git.oblomov.eu Git - linux-2.6/blob - arch/mips/mm/c-r4k.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   7  * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle (ralf@gnu.org)
   8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   9  */
  10 #include <linux/hardirq.h>
  11 #include <linux/init.h>
  12 #include <linux/highmem.h>
  13 #include <linux/kernel.h>
  14 #include <linux/linkage.h>
  15 #include <linux/sched.h>
  16 #include <linux/mm.h>
  17 #include <linux/module.h>
  18 #include <linux/bitops.h>
  19
  20 #include <asm/bcache.h>
  21 #include <asm/bootinfo.h>
  22 #include <asm/cache.h>
  23 #include <asm/cacheops.h>
  24 #include <asm/cpu.h>
  25 #include <asm/cpu-features.h>
  26 #include <asm/io.h>
  27 #include <asm/page.h>
  28 #include <asm/pgtable.h>
  29 #include <asm/r4kcache.h>
  30 #include <asm/sections.h>
  31 #include <asm/system.h>
  32 #include <asm/mmu_context.h>
  33 #include <asm/war.h>
  34 #include <asm/cacheflush.h> /* for run_uncached() */
  35
  36
  37 /*
  38  * Special Variant of smp_call_function for use by cache functions:
  39  *
  40  *  o No return value
  41  *  o collapses to normal function call on UP kernels
  42  *  o collapses to normal function call on systems with a single shared
  43  *    primary cache.
  44  */
  45 static inline void r4k_on_each_cpu(void (*func) (void *info), void *info,
  46                                    int wait)
  47 {
  48         preempt_disable();
  49
  50 #if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
  51         smp_call_function(func, info, wait);
  52 #endif
  53         func(info);
  54         preempt_enable();
  55 }
  56
  57 #if defined(CONFIG_MIPS_CMP)
  58 #define cpu_has_safe_index_cacheops 0
  59 #else
  60 #define cpu_has_safe_index_cacheops 1
  61 #endif
  62
  63 /*
  64  * Must die.
  65  */
  66 static unsigned long icache_size __read_mostly;
  67 static unsigned long dcache_size __read_mostly;
  68 static unsigned long scache_size __read_mostly;
  69
  70 /*
  71  * Dummy cache handling routines for machines without boardcaches
  72  */
  73 static void cache_noop(void) {}
  74
  75 static struct bcache_ops no_sc_ops = {
  76         .bc_enable = (void *)cache_noop,
  77         .bc_disable = (void *)cache_noop,
  78         .bc_wback_inv = (void *)cache_noop,
  79         .bc_inv = (void *)cache_noop
  80 };
  81
  82 struct bcache_ops *bcops = &no_sc_ops;
  83
  84 #define cpu_is_r4600_v1_x()     ((read_c0_prid() & 0xfffffff0) == 0x00002010)
  85 #define cpu_is_r4600_v2_x()     ((read_c0_prid() & 0xfffffff0) == 0x00002020)
  86
  87 #define R4600_HIT_CACHEOP_WAR_IMPL                                      \
  88 do {                                                                    \
  89         if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())            \
  90                 *(volatile unsigned long *)CKSEG1;                      \
  91         if (R4600_V1_HIT_CACHEOP_WAR)                                   \
  92                 __asm__ __volatile__("nop;nop;nop;nop");                \
  93 } while (0)
  94
  95 static void (*r4k_blast_dcache_page)(unsigned long addr);
  96
  97 static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
  98 {
  99         R4600_HIT_CACHEOP_WAR_IMPL;
 100         blast_dcache32_page(addr);
 101 }
 102
 103 static void __cpuinit r4k_blast_dcache_page_setup(void)
 104 {
 105         unsigned long  dc_lsize = cpu_dcache_line_size();
 106
 107         if (dc_lsize == 0)
 108                 r4k_blast_dcache_page = (void *)cache_noop;
 109         else if (dc_lsize == 16)
 110                 r4k_blast_dcache_page = blast_dcache16_page;
 111         else if (dc_lsize == 32)
 112                 r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
 113 }
 114
 115 static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);
 116
 117 static void __cpuinit r4k_blast_dcache_page_indexed_setup(void)
 118 {
 119         unsigned long dc_lsize = cpu_dcache_line_size();
 120
 121         if (dc_lsize == 0)
 122                 r4k_blast_dcache_page_indexed = (void *)cache_noop;
 123         else if (dc_lsize == 16)
 124                 r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
 125         else if (dc_lsize == 32)
 126                 r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
 127 }
 128
 129 static void (* r4k_blast_dcache)(void);
 130
 131 static void __cpuinit r4k_blast_dcache_setup(void)
 132 {
 133         unsigned long dc_lsize = cpu_dcache_line_size();
 134
 135         if (dc_lsize == 0)
 136                 r4k_blast_dcache = (void *)cache_noop;
 137         else if (dc_lsize == 16)
 138                 r4k_blast_dcache = blast_dcache16;
 139         else if (dc_lsize == 32)
 140                 r4k_blast_dcache = blast_dcache32;
 141 }
 142
 143 /* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
 144 #define JUMP_TO_ALIGN(order) \
 145         __asm__ __volatile__( \
 146                 "b\t1f\n\t" \
 147                 ".align\t" #order "\n\t" \
 148                 "1:\n\t" \
 149                 )
 150 #define CACHE32_UNROLL32_ALIGN  JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
 151 #define CACHE32_UNROLL32_ALIGN2 JUMP_TO_ALIGN(11)
 152
 153 static inline void blast_r4600_v1_icache32(void)
 154 {
 155         unsigned long flags;
 156
 157         local_irq_save(flags);
 158         blast_icache32();
 159         local_irq_restore(flags);
 160 }
 161
 162 static inline void tx49_blast_icache32(void)
 163 {
 164         unsigned long start = INDEX_BASE;
 165         unsigned long end = start + current_cpu_data.icache.waysize;
 166         unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
 167         unsigned long ws_end = current_cpu_data.icache.ways <<
 168                                current_cpu_data.icache.waybit;
