git.oblomov.eu Git - linux-2.6/blob - arch/mips/kernel/cpu-probe.c

   1 /*
   2  * Processor capabilities determination functions.
   3  *
   4  * Copyright (C) xxxx  the Anonymous
   5  * Copyright (C) 2003, 2004  Maciej W. Rozycki
   6  * Copyright (C) 1994 - 2003 Ralf Baechle
   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/config.h>
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/stddef.h>
  19
  20 #include <asm/cpu.h>
  21 #include <asm/fpu.h>
  22 #include <asm/mipsregs.h>
  23 #include <asm/system.h>
  24
  25 /*
  26  * Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
  27  * the implementation of the "wait" feature differs between CPU families. This
  28  * points to the function that implements CPU specific wait.
  29  * The wait instruction stops the pipeline and reduces the power consumption of
  30  * the CPU very much.
  31  */
  32 void (*cpu_wait)(void) = NULL;
  33
  34 static void r3081_wait(void)
  35 {
  36         unsigned long cfg = read_c0_conf();
  37         write_c0_conf(cfg | R30XX_CONF_HALT);
  38 }
  39
  40 static void r39xx_wait(void)
  41 {
  42         unsigned long cfg = read_c0_conf();
  43         write_c0_conf(cfg | TX39_CONF_HALT);
  44 }
  45
  46 static void r4k_wait(void)
  47 {
  48         __asm__(".set\tmips3\n\t"
  49                 "wait\n\t"
  50                 ".set\tmips0");
  51 }
  52
  53 /* The Au1xxx wait is available only if using 32khz counter or
  54  * external timer source, but specifically not CP0 Counter. */
  55 int allow_au1k_wait;
  56
  57 static void au1k_wait(void)
  58 {
  59         /* using the wait instruction makes CP0 counter unusable */
  60         __asm__(".set mips3\n\t"
  61                 "cache 0x14, 0(%0)\n\t"
  62                 "cache 0x14, 32(%0)\n\t"
  63                 "sync\n\t"
  64                 "nop\n\t"
  65                 "wait\n\t"
  66                 "nop\n\t"
  67                 "nop\n\t"
  68                 "nop\n\t"
  69                 "nop\n\t"
  70                 ".set mips0\n\t"
  71                 : : "r" (au1k_wait));
  72 }
  73
  74 static int __initdata nowait = 0;
  75
  76 int __init wait_disable(char *s)
  77 {
  78         nowait = 1;
  79
  80         return 1;
  81 }
  82
  83 __setup("nowait", wait_disable);
  84
  85 static inline void check_wait(void)
  86 {
  87         struct cpuinfo_mips *c = &current_cpu_data;
  88
  89         printk("Checking for 'wait' instruction... ");
  90         if (nowait) {
  91                 printk (" disabled.\n");
  92                 return;
  93         }
  94
  95         switch (c->cputype) {
  96         case CPU_R3081:
  97         case CPU_R3081E:
  98                 cpu_wait = r3081_wait;
  99                 printk(" available.\n");
 100                 break;
 101         case CPU_TX3927:
 102                 cpu_wait = r39xx_wait;
 103                 printk(" available.\n");
 104                 break;
 105         case CPU_R4200:
 106 /*      case CPU_R4300: */
 107         case CPU_R4600:
 108         case CPU_R4640:
 109         case CPU_R4650:
 110         case CPU_R4700:
 111         case CPU_R5000:
 112         case CPU_NEVADA:
 113         case CPU_RM7000:
 114         case CPU_RM9000:
 115         case CPU_TX49XX:
 116         case CPU_4KC:
 117         case CPU_4KEC:
 118         case CPU_4KSC:
 119         case CPU_5KC:
 120 /*      case CPU_20KC:*/
 121         case CPU_24K:
 122         case CPU_25KF:
 123         case CPU_34K:
 124         case CPU_PR4450:
 125                 cpu_wait = r4k_wait;
 126                 printk(" available.\n");
 127                 break;
 128         case CPU_AU1000:
 129         case CPU_AU1100:
 130         case CPU_AU1500:
 131         case CPU_AU1550:
 132         case CPU_AU1200:
 133                 if (allow_au1k_wait) {
 134                         cpu_wait = au1k_wait;
 135                         printk(" available.\n");
 136                 } else
 137                         printk(" unavailable.\n");
 138                 break;
 139         default:
 140                 printk(" unavailable.\n");
 141                 break;
 142         }
 143 }
 144
 145 void __init check_bugs32(void)
 146 {
 147         check_wait();
 148 }
 149
 150 /*
 151  * Probe whether cpu has config register by trying to play with
 152  * alternate cache bit and see whether it matters.
