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/stddef.h>
  18
  19 #include <asm/bugs.h>
  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         local_irq_disable();
  43         if (!need_resched())
  44                 write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
  45         local_irq_enable();
  46 }
  47
  48 /*
  49  * There is a race when WAIT instruction executed with interrupt
  50  * enabled.
  51  * But it is implementation-dependent wheter the pipelie restarts when
  52  * a non-enabled interrupt is requested.
  53  */
  54 static void r4k_wait(void)
  55 {
  56         __asm__("       .set    mips3                   \n"
  57                 "       wait                            \n"
  58                 "       .set    mips0                   \n");
  59 }
  60
  61 /*
  62  * This variant is preferable as it allows testing need_resched and going to
  63  * sleep depending on the outcome atomically.  Unfortunately the "It is
  64  * implementation-dependent whether the pipeline restarts when a non-enabled
  65  * interrupt is requested" restriction in the MIPS32/MIPS64 architecture makes
  66  * using this version a gamble.
  67  */
  68 static void r4k_wait_irqoff(void)
  69 {
  70         local_irq_disable();
  71         if (!need_resched())
  72                 __asm__("       .set    mips3           \n"
  73                         "       wait                    \n"
  74                         "       .set    mips0           \n");
  75         local_irq_enable();
  76 }
  77
  78 /*
  79  * The RM7000 variant has to handle erratum 38.  The workaround is to not
  80  * have any pending stores when the WAIT instruction is executed.
  81  */
  82 static void rm7k_wait_irqoff(void)
  83 {
  84         local_irq_disable();
  85         if (!need_resched())
  86                 __asm__(
  87                 "       .set    push                                    \n"
  88                 "       .set    mips3                                   \n"
  89                 "       .set    noat                                    \n"
  90                 "       mfc0    $1, $12                                 \n"
  91                 "       sync                                            \n"
  92                 "       mtc0    $1, $12         # stalls until W stage  \n"
  93                 "       wait                                            \n"
  94                 "       mtc0    $1, $12         # stalls until W stage  \n"
  95                 "       .set    pop                                     \n");
  96         local_irq_enable();
  97 }
  98
  99 /* The Au1xxx wait is available only if using 32khz counter or
 100  * external timer source, but specifically not CP0 Counter. */
 101 int allow_au1k_wait;
 102
 103 static void au1k_wait(void)
 104 {
 105         /* using the wait instruction makes CP0 counter unusable */
 106         __asm__("       .set    mips3                   \n"
 107                 "       cache   0x14, 0(%0)             \n"
 108                 "       cache   0x14, 32(%0)            \n"
 109                 "       sync                            \n"
 110                 "       nop                             \n"
 111                 "       wait                            \n"
 112                 "       nop                             \n"
 113                 "       nop                             \n"
 114                 "       nop                             \n"
 115                 "       nop                             \n"
 116                 "       .set    mips0                   \n"
 117                 : : "r" (au1k_wait));
 118 }
 119
 120 static int __initdata nowait = 0;
 121
 122 static int __init wait_disable(char *s)
 123 {
 124         nowait = 1;
 125
 126         return 1;
 127 }
 128
 129 __setup("nowait", wait_disable);
 130
 131 static inline void check_wait(void)
 132 {
 133         struct cpuinfo_mips *c = &current_cpu_data;
 134
 135         if (nowait) {
 136                 printk("Wait instruction disabled.\n");
 137                 return;
 138         }
 139
 140         switch (c->cputype) {
 141         case CPU_R3081:
 142         case CPU_R3081E:
 143                 cpu_wait = r3081_wait;
 144                 break;
 145         case CPU_TX3927:
 146                 cpu_wait = r39xx_wait;
 147                 break;
 148         case CPU_R4200:
 149 /*      case CPU_R4300: */
 150         case CPU_R4600:
 151         case CPU_R4640:
 152         case CPU_R4650:
 153         case CPU_R4700:
 154         case CPU_R5000:
 155         case CPU_NEVADA:
 156         case CPU_4KC:
 157         case CPU_4KEC:
 158         case CPU_4KSC:
 159         case CPU_5KC:
 160         case CPU_25KF:
 161         case CPU_PR4450:
 162         case CPU_BCM3302:
 163                 cpu_wait = r4k_wait;
 164                 break;
 165
 166         case CPU_RM7000:
 167                 cpu_wait = rm7k_wait_irqoff;
 168                 break;
 169
 170         case CPU_24K:
 171         case CPU_34K:
 172         case CPU_1004K:
 173                 cpu_wait = r4k_wait;
 174                 if (read_c0_config7() & MIPS_CONF7_WII)
 175                         cpu_wait = r4k_wait_irqoff;
 176                 break;
 177
 178         case CPU_74K:
 179                 cpu_wait = r4k_wait;
 180                 if ((c->processor_id & 0xff) >= PRID_REV_ENCODE_332(2, 1, 0))
 181                         cpu_wait = r4k_wait_irqoff;
 182                 break;
 183
 184         case CPU_TX49XX:
 185                 cpu_wait = r4k_wait_irqoff;
 186                 break;
 187         case CPU_AU1000:
 188         case CPU_AU1100:
 189         case CPU_AU1500:
 190         case CPU_AU1550:
 191         case CPU_AU1200:
 192         case CPU_AU1210:
 193         case CPU_AU1250:
 194                 if (allow_au1k_wait)
 195                         cpu_wait = au1k_wait;
 196                 break;
 197         case CPU_20KC:
 198                 /*
 199                  * WAIT on Rev1.0 has E1, E2, E3 and E16.
