arch/parisc/kernel/cache.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) 1999-2006 Helge Deller <deller@gmx.de> (07-13-1999)
   7  * Copyright (C) 1999 SuSE GmbH Nuernberg
   8  * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
   9  *
  10  * Cache and TLB management
  11  *
  12  */
  13
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/mm.h>
  17 #include <linux/module.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/pagemap.h>
  20 #include <linux/sched.h>
  21 #include <asm/pdc.h>
  22 #include <asm/cache.h>
  23 #include <asm/cacheflush.h>
  24 #include <asm/tlbflush.h>
  25 #include <asm/page.h>
  26 #include <asm/pgalloc.h>
  27 #include <asm/processor.h>
  28 #include <asm/sections.h>
  29 #include <asm/shmparam.h>
  30
  31 int split_tlb __read_mostly;
  32 int dcache_stride __read_mostly;
  33 int icache_stride __read_mostly;
  34 EXPORT_SYMBOL(dcache_stride);
  35
  36 void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
  37 EXPORT_SYMBOL(flush_dcache_page_asm);
  38 void flush_icache_page_asm(unsigned long phys_addr, unsigned long vaddr);
  39
  40
  41 /* On some machines (e.g. ones with the Merced bus), there can be
  42  * only a single PxTLB broadcast at a time; this must be guaranteed
  43  * by software.  We put a spinlock around all TLB flushes  to
  44  * ensure this.
  45  */
  46 DEFINE_SPINLOCK(pa_tlb_lock);
  47
  48 struct pdc_cache_info cache_info __read_mostly;
  49 #ifndef CONFIG_PA20
  50 static struct pdc_btlb_info btlb_info __read_mostly;
  51 #endif
  52
  53 #ifdef CONFIG_SMP
  54 void
  55 flush_data_cache(void)
  56 {
  57         on_each_cpu(flush_data_cache_local, NULL, 1);
  58 }
  59 void
  60 flush_instruction_cache(void)
  61 {
  62         on_each_cpu(flush_instruction_cache_local, NULL, 1);
  63 }
  64 #endif
  65
  66 void
  67 flush_cache_all_local(void)
  68 {
  69         flush_instruction_cache_local(NULL);
  70         flush_data_cache_local(NULL);
  71 }
  72 EXPORT_SYMBOL(flush_cache_all_local);
  73
  74 void
  75 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
  76 {
  77         struct page *page = pte_page(*ptep);
  78
  79         if (pfn_valid(page_to_pfn(page)) && page_mapping(page) &&
  80             test_bit(PG_dcache_dirty, &page->flags)) {
  81
  82                 flush_kernel_dcache_page(page);
  83                 clear_bit(PG_dcache_dirty, &page->flags);
  84         } else if (parisc_requires_coherency())
  85                 flush_kernel_dcache_page(page);
  86 }
  87
  88 void
  89 show_cache_info(struct seq_file *m)
  90 {
  91         char buf[32];
  92
  93         seq_printf(m, "I-cache\t\t: %ld KB\n",
  94                 cache_info.ic_size/1024 );
  95         if (cache_info.dc_loop != 1)
  96                 snprintf(buf, 32, "%lu-way associative", cache_info.dc_loop);
  97         seq_printf(m, "D-cache\t\t: %ld KB (%s%s, %s)\n",
  98                 cache_info.dc_size/1024,
  99                 (cache_info.dc_conf.cc_wt ? "WT":"WB"),
 100                 (cache_info.dc_conf.cc_sh ? ", shared I/D":""),
 101                 ((cache_info.dc_loop == 1) ? "direct mapped" : buf));
 102         seq_printf(m, "ITLB entries\t: %ld\n" "DTLB entries\t: %ld%s\n",
 103                 cache_info.it_size,
 104                 cache_info.dt_size,
 105                 cache_info.dt_conf.tc_sh ? " - shared with ITLB":""
 106         );
 107
 108 #ifndef CONFIG_PA20
 109         /* BTLB - Block TLB */
 110         if (btlb_info.max_size==0) {
 111                 seq_printf(m, "BTLB\t\t: not supported\n" );
 112         } else {
 113                 seq_printf(m,
 114                 "BTLB fixed\t: max. %d pages, pagesize=%d (%dMB)\n"
 115                 "BTLB fix-entr.\t: %d instruction, %d data (%d combined)\n"
 116                 "BTLB var-entr.\t: %d instruction, %d data (%d combined)\n",
 117                 btlb_info.max_size, (int)4096,