 153  * It's used by cpu_probe to distinguish between R3000A and R3081.
 154  */
 155 static inline int cpu_has_confreg(void)
 156 {
 157 #ifdef CONFIG_CPU_R3000
 158         extern unsigned long r3k_cache_size(unsigned long);
 159         unsigned long size1, size2;
 160         unsigned long cfg = read_c0_conf();
 161
 162         size1 = r3k_cache_size(ST0_ISC);
 163         write_c0_conf(cfg ^ R30XX_CONF_AC);
 164         size2 = r3k_cache_size(ST0_ISC);
 165         write_c0_conf(cfg);
 166         return size1 != size2;
 167 #else
 168         return 0;
 169 #endif
 170 }
 171
 172 /*
 173  * Get the FPU Implementation/Revision.
 174  */
 175 static inline unsigned long cpu_get_fpu_id(void)
 176 {
 177         unsigned long tmp, fpu_id;
 178
 179         tmp = read_c0_status();
 180         __enable_fpu();
 181         fpu_id = read_32bit_cp1_register(CP1_REVISION);
 182         write_c0_status(tmp);
 183         return fpu_id;
 184 }
 185
 186 /*
 187  * Check the CPU has an FPU the official way.
 188  */
 189 static inline int __cpu_has_fpu(void)
 190 {
 191         return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
 192 }
 193
 194 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
 195                 | MIPS_CPU_COUNTER)
 196
 197 static inline void cpu_probe_legacy(struct cpuinfo_mips *c)
 198 {
 199         switch (c->processor_id & 0xff00) {
 200         case PRID_IMP_R2000:
 201                 c->cputype = CPU_R2000;
 202                 c->isa_level = MIPS_CPU_ISA_I;
 203                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 204                              MIPS_CPU_NOFPUEX;
 205                 if (__cpu_has_fpu())
 206                         c->options |= MIPS_CPU_FPU;
 207                 c->tlbsize = 64;
 208                 break;
 209         case PRID_IMP_R3000:
 210                 if ((c->processor_id & 0xff) == PRID_REV_R3000A)
 211                         if (cpu_has_confreg())
 212                                 c->cputype = CPU_R3081E;
 213                         else
 214                                 c->cputype = CPU_R3000A;
 215                 else
 216                         c->cputype = CPU_R3000;
 217                 c->isa_level = MIPS_CPU_ISA_I;
 218                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 219                              MIPS_CPU_NOFPUEX;
 220                 if (__cpu_has_fpu())
 221                         c->options |= MIPS_CPU_FPU;
 222                 c->tlbsize = 64;
 223                 break;
 224         case PRID_IMP_R4000:
 225                 if (read_c0_config() & CONF_SC) {
 226                         if ((c->processor_id & 0xff) >= PRID_REV_R4400)
 227                                 c->cputype = CPU_R4400PC;
 228                         else
 229                                 c->cputype = CPU_R4000PC;
 230                 } else {
 231                         if ((c->processor_id & 0xff) >= PRID_REV_R4400)
 232                                 c->cputype = CPU_R4400SC;
 233                         else
 234                                 c->cputype = CPU_R4000SC;
 235                 }
 236
 237                 c->isa_level = MIPS_CPU_ISA_III;
 238                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 239                              MIPS_CPU_WATCH | MIPS_CPU_VCE |
 240                              MIPS_CPU_LLSC;
 241                 c->tlbsize = 48;
 242                 break;
 243         case PRID_IMP_VR41XX:
 244                 switch (c->processor_id & 0xf0) {
 245                 case PRID_REV_VR4111:
 246                         c->cputype = CPU_VR4111;
 247                         break;
 248                 case PRID_REV_VR4121:
 249                         c->cputype = CPU_VR4121;
 250                         break;
 251                 case PRID_REV_VR4122:
 252                         if ((c->processor_id & 0xf) < 0x3)
 253                                 c->cputype = CPU_VR4122;
 254                         else
 255                                 c->cputype = CPU_VR4181A;
 256                         break;
 257                 case PRID_REV_VR4130:
 258                         if ((c->processor_id & 0xf) < 0x4)
 259                                 c->cputype = CPU_VR4131;
 260                         else
 261                                 c->cputype = CPU_VR4133;
 262                         break;
 263                 default:
 264                         printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
 265                         c->cputype = CPU_VR41XX;
 266                         break;
 267                 }
 268                 c->isa_level = MIPS_CPU_ISA_III;