 200                  * WAIT on Rev2.0 and Rev3.0 has E16.
 201                  * Rev3.1 WAIT is nop, why bother
 202                  */
 203                 if ((c->processor_id & 0xff) <= 0x64)
 204                         break;
 205
 206                 /*
 207                  * Another rev is incremeting c0_count at a reduced clock
 208                  * rate while in WAIT mode.  So we basically have the choice
 209                  * between using the cp0 timer as clocksource or avoiding
 210                  * the WAIT instruction.  Until more details are known,
 211                  * disable the use of WAIT for 20Kc entirely.
 212                    cpu_wait = r4k_wait;
 213                  */
 214                 break;
 215         case CPU_RM9000:
 216                 if ((c->processor_id & 0x00ff) >= 0x40)
 217                         cpu_wait = r4k_wait;
 218                 break;
 219         default:
 220                 break;
 221         }
 222 }
 223
 224 static inline void check_errata(void)
 225 {
 226         struct cpuinfo_mips *c = &current_cpu_data;
 227
 228         switch (c->cputype) {
 229         case CPU_34K:
 230                 /*
 231                  * Erratum "RPS May Cause Incorrect Instruction Execution"
 232                  * This code only handles VPE0, any SMP/SMTC/RTOS code
 233                  * making use of VPE1 will be responsable for that VPE.
 234                  */
 235                 if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
 236                         write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
 237                 break;
 238         default:
 239                 break;
 240         }
 241 }
 242
 243 void __init check_bugs32(void)
 244 {
 245         check_wait();
 246         check_errata();
 247 }
 248
 249 /*
 250  * Probe whether cpu has config register by trying to play with
 251  * alternate cache bit and see whether it matters.
 252  * It's used by cpu_probe to distinguish between R3000A and R3081.
 253  */
 254 static inline int cpu_has_confreg(void)
 255 {
 256 #ifdef CONFIG_CPU_R3000
 257         extern unsigned long r3k_cache_size(unsigned long);
 258         unsigned long size1, size2;
 259         unsigned long cfg = read_c0_conf();
 260
 261         size1 = r3k_cache_size(ST0_ISC);
 262         write_c0_conf(cfg ^ R30XX_CONF_AC);
 263         size2 = r3k_cache_size(ST0_ISC);
 264         write_c0_conf(cfg);
 265         return size1 != size2;
 266 #else
 267         return 0;
 268 #endif
 269 }
 270
 271 /*
 272  * Get the FPU Implementation/Revision.
 273  */
 274 static inline unsigned long cpu_get_fpu_id(void)
 275 {
 276         unsigned long tmp, fpu_id;
 277
 278         tmp = read_c0_status();
 279         __enable_fpu();
 280         fpu_id = read_32bit_cp1_register(CP1_REVISION);
 281         write_c0_status(tmp);
 282         return fpu_id;
 283 }
 284
 285 /*
 286  * Check the CPU has an FPU the official way.
