arch/sparc/mm/init_32.c

   1 /*
   2  *  linux/arch/sparc/mm/init.c
   3  *
   4  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
   6  *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7  *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/signal.h>
  12 #include <linux/sched.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/string.h>
  16 #include <linux/types.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/mman.h>
  19 #include <linux/mm.h>
  20 #include <linux/swap.h>
  21 #include <linux/initrd.h>
  22 #include <linux/init.h>
  23 #include <linux/highmem.h>
  24 #include <linux/bootmem.h>
  25 #include <linux/pagemap.h>
  26 #include <linux/poison.h>
  27
  28 #include <asm/system.h>
  29 #include <asm/vac-ops.h>
  30 #include <asm/page.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/vaddrs.h>
  33 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  34 #include <asm/tlb.h>
  35 #include <asm/prom.h>
  36
  37 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  38
  39 unsigned long *sparc_valid_addr_bitmap;
  40
  41 unsigned long phys_base;
  42 unsigned long pfn_base;
  43
  44 unsigned long page_kernel;
  45
  46 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  47 unsigned long sparc_unmapped_base;
  48
  49 struct pgtable_cache_struct pgt_quicklists;
  50
  51 /* References to section boundaries */
  52 extern char __init_begin, __init_end, _start, _end, etext , edata;
  53
  54 /* Initial ramdisk setup */
  55 extern unsigned int sparc_ramdisk_image;
  56 extern unsigned int sparc_ramdisk_size;
  57
  58 unsigned long highstart_pfn, highend_pfn;
  59
  60 pte_t *kmap_pte;
  61 pgprot_t kmap_prot;
  62
  63 #define kmap_get_fixmap_pte(vaddr) \
  64         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
  65
  66 void __init kmap_init(void)
  67 {
  68         /* cache the first kmap pte */
  69         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
  70         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
  71 }
  72
  73 void show_mem(void)
  74 {
  75         printk("Mem-info:\n");
  76         show_free_areas();
  77         printk("Free swap:       %6ldkB\n",
  78                nr_swap_pages << (PAGE_SHIFT-10));
  79         printk("%ld pages of RAM\n", totalram_pages);
  80         printk("%ld free pages\n", nr_free_pages());
  81 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
  82         printk("%ld pages in page table cache\n",pgtable_cache_size);
  83 #ifndef CONFIG_SMP
  84         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
  85                 printk("%ld entries in page dir cache\n",pgd_cache_size);
  86 #endif
  87 #endif
  88 }
  89
  90 void __init sparc_context_init(int numctx)
  91 {
  92         int ctx;
  93
  94         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
  95
  96         for(ctx = 0; ctx < numctx; ctx++) {
  97                 struct ctx_list *clist;
  98
  99                 clist = (ctx_list_pool + ctx);
 100                 clist->ctx_number = ctx;
 101                 clist->ctx_mm = NULL;
 102         }
 103         ctx_free.next = ctx_free.prev = &ctx_free;
 104         ctx_used.next = ctx_used.prev = &ctx_used;
 105         for(ctx = 0; ctx < numctx; ctx++)
 106                 add_to_free_ctxlist(ctx_list_pool + ctx);
 107 }
 108
 109 extern unsigned long cmdline_memory_size;
 110 unsigned long last_valid_pfn;
 111
 112 unsigned long calc_highpages(void)
 113 {
 114         int i;
 115         int nr = 0;
 116
 117         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 118                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 119                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 120
 121                 if (end_pfn <= max_low_pfn)
 122                         continue;
 123
 124                 if (start_pfn < max_low_pfn)
 125                         start_pfn = max_low_pfn;
 126
 127                 nr += end_pfn - start_pfn;
 128         }
 129
 130         return nr;
 131 }
 132
 133 static unsigned long calc_max_low_pfn(void)
 134 {
 135         int i;
 136         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 137         unsigned long curr_pfn, last_pfn;
 138
 139         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
 140         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
 141                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 142
 143                 if (curr_pfn >= tmp) {
 144                         if (last_pfn < tmp)
 145                                 tmp = last_pfn;
 146                         break;
 147                 }
 148
 149                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 150         }
 151
 152         return tmp;
 153 }
 154
 155 unsigned long __init bootmem_init(unsigned long *pages_avail)
 156 {
 157         unsigned long bootmap_size, start_pfn;
 158         unsigned long end_of_phys_memory = 0UL;
 159         unsigned long bootmap_pfn, bytes_avail, size;
 160         int i;
 161
 162         bytes_avail = 0UL;
 163         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 164                 end_of_phys_memory = sp_banks[i].base_addr +