 269                 c->options = R4K_OPTS;
 270                 c->tlbsize = 32;
 271                 break;
 272         case PRID_IMP_R4300:
 273                 c->cputype = CPU_R4300;
 274                 c->isa_level = MIPS_CPU_ISA_III;
 275                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 276                              MIPS_CPU_LLSC;
 277                 c->tlbsize = 32;
 278                 break;
 279         case PRID_IMP_R4600:
 280                 c->cputype = CPU_R4600;
 281                 c->isa_level = MIPS_CPU_ISA_III;
 282                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 283                              MIPS_CPU_LLSC;
 284                 c->tlbsize = 48;
 285                 break;
 286         #if 0
 287         case PRID_IMP_R4650:
 288                 /*
 289                  * This processor doesn't have an MMU, so it's not
 290                  * "real easy" to run Linux on it. It is left purely
 291                  * for documentation.  Commented out because it shares
 292                  * it's c0_prid id number with the TX3900.
 293                  */
 294                 c->cputype = CPU_R4650;
 295                 c->isa_level = MIPS_CPU_ISA_III;
 296                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
 297                 c->tlbsize = 48;
 298                 break;
 299         #endif
 300         case PRID_IMP_TX39:
 301                 c->isa_level = MIPS_CPU_ISA_I;
 302                 c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
 303
 304                 if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
 305                         c->cputype = CPU_TX3927;
 306                         c->tlbsize = 64;
 307                 } else {
 308                         switch (c->processor_id & 0xff) {
 309                         case PRID_REV_TX3912:
 310                                 c->cputype = CPU_TX3912;
 311                                 c->tlbsize = 32;
 312                                 break;
 313                         case PRID_REV_TX3922:
 314                                 c->cputype = CPU_TX3922;
 315                                 c->tlbsize = 64;
 316                                 break;
 317                         default:
 318                                 c->cputype = CPU_UNKNOWN;
 319                                 break;
 320                         }
 321                 }
 322                 break;
 323         case PRID_IMP_R4700:
 324                 c->cputype = CPU_R4700;
 325                 c->isa_level = MIPS_CPU_ISA_III;
 326                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 327                              MIPS_CPU_LLSC;
 328                 c->tlbsize = 48;
 329                 break;
 330         case PRID_IMP_TX49:
 331                 c->cputype = CPU_TX49XX;
 332                 c->isa_level = MIPS_CPU_ISA_III;
 333                 c->options = R4K_OPTS | MIPS_CPU_LLSC;
 334                 if (!(c->processor_id & 0x08))
 335                         c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
 336                 c->tlbsize = 48;
 337                 break;
 338         case PRID_IMP_R5000:
 339                 c->cputype = CPU_R5000;
 340                 c->isa_level = MIPS_CPU_ISA_IV;
 341                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 342                              MIPS_CPU_LLSC;
 343                 c->tlbsize = 48;
 344                 break;
 345         case PRID_IMP_R5432:
 346                 c->cputype = CPU_R5432;
 347                 c->isa_level = MIPS_CPU_ISA_IV;
 348                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 349                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
 350                 c->tlbsize = 48;
 351                 break;
 352         case PRID_IMP_R5500:
 353                 c->cputype = CPU_R5500;
 354                 c->isa_level = MIPS_CPU_ISA_IV;
 355                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 356                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
 357                 c->tlbsize = 48;
 358                 break;
 359         case PRID_IMP_NEVADA:
 360                 c->cputype = CPU_NEVADA;
 361                 c->isa_level = MIPS_CPU_ISA_IV;
 362                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 363                              MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
 364                 c->tlbsize = 48;
 365                 break;
 366         case PRID_IMP_R6000:
 367                 c->cputype = CPU_R6000;
 368                 c->isa_level = MIPS_CPU_ISA_II;