 287  */
 288 static inline int __cpu_has_fpu(void)
 289 {
 290         return ((cpu_get_fpu_id() & 0xff00) != FPIR_IMP_NONE);
 291 }
 292
 293 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
 294                 | MIPS_CPU_COUNTER)
 295
 296 static inline void cpu_probe_legacy(struct cpuinfo_mips *c)
 297 {
 298         switch (c->processor_id & 0xff00) {
 299         case PRID_IMP_R2000:
 300                 c->cputype = CPU_R2000;
 301                 c->isa_level = MIPS_CPU_ISA_I;
 302                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 303                              MIPS_CPU_NOFPUEX;
 304                 if (__cpu_has_fpu())
 305                         c->options |= MIPS_CPU_FPU;
 306                 c->tlbsize = 64;
 307                 break;
 308         case PRID_IMP_R3000:
 309                 if ((c->processor_id & 0xff) == PRID_REV_R3000A)
 310                         if (cpu_has_confreg())
 311                                 c->cputype = CPU_R3081E;
 312                         else
 313                                 c->cputype = CPU_R3000A;
 314                 else
 315                         c->cputype = CPU_R3000;
 316                 c->isa_level = MIPS_CPU_ISA_I;
 317                 c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 318                              MIPS_CPU_NOFPUEX;
 319                 if (__cpu_has_fpu())
 320                         c->options |= MIPS_CPU_FPU;
 321                 c->tlbsize = 64;
 322                 break;
 323         case PRID_IMP_R4000:
 324                 if (read_c0_config() & CONF_SC) {
 325                         if ((c->processor_id & 0xff) >= PRID_REV_R4400)
 326                                 c->cputype = CPU_R4400PC;
 327                         else
 328                                 c->cputype = CPU_R4000PC;
 329                 } else {
 330                         if ((c->processor_id & 0xff) >= PRID_REV_R4400)
 331                                 c->cputype = CPU_R4400SC;
 332                         else
 333                                 c->cputype = CPU_R4000SC;
 334                 }
 335
 336                 c->isa_level = MIPS_CPU_ISA_III;
 337                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 338                              MIPS_CPU_WATCH | MIPS_CPU_VCE |
 339                              MIPS_CPU_LLSC;
 340                 c->tlbsize = 48;
 341                 break;
 342         case PRID_IMP_VR41XX:
 343                 switch (c->processor_id & 0xf0) {
 344                 case PRID_REV_VR4111:
 345                         c->cputype = CPU_VR4111;
 346                         break;
 347                 case PRID_REV_VR4121:
 348                         c->cputype = CPU_VR4121;
 349                         break;
 350                 case PRID_REV_VR4122:
 351                         if ((c->processor_id & 0xf) < 0x3)
 352                                 c->cputype = CPU_VR4122;
 353                         else
 354                                 c->cputype = CPU_VR4181A;
 355                         break;
 356                 case PRID_REV_VR4130:
 357                         if ((c->processor_id & 0xf) < 0x4)
 358                                 c->cputype = CPU_VR4131;
 359                         else
 360                                 c->cputype = CPU_VR4133;
 361                         break;
 362                 default:
 363                         printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
 364                         c->cputype = CPU_VR41XX;
 365                         break;
 366                 }
 367                 c->isa_level = MIPS_CPU_ISA_III;
 368                 c->options = R4K_OPTS;
 369                 c->tlbsize = 32;
 370                 break;
 371         case PRID_IMP_R4300:
 372                 c->cputype = CPU_R4300;
 373                 c->isa_level = MIPS_CPU_ISA_III;
 374                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 375                              MIPS_CPU_LLSC;
 376                 c->tlbsize = 32;
 377                 break;
 378         case PRID_IMP_R4600:
 379                 c->cputype = CPU_R4600;
 380                 c->isa_level = MIPS_CPU_ISA_III;
 381                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 382                              MIPS_CPU_LLSC;
 383                 c->tlbsize = 48;
 384                 break;
 385         #if 0
 386         case PRID_IMP_R4650:
 387                 /*
 388                  * This processor doesn't have an MMU, so it's not
 389                  * "real easy" to run Linux on it. It is left purely
 390                  * for documentation.  Commented out because it shares
 391                  * it's c0_prid id number with the TX3900.