 169         unsigned long ws, addr;
 170
 171         CACHE32_UNROLL32_ALIGN2;
 172         /* I'm in even chunk.  blast odd chunks */
 173         for (ws = 0; ws < ws_end; ws += ws_inc)
 174                 for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
 175                         cache32_unroll32(addr|ws, Index_Invalidate_I);
 176         CACHE32_UNROLL32_ALIGN;
 177         /* I'm in odd chunk.  blast even chunks */
 178         for (ws = 0; ws < ws_end; ws += ws_inc)
 179                 for (addr = start; addr < end; addr += 0x400 * 2)
 180                         cache32_unroll32(addr|ws, Index_Invalidate_I);
 181 }
 182
 183 static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
 184 {
 185         unsigned long flags;
 186
 187         local_irq_save(flags);
 188         blast_icache32_page_indexed(page);
 189         local_irq_restore(flags);
 190 }
 191
 192 static inline void tx49_blast_icache32_page_indexed(unsigned long page)
 193 {
 194         unsigned long indexmask = current_cpu_data.icache.waysize - 1;
 195         unsigned long start = INDEX_BASE + (page & indexmask);
 196         unsigned long end = start + PAGE_SIZE;
 197         unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
 198         unsigned long ws_end = current_cpu_data.icache.ways <<
 199                                current_cpu_data.icache.waybit;
 200         unsigned long ws, addr;
 201
 202         CACHE32_UNROLL32_ALIGN2;
 203         /* I'm in even chunk.  blast odd chunks */
 204         for (ws = 0; ws < ws_end; ws += ws_inc)
 205                 for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
 206                         cache32_unroll32(addr|ws, Index_Invalidate_I);
 207         CACHE32_UNROLL32_ALIGN;
 208         /* I'm in odd chunk.  blast even chunks */
 209         for (ws = 0; ws < ws_end; ws += ws_inc)
 210                 for (addr = start; addr < end; addr += 0x400 * 2)
 211                         cache32_unroll32(addr|ws, Index_Invalidate_I);
 212 }
 213
 214 static void (* r4k_blast_icache_page)(unsigned long addr);
 215
 216 static void __cpuinit r4k_blast_icache_page_setup(void)
 217 {
 218         unsigned long ic_lsize = cpu_icache_line_size();
 219
 220         if (ic_lsize == 0)
 221                 r4k_blast_icache_page = (void *)cache_noop;
 222         else if (ic_lsize == 16)
 223                 r4k_blast_icache_page = blast_icache16_page;
 224         else if (ic_lsize == 32)
 225                 r4k_blast_icache_page = blast_icache32_page;
 226         else if (ic_lsize == 64)
 227                 r4k_blast_icache_page = blast_icache64_page;
 228 }
 229
 230
 231 static void (* r4k_blast_icache_page_indexed)(unsigned long addr);
 232
 233 static void __cpuinit r4k_blast_icache_page_indexed_setup(void)
 234 {
 235         unsigned long ic_lsize = cpu_icache_line_size();
 236
 237         if (ic_lsize == 0)
 238                 r4k_blast_icache_page_indexed = (void *)cache_noop;
 239         else if (ic_lsize == 16)
 240                 r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
 241         else if (ic_lsize == 32) {
 242                 if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
 243                         r4k_blast_icache_page_indexed =
 244                                 blast_icache32_r4600_v1_page_indexed;
 245                 else if (TX49XX_ICACHE_INDEX_INV_WAR)
 246                         r4k_blast_icache_page_indexed =
 247                                 tx49_blast_icache32_page_indexed;
 248                 else
 249                         r4k_blast_icache_page_indexed =
 250                                 blast_icache32_page_indexed;
 251         } else if (ic_lsize == 64)
 252                 r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
 253 }
 254
 255 static void (* r4k_blast_icache)(void);
 256
 257 static void __cpuinit r4k_blast_icache_setup(void)
 258 {
 259         unsigned long ic_lsize = cpu_icache_line_size();
 260
 261         if (ic_lsize == 0)
 262                 r4k_blast_icache = (void *)cache_noop;
 263         else if (ic_lsize == 16)
 264                 r4k_blast_icache = blast_icache16;
 265         else if (ic_lsize == 32) {
 266                 if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
 267                         r4k_blast_icache = blast_r4600_v1_icache32;
 268                 else if (TX49XX_ICACHE_INDEX_INV_WAR)
 269                         r4k_blast_icache = tx49_blast_icache32;
 270                 else
 271                         r4k_blast_icache = blast_icache32;
 272         } else if (ic_lsize == 64)
 273                 r4k_blast_icache = blast_icache64;
 274 }
 275
 276 static void (* r4k_blast_scache_page)(unsigned long addr);
 277
 278 static void __cpuinit r4k_blast_scache_page_setup(void)
 279 {
 280         unsigned long sc_lsize = cpu_scache_line_size();
 281
 282         if (scache_size == 0)
 283                 r4k_blast_scache_page = (void *)cache_noop;
 284         else if (sc_lsize == 16)
 285                 r4k_blast_scache_page = blast_scache16_page;
 286         else if (sc_lsize == 32)
 287                 r4k_blast_scache_page = blast_scache32_page;
 288         else if (sc_lsize == 64)
 289                 r4k_blast_scache_page = blast_scache64_page;
 290         else if (sc_lsize == 128)
 291                 r4k_blast_scache_page = blast_scache128_page;
 292 }
 293
 294 static void (* r4k_blast_scache_page_indexed)(unsigned long addr);
 295
 296 static void __cpuinit r4k_blast_scache_page_indexed_setup(void)
 297 {
 298         unsigned long sc_lsize = cpu_scache_line_size();
 299
 300         if (scache_size == 0)
 301                 r4k_blast_scache_page_indexed = (void *)cache_noop;
 302         else if (sc_lsize == 16)