 369                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
 370                              MIPS_CPU_LLSC;
 371                 c->tlbsize = 32;
 372                 break;
 373         case PRID_IMP_R6000A:
 374                 c->cputype = CPU_R6000A;
 375                 c->isa_level = MIPS_CPU_ISA_II;
 376                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
 377                              MIPS_CPU_LLSC;
 378                 c->tlbsize = 32;
 379                 break;
 380         case PRID_IMP_RM7000:
 381                 c->cputype = CPU_RM7000;
 382                 c->isa_level = MIPS_CPU_ISA_IV;
 383                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 384                              MIPS_CPU_LLSC;
 385                 /*
 386                  * Undocumented RM7000:  Bit 29 in the info register of
 387                  * the RM7000 v2.0 indicates if the TLB has 48 or 64
 388                  * entries.
 389                  *
 390                  * 29      1 =>    64 entry JTLB
 391                  *         0 =>    48 entry JTLB
 392                  */
 393                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
 394                 break;
 395         case PRID_IMP_RM9000:
 396                 c->cputype = CPU_RM9000;
 397                 c->isa_level = MIPS_CPU_ISA_IV;
 398                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 399                              MIPS_CPU_LLSC;
 400                 /*
 401                  * Bit 29 in the info register of the RM9000
 402                  * indicates if the TLB has 48 or 64 entries.
 403                  *
 404                  * 29      1 =>    64 entry JTLB
 405                  *         0 =>    48 entry JTLB
 406                  */
 407                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
 408                 break;
 409         case PRID_IMP_R8000:
 410                 c->cputype = CPU_R8000;
 411                 c->isa_level = MIPS_CPU_ISA_IV;
 412                 c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
 413                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 414                              MIPS_CPU_LLSC;
 415                 c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
 416                 break;
 417         case PRID_IMP_R10000:
 418                 c->cputype = CPU_R10000;
 419                 c->isa_level = MIPS_CPU_ISA_IV;
 420                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
 421                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 422                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
 423                              MIPS_CPU_LLSC;
 424                 c->tlbsize = 64;
 425                 break;
 426         case PRID_IMP_R12000:
 427                 c->cputype = CPU_R12000;
 428                 c->isa_level = MIPS_CPU_ISA_IV;
 429                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
 430                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 431                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
 432                              MIPS_CPU_LLSC;
 433                 c->tlbsize = 64;
 434                 break;
 435         }
 436 }
 437
 438 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
 439 {
 440         unsigned int config0;
 441         int isa;
 442
 443         config0 = read_c0_config();
 444
 445         if (((config0 & MIPS_CONF_MT) >> 7) == 1)
 446                 c->options |= MIPS_CPU_TLB;
 447         isa = (config0 & MIPS_CONF_AT) >> 13;
 448         switch (isa) {
 449         case 0:
 450                 c->isa_level = MIPS_CPU_ISA_M32;
 451                 break;
 452         case 2:
 453                 c->isa_level = MIPS_CPU_ISA_M64;
 454                 break;
 455         default:
 456                 panic("Unsupported ISA type, cp0.config0.at: %d.", isa);
 457         }
 458
 459         return config0 & MIPS_CONF_M;
 460 }
 461
 462 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
 463 {
 464         unsigned int config1;
 465
 466         config1 = read_c0_config1();
 467
 468         if (config1 & MIPS_CONF1_MD)
 469                 c->ases |= MIPS_ASE_MDMX;
 470         if (config1 & MIPS_CONF1_WR)
 471                 c->options |= MIPS_CPU_WATCH;
 472         if (config1 & MIPS_CONF1_CA)
 473                 c->ases |= MIPS_ASE_MIPS16;
 474         if (config1 & MIPS_CONF1_EP)
 475                 c->options |= MIPS_CPU_EJTAG;
 476         if (config1 & MIPS_CONF1_FP) {
 477                 c->options |= MIPS_CPU_FPU;
 478                 c->options |= MIPS_CPU_32FPR;