 165                         sp_banks[i].num_bytes;
 166                 bytes_avail += sp_banks[i].num_bytes;
 167                 if (cmdline_memory_size) {
 168                         if (bytes_avail > cmdline_memory_size) {
 169                                 unsigned long slack = bytes_avail - cmdline_memory_size;
 170
 171                                 bytes_avail -= slack;
 172                                 end_of_phys_memory -= slack;
 173
 174                                 sp_banks[i].num_bytes -= slack;
 175                                 if (sp_banks[i].num_bytes == 0) {
 176                                         sp_banks[i].base_addr = 0xdeadbeef;
 177                                 } else {
 178                                         sp_banks[i+1].num_bytes = 0;
 179                                         sp_banks[i+1].base_addr = 0xdeadbeef;
 180                                 }
 181                                 break;
 182                         }
 183                 }
 184         }
 185
 186         /* Start with page aligned address of last symbol in kernel
 187          * image.
 188          */
 189         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 190
 191         /* Now shift down to get the real physical page frame number. */
 192         start_pfn >>= PAGE_SHIFT;
 193
 194         bootmap_pfn = start_pfn;
 195
 196         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 197
 198         max_low_pfn = max_pfn;
 199         highstart_pfn = highend_pfn = max_pfn;
 200
 201         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 202                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 203                 max_low_pfn = calc_max_low_pfn();
 204                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 205                     calc_highpages() >> (20 - PAGE_SHIFT));
 206         }
 207
 208 #ifdef CONFIG_BLK_DEV_INITRD
 209         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 210         if (sparc_ramdisk_image) {
 211                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 212                         sparc_ramdisk_image -= KERNBASE;
 213                 initrd_start = sparc_ramdisk_image + phys_base;
 214                 initrd_end = initrd_start + sparc_ramdisk_size;
 215                 if (initrd_end > end_of_phys_memory) {
 216                         printk(KERN_CRIT "initrd extends beyond end of memory "
 217                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 218                                initrd_end, end_of_phys_memory);
 219                         initrd_start = 0;
 220                 }
 221                 if (initrd_start) {
 222                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 223                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 224                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 225                 }
 226         }
 227 #endif
 228         /* Initialize the boot-time allocator. */
 229         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 230                                          max_low_pfn);
 231
 232         /* Now register the available physical memory with the
 233          * allocator.
 234          */
 235         *pages_avail = 0;
 236         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 237                 unsigned long curr_pfn, last_pfn;
 238
 239                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 240                 if (curr_pfn >= max_low_pfn)
 241                         break;
 242
 243                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 244                 if (last_pfn > max_low_pfn)
 245                         last_pfn = max_low_pfn;
 246
 247                 /*
 248                  * .. finally, did all the rounding and playing
 249                  * around just make the area go away?
 250                  */
 251                 if (last_pfn <= curr_pfn)
 252                         continue;
 253
 254                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 255                 *pages_avail += last_pfn - curr_pfn;
 256
 257                 free_bootmem(sp_banks[i].base_addr, size);
 258         }
 259
 260 #ifdef CONFIG_BLK_DEV_INITRD
 261         if (initrd_start) {
 262                 /* Reserve the initrd image area. */
 263                 size = initrd_end - initrd_start;
 264                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 265                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 266
 267                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 268                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 269         }
 270 #endif
 271         /* Reserve the kernel text/data/bss. */
 272         size = (start_pfn << PAGE_SHIFT) - phys_base;
 273         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 274         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 275
 276         /* Reserve the bootmem map.   We do not account for it
 277          * in pages_avail because we will release that memory
 278          * in free_all_bootmem.