 303                 r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
 304         else if (sc_lsize == 32)
 305                 r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
 306         else if (sc_lsize == 64)
 307                 r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
 308         else if (sc_lsize == 128)
 309                 r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
 310 }
 311
 312 static void (* r4k_blast_scache)(void);
 313
 314 static void __cpuinit r4k_blast_scache_setup(void)
 315 {
 316         unsigned long sc_lsize = cpu_scache_line_size();
 317
 318         if (scache_size == 0)
 319                 r4k_blast_scache = (void *)cache_noop;
 320         else if (sc_lsize == 16)
 321                 r4k_blast_scache = blast_scache16;
 322         else if (sc_lsize == 32)
 323                 r4k_blast_scache = blast_scache32;
 324         else if (sc_lsize == 64)
 325                 r4k_blast_scache = blast_scache64;
 326         else if (sc_lsize == 128)
 327                 r4k_blast_scache = blast_scache128;
 328 }
 329
 330 static inline void local_r4k___flush_cache_all(void * args)
 331 {
 332 #if defined(CONFIG_CPU_LOONGSON2)
 333         r4k_blast_scache();
 334         return;
 335 #endif
 336         r4k_blast_dcache();
 337         r4k_blast_icache();
 338
 339         switch (current_cpu_type()) {
 340         case CPU_R4000SC:
 341         case CPU_R4000MC:
 342         case CPU_R4400SC:
 343         case CPU_R4400MC:
 344         case CPU_R10000:
 345         case CPU_R12000:
 346         case CPU_R14000:
 347                 r4k_blast_scache();
 348         }
 349 }
 350
 351 static void r4k___flush_cache_all(void)
 352 {
 353         r4k_on_each_cpu(local_r4k___flush_cache_all, NULL, 1);
 354 }
 355
 356 static inline int has_valid_asid(const struct mm_struct *mm)
 357 {
 358 #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
 359         int i;
 360
 361         for_each_online_cpu(i)
 362                 if (cpu_context(i, mm))
 363                         return 1;
 364
 365         return 0;
 366 #else
 367         return cpu_context(smp_processor_id(), mm);
 368 #endif
 369 }
 370
 371 static void r4k__flush_cache_vmap(void)
 372 {
 373         r4k_blast_dcache();
 374 }
 375
 376 static void r4k__flush_cache_vunmap(void)
 377 {
 378         r4k_blast_dcache();
 379 }
 380
 381 static inline void local_r4k_flush_cache_range(void * args)
 382 {
 383         struct vm_area_struct *vma = args;
 384         int exec = vma->vm_flags & VM_EXEC;
 385
 386         if (!(has_valid_asid(vma->vm_mm)))
 387                 return;
 388
 389         r4k_blast_dcache();
 390         if (exec)
 391                 r4k_blast_icache();
 392 }
 393
 394 static void r4k_flush_cache_range(struct vm_area_struct *vma,
 395         unsigned long start, unsigned long end)
 396 {
 397         int exec = vma->vm_flags & VM_EXEC;
 398
 399         if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc))
 400                 r4k_on_each_cpu(local_r4k_flush_cache_range, vma, 1);
 401 }
 402
 403 static inline void local_r4k_flush_cache_mm(void * args)
 404 {
 405         struct mm_struct *mm = args;
 406
 407         if (!has_valid_asid(mm))
 408                 return;
 409
 410         /*
 411          * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
 412          * only flush the primary caches but R10000 and R12000 behave sane ...
 413          * R4000SC and R4400SC indexed S-cache ops also invalidate primary
 414          * caches, so we can bail out early.
 415          */
 416         if (current_cpu_type() == CPU_R4000SC ||
 417             current_cpu_type() == CPU_R4000MC ||
 418             current_cpu_type() == CPU_R4400SC ||
 419             current_cpu_type() == CPU_R4400MC) {
 420                 r4k_blast_scache();
 421                 return;
 422         }
 423
 424         r4k_blast_dcache();
 425 }
 426
 427 static void r4k_flush_cache_mm(struct mm_struct *mm)
 428 {
 429         if (!cpu_has_dc_aliases)
 430                 return;
 431
 432         r4k_on_each_cpu(local_r4k_flush_cache_mm, mm, 1);
 433 }
 434
 435 struct flush_cache_page_args {
 436         struct vm_area_struct *vma;
 437         unsigned long addr;
 438         unsigned long pfn;
 439 };
 440
 441 static inline void local_r4k_flush_cache_page(void *args)
 442 {
 443         struct flush_cache_page_args *fcp_args = args;
 444         struct vm_area_struct *vma = fcp_args->vma;
 445         unsigned long addr = fcp_args->addr;
 446         struct page *page = pfn_to_page(fcp_args->pfn);
 447         int exec = vma->vm_flags & VM_EXEC;
 448         struct mm_struct *mm = vma->vm_mm;
 449         int map_coherent = 0;
 450         pgd_t *pgdp;
 451         pud_t *pudp;
 452         pmd_t *pmdp;
 453         pte_t *ptep;
 454         void *vaddr;
 455
 456         /*
 457          * If ownes no valid ASID yet, cannot possibly have gotten
 458          * this page into the cache.
 459          */
 460         if (!has_valid_asid(mm))
 461                 return;
 462
 463         addr &= PAGE_MASK;
 464         pgdp = pgd_offset(mm, addr);
 465         pudp = pud_offset(pgdp, addr);
 466         pmdp = pmd_offset(pudp, addr);
 467         ptep = pte_offset(pmdp, addr);
 468
 469         /*
 470          * If the page isn't marked valid, the page cannot possibly be
 471          * in the cache.
 472          */
 473         if (!(pte_present(*ptep)))
 474                 return;
 475
 476         if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID))
 477                 vaddr = NULL;
 478         else {
 479                 /*
 480                  * Use kmap_coherent or kmap_atomic to do flushes for
 481                  * another ASID than the current one.