 479         }
 480         if (cpu_has_tlb)
 481                 c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
 482
 483         return config1 & MIPS_CONF_M;
 484 }
 485
 486 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
 487 {
 488         unsigned int config2;
 489
 490         config2 = read_c0_config2();
 491
 492         if (config2 & MIPS_CONF2_SL)
 493                 c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
 494
 495         return config2 & MIPS_CONF_M;
 496 }
 497
 498 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
 499 {
 500         unsigned int config3;
 501
 502         config3 = read_c0_config3();
 503
 504         if (config3 & MIPS_CONF3_SM)
 505                 c->ases |= MIPS_ASE_SMARTMIPS;
 506         if (config3 & MIPS_CONF3_DSP)
 507                 c->ases |= MIPS_ASE_DSP;
 508         if (config3 & MIPS_CONF3_VINT)
 509                 c->options |= MIPS_CPU_VINT;
 510         if (config3 & MIPS_CONF3_VEIC)
 511                 c->options |= MIPS_CPU_VEIC;
 512         if (config3 & MIPS_CONF3_MT)
 513                 c->ases |= MIPS_ASE_MIPSMT;
 514
 515         return config3 & MIPS_CONF_M;
 516 }
 517
 518 static inline void decode_configs(struct cpuinfo_mips *c)
 519 {
 520         /* MIPS32 or MIPS64 compliant CPU.  */
 521         c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
 522                      MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
 523
 524         c->scache.flags = MIPS_CACHE_NOT_PRESENT;
 525
 526         /* Read Config registers.  */
 527         if (!decode_config0(c))
 528                 return;                 /* actually worth a panic() */
 529         if (!decode_config1(c))
 530                 return;
 531         if (!decode_config2(c))
 532                 return;
 533         if (!decode_config3(c))
 534                 return;
 535 }
 536
 537 static inline void cpu_probe_mips(struct cpuinfo_mips *c)
 538 {
 539         decode_configs(c);
 540         switch (c->processor_id & 0xff00) {
 541         case PRID_IMP_4KC:
 542                 c->cputype = CPU_4KC;
 543                 break;
 544         case PRID_IMP_4KEC:
 545                 c->cputype = CPU_4KEC;
 546                 break;
 547         case PRID_IMP_4KECR2:
 548                 c->cputype = CPU_4KEC;
 549                 break;
 550         case PRID_IMP_4KSC:
 551         case PRID_IMP_4KSD:
 552                 c->cputype = CPU_4KSC;
 553                 break;
 554         case PRID_IMP_5KC:
 555                 c->cputype = CPU_5KC;
 556                 break;
 557         case PRID_IMP_20KC:
 558                 c->cputype = CPU_20KC;
 559                 break;
 560         case PRID_IMP_24K:
 561         case PRID_IMP_24KE:
 562                 c->cputype = CPU_24K;
 563                 break;
 564         case PRID_IMP_25KF:
 565                 c->cputype = CPU_25KF;
 566                 /* Probe for L2 cache */
 567                 c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
 568                 break;
 569         case PRID_IMP_34K:
 570                 c->cputype = CPU_34K;
 571                 c->isa_level = MIPS_CPU_ISA_M32;
 572                 break;
 573         }
 574 }
 575
 576 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c)
 577 {
 578         decode_configs(c);
 579         switch (c->processor_id & 0xff00) {
 580         case PRID_IMP_AU1_REV1:
 581         case PRID_IMP_AU1_REV2:
 582                 switch ((c->processor_id >> 24) & 0xff) {
 583                 case 0:
 584                         c->cputype = CPU_AU1000;
 585                         break;
 586                 case 1:
 587                         c->cputype = CPU_AU1500;
 588                         break;
 589                 case 2:
 590                         c->cputype = CPU_AU1100;
 591                         break;
 592                 case 3:
 593                         c->cputype = CPU_AU1550;
 594                         break;
 595                 case 4:
 596                         c->cputype = CPU_AU1200;
 597                         break;
 598                 default:
 599                         panic("Unknown Au Core!");
 600                         break;
 601                 }
 602                 break;
 603         }
 604 }
 605
 606 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c)
 607 {
 608         decode_configs(c);
 609
 610         /*
 611          * For historical reasons the SB1 comes with it's own variant of
 612          * cache code which eventually will be folded into c-r4k.c.  Until
 613          * then we pretend it's got it's own cache architecture.
