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/sections.h>
  29 #include <asm/system.h>
  30 #include <asm/vac-ops.h>
  31 #include <asm/page.h>
  32 #include <asm/pgtable.h>
  33 #include <asm/vaddrs.h>
  34 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  35 #include <asm/tlb.h>
  36 #include <asm/prom.h>
  37
  38 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  39
  40 unsigned long *sparc_valid_addr_bitmap;
  41 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  42
  43 unsigned long phys_base;
  44 EXPORT_SYMBOL(phys_base);
  45
  46 unsigned long pfn_base;
  47 EXPORT_SYMBOL(pfn_base);
  48
  49 unsigned long page_kernel;
  50 EXPORT_SYMBOL(page_kernel);
  51
  52 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  53 unsigned long sparc_unmapped_base;
  54
  55 struct pgtable_cache_struct pgt_quicklists;
  56
  57 /* Initial ramdisk setup */
  58 extern unsigned int sparc_ramdisk_image;
  59 extern unsigned int sparc_ramdisk_size;
  60
  61 unsigned long highstart_pfn, highend_pfn;
  62
  63 pte_t *kmap_pte;
  64 pgprot_t kmap_prot;
  65
  66 #define kmap_get_fixmap_pte(vaddr) \
  67         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
  68
  69 void __init kmap_init(void)
  70 {
  71         /* cache the first kmap pte */
  72         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
  73         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
  74 }
  75
  76 void show_mem(void)
  77 {
  78         printk("Mem-info:\n");
  79         show_free_areas();
  80         printk("Free swap:       %6ldkB\n",
  81                nr_swap_pages << (PAGE_SHIFT-10));
  82         printk("%ld pages of RAM\n", totalram_pages);
  83         printk("%ld free pages\n", nr_free_pages());
  84 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
  85         printk("%ld pages in page table cache\n",pgtable_cache_size);
  86 #ifndef CONFIG_SMP
  87         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
  88                 printk("%ld entries in page dir cache\n",pgd_cache_size);
  89 #endif
  90 #endif
  91 }
  92
  93 void __init sparc_context_init(int numctx)
  94 {
  95         int ctx;
  96
  97         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
  98
  99         for(ctx = 0; ctx < numctx; ctx++) {
 100                 struct ctx_list *clist;
 101
 102                 clist = (ctx_list_pool + ctx);
 103                 clist->ctx_number = ctx;
 104                 clist->ctx_mm = NULL;
 105         }
 106         ctx_free.next = ctx_free.prev = &ctx_free;
 107         ctx_used.next = ctx_used.prev = &ctx_used;
 108         for(ctx = 0; ctx < numctx; ctx++)
 109                 add_to_free_ctxlist(ctx_list_pool + ctx);
 110 }
 111
 112 extern unsigned long cmdline_memory_size;
 113 unsigned long last_valid_pfn;
 114
 115 unsigned long calc_highpages(void)
 116 {
 117         int i;
 118         int nr = 0;
 119
 120         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 121                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 122                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 123
 124                 if (end_pfn <= max_low_pfn)
 125                         continue;
 126
 127                 if (start_pfn < max_low_pfn)
 128                         start_pfn = max_low_pfn;
 129
 130                 nr += end_pfn - start_pfn;
 131         }
 132
 133         return nr;
 134 }
 135
 136 static unsigned long calc_max_low_pfn(void)
 137 {
 138         int i;
 139         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 140         unsigned long curr_pfn, last_pfn;
 141
 142         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
 143         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
 144                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 145
 146                 if (curr_pfn >= tmp) {
 147                         if (last_pfn < tmp)
 148                                 tmp = last_pfn;
 149                         break;
 150                 }
 151
 152                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 153         }
 154
 155         return tmp;
 156 }
 157
 158 unsigned long __init bootmem_init(unsigned long *pages_avail)
 159 {
 160         unsigned long bootmap_size, start_pfn;
 161         unsigned long end_of_phys_memory = 0UL;
 162         unsigned long bootmap_pfn, bytes_avail, size;
 163         int i;
 164
 165         bytes_avail = 0UL;
 166         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 167                 end_of_phys_memory = sp_banks[i].base_addr +
 168                         sp_banks[i].num_bytes;
 169                 bytes_avail += sp_banks[i].num_bytes;
 170                 if (cmdline_memory_size) {
 171                         if (bytes_avail > cmdline_memory_size) {
 172                                 unsigned long slack = bytes_avail - cmdline_memory_size;
 173
 174                                 bytes_avail -= slack;
 175                                 end_of_phys_memory -= slack;
 176
 177                                 sp_banks[i].num_bytes -= slack;
 178                                 if (sp_banks[i].num_bytes == 0) {
 179                                         sp_banks[i].base_addr = 0xdeadbeef;
 180                                 } else {
 181                                         sp_banks[i+1].num_bytes = 0;
 182                                         sp_banks[i+1].base_addr = 0xdeadbeef;
 183                                 }
 184                                 break;
 185                         }
 186                 }
 187         }
 188
 189         /* Start with page aligned address of last symbol in kernel
 190          * image.