 482                  */
 483                 map_coherent = (cpu_has_dc_aliases &&
 484                                 page_mapped(page) && !Page_dcache_dirty(page));
 485                 if (map_coherent)
 486                         vaddr = kmap_coherent(page, addr);
 487                 else
 488                         vaddr = kmap_atomic(page, KM_USER0);
 489                 addr = (unsigned long)vaddr;
 490         }
 491
 492         if (cpu_has_dc_aliases || (exec && !cpu_has_ic_fills_f_dc)) {
 493                 r4k_blast_dcache_page(addr);
 494                 if (exec && !cpu_icache_snoops_remote_store)
 495                         r4k_blast_scache_page(addr);
 496         }
 497         if (exec) {
 498                 if (vaddr && cpu_has_vtag_icache && mm == current->active_mm) {
 499                         int cpu = smp_processor_id();
 500
 501                         if (cpu_context(cpu, mm) != 0)
 502                                 drop_mmu_context(mm, cpu);
 503                 } else
 504                         r4k_blast_icache_page(addr);
 505         }
 506
 507         if (vaddr) {
 508                 if (map_coherent)
 509                         kunmap_coherent();
 510                 else
 511                         kunmap_atomic(vaddr, KM_USER0);
 512         }
 513 }
 514
 515 static void r4k_flush_cache_page(struct vm_area_struct *vma,
 516         unsigned long addr, unsigned long pfn)
 517 {
 518         struct flush_cache_page_args args;
 519
 520         args.vma = vma;
 521         args.addr = addr;
 522         args.pfn = pfn;
 523
 524         r4k_on_each_cpu(local_r4k_flush_cache_page, &args, 1);
 525 }
 526
 527 static inline void local_r4k_flush_data_cache_page(void * addr)
 528 {
 529         r4k_blast_dcache_page((unsigned long) addr);
 530 }
 531
 532 static void r4k_flush_data_cache_page(unsigned long addr)
 533 {
 534         if (in_atomic())
 535                 local_r4k_flush_data_cache_page((void *)addr);
 536         else
 537                 r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr,
 538                                 1);
 539 }
 540
 541 struct flush_icache_range_args {
 542         unsigned long start;
 543         unsigned long end;
 544 };
 545
 546 static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
 547 {
 548         if (!cpu_has_ic_fills_f_dc) {
 549                 if (end - start >= dcache_size) {
 550                         r4k_blast_dcache();
 551                 } else {
 552                         R4600_HIT_CACHEOP_WAR_IMPL;
 553                         protected_blast_dcache_range(start, end);
 554                 }
 555         }
 556
 557         if (end - start > icache_size)
 558                 r4k_blast_icache();
 559         else
 560                 protected_blast_icache_range(start, end);
 561 }
 562
 563 static inline void local_r4k_flush_icache_range_ipi(void *args)
 564 {
 565         struct flush_icache_range_args *fir_args = args;
 566         unsigned long start = fir_args->start;
 567         unsigned long end = fir_args->end;
 568
 569         local_r4k_flush_icache_range(start, end);
 570 }
 571
 572 static void r4k_flush_icache_range(unsigned long start, unsigned long end)
 573 {
 574         struct flush_icache_range_args args;
 575
 576         args.start = start;
 577         args.end = end;
 578
 579         r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args, 1);
 580         instruction_hazard();
 581 }
 582
 583 #ifdef CONFIG_DMA_NONCOHERENT
 584
 585 static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
 586 {
 587         /* Catch bad driver code */
 588         BUG_ON(size == 0);
 589
 590         if (cpu_has_inclusive_pcaches) {
 591                 if (size >= scache_size)
 592                         r4k_blast_scache();
 593                 else
 594                         blast_scache_range(addr, addr + size);
 595                 return;
 596         }
 597
 598         /*
 599          * Either no secondary cache or the available caches don't have the
 600          * subset property so we have to flush the primary caches
 601          * explicitly
 602          */
 603         if (cpu_has_safe_index_cacheops && size >= dcache_size) {
 604                 r4k_blast_dcache();
 605         } else {
 606                 R4600_HIT_CACHEOP_WAR_IMPL;
 607                 blast_dcache_range(addr, addr + size);
 608         }
 609
 610         bc_wback_inv(addr, size);
 611 }
 612
 613 static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
 614 {
 615         /* Catch bad driver code */
 616         BUG_ON(size == 0);
 617
 618         if (cpu_has_inclusive_pcaches) {
 619                 if (size >= scache_size)
 620                         r4k_blast_scache();
 621                 else
 622                         blast_inv_scache_range(addr, addr + size);
 623                 return;
 624         }
 625
 626         if (cpu_has_safe_index_cacheops && size >= dcache_size) {
 627                 r4k_blast_dcache();
 628         } else {
 629                 R4600_HIT_CACHEOP_WAR_IMPL;
 630                 blast_inv_dcache_range(addr, addr + size);
 631         }
 632
 633         bc_inv(addr, size);
 634 }
 635 #endif /* CONFIG_DMA_NONCOHERENT */
 636
 637 /*
 638  * While we're protected against bad userland addresses we don't care
 639  * very much about what happens in that case.  Usually a segmentation
 640  * fault will dump the process later on anyway ...
 641  */
 642 static void local_r4k_flush_cache_sigtramp(void * arg)
 643 {
 644         unsigned long ic_lsize = cpu_icache_line_size();
 645         unsigned long dc_lsize = cpu_dcache_line_size();
 646         unsigned long sc_lsize = cpu_scache_line_size();
 647         unsigned long addr = (unsigned long) arg;
 648
 649         R4600_HIT_CACHEOP_WAR_IMPL;
 650         if (dc_lsize)
 651                 protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
 652         if (!cpu_icache_snoops_remote_store && scache_size)
 653                 protected_writeback_scache_line(addr & ~(sc_lsize - 1));
 654         if (ic_lsize)
 655                 protected_flush_icache_line(addr & ~(ic_lsize - 1));
 656         if (MIPS4K_ICACHE_REFILL_WAR) {
 657                 __asm__ __volatile__ (
 658                         ".set push\n\t"
 659                         ".set noat\n\t"
 660                         ".set mips3\n\t"
 661 #ifdef CONFIG_32BIT
 662                         "la     $at,1f\n\t"
 663 #endif
 664 #ifdef CONFIG_64BIT
 665                         "dla    $at,1f\n\t"
 666 #endif
 667                         "cache  %0,($at)\n\t"
 668                         "nop; nop; nop\n"
 669                         "1:\n\t"
 670                         ".set pop"
 671                         :
 672                         : "i" (Hit_Invalidate_I));
 673         }
 674         if (MIPS_CACHE_SYNC_WAR)
 675                 __asm__ __volatile__ ("sync");
 676 }
 677
 678 static void r4k_flush_cache_sigtramp(unsigned long addr)
 679 {
 680         r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr, 1);
 681 }
 682
 683 static void r4k_flush_icache_all(void)
 684 {
 685         if (cpu_has_vtag_icache)
 686                 r4k_blast_icache();
 687 }
 688
 689 static inline void rm7k_erratum31(void)
 690 {
 691         const unsigned long ic_lsize = 32;
 692         unsigned long addr;
 693
 694         /* RM7000 erratum #31. The icache is screwed at startup. */
 695         write_c0_taglo(0);
 696         write_c0_taghi(0);
 697
 698         for (addr = INDEX_BASE; addr <= INDEX_BASE + 4096; addr += ic_lsize) {
 699                 __asm__ __volatile__ (
 700                         ".set push\n\t"
 701                         ".set noreorder\n\t"
 702                         ".set mips3\n\t"
 703                         "cache\t%1, 0(%0)\n\t"
 704                         "cache\t%1, 0x1000(%0)\n\t"
 705                         "cache\t%1, 0x2000(%0)\n\t"
 706                         "cache\t%1, 0x3000(%0)\n\t"
 707                         "cache\t%2, 0(%0)\n\t"
 708                         "cache\t%2, 0x1000(%0)\n\t"
 709                         "cache\t%2, 0x2000(%0)\n\t"
 710                         "cache\t%2, 0x3000(%0)\n\t"
 711                         "cache\t%1, 0(%0)\n\t"
