arch/parisc/kernel/cache.c

   1 /* $Id: cache.c,v 1.4 2000/01/25 00:11:38 prumpf Exp $
   2  *
   3  * This file is subject to the terms and conditions of the GNU General Public
   4  * License.  See the file "COPYING" in the main directory of this archive
   5  * for more details.
   6  *
   7  * Copyright (C) 1999 Helge Deller (07-13-1999)
   8  * Copyright (C) 1999 SuSE GmbH Nuernberg
   9  * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
  10  *
  11  * Cache and TLB management
  12  *
  13  */
  14
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <linux/mm.h>
  18 #include <linux/module.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/pagemap.h>
  21
  22 #include <asm/pdc.h>
  23 #include <asm/cache.h>
  24 #include <asm/cacheflush.h>
  25 #include <asm/tlbflush.h>
  26 #include <asm/system.h>
  27 #include <asm/page.h>
  28 #include <asm/pgalloc.h>
  29 #include <asm/processor.h>
  30
  31 int split_tlb;
  32 int dcache_stride;
  33 int icache_stride;
  34 EXPORT_SYMBOL(dcache_stride);
  35
  36
  37 #if defined(CONFIG_SMP)
  38 /* On some machines (e.g. ones with the Merced bus), there can be
  39  * only a single PxTLB broadcast at a time; this must be guaranteed
  40  * by software.  We put a spinlock around all TLB flushes  to
  41  * ensure this.
  42  */
  43 DEFINE_SPINLOCK(pa_tlb_lock);
  44 EXPORT_SYMBOL(pa_tlb_lock);
  45 #endif
  46
  47 struct pdc_cache_info cache_info;
  48 #ifndef CONFIG_PA20
  49 static struct pdc_btlb_info btlb_info;
  50 #endif
  51
  52 #ifdef CONFIG_SMP
  53 void
  54 flush_data_cache(void)
  55 {
  56         on_each_cpu((void (*)(void *))flush_data_cache_local, NULL, 1, 1);
  57 }
  58 void
  59 flush_instruction_cache(void)
  60 {
  61         on_each_cpu((void (*)(void *))flush_instruction_cache_local, NULL, 1, 1);
  62 }
  63 #endif
  64
  65 void
  66 flush_cache_all_local(void)
  67 {
  68         flush_instruction_cache_local();
  69         flush_data_cache_local();
  70 }
  71 EXPORT_SYMBOL(flush_cache_all_local);
  72
  73 /* flushes EVERYTHING (tlb & cache) */
  74
  75 void
  76 flush_all_caches(void)
  77 {
  78         flush_cache_all();
  79         flush_tlb_all();
  80 }
  81 EXPORT_SYMBOL(flush_all_caches);
  82
  83 void
  84 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
  85 {
  86         struct page *page = pte_page(pte);
  87
  88         if (pfn_valid(page_to_pfn(page)) && page_mapping(page) &&
  89             test_bit(PG_dcache_dirty, &page->flags)) {
  90
  91                 flush_kernel_dcache_page(page_address(page));
  92                 clear_bit(PG_dcache_dirty, &page->flags);
  93         }
  94 }
  95
  96 void
  97 show_cache_info(struct seq_file *m)
  98 {
  99         seq_printf(m, "I-cache\t\t: %ld KB\n",
 100                 cache_info.ic_size/1024 );
 101         seq_printf(m, "D-cache\t\t: %ld KB (%s%s, %d-way associative)\n",
 102                 cache_info.dc_size/1024,
 103                 (cache_info.dc_conf.cc_wt ? "WT":"WB"),
 104                 (cache_info.dc_conf.cc_sh ? ", shared I/D":""),
 105                 (cache_info.dc_conf.cc_assoc)
 106         );
 107
 108         seq_printf(m, "ITLB entries\t: %ld\n" "DTLB entries\t: %ld%s\n",
 109                 cache_info.it_size,
 110                 cache_info.dt_size,
 111                 cache_info.dt_conf.tc_sh ? " - shared with ITLB":""
 112         );
 113
 114 #ifndef CONFIG_PA20
 115         /* BTLB - Block TLB */
 116         if (btlb_info.max_size==0) {
 117                 seq_printf(m, "BTLB\t\t: not supported\n" );
 118         } else {
 119                 seq_printf(m,
 120                 "BTLB fixed\t: max. %d pages, pagesize=%d (%dMB)\n"
 121                 "BTLB fix-entr.\t: %d instruction, %d data (%d combined)\n"
 122                 "BTLB var-entr.\t: %d instruction, %d data (%d combined)\n",
 123                 btlb_info.max_size, (int)4096,
 124                 btlb_info.max_size>>8,
 125                 btlb_info.fixed_range_info.num_i,
 126                 btlb_info.fixed_range_info.num_d,
 127                 btlb_info.fixed_range_info.num_comb,
 128                 btlb_info.variable_range_info.num_i,
 129                 btlb_info.variable_range_info.num_d,
 130                 btlb_info.variable_range_info.num_comb
 131                 );
 132         }
 133 #endif
 134 }
 135
 136 void __init
 137 parisc_cache_init(void)
 138 {
 139         if (pdc_cache_info(&cache_info) < 0)
 140                 panic("parisc_cache_init: pdc_cache_info failed");
 141
 142 #if 0