 392                  */
 393                 c->cputype = CPU_R4650;
 394                 c->isa_level = MIPS_CPU_ISA_III;
 395                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
 396                 c->tlbsize = 48;
 397                 break;
 398         #endif
 399         case PRID_IMP_TX39:
 400                 c->isa_level = MIPS_CPU_ISA_I;
 401                 c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
 402
 403                 if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
 404                         c->cputype = CPU_TX3927;
 405                         c->tlbsize = 64;
 406                 } else {
 407                         switch (c->processor_id & 0xff) {
 408                         case PRID_REV_TX3912:
 409                                 c->cputype = CPU_TX3912;
 410                                 c->tlbsize = 32;
 411                                 break;
 412                         case PRID_REV_TX3922:
 413                                 c->cputype = CPU_TX3922;
 414                                 c->tlbsize = 64;
 415                                 break;
 416                         default:
 417                                 c->cputype = CPU_UNKNOWN;
 418                                 break;
 419                         }
 420                 }
 421                 break;
 422         case PRID_IMP_R4700:
 423                 c->cputype = CPU_R4700;
 424                 c->isa_level = MIPS_CPU_ISA_III;
 425                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 426                              MIPS_CPU_LLSC;
 427                 c->tlbsize = 48;
 428                 break;
 429         case PRID_IMP_TX49:
 430                 c->cputype = CPU_TX49XX;
 431                 c->isa_level = MIPS_CPU_ISA_III;
 432                 c->options = R4K_OPTS | MIPS_CPU_LLSC;
 433                 if (!(c->processor_id & 0x08))
 434                         c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
 435                 c->tlbsize = 48;
 436                 break;
 437         case PRID_IMP_R5000:
 438                 c->cputype = CPU_R5000;
 439                 c->isa_level = MIPS_CPU_ISA_IV;
 440                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 441                              MIPS_CPU_LLSC;
 442                 c->tlbsize = 48;
 443                 break;
 444         case PRID_IMP_R5432:
 445                 c->cputype = CPU_R5432;
 446                 c->isa_level = MIPS_CPU_ISA_IV;
 447                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 448                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
 449                 c->tlbsize = 48;
 450                 break;
 451         case PRID_IMP_R5500:
 452                 c->cputype = CPU_R5500;
 453                 c->isa_level = MIPS_CPU_ISA_IV;
 454                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 455                              MIPS_CPU_WATCH | MIPS_CPU_LLSC;
 456                 c->tlbsize = 48;
 457                 break;
 458         case PRID_IMP_NEVADA:
 459                 c->cputype = CPU_NEVADA;
 460                 c->isa_level = MIPS_CPU_ISA_IV;
 461                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 462                              MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
 463                 c->tlbsize = 48;
 464                 break;
 465         case PRID_IMP_R6000:
 466                 c->cputype = CPU_R6000;
 467                 c->isa_level = MIPS_CPU_ISA_II;
 468                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
 469                              MIPS_CPU_LLSC;
 470                 c->tlbsize = 32;
 471                 break;
 472         case PRID_IMP_R6000A:
 473                 c->cputype = CPU_R6000A;
 474                 c->isa_level = MIPS_CPU_ISA_II;
 475                 c->options = MIPS_CPU_TLB | MIPS_CPU_FPU |
 476                              MIPS_CPU_LLSC;
 477                 c->tlbsize = 32;
 478                 break;
 479         case PRID_IMP_RM7000:
 480                 c->cputype = CPU_RM7000;
 481                 c->isa_level = MIPS_CPU_ISA_IV;
 482                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 483                              MIPS_CPU_LLSC;
 484                 /*
 485                  * Undocumented RM7000:  Bit 29 in the info register of
 486                  * the RM7000 v2.0 indicates if the TLB has 48 or 64
 487                  * entries.
 488                  *
 489                  * 29      1 =>    64 entry JTLB
 490                  *         0 =>    48 entry JTLB
 491                  */
 492                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
 493                 break;
 494         case PRID_IMP_RM9000:
 495                 c->cputype = CPU_RM9000;
 496                 c->isa_level = MIPS_CPU_ISA_IV;
 497                 c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
 498                              MIPS_CPU_LLSC;
 499                 /*
 500                  * Bit 29 in the info register of the RM9000
 501                  * indicates if the TLB has 48 or 64 entries.