 614          */
 615         c->options &= ~MIPS_CPU_4K_CACHE;
 616         c->options |= MIPS_CPU_SB1_CACHE;
 617
 618         switch (c->processor_id & 0xff00) {
 619         case PRID_IMP_SB1:
 620                 c->cputype = CPU_SB1;
 621 #ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
 622                 /* FPU in pass1 is known to have issues. */
 623                 c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
 624 #endif
 625                 break;
 626         case PRID_IMP_SB1A:
 627                 c->cputype = CPU_SB1A;
 628                 break;
 629         }
 630 }
 631
 632 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c)
 633 {
 634         decode_configs(c);
 635         switch (c->processor_id & 0xff00) {
 636         case PRID_IMP_SR71000:
 637                 c->cputype = CPU_SR71000;
 638                 c->scache.ways = 8;
 639                 c->tlbsize = 64;
 640                 break;
 641         }
 642 }
 643
 644 static inline void cpu_probe_philips(struct cpuinfo_mips *c)
 645 {
 646         decode_configs(c);
 647         switch (c->processor_id & 0xff00) {
 648         case PRID_IMP_PR4450:
 649                 c->cputype = CPU_PR4450;
 650                 c->isa_level = MIPS_CPU_ISA_M32;
 651                 break;
 652         default:
 653                 panic("Unknown Philips Core!"); /* REVISIT: die? */
 654                 break;
 655         }
 656 }
 657
 658
 659 __init void cpu_probe(void)
 660 {
 661         struct cpuinfo_mips *c = &current_cpu_data;
 662
 663         c->processor_id = PRID_IMP_UNKNOWN;
 664         c->fpu_id       = FPIR_IMP_NONE;
 665         c->cputype      = CPU_UNKNOWN;
 666
 667         c->processor_id = read_c0_prid();
 668         switch (c->processor_id & 0xff0000) {
 669         case PRID_COMP_LEGACY:
 670                 cpu_probe_legacy(c);
 671                 break;
 672         case PRID_COMP_MIPS:
 673                 cpu_probe_mips(c);
 674                 break;
 675         case PRID_COMP_ALCHEMY:
 676                 cpu_probe_alchemy(c);
 677                 break;
 678         case PRID_COMP_SIBYTE:
 679                 cpu_probe_sibyte(c);
 680                 break;
 681         case PRID_COMP_SANDCRAFT:
 682                 cpu_probe_sandcraft(c);
 683                 break;
 684         case PRID_COMP_PHILIPS:
 685                 cpu_probe_philips(c);
 686                 break;
 687         default:
 688                 c->cputype = CPU_UNKNOWN;
 689         }
 690         if (c->options & MIPS_CPU_FPU) {
 691                 c->fpu_id = cpu_get_fpu_id();
 692
 693                 if (c->isa_level == MIPS_CPU_ISA_M32 ||
 694                     c->isa_level == MIPS_CPU_ISA_M64) {
 695                         if (c->fpu_id & MIPS_FPIR_3D)
 696                                 c->ases |= MIPS_ASE_MIPS3D;
 697                 }
 698         }
 699 }
 700
 701 __init void cpu_report(void)
 702 {
 703         struct cpuinfo_mips *c = &current_cpu_data;
 704
 705         printk("CPU revision is: %08x\n", c->processor_id);
 706         if (c->options & MIPS_CPU_FPU)
 707                 printk("FPU revision is: %08x\n", c->fpu_id);
 708 }