 118                 btlb_info.max_size>>8,
 119                 btlb_info.fixed_range_info.num_i,
 120                 btlb_info.fixed_range_info.num_d,
 121                 btlb_info.fixed_range_info.num_comb,
 122                 btlb_info.variable_range_info.num_i,
 123                 btlb_info.variable_range_info.num_d,
 124                 btlb_info.variable_range_info.num_comb
 125                 );
 126         }
 127 #endif
 128 }
 129
 130 void __init
 131 parisc_cache_init(void)
 132 {
 133         if (pdc_cache_info(&cache_info) < 0)
 134                 panic("parisc_cache_init: pdc_cache_info failed");
 135
 136 #if 0
 137         printk("ic_size %lx dc_size %lx it_size %lx\n",
 138                 cache_info.ic_size,
 139                 cache_info.dc_size,
 140                 cache_info.it_size);
 141
 142         printk("DC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
 143                 cache_info.dc_base,
 144                 cache_info.dc_stride,
 145                 cache_info.dc_count,
 146                 cache_info.dc_loop);
 147
 148         printk("dc_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
 149                 *(unsigned long *) (&cache_info.dc_conf),
 150                 cache_info.dc_conf.cc_alias,
 151                 cache_info.dc_conf.cc_block,
 152                 cache_info.dc_conf.cc_line,
 153                 cache_info.dc_conf.cc_shift);
 154         printk("        wt %d sh %d cst %d hv %d\n",
 155                 cache_info.dc_conf.cc_wt,
 156                 cache_info.dc_conf.cc_sh,
 157                 cache_info.dc_conf.cc_cst,
 158                 cache_info.dc_conf.cc_hv);
 159
 160         printk("IC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
 161                 cache_info.ic_base,
 162                 cache_info.ic_stride,
 163                 cache_info.ic_count,
 164                 cache_info.ic_loop);
 165
 166         printk("ic_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
 167                 *(unsigned long *) (&cache_info.ic_conf),
 168                 cache_info.ic_conf.cc_alias,
 169                 cache_info.ic_conf.cc_block,
 170                 cache_info.ic_conf.cc_line,
 171                 cache_info.ic_conf.cc_shift);
 172         printk("        wt %d sh %d cst %d hv %d\n",
 173                 cache_info.ic_conf.cc_wt,
 174                 cache_info.ic_conf.cc_sh,
 175                 cache_info.ic_conf.cc_cst,
 176                 cache_info.ic_conf.cc_hv);
 177
 178         printk("D-TLB conf: sh %d page %d cst %d aid %d pad1 %d\n",
 179                 cache_info.dt_conf.tc_sh,
 180                 cache_info.dt_conf.tc_page,
 181                 cache_info.dt_conf.tc_cst,
 182                 cache_info.dt_conf.tc_aid,
 183                 cache_info.dt_conf.tc_pad1);
 184
 185         printk("I-TLB conf: sh %d page %d cst %d aid %d pad1 %d\n",
 186                 cache_info.it_conf.tc_sh,
 187                 cache_info.it_conf.tc_page,
 188                 cache_info.it_conf.tc_cst,
 189                 cache_info.it_conf.tc_aid,
 190                 cache_info.it_conf.tc_pad1);
 191 #endif
 192
 193         split_tlb = 0;
 194         if (cache_info.dt_conf.tc_sh == 0 || cache_info.dt_conf.tc_sh == 2) {
 195                 if (cache_info.dt_conf.tc_sh == 2)
 196                         printk(KERN_WARNING "Unexpected TLB configuration. "
 197                         "Will flush I/D separately (could be optimized).\n");
 198
 199                 split_tlb = 1;
 200         }
 201
 202         /* "New and Improved" version from Jim Hull
 203          *      (1 << (cc_block-1)) * (cc_line << (4 + cnf.cc_shift))
 204          * The following CAFL_STRIDE is an optimized version, see
 205          * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023625.html
 206          * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023671.html