 712                         "cache\t%1, 0x1000(%0)\n\t"
 713                         "cache\t%1, 0x2000(%0)\n\t"
 714                         "cache\t%1, 0x3000(%0)\n\t"
 715                         ".set pop\n"
 716                         :
 717                         : "r" (addr), "i" (Index_Store_Tag_I), "i" (Fill));
 718         }
 719 }
 720
 721 static char *way_string[] __cpuinitdata = { NULL, "direct mapped", "2-way",
 722         "3-way", "4-way", "5-way", "6-way", "7-way", "8-way"
 723 };
 724
 725 static void __cpuinit probe_pcache(void)
 726 {
 727         struct cpuinfo_mips *c = &current_cpu_data;
 728         unsigned int config = read_c0_config();
 729         unsigned int prid = read_c0_prid();
 730         unsigned long config1;
 731         unsigned int lsize;
 732
 733         switch (c->cputype) {
 734         case CPU_R4600:                 /* QED style two way caches? */
 735         case CPU_R4700:
 736         case CPU_R5000:
 737         case CPU_NEVADA:
 738                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 739                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 740                 c->icache.ways = 2;
 741                 c->icache.waybit = __ffs(icache_size/2);
 742
 743                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 744                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 745                 c->dcache.ways = 2;
 746                 c->dcache.waybit= __ffs(dcache_size/2);
 747
 748                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 749                 break;
 750
 751         case CPU_R5432:
 752         case CPU_R5500:
 753                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 754                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 755                 c->icache.ways = 2;
 756                 c->icache.waybit= 0;
 757
 758                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 759                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 760                 c->dcache.ways = 2;
 761                 c->dcache.waybit = 0;
 762
 763                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 764                 break;
 765
 766         case CPU_TX49XX:
 767                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 768                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 769                 c->icache.ways = 4;
 770                 c->icache.waybit= 0;
 771
 772                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 773                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 774                 c->dcache.ways = 4;
 775                 c->dcache.waybit = 0;
 776
 777                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 778                 c->options |= MIPS_CPU_PREFETCH;
 779                 break;
 780
 781         case CPU_R4000PC:
 782         case CPU_R4000SC:
 783         case CPU_R4000MC:
 784         case CPU_R4400PC:
 785         case CPU_R4400SC:
 786         case CPU_R4400MC:
 787         case CPU_R4300:
 788                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 789                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 790                 c->icache.ways = 1;
 791                 c->icache.waybit = 0;   /* doesn't matter */
 792
 793                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 794                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 795                 c->dcache.ways = 1;
 796                 c->dcache.waybit = 0;   /* does not matter */
 797
 798                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 799                 break;
 800
 801         case CPU_R10000:
 802         case CPU_R12000:
 803         case CPU_R14000:
 804                 icache_size = 1 << (12 + ((config & R10K_CONF_IC) >> 29));
 805                 c->icache.linesz = 64;
 806                 c->icache.ways = 2;
 807                 c->icache.waybit = 0;
 808
 809                 dcache_size = 1 << (12 + ((config & R10K_CONF_DC) >> 26));
 810                 c->dcache.linesz = 32;
 811                 c->dcache.ways = 2;
 812                 c->dcache.waybit = 0;
 813
 814                 c->options |= MIPS_CPU_PREFETCH;
 815                 break;
 816
 817         case CPU_VR4133:
 818                 write_c0_config(config & ~VR41_CONF_P4K);
 819         case CPU_VR4131:
 820                 /* Workaround for cache instruction bug of VR4131 */
 821                 if (c->processor_id == 0x0c80U || c->processor_id == 0x0c81U ||
 822                     c->processor_id == 0x0c82U) {
 823                         config |= 0x00400000U;
 824                         if (c->processor_id == 0x0c80U)
 825                                 config |= VR41_CONF_BP;
 826                         write_c0_config(config);
 827                 } else
 828                         c->options |= MIPS_CPU_CACHE_CDEX_P;
 829
 830                 icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
 831                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 832                 c->icache.ways = 2;
 833                 c->icache.waybit = __ffs(icache_size/2);
 834
 835                 dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
 836                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 837                 c->dcache.ways = 2;
 838                 c->dcache.waybit = __ffs(dcache_size/2);
 839                 break;
 840
 841         case CPU_VR41XX:
 842         case CPU_VR4111:
 843         case CPU_VR4121:
 844         case CPU_VR4122:
 845         case CPU_VR4181:
 846         case CPU_VR4181A:
 847                 icache_size = 1 << (10 + ((config & CONF_IC) >> 9));
 848                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 849                 c->icache.ways = 1;
 850                 c->icache.waybit = 0;   /* doesn't matter */
 851
 852                 dcache_size = 1 << (10 + ((config & CONF_DC) >> 6));
 853                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 854                 c->dcache.ways = 1;
 855                 c->dcache.waybit = 0;   /* does not matter */
 856
 857                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 858                 break;
 859
 860         case CPU_RM7000:
 861                 rm7k_erratum31();
 862
 863         case CPU_RM9000:
 864                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 865                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 866                 c->icache.ways = 4;
 867                 c->icache.waybit = __ffs(icache_size / c->icache.ways);
 868
 869                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 870                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 871                 c->dcache.ways = 4;
 872                 c->dcache.waybit = __ffs(dcache_size / c->dcache.ways);
 873
 874 #if !defined(CONFIG_SMP) || !defined(RM9000_CDEX_SMP_WAR)
 875                 c->options |= MIPS_CPU_CACHE_CDEX_P;
 876 #endif
 877                 c->options |= MIPS_CPU_PREFETCH;
 878                 break;
 879
 880         case CPU_LOONGSON2:
 881                 icache_size = 1 << (12 + ((config & CONF_IC) >> 9));
 882                 c->icache.linesz = 16 << ((config & CONF_IB) >> 5);
 883                 if (prid & 0x3)
 884                         c->icache.ways = 4;
 885                 else
 886                         c->icache.ways = 2;
 887                 c->icache.waybit = 0;
 888
 889                 dcache_size = 1 << (12 + ((config & CONF_DC) >> 6));
 890                 c->dcache.linesz = 16 << ((config & CONF_DB) >> 4);
 891                 if (prid & 0x3)
 892                         c->dcache.ways = 4;
 893                 else
 894                         c->dcache.ways = 2;
 895                 c->dcache.waybit = 0;
 896                 break;
 897
 898         default:
 899                 if (!(config & MIPS_CONF_M))
 900                         panic("Don't know how to probe P-caches on this cpu.");
 901
 902                 /*
 903                  * So we seem to be a MIPS32 or MIPS64 CPU
 904                  * So let's probe the I-cache ...