 279          */
 280         size = bootmap_size;
 281         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 282         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 283
 284         return max_pfn;
 285 }
 286
 287 /*
 288  * check_pgt_cache
 289  *
 290  * This is called at the end of unmapping of VMA (zap_page_range),
 291  * to rescan the page cache for architecture specific things,
 292  * presumably something like sun4/sun4c PMEGs. Most architectures
 293  * define check_pgt_cache empty.
 294  *
 295  * We simply copy the 2.4 implementation for now.
 296  */
 297 static int pgt_cache_water[2] = { 25, 50 };
 298
 299 void check_pgt_cache(void)
 300 {
 301         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
 302 }
 303
 304 /*
 305  * paging_init() sets up the page tables: We call the MMU specific
 306  * init routine based upon the Sun model type on the Sparc.
 307  *
 308  */
 309 extern void sun4c_paging_init(void);
 310 extern void srmmu_paging_init(void);
 311 extern void device_scan(void);
 312
 313 pgprot_t PAGE_SHARED __read_mostly;
 314 EXPORT_SYMBOL(PAGE_SHARED);
 315
 316 void __init paging_init(void)
 317 {
 318         switch(sparc_cpu_model) {
 319         case sun4c:
 320         case sun4e:
 321         case sun4:
 322                 sun4c_paging_init();
 323                 sparc_unmapped_base = 0xe0000000;
 324                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
 325                 break;
 326         case sun4m:
 327         case sun4d:
 328                 srmmu_paging_init();
 329                 sparc_unmapped_base = 0x50000000;
 330                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
 331                 break;
 332         default:
 333                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
 334                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
 335                 prom_printf("paging_init: Halting...\n");
 336                 prom_halt();
 337         };
 338
 339         /* Initialize the protection map with non-constant, MMU dependent values. */
 340         protection_map[0] = PAGE_NONE;
 341         protection_map[1] = PAGE_READONLY;
 342         protection_map[2] = PAGE_COPY;
 343         protection_map[3] = PAGE_COPY;
 344         protection_map[4] = PAGE_READONLY;
 345         protection_map[5] = PAGE_READONLY;
 346         protection_map[6] = PAGE_COPY;
 347         protection_map[7] = PAGE_COPY;
 348         protection_map[8] = PAGE_NONE;
 349         protection_map[9] = PAGE_READONLY;
 350         protection_map[10] = PAGE_SHARED;
 351         protection_map[11] = PAGE_SHARED;
 352         protection_map[12] = PAGE_READONLY;
 353         protection_map[13] = PAGE_READONLY;
 354         protection_map[14] = PAGE_SHARED;
 355         protection_map[15] = PAGE_SHARED;
 356         btfixup();
 357         prom_build_devicetree();
 358         device_scan();
 359 }
 360
 361 static void __init taint_real_pages(void)
 362 {
 363         int i;
 364
 365         for (i = 0; sp_banks[i].num_bytes; i++) {
 366                 unsigned long start, end;
 367
 368                 start = sp_banks[i].base_addr;
 369                 end = start + sp_banks[i].num_bytes;
 370
 371                 while (start < end) {
 372                         set_bit(start >> 20, sparc_valid_addr_bitmap);
 373                         start += PAGE_SIZE;
 374                 }
 375         }
 376 }
 377
 378 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 379 {
 380         unsigned long tmp;
 381
 382 #ifdef CONFIG_DEBUG_HIGHMEM
 383         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 384 #endif
 385
 386         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
 387                 struct page *page = pfn_to_page(tmp);
 388
 389                 ClearPageReserved(page);
 390                 init_page_count(page);
 391                 __free_page(page);
 392                 totalhigh_pages++;
 393         }
 394 }
 395
 396 void __init mem_init(void)
 397 {
 398         int codepages = 0;
 399         int datapages = 0;
 400         int initpages = 0;
 401         int reservedpages = 0;
 402         int i;
 403
 404         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 405                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
 406                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 407                        PKMAP_BASE,