 207          */
 208 #define CAFL_STRIDE(cnf) (cnf.cc_line << (3 + cnf.cc_block + cnf.cc_shift))
 209         dcache_stride = CAFL_STRIDE(cache_info.dc_conf);
 210         icache_stride = CAFL_STRIDE(cache_info.ic_conf);
 211 #undef CAFL_STRIDE
 212
 213 #ifndef CONFIG_PA20
 214         if (pdc_btlb_info(&btlb_info) < 0) {
 215                 memset(&btlb_info, 0, sizeof btlb_info);
 216         }
 217 #endif
 218
 219         if ((boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) ==
 220                                                 PDC_MODEL_NVA_UNSUPPORTED) {
 221                 printk(KERN_WARNING "parisc_cache_init: Only equivalent aliasing supported!\n");
 222 #if 0
 223                 panic("SMP kernel required to avoid non-equivalent aliasing");
 224 #endif
 225         }
 226 }
 227
 228 void disable_sr_hashing(void)
 229 {
 230         int srhash_type, retval;
 231         unsigned long space_bits;
 232
 233         switch (boot_cpu_data.cpu_type) {
 234         case pcx: /* We shouldn't get this far.  setup.c should prevent it. */
 235                 BUG();
 236                 return;
 237
 238         case pcxs:
 239         case pcxt:
 240         case pcxt_:
 241                 srhash_type = SRHASH_PCXST;
 242                 break;
 243
 244         case pcxl:
 245                 srhash_type = SRHASH_PCXL;
 246                 break;
 247
 248         case pcxl2: /* pcxl2 doesn't support space register hashing */
 249                 return;
 250
 251         default: /* Currently all PA2.0 machines use the same ins. sequence */
 252                 srhash_type = SRHASH_PA20;
 253                 break;
 254         }
 255
 256         disable_sr_hashing_asm(srhash_type);
 257
 258         retval = pdc_spaceid_bits(&space_bits);
 259         /* If this procedure isn't implemented, don't panic. */
 260         if (retval < 0 && retval != PDC_BAD_OPTION)
 261                 panic("pdc_spaceid_bits call failed.\n");
 262         if (space_bits != 0)
 263                 panic("SpaceID hashing is still on!\n");
 264 }
 265
 266 static inline void
 267 __flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
 268                    unsigned long physaddr)
 269 {
 270         flush_dcache_page_asm(physaddr, vmaddr);
 271         if (vma->vm_flags & VM_EXEC)
 272                 flush_icache_page_asm(physaddr, vmaddr);
 273 }
 274
 275 void flush_dcache_page(struct page *page)
 276 {
 277         struct address_space *mapping = page_mapping(page);
 278         struct vm_area_struct *mpnt;
 279         unsigned long offset;
 280         unsigned long addr, old_addr = 0;
 281         pgoff_t pgoff;
 282
 283         if (mapping && !mapping_mapped(mapping)) {
 284                 set_bit(PG_dcache_dirty, &page->flags);
 285                 return;
 286         }
 287
 288         flush_kernel_dcache_page(page);
 289
 290         if (!mapping)
 291                 return;
 292
 293         pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
 294
 295         /* We have carefully arranged in arch_get_unmapped_area() that
 296          * *any* mappings of a file are always congruently mapped (whether
 297          * declared as MAP_PRIVATE or MAP_SHARED), so we only need
 298          * to flush one address here for them all to become coherent */
 299
 300         flush_dcache_mmap_lock(mapping);
 301         vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
 302                 offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
 303                 addr = mpnt->vm_start + offset;
 304
 305                 /* The TLB is the engine of coherence on parisc: The
 306                  * CPU is entitled to speculate any page with a TLB
 307                  * mapping, so here we kill the mapping then flush the
 308                  * page along a special flush only alias mapping.