 905                  */
 906                 config1 = read_c0_config1();
 907
 908                 if ((lsize = ((config1 >> 19) & 7)))
 909                         c->icache.linesz = 2 << lsize;
 910                 else
 911                         c->icache.linesz = lsize;
 912                 c->icache.sets = 64 << ((config1 >> 22) & 7);
 913                 c->icache.ways = 1 + ((config1 >> 16) & 7);
 914
 915                 icache_size = c->icache.sets *
 916                               c->icache.ways *
 917                               c->icache.linesz;
 918                 c->icache.waybit = __ffs(icache_size/c->icache.ways);
 919
 920                 if (config & 0x8)               /* VI bit */
 921                         c->icache.flags |= MIPS_CACHE_VTAG;
 922
 923                 /*
 924                  * Now probe the MIPS32 / MIPS64 data cache.
 925                  */
 926                 c->dcache.flags = 0;
 927
 928                 if ((lsize = ((config1 >> 10) & 7)))
 929                         c->dcache.linesz = 2 << lsize;
 930                 else
 931                         c->dcache.linesz= lsize;
 932                 c->dcache.sets = 64 << ((config1 >> 13) & 7);
 933                 c->dcache.ways = 1 + ((config1 >> 7) & 7);
 934
 935                 dcache_size = c->dcache.sets *
 936                               c->dcache.ways *
 937                               c->dcache.linesz;
 938                 c->dcache.waybit = __ffs(dcache_size/c->dcache.ways);
 939
 940                 c->options |= MIPS_CPU_PREFETCH;
 941                 break;
 942         }
 943
 944         /*
 945          * Processor configuration sanity check for the R4000SC erratum
 946          * #5.  With page sizes larger than 32kB there is no possibility
 947          * to get a VCE exception anymore so we don't care about this
 948          * misconfiguration.  The case is rather theoretical anyway;
 949          * presumably no vendor is shipping his hardware in the "bad"
 950          * configuration.
 951          */
 952         if ((prid & 0xff00) == PRID_IMP_R4000 && (prid & 0xff) < 0x40 &&
 953             !(config & CONF_SC) && c->icache.linesz != 16 &&
 954             PAGE_SIZE <= 0x8000)
 955                 panic("Improper R4000SC processor configuration detected");
 956
 957         /* compute a couple of other cache variables */
 958         c->icache.waysize = icache_size / c->icache.ways;
 959         c->dcache.waysize = dcache_size / c->dcache.ways;
 960
 961         c->icache.sets = c->icache.linesz ?
 962                 icache_size / (c->icache.linesz * c->icache.ways) : 0;
 963         c->dcache.sets = c->dcache.linesz ?
 964                 dcache_size / (c->dcache.linesz * c->dcache.ways) : 0;
 965
 966         /*
 967          * R10000 and R12000 P-caches are odd in a positive way.  They're 32kB
 968          * 2-way virtually indexed so normally would suffer from aliases.  So
 969          * normally they'd suffer from aliases but magic in the hardware deals
 970          * with that for us so we don't need to take care ourselves.
 971          */
 972         switch (c->cputype) {
 973         case CPU_20KC:
 974         case CPU_25KF:
 975         case CPU_SB1:
 976         case CPU_SB1A:
 977                 c->dcache.flags |= MIPS_CACHE_PINDEX;
 978                 break;
 979
 980         case CPU_R10000:
 981         case CPU_R12000:
 982         case CPU_R14000:
 983                 break;
 984
 985         case CPU_24K:
 986         case CPU_34K:
 987         case CPU_74K:
 988         case CPU_1004K:
 989                 if ((read_c0_config7() & (1 << 16))) {
 990                         /* effectively physically indexed dcache,
 991                            thus no virtual aliases. */
 992                         c->dcache.flags |= MIPS_CACHE_PINDEX;
 993                         break;
 994                 }
 995         default:
 996                 if (c->dcache.waysize > PAGE_SIZE)
 997                         c->dcache.flags |= MIPS_CACHE_ALIASES;
 998         }
 999
1000         switch (c->cputype) {
1001         case CPU_20KC:
1002                 /*
1003                  * Some older 20Kc chips doesn't have the 'VI' bit in
1004                  * the config register.
1005                  */
1006                 c->icache.flags |= MIPS_CACHE_VTAG;
1007                 break;
1008
1009         case CPU_AU1000:
1010         case CPU_AU1500:
1011         case CPU_AU1100:
1012         case CPU_AU1550:
1013         case CPU_AU1200:
1014         case CPU_AU1210:
1015         case CPU_AU1250:
1016                 c->icache.flags |= MIPS_CACHE_IC_F_DC;
1017                 break;
1018         }
1019
1020 #ifdef  CONFIG_CPU_LOONGSON2
1021         /*
1022          * LOONGSON2 has 4 way icache, but when using indexed cache op,
1023          * one op will act on all 4 ways
1024          */
1025         c->icache.ways = 1;
1026 #endif
1027
1028         printk("Primary instruction cache %ldkB, %s, %s, linesize %d bytes.\n",
1029                icache_size >> 10,
1030                cpu_has_vtag_icache ? "VIVT" : "VIPT",
1031                way_string[c->icache.ways], c->icache.linesz);
1032
1033         printk("Primary data cache %ldkB, %s, %s, %s, linesize %d bytes\n",
1034                dcache_size >> 10, way_string[c->dcache.ways],
1035                (c->dcache.flags & MIPS_CACHE_PINDEX) ? "PIPT" : "VIPT",
1036                (c->dcache.flags & MIPS_CACHE_ALIASES) ?
1037                         "cache aliases" : "no aliases",
1038                c->dcache.linesz);
1039 }
1040
1041 /*
1042  * If you even _breathe_ on this function, look at the gcc output and make sure
1043  * it does not pop things on and off the stack for the cache sizing loop that
1044  * executes in KSEG1 space or else you will crash and burn badly.  You have
1045  * been warned.
1046  */
1047 static int __cpuinit probe_scache(void)
1048 {
1049         unsigned long flags, addr, begin, end, pow2;
1050         unsigned int config = read_c0_config();
1051         struct cpuinfo_mips *c = &current_cpu_data;
1052         int tmp;
1053
1054         if (config & CONF_SC)
1055                 return 0;
1056
1057         begin = (unsigned long) &_stext;
1058         begin &= ~((4 * 1024 * 1024) - 1);
1059         end = begin + (4 * 1024 * 1024);
1060
1061         /*
1062          * This is such a bitch, you'd think they would make it easy to do
1063          * this.  Away you daemons of stupidity!