 502                  *
 503                  * 29      1 =>    64 entry JTLB
 504                  *         0 =>    48 entry JTLB
 505                  */
 506                 c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
 507                 break;
 508         case PRID_IMP_R8000:
 509                 c->cputype = CPU_R8000;
 510                 c->isa_level = MIPS_CPU_ISA_IV;
 511                 c->options = MIPS_CPU_TLB | MIPS_CPU_4KEX |
 512                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 513                              MIPS_CPU_LLSC;
 514                 c->tlbsize = 384;      /* has weird TLB: 3-way x 128 */
 515                 break;
 516         case PRID_IMP_R10000:
 517                 c->cputype = CPU_R10000;
 518                 c->isa_level = MIPS_CPU_ISA_IV;
 519                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
 520                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 521                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
 522                              MIPS_CPU_LLSC;
 523                 c->tlbsize = 64;
 524                 break;
 525         case PRID_IMP_R12000:
 526                 c->cputype = CPU_R12000;
 527                 c->isa_level = MIPS_CPU_ISA_IV;
 528                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
 529                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 530                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
 531                              MIPS_CPU_LLSC;
 532                 c->tlbsize = 64;
 533                 break;
 534         case PRID_IMP_R14000:
 535                 c->cputype = CPU_R14000;
 536                 c->isa_level = MIPS_CPU_ISA_IV;
 537                 c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
 538                              MIPS_CPU_FPU | MIPS_CPU_32FPR |
 539                              MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
 540                              MIPS_CPU_LLSC;
 541                 c->tlbsize = 64;
 542                 break;
 543         case PRID_IMP_LOONGSON2:
 544                 c->cputype = CPU_LOONGSON2;
 545                 c->isa_level = MIPS_CPU_ISA_III;
 546                 c->options = R4K_OPTS |
 547                              MIPS_CPU_FPU | MIPS_CPU_LLSC |
 548                              MIPS_CPU_32FPR;
 549                 c->tlbsize = 64;
 550                 break;
 551         }
 552 }
 553
 554 static char unknown_isa[] __cpuinitdata = KERN_ERR \
 555         "Unsupported ISA type, c0.config0: %d.";
 556
 557 static inline unsigned int decode_config0(struct cpuinfo_mips *c)
 558 {
 559         unsigned int config0;
 560         int isa;
 561
 562         config0 = read_c0_config();
 563
 564         if (((config0 & MIPS_CONF_MT) >> 7) == 1)
 565                 c->options |= MIPS_CPU_TLB;
 566         isa = (config0 & MIPS_CONF_AT) >> 13;
 567         switch (isa) {
 568         case 0:
 569                 switch ((config0 & MIPS_CONF_AR) >> 10) {
 570                 case 0:
 571                         c->isa_level = MIPS_CPU_ISA_M32R1;
 572                         break;
 573                 case 1:
 574                         c->isa_level = MIPS_CPU_ISA_M32R2;
 575                         break;
 576                 default:
 577                         goto unknown;
 578                 }
 579                 break;
 580         case 2:
 581                 switch ((config0 & MIPS_CONF_AR) >> 10) {
 582                 case 0:
 583                         c->isa_level = MIPS_CPU_ISA_M64R1;
 584                         break;
 585                 case 1:
 586                         c->isa_level = MIPS_CPU_ISA_M64R2;
 587                         break;
 588                 default:
 589                         goto unknown;
 590                 }
 591                 break;
 592         default:
 593                 goto unknown;
 594         }
 595
 596         return config0 & MIPS_CONF_M;
 597
 598 unknown:
 599         panic(unknown_isa, config0);
 600 }
 601
 602 static inline unsigned int decode_config1(struct cpuinfo_mips *c)
 603 {
 604         unsigned int config1;
 605
 606         config1 = read_c0_config1();
 607
 608         if (config1 & MIPS_CONF1_MD)
 609                 c->ases |= MIPS_ASE_MDMX;
 610         if (config1 & MIPS_CONF1_WR)
 611                 c->options |= MIPS_CPU_WATCH;
 612         if (config1 & MIPS_CONF1_CA)
 613                 c->ases |= MIPS_ASE_MIPS16;
 614         if (config1 & MIPS_CONF1_EP)
 615                 c->options |= MIPS_CPU_EJTAG;
 616         if (config1 & MIPS_CONF1_FP) {
 617                 c->options |= MIPS_CPU_FPU;
 618                 c->options |= MIPS_CPU_32FPR;