 309                  * This guarantees that the page is no-longer in the
 310                  * cache for any process and nor may it be
 311                  * speculatively read in (until the user or kernel
 312                  * specifically accesses it, of course) */
 313
 314                 flush_tlb_page(mpnt, addr);
 315                 if (old_addr == 0 || (old_addr & (SHMLBA - 1)) != (addr & (SHMLBA - 1))) {
 316                         __flush_cache_page(mpnt, addr, page_to_phys(page));
 317                         if (old_addr)
 318                                 printk(KERN_ERR "INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %s\n", old_addr, addr, mpnt->vm_file ? (char *)mpnt->vm_file->f_path.dentry->d_name.name : "(null)");
 319                         old_addr = addr;
 320                 }
 321         }
 322         flush_dcache_mmap_unlock(mapping);
 323 }
 324 EXPORT_SYMBOL(flush_dcache_page);
 325
 326 /* Defined in arch/parisc/kernel/pacache.S */
 327 EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
 328 EXPORT_SYMBOL(flush_kernel_dcache_page_asm);
 329 EXPORT_SYMBOL(flush_data_cache_local);
 330 EXPORT_SYMBOL(flush_kernel_icache_range_asm);
 331
 332 void clear_user_page_asm(void *page, unsigned long vaddr)
 333 {
 334         unsigned long flags;
 335         /* This function is implemented in assembly in pacache.S */
 336         extern void __clear_user_page_asm(void *page, unsigned long vaddr);
 337
 338         purge_tlb_start(flags);
 339         __clear_user_page_asm(page, vaddr);
 340         purge_tlb_end(flags);
 341 }
 342
 343 #define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
 344 int parisc_cache_flush_threshold __read_mostly = FLUSH_THRESHOLD;
 345
 346 void __init parisc_setup_cache_timing(void)
 347 {
 348         unsigned long rangetime, alltime;
 349         unsigned long size;
 350
 351         alltime = mfctl(16);
 352         flush_data_cache();
 353         alltime = mfctl(16) - alltime;
 354
 355         size = (unsigned long)(_end - _text);
 356         rangetime = mfctl(16);
 357         flush_kernel_dcache_range((unsigned long)_text, size);
 358         rangetime = mfctl(16) - rangetime;
 359
 360         printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
 361                 alltime, size, rangetime);
 362
 363         /* Racy, but if we see an intermediate value, it's ok too... */
 364         parisc_cache_flush_threshold = size * alltime / rangetime;
 365
 366         parisc_cache_flush_threshold = (parisc_cache_flush_threshold + L1_CACHE_BYTES - 1) &~ (L1_CACHE_BYTES - 1);
 367         if (!parisc_cache_flush_threshold)
 368                 parisc_cache_flush_threshold = FLUSH_THRESHOLD;
 369
 370         if (parisc_cache_flush_threshold > cache_info.dc_size)
 371                 parisc_cache_flush_threshold = cache_info.dc_size;
 372
 373         printk(KERN_INFO "Setting cache flush threshold to %x (%d CPUs online)\n", parisc_cache_flush_threshold, num_online_cpus());
 374 }
 375
 376 extern void purge_kernel_dcache_page(unsigned long);
 377 extern void clear_user_page_asm(void *page, unsigned long vaddr);
 378
 379 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
 380 {
 381         unsigned long flags;
 382
 383         purge_kernel_dcache_page((unsigned long)page);
 384         purge_tlb_start(flags);
 385         pdtlb_kernel(page);
 386         purge_tlb_end(flags);
 387         clear_user_page_asm(page, vaddr);
 388 }
 389 EXPORT_SYMBOL(clear_user_page);
 390
 391 void flush_kernel_dcache_page_addr(void *addr)
 392 {
 393         unsigned long flags;
 394