 143         printk("ic_size %lx dc_size %lx it_size %lx\n",
 144                 cache_info.ic_size,
 145                 cache_info.dc_size,
 146                 cache_info.it_size);
 147
 148         printk("DC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
 149                 cache_info.dc_base,
 150                 cache_info.dc_stride,
 151                 cache_info.dc_count,
 152                 cache_info.dc_loop);
 153
 154         printk("dc_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
 155                 *(unsigned long *) (&cache_info.dc_conf),
 156                 cache_info.dc_conf.cc_alias,
 157                 cache_info.dc_conf.cc_block,
 158                 cache_info.dc_conf.cc_line,
 159                 cache_info.dc_conf.cc_shift);
 160         printk("        wt %d sh %d cst %d assoc %d\n",
 161                 cache_info.dc_conf.cc_wt,
 162                 cache_info.dc_conf.cc_sh,
 163                 cache_info.dc_conf.cc_cst,
 164                 cache_info.dc_conf.cc_assoc);
 165
 166         printk("IC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
 167                 cache_info.ic_base,
 168                 cache_info.ic_stride,
 169                 cache_info.ic_count,
 170                 cache_info.ic_loop);
 171
 172         printk("ic_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
 173                 *(unsigned long *) (&cache_info.ic_conf),
 174                 cache_info.ic_conf.cc_alias,
 175                 cache_info.ic_conf.cc_block,
 176                 cache_info.ic_conf.cc_line,
 177                 cache_info.ic_conf.cc_shift);
 178         printk("        wt %d sh %d cst %d assoc %d\n",
 179                 cache_info.ic_conf.cc_wt,
 180                 cache_info.ic_conf.cc_sh,
 181                 cache_info.ic_conf.cc_cst,
 182                 cache_info.ic_conf.cc_assoc);
 183
 184         printk("D-TLB conf: sh %d page %d cst %d aid %d pad1 %d \n",
 185                 cache_info.dt_conf.tc_sh,
 186                 cache_info.dt_conf.tc_page,
 187                 cache_info.dt_conf.tc_cst,
 188                 cache_info.dt_conf.tc_aid,
 189                 cache_info.dt_conf.tc_pad1);
 190
 191         printk("I-TLB conf: sh %d page %d cst %d aid %d pad1 %d \n",
 192                 cache_info.it_conf.tc_sh,
 193                 cache_info.it_conf.tc_page,
 194                 cache_info.it_conf.tc_cst,
 195                 cache_info.it_conf.tc_aid,
 196                 cache_info.it_conf.tc_pad1);
 197 #endif
 198
 199         split_tlb = 0;
 200         if (cache_info.dt_conf.tc_sh == 0 || cache_info.dt_conf.tc_sh == 2) {
 201                 if (cache_info.dt_conf.tc_sh == 2)
 202                         printk(KERN_WARNING "Unexpected TLB configuration. "
 203                         "Will flush I/D separately (could be optimized).\n");
 204
 205                 split_tlb = 1;
 206         }
 207
 208         /* "New and Improved" version from Jim Hull
 209          *      (1 << (cc_block-1)) * (cc_line << (4 + cnf.cc_shift))
 210          */
 211 #define CAFL_STRIDE(cnf) (cnf.cc_line << (3 + cnf.cc_block + cnf.cc_shift))
 212         dcache_stride = CAFL_STRIDE(cache_info.dc_conf);
 213         icache_stride = CAFL_STRIDE(cache_info.ic_conf);
 214 #undef CAFL_STRIDE
 215
 216 #ifndef CONFIG_PA20
 217         if (pdc_btlb_info(&btlb_info) < 0) {
 218                 memset(&btlb_info, 0, sizeof btlb_info);
 219         }
 220 #endif
 221
 222         if ((boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) ==
 223                                                 PDC_MODEL_NVA_UNSUPPORTED) {
 224                 printk(KERN_WARNING "parisc_cache_init: Only equivalent aliasing supported!\n");
 225 #if 0
 226                 panic("SMP kernel required to avoid non-equivalent aliasing");
 227 #endif
 228         }
 229 }
 230
 231 void disable_sr_hashing(void)
 232 {
 233         int srhash_type;
 234
 235         switch (boot_cpu_data.cpu_type) {
 236         case pcx: /* We shouldn't get this far.  setup.c should prevent it. */
 237                 BUG();
 238                 return;
 239
 240         case pcxs:
 241         case pcxt:
 242         case pcxt_:
 243                 srhash_type = SRHASH_PCXST;
 244                 break;
 245
 246         case pcxl:
 247                 srhash_type = SRHASH_PCXL;
 248                 break;
 249
 250         case pcxl2: /* pcxl2 doesn't support space register hashing */
 251                 return;
 252