1064          */
1065         local_irq_save(flags);
1066
1067         /* Fill each size-multiple cache line with a valid tag. */
1068         pow2 = (64 * 1024);
1069         for (addr = begin; addr < end; addr = (begin + pow2)) {
1070                 unsigned long *p = (unsigned long *) addr;
1071                 __asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
1072                 pow2 <<= 1;
1073         }
1074
1075         /* Load first line with zero (therefore invalid) tag. */
1076         write_c0_taglo(0);
1077         write_c0_taghi(0);
1078         __asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
1079         cache_op(Index_Store_Tag_I, begin);
1080         cache_op(Index_Store_Tag_D, begin);
1081         cache_op(Index_Store_Tag_SD, begin);
1082
1083         /* Now search for the wrap around point. */
1084         pow2 = (128 * 1024);
1085         tmp = 0;
1086         for (addr = begin + (128 * 1024); addr < end; addr = begin + pow2) {
1087                 cache_op(Index_Load_Tag_SD, addr);
1088                 __asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
1089                 if (!read_c0_taglo())
1090                         break;
1091                 pow2 <<= 1;
1092         }
1093         local_irq_restore(flags);
1094         addr -= begin;
1095
1096         scache_size = addr;
1097         c->scache.linesz = 16 << ((config & R4K_CONF_SB) >> 22);
1098         c->scache.ways = 1;
1099         c->dcache.waybit = 0;           /* does not matter */
1100
1101         return 1;
1102 }
1103
1104 #if defined(CONFIG_CPU_LOONGSON2)
1105 static void __init loongson2_sc_init(void)
1106 {
1107         struct cpuinfo_mips *c = &current_cpu_data;
1108
1109         scache_size = 512*1024;
1110         c->scache.linesz = 32;
1111         c->scache.ways = 4;
1112         c->scache.waybit = 0;
1113         c->scache.waysize = scache_size / (c->scache.ways);
1114         c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1115         pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1116                scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1117
1118         c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1119 }
1120 #endif
1121
1122 extern int r5k_sc_init(void);
1123 extern int rm7k_sc_init(void);
1124 extern int mips_sc_init(void);
1125
1126 static void __cpuinit setup_scache(void)
1127 {
1128         struct cpuinfo_mips *c = &current_cpu_data;
1129         unsigned int config = read_c0_config();
1130         int sc_present = 0;
1131
1132         /*
1133          * Do the probing thing on R4000SC and R4400SC processors.  Other
1134          * processors don't have a S-cache that would be relevant to the
1135          * Linux memory management.
1136          */
1137         switch (c->cputype) {
1138         case CPU_R4000SC:
1139         case CPU_R4000MC:
1140         case CPU_R4400SC:
1141         case CPU_R4400MC:
1142                 sc_present = run_uncached(probe_scache);
1143                 if (sc_present)
1144                         c->options |= MIPS_CPU_CACHE_CDEX_S;
1145                 break;
1146
1147         case CPU_R10000:
1148         case CPU_R12000:
1149         case CPU_R14000:
1150                 scache_size = 0x80000 << ((config & R10K_CONF_SS) >> 16);
1151                 c->scache.linesz = 64 << ((config >> 13) & 1);
1152                 c->scache.ways = 2;
1153                 c->scache.waybit= 0;
1154                 sc_present = 1;
1155                 break;
1156
1157         case CPU_R5000:
1158         case CPU_NEVADA:
1159 #ifdef CONFIG_R5000_CPU_SCACHE
1160                 r5k_sc_init();
1161 #endif
1162                 return;
1163
1164         case CPU_RM7000:
1165         case CPU_RM9000:
1166 #ifdef CONFIG_RM7000_CPU_SCACHE
1167                 rm7k_sc_init();
1168 #endif
1169                 return;
1170
1171 #if defined(CONFIG_CPU_LOONGSON2)
1172         case CPU_LOONGSON2:
1173                 loongson2_sc_init();
1174                 return;
1175 #endif
1176
1177         default:
1178                 if (c->isa_level == MIPS_CPU_ISA_M32R1 ||
1179                     c->isa_level == MIPS_CPU_ISA_M32R2 ||
1180                     c->isa_level == MIPS_CPU_ISA_M64R1 ||
1181                     c->isa_level == MIPS_CPU_ISA_M64R2) {
1182 #ifdef CONFIG_MIPS_CPU_SCACHE
1183                         if (mips_sc_init ()) {
1184                                 scache_size = c->scache.ways * c->scache.sets * c->scache.linesz;
1185                                 printk("MIPS secondary cache %ldkB, %s, linesize %d bytes.\n",
1186                                        scache_size >> 10,
1187                                        way_string[c->scache.ways], c->scache.linesz);
1188                         }
1189 #else
1190                         if (!(c->scache.flags & MIPS_CACHE_NOT_PRESENT))
1191                                 panic("Dunno how to handle MIPS32 / MIPS64 second level cache");
1192 #endif
1193                         return;
1194                 }
1195                 sc_present = 0;
1196         }
1197
1198         if (!sc_present)
1199                 return;
1200
1201         /* compute a couple of other cache variables */
1202         c->scache.waysize = scache_size / c->scache.ways;
1203
1204         c->scache.sets = scache_size / (c->scache.linesz * c->scache.ways);
1205
1206         printk("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
1207                scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
1208
1209         c->options |= MIPS_CPU_INCLUSIVE_CACHES;
1210 }
1211
1212 void au1x00_fixup_config_od(void)
1213 {
1214         /*
1215          * c0_config.od (bit 19) was write only (and read as 0)
1216          * on the early revisions of Alchemy SOCs.  It disables the bus
1217          * transaction overlapping and needs to be set to fix various errata.