 395         flush_kernel_dcache_page_asm(addr);
 396         purge_tlb_start(flags);
 397         pdtlb_kernel(addr);
 398         purge_tlb_end(flags);
 399 }
 400 EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
 401
 402 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
 403                     struct page *pg)
 404 {
 405         /* no coherency needed (all in kmap/kunmap) */
 406         copy_user_page_asm(vto, vfrom);
 407         if (!parisc_requires_coherency())
 408                 flush_kernel_dcache_page_asm(vto);
 409 }
 410 EXPORT_SYMBOL(copy_user_page);
 411
 412 #ifdef CONFIG_PA8X00
 413
 414 void kunmap_parisc(void *addr)
 415 {
 416         if (parisc_requires_coherency())
 417                 flush_kernel_dcache_page_addr(addr);
 418 }
 419 EXPORT_SYMBOL(kunmap_parisc);
 420 #endif
 421
 422 void __flush_tlb_range(unsigned long sid, unsigned long start,
 423                        unsigned long end)
 424 {
 425         unsigned long npages;
 426
 427         npages = ((end - (start & PAGE_MASK)) + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
 428         if (npages >= 512)  /* 2MB of space: arbitrary, should be tuned */
 429                 flush_tlb_all();
 430         else {
 431                 unsigned long flags;
 432
 433                 mtsp(sid, 1);
 434                 purge_tlb_start(flags);
 435                 if (split_tlb) {
 436                         while (npages--) {
 437                                 pdtlb(start);
 438                                 pitlb(start);
 439                                 start += PAGE_SIZE;
 440                         }
 441                 } else {
 442                         while (npages--) {
 443                                 pdtlb(start);
 444                                 start += PAGE_SIZE;
 445                         }
 446                 }
 447                 purge_tlb_end(flags);
 448         }
 449 }
 450
 451 static void cacheflush_h_tmp_function(void *dummy)
 452 {
 453         flush_cache_all_local();
 454 }
 455
 456 void flush_cache_all(void)
 457 {
 458         on_each_cpu(cacheflush_h_tmp_function, NULL, 1);
 459 }
 460
 461 void flush_cache_mm(struct mm_struct *mm)
 462 {
 463 #ifdef CONFIG_SMP
 464         flush_cache_all();
 465 #else
 466         flush_cache_all_local();
 467 #endif
 468 }
 469
 470 void
 471 flush_user_dcache_range(unsigned long start, unsigned long end)
 472 {
 473         if ((end - start) < parisc_cache_flush_threshold)
 474                 flush_user_dcache_range_asm(start,end);
 475         else
 476                 flush_data_cache();
 477 }
 478
 479 void
 480 flush_user_icache_range(unsigned long start, unsigned long end)
 481 {
 482         if ((end - start) < parisc_cache_flush_threshold)
 483                 flush_user_icache_range_asm(start,end);
 484         else
 485                 flush_instruction_cache();
 486 }
 487
 488
 489 void flush_cache_range(struct vm_area_struct *vma,
 490                 unsigned long start, unsigned long end)
 491 {
 492         int sr3;
 493
 494         BUG_ON(!vma->vm_mm->context);
 495
 496         sr3 = mfsp(3);
 497         if (vma->vm_mm->context == sr3) {
 498                 flush_user_dcache_range(start,end);
 499                 flush_user_icache_range(start,end);
 500         } else {
 501                 flush_cache_all();
 502         }
 503 }
 504
 505 void
 506 flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
 507 {
 508         BUG_ON(!vma->vm_mm->context);
 509
 510         flush_tlb_page(vma, vmaddr);
 511         __flush_cache_page(vma, vmaddr, page_to_phys(pfn_to_page(pfn)));
 512
 513 }