 253         default: /* Currently all PA2.0 machines use the same ins. sequence */
 254                 srhash_type = SRHASH_PA20;
 255                 break;
 256         }
 257
 258         disable_sr_hashing_asm(srhash_type);
 259 }
 260
 261 void flush_dcache_page(struct page *page)
 262 {
 263         struct address_space *mapping = page_mapping(page);
 264         struct vm_area_struct *mpnt;
 265         struct prio_tree_iter iter;
 266         unsigned long offset;
 267         unsigned long addr;
 268         pgoff_t pgoff;
 269         pte_t *pte;
 270         unsigned long pfn = page_to_pfn(page);
 271
 272
 273         if (mapping && !mapping_mapped(mapping)) {
 274                 set_bit(PG_dcache_dirty, &page->flags);
 275                 return;
 276         }
 277
 278         flush_kernel_dcache_page(page_address(page));
 279
 280         if (!mapping)
 281                 return;
 282
 283         pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
 284
 285         /* We have carefully arranged in arch_get_unmapped_area() that
 286          * *any* mappings of a file are always congruently mapped (whether
 287          * declared as MAP_PRIVATE or MAP_SHARED), so we only need
 288          * to flush one address here for them all to become coherent */
 289
 290         flush_dcache_mmap_lock(mapping);
 291         vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
 292                 offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
 293                 addr = mpnt->vm_start + offset;
 294
 295                 /* Flush instructions produce non access tlb misses.
 296                  * On PA, we nullify these instructions rather than
 297                  * taking a page fault if the pte doesn't exist.
 298                  * This is just for speed.  If the page translation
 299                  * isn't there, there's no point exciting the
 300                  * nadtlb handler into a nullification frenzy */
 301
 302
 303                 if(!(pte = translation_exists(mpnt, addr)))
 304                         continue;
 305
 306                 /* make sure we really have this page: the private
 307                  * mappings may cover this area but have COW'd this
 308                  * particular page */
 309                 if(pte_pfn(*pte) != pfn)
 310                         continue;
 311
 312                 __flush_cache_page(mpnt, addr);
 313
 314                 break;
 315         }
 316         flush_dcache_mmap_unlock(mapping);
 317 }
 318 EXPORT_SYMBOL(flush_dcache_page);
 319
 320 /* Defined in arch/parisc/kernel/pacache.S */
 321 EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
 322 EXPORT_SYMBOL(flush_kernel_dcache_page);
 323 EXPORT_SYMBOL(flush_data_cache_local);
 324 EXPORT_SYMBOL(flush_kernel_icache_range_asm);
 325
 326 void clear_user_page_asm(void *page, unsigned long vaddr)
 327 {
 328         /* This function is implemented in assembly in pacache.S */
 329         extern void __clear_user_page_asm(void *page, unsigned long vaddr);
 330
 331         purge_tlb_start();
 332         __clear_user_page_asm(page, vaddr);
 333         purge_tlb_end();
 334 }
 335
 336 #define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
 337 int parisc_cache_flush_threshold = FLUSH_THRESHOLD;
 338
 339 void parisc_setup_cache_timing(void)
 340 {
 341         unsigned long rangetime, alltime;
 342         extern char _text;      /* start of kernel code, defined by linker */
 343         extern char _end;       /* end of BSS, defined by linker */
 344         unsigned long size;
 345
 346         alltime = mfctl(16);
 347         flush_data_cache();
 348         alltime = mfctl(16) - alltime;
 349
 350         size = (unsigned long)(&_end - _text);
 351         rangetime = mfctl(16);
 352         flush_kernel_dcache_range((unsigned long)&_text, size);
 353         rangetime = mfctl(16) - rangetime;
 354
 355         printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
 356                 alltime, size, rangetime);
 357
 358         /* Racy, but if we see an intermediate value, it's ok too... */
 359         parisc_cache_flush_threshold = size * alltime / rangetime;
 360
 361         parisc_cache_flush_threshold = (parisc_cache_flush_threshold + L1_CACHE_BYTES - 1) &~ (L1_CACHE_BYTES - 1);
 362         if (!parisc_cache_flush_threshold)
 363                 parisc_cache_flush_threshold = FLUSH_THRESHOLD;
 364
 365         printk("Setting cache flush threshold to %x (%d CPUs online)\n", parisc_cache_flush_threshold, num_online_cpus());
 366 }