case PRID_IMP_1004K:
763                 c->cputype = CPU_1004K;
764                 __cpu_name[cpu] = "MIPS 1004Kc";
765                 break;
766         }
767
768         spram_config();
769 }
770
771 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
772 {
773         decode_configs(c);
774         switch (c->processor_id & 0xff00) {
775         case PRID_IMP_AU1_REV1:
776         case PRID_IMP_AU1_REV2:
777                 c->cputype = CPU_ALCHEMY;
778                 switch ((c->processor_id >> 24) & 0xff) {
779                 case 0:
780                         __cpu_name[cpu] = "Au1000";
781                         break;
782                 case 1:
783                         __cpu_name[cpu] = "Au1500";
784                         break;
785                 case 2:
786                         __cpu_name[cpu] = "Au1100";
787                         break;
788                 case 3:
789                         __cpu_name[cpu] = "Au1550";
790                         break;
791                 case 4:
792                         __cpu_name[cpu] = "Au1200";
793                         if ((c->processor_id & 0xff) == 2)
794                                 __cpu_name[cpu] = "Au1250";
795                         break;
796                 case 5:
797                         __cpu_name[cpu] = "Au1210";
798                         break;
799                 default:
800                         __cpu_name[cpu] = "Au1xxx";
801                         break;
802                 }
803                 break;
804         }
805 }
806
807 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
808 {
809         decode_configs(c);
810
811         switch (c->processor_id & 0xff00) {
812         case PRID_IMP_SB1:
813                 c->cputype = CPU_SB1;
814                 __cpu_name[cpu] = "SiByte SB1";
815                 /* FPU in pass1 is known to have issues. */
816                 if ((c->processor_id & 0xff) < 0x02)
817                         c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
818                 break;
819         case PRID_IMP_SB1A:
820                 c->cputype = CPU_SB1A;
821                 __cpu_name[cpu] = "SiByte SB1A";
822                 break;
823         }
824 }
825
826 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
827 {
828         decode_configs(c);
829         switch (c->processor_id & 0xff00) {
830         case PRID_IMP_SR71000:
831                 c->cputype = CPU_SR71000;
832                 __cpu_name[cpu] = "Sandcraft SR71000";
833                 c->scache.ways = 8;
834                 c->tlbsize = 64;
835                 break;
836         }
837 }
838
839 static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
840 {
841         decode_configs(c);
842         switch (c->processor_id & 0xff00) {
843         case PRID_IMP_PR4450:
844                 c->cputype = CPU_PR4450;
845                 __cpu_name[cpu] = "Philips PR4450";
846                 c->isa_level = MIPS_CPU_ISA_M32R1;
847                 break;
848         }
849 }
850
851 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
852 {
853         decode_configs(c);
854         switch (c->processor_id & 0xff00) {
855         case PRID_IMP_BCM3302:
856          /* same as PRID_IMP_BCM6338 */
857                 c->cputype = CPU_BCM3302;
858                 __cpu_name[cpu] = "Broadcom BCM3302";
859                 break;
860         case PRID_IMP_BCM4710:
861                 c->cputype = CPU_BCM4710;
862                 __cpu_name[cpu] = "Broadcom BCM4710";
863                 break;
864         case PRID_IMP_BCM6345:
865                 c->cputype = CPU_BCM6345;
866                 __cpu_name[cpu] = "Broadcom BCM6345";
867                 break;
868         case PRID_IMP_BCM6348:
869                 c->cputype = CPU_BCM6348;
870                 __cpu_name[cpu] = "Broadcom BCM6348";
871                 break;
872         case PRID_IMP_BCM4350:
873                 switch (c->processor_id & 0xf0) {
874                 case PRID_REV_BCM6358:
875                         c->cputype = CPU_BCM6358;
876                         __cpu_name[cpu] = "Broadcom BCM6358";
877                         break;
878                 default:
879                         c->cputype = CPU_UNKNOWN;
880                         break;
881                 }
882                 break;
883         }
884 }
885
886 static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
887 {
888         decode_configs(c);
889         switch (c->processor_id & 0xff00) {
890         case PRID_IMP_CAVIUM_CN38XX:
891         case PRID_IMP_CAVIUM_CN31XX:
892         case PRID_IMP_CAVIUM_CN30XX:
893         case PRID_IMP_CAVIUM_CN58XX:
894         case PRID_IMP_CAVIUM_CN56XX:
895         case PRID_IMP_CAVIUM_CN50XX:
896         case PRID_IMP_CAVIUM_CN52XX:
897                 c->cputype = CPU_CAVIUM_OCTEON;
898                 __cpu_name[cpu] = "Cavium Octeon";
899                 break;
900         default:
901                 printk(KERN_INFO "Unknown Octeon chip!\n");
902                 c->cputype = CPU_UNKNOWN;
903                 break;
904         }
905 }
906
907 const char *__cpu_name[NR_CPUS];
908
909 __cpuinit void cpu_probe(void)
910 {
911         struct cpuinfo_mips *c = &current_cpu_data;
912         unsigned int cpu = smp_processor_id();
913
914         c->processor_id = PRID_IMP_UNKNOWN;
915         c->fpu_id       = FPIR_IMP_NONE;
916         c->cputype      = CPU_UNKNOWN;
917
918         c->processor_id = read_c0_prid();
919         switch (c->processor_id & 0xff0000) {
920         case PRID_COMP_LEGACY:
921                 cpu_probe_legacy(c, cpu);
922                 break;
923         case PRID_COMP_MIPS:
924                 cpu_probe_mips(c, cpu);
925                 break;
926         case PRID_COMP_ALCHEMY:
927                 cpu_probe_alchemy(c, cpu);
928                 break;
929         case PRID_COMP_SIBYTE:
930                 cpu_probe_sibyte(c, cpu);
931                 break;
932         case PRID_COMP_BROADCOM:
933                 cpu_probe_broadcom(c, cpu);
934                 break;
935         case PRID_COMP_SANDCRAFT:
936                 cpu_probe_sandcraft(c, cpu);
937                 break;
938         case PRID_COMP_NXP:
939                 cpu_probe_nxp(c, cpu);
940                 break;
941         case PRID_COMP_CAVIUM:
942                 cpu_probe_cavium(c, cpu);
943                 break;
944         }
945
946         BUG_ON(!__cpu_name[cpu]);
947         BUG_ON(c->cputype == CPU_UNKNOWN);
948
949         /*
950          * Platform code can force the cpu type to optimize code
951          * generation. In that case be sure the cpu type is correctly
952          * manually setup otherwise it could trigger some nasty bugs.
953          */
954         BUG_ON(current_cpu_type() != c->cputype);
955
956         if (c->options & MIPS_CPU_FPU) {
957                 c->fpu_id = cpu_get_fpu_id();
958
959                 if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
960                     c->isa_level == MIPS_CPU_ISA_M32R2 ||
961                     c->isa_level == MIPS_CPU_ISA_M64R1 ||
962                     c->isa_level == MIPS_CPU_ISA_M64R2) {
963                         if (c->fpu_id & MIPS_FPIR_3D)
964                                 c->ases |= MIPS_ASE_MIPS3D;
965                 }
966         }
967
968         if (cpu_has_mips_r2)
969                 c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
970         else
971                 c->srsets = 1;
972 }
973
974 __cpuinit void cpu_report(void)
975 {
976         struct cpuinfo_mips *c = &current_cpu_data;
977
978         printk(KERN_INFO "CPU revision is: %08x (%s)\n",
979                c->processor_id, cpu_name_string());
980         if (c->options & MIPS_CPU_FPU)
981                 printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
982 }