 619         }
 620         if (cpu_has_tlb)
 621                 c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
 622
 623         return config1 & MIPS_CONF_M;
 624 }
 625
 626 static inline unsigned int decode_config2(struct cpuinfo_mips *c)
 627 {
 628         unsigned int config2;
 629
 630         config2 = read_c0_config2();
 631
 632         if (config2 & MIPS_CONF2_SL)
 633                 c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
 634
 635         return config2 & MIPS_CONF_M;
 636 }
 637
 638 static inline unsigned int decode_config3(struct cpuinfo_mips *c)
 639 {
 640         unsigned int config3;
 641
 642         config3 = read_c0_config3();
 643
 644         if (config3 & MIPS_CONF3_SM)
 645                 c->ases |= MIPS_ASE_SMARTMIPS;
 646         if (config3 & MIPS_CONF3_DSP)
 647                 c->ases |= MIPS_ASE_DSP;
 648         if (config3 & MIPS_CONF3_VINT)
 649                 c->options |= MIPS_CPU_VINT;
 650         if (config3 & MIPS_CONF3_VEIC)
 651                 c->options |= MIPS_CPU_VEIC;
 652         if (config3 & MIPS_CONF3_MT)
 653                 c->ases |= MIPS_ASE_MIPSMT;
 654         if (config3 & MIPS_CONF3_ULRI)
 655                 c->options |= MIPS_CPU_ULRI;
 656
 657         return config3 & MIPS_CONF_M;
 658 }
 659
 660 static void __cpuinit decode_configs(struct cpuinfo_mips *c)
 661 {
 662         /* MIPS32 or MIPS64 compliant CPU.  */
 663         c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
 664                      MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
 665
 666         c->scache.flags = MIPS_CACHE_NOT_PRESENT;
 667
 668         /* Read Config registers.  */
 669         if (!decode_config0(c))
 670                 return;                 /* actually worth a panic() */
 671         if (!decode_config1(c))
 672                 return;
 673         if (!decode_config2(c))
 674                 return;
 675         if (!decode_config3(c))
 676                 return;
 677 }
 678
 679 #ifdef CONFIG_CPU_MIPSR2
 680 extern void spram_config(void);
 681 #else
 682 static inline void spram_config(void) {}
 683 #endif
 684
 685 static inline void cpu_probe_mips(struct cpuinfo_mips *c)
 686 {
 687         decode_configs(c);
 688         switch (c->processor_id & 0xff00) {
 689         case PRID_IMP_4KC:
 690                 c->cputype = CPU_4KC;
 691                 break;
 692         case PRID_IMP_4KEC:
 693                 c->cputype = CPU_4KEC;
 694                 break;
 695         case PRID_IMP_4KECR2:
 696                 c->cputype = CPU_4KEC;
 697                 break;
 698         case PRID_IMP_4KSC:
 699         case PRID_IMP_4KSD:
 700                 c->cputype = CPU_4KSC;
 701                 break;
 702         case PRID_IMP_5KC:
 703                 c->cputype = CPU_5KC;
 704                 break;
 705         case PRID_IMP_20KC:
 706                 c->cputype = CPU_20KC;
 707                 break;
 708         case PRID_IMP_24K:
 709         case PRID_IMP_24KE:
 710                 c->cputype = CPU_24K;
 711                 break;
 712         case PRID_IMP_25KF:
 713                 c->cputype = CPU_25KF;
 714                 break;
 715         case PRID_IMP_34K:
 716                 c->cputype = CPU_34K;
 717                 break;
 718         case PRID_IMP_74K:
 719                 c->cputype = CPU_74K;
 720                 break;
 721         case PRID_IMP_1004K:
 722                 c->cputype = CPU_1004K;
 723                 break;
 724         }
 725
 726         spram_config();
 727 }
 728
 729 static inline void cpu_probe_alchemy(struct cpuinfo_mips *c)
 730 {
 731         decode_configs(c);
 732         switch (c->processor_id & 0xff00) {
 733         case PRID_IMP_AU1_REV1:
 734         case PRID_IMP_AU1_REV2:
 735                 switch ((c->processor_id >> 24) & 0xff) {
 736                 case 0:
 737                         c->cputype = CPU_AU1000;
 738                         break;
 739                 case 1:
 740                         c->cputype = CPU_AU1500;
 741                         break;
 742                 case 2:
 743                         c->cputype = CPU_AU1100;
 744                         break;
 745                 case 3:
 746                         c->cputype = CPU_AU1550;
 747                         break;
 748                 case 4:
 749                         c->cputype = CPU_AU1200;
 750                         if (2 == (c->processor_id & 0xff))
 751                                 c->cputype = CPU_AU1250;
 752                         break;
 753                 case 5:
 754                         c->cputype = CPU_AU1210;
 755                         break;
 756                 default:
 757                         panic("Unknown Au Core!");
 758                         break;
 759                 }
 760                 break;
 761         }
 762 }
 763
 764 static inline void cpu_probe_sibyte(struct cpuinfo_mips *c)
 765 {
 766         decode_configs(c);
 767
 768         switch (c->processor_id & 0xff00) {
 769         case PRID_IMP_SB1:
 770                 c->cputype = CPU_SB1;
 771                 /* FPU in pass1 is known to have issues. */
 772                 if ((c->processor_id & 0xff) < 0x02)
 773                         c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
 774                 break;
 775         case PRID_IMP_SB1A:
 776                 c->cputype = CPU_SB1A;
 777                 break;
 778         }
 779 }
 780
 781 static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c)
 782 {
 783         decode_configs(c);
 784         switch (c->processor_id & 0xff00) {
 785         case PRID_IMP_SR71000:
 786                 c->cputype = CPU_SR71000;
 787                 c->scache.ways = 8;
 788                 c->tlbsize = 64;
 789                 break;
 790         }
 791 }
 792
 793 static inline void cpu_probe_nxp(struct cpuinfo_mips *c)
 794 {
 795         decode_configs(c);
 796         switch (c->processor_id & 0xff00) {
 797         case PRID_IMP_PR4450:
 798                 c->cputype = CPU_PR4450;
 799                 c->isa_level = MIPS_CPU_ISA_M32R1;
 800                 break;
 801         default:
 802                 panic("Unknown NXP Core!"); /* REVISIT: die? */
 803                 break;
 804         }
 805 }
 806
 807
 808 static inline void cpu_probe_broadcom(struct cpuinfo_mips *c)
 809 {
 810         decode_configs(c);
 811         switch (c->processor_id & 0xff00) {
 812         case PRID_IMP_BCM3302:
 813                 c->cputype = CPU_BCM3302;
 814                 break;
 815         case PRID_IMP_BCM4710:
 816                 c->cputype = CPU_BCM4710;
 817                 break;
 818         default:
 819                 c->cputype = CPU_UNKNOWN;
 820                 break;
 821         }
 822 }
 823
 824 const char *__cpu_name[NR_CPUS];
 825
 826 /*
 827  * Name a CPU
 828  */
 829 static __cpuinit const char *cpu_to_name(struct cpuinfo_mips *c)
 830 {
 831         const char *name = NULL;
 832
 833         switch (c->cputype) {
 834         case CPU_UNKNOWN:       name = "unknown"; break;
 835         case CPU_R2000:         name = "R2000"; break;
 836         case CPU_R3000:         name = "R3000"; break;
 837         case CPU_R3000A:        name = "R3000A"; break;
 838         case CPU_R3041:         name = "R3041"; break;
 839         case CPU_R3051:         name = "R3051"; break;
 840         case CPU_R3052:         name = "R3052"; break;
 841         case CPU_R3081:         name = "R3081"; break;
 842         case CPU_R3081E:        name = "R3081E"; break;
 843         case CPU_R4000PC:       name = "R4000PC"; break;
 844         case CPU_R4000SC:       name = "R4000SC"; break;
 845         case CPU_R4000MC:       name = "R4000MC"; break;
 846         case CPU_R4200:         name = "R4200"; break;
 847         case CPU_R4400PC:       name = "R4400PC"; break;
 848         case CPU_R4400SC:       name = "R4400SC"; break;
 849         case CPU_R4400MC:       name = "R4400MC"; break;
 850         case CPU_R4600:         name = "R4600"; break;
 851         case CPU_R6000:         name = "R6000"; break;
 852         case CPU_R6000A:        name = "R6000A"; break;
 853         case CPU_R8000:         name = "R8000"; break;
 854         case CPU_R10000:        name = "R10000"; break;
 855         case CPU_R12000:        name = "R12000"; break;
 856         case CPU_R14000:        name = "R14000"; break;
 857         case CPU_R4300:         name = "R4300"; break;
 858         case CPU_R4650:         name = "R4650"; break;
 859         case CPU_R4700:         name = "R4700"; break;
 860         case CPU_R5000:         name = "R5000"; break;
 861         case CPU_R5000A:        name = "R5000A"; break;
 862         case CPU_R4640:         name = "R4640"; break;
 863         case CPU_NEVADA:        name = "Nevada"; break;
 864         case CPU_RM7000:        name = "RM7000"; break;
 865         case CPU_RM9000:        name = "RM9000"; break;
 866         case CPU_R5432:         name = "R5432"; break;
 867         case CPU_4KC:           name = "MIPS 4Kc"; break;
 868         case CPU_5KC:           name = "MIPS 5Kc"; break;
 869         case CPU_R4310:         name = "R4310"; break;
 870         case CPU_SB1:           name = "SiByte SB1"; break;
 871         case CPU_SB1A:          name = "SiByte SB1A"; break;
 872         case CPU_TX3912:        name = "TX3912"; break;
 873         case CPU_TX3922:        name = "TX3922"; break;