1218          */
1219         switch (read_c0_prid()) {
1220         case 0x00030100: /* Au1000 DA */
1221         case 0x00030201: /* Au1000 HA */
1222         case 0x00030202: /* Au1000 HB */
1223         case 0x01030200: /* Au1500 AB */
1224         /*
1225          * Au1100 errata actually keeps silence about this bit, so we set it
1226          * just in case for those revisions that require it to be set according
1227          * to arch/mips/au1000/common/cputable.c
1228          */
1229         case 0x02030200: /* Au1100 AB */
1230         case 0x02030201: /* Au1100 BA */
1231         case 0x02030202: /* Au1100 BC */
1232                 set_c0_config(1 << 19);
1233                 break;
1234         }
1235 }
1236
1237 /* CP0 hazard avoidance. */
1238 #define NXP_BARRIER()                                                   \
1239          __asm__ __volatile__(                                          \
1240         ".set noreorder\n\t"                                            \
1241         "nop; nop; nop; nop; nop; nop;\n\t"                             \
1242         ".set reorder\n\t")
1243
1244 static void nxp_pr4450_fixup_config(void)
1245 {
1246         unsigned long config0;
1247
1248         config0 = read_c0_config();
1249
1250         /* clear all three cache coherency fields */
1251         config0 &= ~(0x7 | (7 << 25) | (7 << 28));
1252         config0 |= (((_page_cachable_default >> _CACHE_SHIFT) <<  0) |
1253                     ((_page_cachable_default >> _CACHE_SHIFT) << 25) |
1254                     ((_page_cachable_default >> _CACHE_SHIFT) << 28));
1255         write_c0_config(config0);
1256         NXP_BARRIER();
1257 }
1258
1259 static int __cpuinitdata cca = -1;
1260
1261 static int __init cca_setup(char *str)
1262 {
1263         get_option(&str, &cca);
1264
1265         return 1;
1266 }
1267
1268 __setup("cca=", cca_setup);
1269
1270 static void __cpuinit coherency_setup(void)
1271 {
1272         if (cca < 0 || cca > 7)
1273                 cca = read_c0_config() & CONF_CM_CMASK;
1274         _page_cachable_default = cca << _CACHE_SHIFT;
1275
1276         pr_debug("Using cache attribute %d\n", cca);
1277         change_c0_config(CONF_CM_CMASK, cca);
1278
1279         /*
1280          * c0_status.cu=0 specifies that updates by the sc instruction use
1281          * the coherency mode specified by the TLB; 1 means cachable
1282          * coherent update on write will be used.  Not all processors have
1283          * this bit and; some wire it to zero, others like Toshiba had the
1284          * silly idea of putting something else there ...
1285          */
1286         switch (current_cpu_type()) {
1287         case CPU_R4000PC:
1288         case CPU_R4000SC:
1289         case CPU_R4000MC:
1290         case CPU_R4400PC:
1291         case CPU_R4400SC:
1292         case CPU_R4400MC:
1293                 clear_c0_config(CONF_CU);
1294                 break;
1295         /*
1296          * We need to catch the early Alchemy SOCs with
1297          * the write-only co_config.od bit and set it back to one...
1298          */
1299         case CPU_AU1000: /* rev. DA, HA, HB */
1300         case CPU_AU1100: /* rev. AB, BA, BC ?? */
1301         case CPU_AU1500: /* rev. AB */
1302                 au1x00_fixup_config_od();
1303                 break;
1304
1305         case PRID_IMP_PR4450:
1306                 nxp_pr4450_fixup_config();
1307                 break;
1308         }
1309 }
1310
1311 #if defined(CONFIG_DMA_NONCOHERENT)
1312
1313 static int __cpuinitdata coherentio;
1314
1315 static int __init setcoherentio(char *str)
1316 {
1317         coherentio = 1;
1318
1319         return 1;
1320 }
1321
1322 __setup("coherentio", setcoherentio);
1323 #endif
1324
1325 void __cpuinit r4k_cache_init(void)
1326 {
1327         extern void build_clear_page(void);
1328         extern void build_copy_page(void);
1329         extern char __weak except_vec2_generic;
1330         extern char __weak except_vec2_sb1;
1331         struct cpuinfo_mips *c = &current_cpu_data;
1332
1333         switch (c->cputype) {
1334         case CPU_SB1:
1335         case CPU_SB1A:
1336                 set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
1337                 break;
1338
1339         default:
1340                 set_uncached_handler(0x100, &except_vec2_generic, 0x80);
1341                 break;
1342         }
1343
1344         probe_pcache();
1345         setup_scache();
1346
1347         r4k_blast_dcache_page_setup();
1348         r4k_blast_dcache_page_indexed_setup();
1349         r4k_blast_dcache_setup();
1350         r4k_blast_icache_page_setup();
1351         r4k_blast_icache_page_indexed_setup();
1352         r4k_blast_icache_setup();
1353         r4k_blast_scache_page_setup();
1354         r4k_blast_scache_page_indexed_setup();
1355         r4k_blast_scache_setup();
1356
1357         /*
1358          * Some MIPS32 and MIPS64 processors have physically indexed caches.
1359          * This code supports virtually indexed processors and will be
1360          * unnecessarily inefficient on physically indexed processors.
1361          */
1362         if (c->dcache.linesz)
1363                 shm_align_mask = max_t( unsigned long,
1364                                         c->dcache.sets * c->dcache.linesz - 1,
1365                                         PAGE_SIZE - 1);
1366         else
1367                 shm_align_mask = PAGE_SIZE-1;
1368
1369         __flush_cache_vmap      = r4k__flush_cache_vmap;
1370         __flush_cache_vunmap    = r4k__flush_cache_vunmap;
1371
1372         flush_cache_all         = cache_noop;
1373         __flush_cache_all       = r4k___flush_cache_all;
1374         flush_cache_mm          = r4k_flush_cache_mm;
1375         flush_cache_page        = r4k_flush_cache_page;
1376         flush_cache_range       = r4k_flush_cache_range;
1377
1378         flush_cache_sigtramp    = r4k_flush_cache_sigtramp;
1379         flush_icache_all        = r4k_flush_icache_all;
1380         local_flush_data_cache_page     = local_r4k_flush_data_cache_page;
1381         flush_data_cache_page   = r4k_flush_data_cache_page;
1382         flush_icache_range      = r4k_flush_icache_range;
1383         local_flush_icache_range        = local_r4k_flush_icache_range;
1384
1385 #if defined(CONFIG_DMA_NONCOHERENT)
1386         if (coherentio) {
1387                 _dma_cache_wback_inv    = (void *)cache_noop;
1388                 _dma_cache_wback        = (void *)cache_noop;
1389                 _dma_cache_inv          = (void *)cache_noop;
1390         } else {
1391                 _dma_cache_wback_inv    = r4k_dma_cache_wback_inv;
1392                 _dma_cache_wback        = r4k_dma_cache_wback_inv;
1393                 _dma_cache_inv          = r4k_dma_cache_inv;
1394         }
1395 #endif
1396
1397         build_clear_page();
1398         build_copy_page();
1399 #if !defined(CONFIG_MIPS_CMP)
1400         local_r4k___flush_cache_all(NULL);
1401 #endif
1402         coherency_setup();
1403 }