 408                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 409                        FIXADDR_START);
 410                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 411                 prom_halt();
 412         }
 413
 414
 415         /* Saves us work later. */
 416         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
 417
 418         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 419         i += 1;
 420         sparc_valid_addr_bitmap = (unsigned long *)
 421                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 422
 423         if (sparc_valid_addr_bitmap == NULL) {
 424                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 425                 prom_halt();
 426         }
 427         memset(sparc_valid_addr_bitmap, 0, i << 2);
 428
 429         taint_real_pages();
 430
 431         max_mapnr = last_valid_pfn - pfn_base;
 432         high_memory = __va(max_low_pfn << PAGE_SHIFT);
 433
 434         totalram_pages = free_all_bootmem();
 435
 436         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 437                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 438                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 439
 440                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
 441
 442                 if (end_pfn <= highstart_pfn)
 443                         continue;
 444
 445                 if (start_pfn < highstart_pfn)
 446                         start_pfn = highstart_pfn;
 447
 448                 map_high_region(start_pfn, end_pfn);
 449         }
 450
 451         totalram_pages += totalhigh_pages;
 452
 453         codepages = (((unsigned long) &etext) - ((unsigned long)&_start));
 454         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
 455         datapages = (((unsigned long) &edata) - ((unsigned long)&etext));
 456         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
 457         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
 458         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 459
 460         /* Ignore memory holes for the purpose of counting reserved pages */
 461         for (i=0; i < max_low_pfn; i++)
 462                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
 463                     && PageReserved(pfn_to_page(i)))
 464                         reservedpages++;
 465
 466         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
 467                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 468                num_physpages << (PAGE_SHIFT - 10),
 469                codepages << (PAGE_SHIFT-10),
 470                reservedpages << (PAGE_SHIFT - 10),
 471                datapages << (PAGE_SHIFT-10),
 472                initpages << (PAGE_SHIFT-10),
 473                totalhigh_pages << (PAGE_SHIFT-10));
 474 }
 475
 476 void free_initmem (void)
 477 {
 478         unsigned long addr;
 479
 480         addr = (unsigned long)(&__init_begin);
 481         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 482                 struct page *p;
 483
 484                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
 485                 p = virt_to_page(addr);
 486
 487                 ClearPageReserved(p);
 488                 init_page_count(p);
 489                 __free_page(p);
 490                 totalram_pages++;
 491                 num_physpages++;
 492         }
 493         printk(KERN_INFO "Freeing unused kernel memory: %dk freed\n",
 494                 (&__init_end - &__init_begin) >> 10);
 495 }
 496
 497 #ifdef CONFIG_BLK_DEV_INITRD
 498 void free_initrd_mem(unsigned long start, unsigned long end)
 499 {
 500         if (start < end)
 501                 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
 502                         (end - start) >> 10);
 503         for (; start < end; start += PAGE_SIZE) {
 504                 struct page *p;
 505
 506                 memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
 507                 p = virt_to_page(start);
 508
 509                 ClearPageReserved(p);
 510                 init_page_count(p);
 511                 __free_page(p);
 512                 totalram_pages++;
 513                 num_physpages++;
 514         }
 515 }
 516 #endif
 517
 518 void sparc_flush_page_to_ram(struct page *page)
 519 {
 520         unsigned long vaddr = (unsigned long)page_address(page);
 521
 522         if (vaddr)
 523                 __flush_page_to_ram(vaddr);
 524 }