 874         case CPU_TX3927:        name = "TX3927"; break;
 875         case CPU_AU1000:        name = "Au1000"; break;
 876         case CPU_AU1500:        name = "Au1500"; break;
 877         case CPU_AU1100:        name = "Au1100"; break;
 878         case CPU_AU1550:        name = "Au1550"; break;
 879         case CPU_AU1200:        name = "Au1200"; break;
 880         case CPU_AU1210:        name = "Au1210"; break;
 881         case CPU_AU1250:        name = "Au1250"; break;
 882         case CPU_4KEC:          name = "MIPS 4KEc"; break;
 883         case CPU_4KSC:          name = "MIPS 4KSc"; break;
 884         case CPU_VR41XX:        name = "NEC Vr41xx"; break;
 885         case CPU_R5500:         name = "R5500"; break;
 886         case CPU_TX49XX:        name = "TX49xx"; break;
 887         case CPU_20KC:          name = "MIPS 20Kc"; break;
 888         case CPU_24K:           name = "MIPS 24K"; break;
 889         case CPU_25KF:          name = "MIPS 25Kf"; break;
 890         case CPU_34K:           name = "MIPS 34K"; break;
 891         case CPU_1004K:         name = "MIPS 1004K"; break;
 892         case CPU_74K:           name = "MIPS 74K"; break;
 893         case CPU_VR4111:        name = "NEC VR4111"; break;
 894         case CPU_VR4121:        name = "NEC VR4121"; break;
 895         case CPU_VR4122:        name = "NEC VR4122"; break;
 896         case CPU_VR4131:        name = "NEC VR4131"; break;
 897         case CPU_VR4133:        name = "NEC VR4133"; break;
 898         case CPU_VR4181:        name = "NEC VR4181"; break;
 899         case CPU_VR4181A:       name = "NEC VR4181A"; break;
 900         case CPU_SR71000:       name = "Sandcraft SR71000"; break;
 901         case CPU_BCM3302:       name = "Broadcom BCM3302"; break;
 902         case CPU_BCM4710:       name = "Broadcom BCM4710"; break;
 903         case CPU_PR4450:        name = "Philips PR4450"; break;
 904         case CPU_LOONGSON2:     name = "ICT Loongson-2"; break;
 905         default:
 906                 BUG();
 907         }
 908
 909         return name;
 910 }
 911
 912 __cpuinit void cpu_probe(void)
 913 {
 914         struct cpuinfo_mips *c = &current_cpu_data;
 915         unsigned int cpu = smp_processor_id();
 916
 917         c->processor_id = PRID_IMP_UNKNOWN;
 918         c->fpu_id       = FPIR_IMP_NONE;
 919         c->cputype      = CPU_UNKNOWN;
 920
 921         c->processor_id = read_c0_prid();
 922         switch (c->processor_id & 0xff0000) {
 923         case PRID_COMP_LEGACY:
 924                 cpu_probe_legacy(c);
 925                 break;
 926         case PRID_COMP_MIPS:
 927                 cpu_probe_mips(c);
 928                 break;
 929         case PRID_COMP_ALCHEMY:
 930                 cpu_probe_alchemy(c);
 931                 break;
 932         case PRID_COMP_SIBYTE:
 933                 cpu_probe_sibyte(c);
 934                 break;
 935         case PRID_COMP_BROADCOM:
 936                 cpu_probe_broadcom(c);
 937                 break;
 938         case PRID_COMP_SANDCRAFT:
 939                 cpu_probe_sandcraft(c);
 940                 break;
 941         case PRID_COMP_NXP:
 942                 cpu_probe_nxp(c);
 943                 break;
 944         default:
 945                 c->cputype = CPU_UNKNOWN;
 946         }
 947
 948         /*
 949          * Platform code can force the cpu type to optimize code
 950          * generation. In that case be sure the cpu type is correctly
 951          * manually setup otherwise it could trigger some nasty bugs.
 952          */
 953         BUG_ON(current_cpu_type() != c->cputype);
 954
 955         if (c->options & MIPS_CPU_FPU) {
 956                 c->fpu_id = cpu_get_fpu_id();
 957
 958                 if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
 959                     c->isa_level == MIPS_CPU_ISA_M32R2 ||
 960                     c->isa_level == MIPS_CPU_ISA_M64R1 ||
 961                     c->isa_level == MIPS_CPU_ISA_M64R2) {
 962                         if (c->fpu_id & MIPS_FPIR_3D)
 963                                 c->ases |= MIPS_ASE_MIPS3D;
 964                 }
 965         }
 966
 967         __cpu_name[cpu] = cpu_to_name(c);
 968
 969         if (cpu_has_mips_r2)
 970                 c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
 971         else
 972                 c->srsets = 1;
 973 }
 974
 975 __cpuinit void cpu_report(void)
 976 {
 977         struct cpuinfo_mips *c = &current_cpu_data;
 978
 979         printk(KERN_INFO "CPU revision is: %08x (%s)\n",
 980                c->processor_id, cpu_name_string());
 981         if (c->options & MIPS_CPU_FPU)
 982                 printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
 983 }