 191          */
 192         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 193
 194         /* Now shift down to get the real physical page frame number. */
 195         start_pfn >>= PAGE_SHIFT;
 196
 197         bootmap_pfn = start_pfn;
 198
 199         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 200
 201         max_low_pfn = max_pfn;
 202         highstart_pfn = highend_pfn = max_pfn;
 203
 204         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 205                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 206                 max_low_pfn = calc_max_low_pfn();
 207                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 208                     calc_highpages() >> (20 - PAGE_SHIFT));
 209         }
 210
 211 #ifdef CONFIG_BLK_DEV_INITRD
 212         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 213         if (sparc_ramdisk_image) {
 214                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 215                         sparc_ramdisk_image -= KERNBASE;
 216                 initrd_start = sparc_ramdisk_image + phys_base;
 217                 initrd_end = initrd_start + sparc_ramdisk_size;
 218                 if (initrd_end > end_of_phys_memory) {
 219                         printk(KERN_CRIT "initrd extends beyond end of memory "
 220                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 221                                initrd_end, end_of_phys_memory);
 222                         initrd_start = 0;
 223                 }
 224                 if (initrd_start) {
 225                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 226                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 227                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 228                 }
 229         }
 230 #endif
 231         /* Initialize the boot-time allocator. */
 232         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 233                                          max_low_pfn);
 234
 235         /* Now register the available physical memory with the
 236          * allocator.
 237          */
 238         *pages_avail = 0;
 239         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 240                 unsigned long curr_pfn, last_pfn;
 241
 242                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 243                 if (curr_pfn >= max_low_pfn)
 244                         break;
 245
 246                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 247                 if (last_pfn > max_low_pfn)
 248                         last_pfn = max_low_pfn;
 249
 250                 /*
 251                  * .. finally, did all the rounding and playing
 252                  * around just make the area go away?
 253                  */
 254                 if (last_pfn <= curr_pfn)
 255                         continue;
 256
 257                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 258                 *pages_avail += last_pfn - curr_pfn;
 259
 260                 free_bootmem(sp_banks[i].base_addr, size);
 261         }
 262
 263 #ifdef CONFIG_BLK_DEV_INITRD
 264         if (initrd_start) {
 265                 /* Reserve the initrd image area. */
 266                 size = initrd_end - initrd_start;
 267                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 268                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 269
 270                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 271                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
 272         }
 273 #endif
 274         /* Reserve the kernel text/data/bss. */
 275         size = (start_pfn << PAGE_SHIFT) - phys_base;
 276         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 277         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 278
 279         /* Reserve the bootmem map.   We do not account for it
 280          * in pages_avail because we will release that memory
 281          * in free_all_bootmem.
 282          */
 283         size = bootmap_size;
 284         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 285         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 286
 287         return max_pfn;
 288 }
 289
 290 /*
 291  * check_pgt_cache
 292  *
 293  * This is called at the end of unmapping of VMA (zap_page_range),
 294  * to rescan the page cache for architecture specific things,
 295  * presumably something like sun4/sun4c PMEGs. Most architectures
 296  * define check_pgt_cache empty.
 297  *
 298  * We simply copy the 2.4 implementation for now.
 299  */
 300 static int pgt_cache_water[2] = { 25, 50 };
 301
 302 void check_pgt_cache(void)
 303 {
 304         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
 305 }
 306
 307 /*
 308  * paging_init() sets up the page tables: We call the MMU specific
 309  * init routine based upon the Sun model type on the Sparc.
 310  *
 311  */
 312 extern void sun4c_paging_init(void);
 313 extern void srmmu_paging_init(void);
 314 extern void device_scan(void);
 315
 316 pgprot_t PAGE_SHARED __read_mostly;
 317 EXPORT_SYMBOL(PAGE_SHARED);
 318
 319 void __init paging_init(void)
 320 {
 321         switch(sparc_cpu_model) {
 322         case sun4c:
 323         case sun4e:
 324         case sun4:
 325                 sun4c_paging_init();
 326                 sparc_unmapped_base = 0xe0000000;
 327                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
 328                 break;
 329         case sun4m:
 330         case sun4d:
 331                 srmmu_paging_init();
 332                 sparc_unmapped_base = 0x50000000;
 333                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
 334                 break;
 335         default:
 336                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
 337                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
 338                 prom_printf("paging_init: Halting...\n");
 339                 prom_halt();
 340         };
 341
 342         /* Initialize the protection map with non-constant, MMU dependent values. */
 343         protection_map[0] = PAGE_NONE;
 344         protection_map[1] = PAGE_READONLY;
 345         protection_map[2] = PAGE_COPY;
 346         protection_map[3] = PAGE_COPY;
 347         protection_map[4] = PAGE_READONLY;
 348         protection_map[5] = PAGE_READONLY;
 349         protection_map[6] = PAGE_COPY;
 350         protection_map[7] = PAGE_COPY;
 351         protection_map[8] = PAGE_NONE;
 352         protection_map[9] = PAGE_READONLY;
 353         protection_map[10] = PAGE_SHARED;
 354         protection_map[11] = PAGE_SHARED;
 355         protection_map[12] = PAGE_READONLY;
 356         protection_map[13] = PAGE_READONLY;
 357         protection_map[14] = PAGE_SHARED;
 358         protection_map[15] = PAGE_SHARED;
 359         btfixup();
 360         prom_build_devicetree();
 361         of_fill_in_cpu_data();
 362         device_scan();
 363 }
 364
 365 static void __init taint_real_pages(void)
 366 {
 367         int i;
 368
 369         for (i = 0; sp_banks[i].num_bytes; i++) {
 370                 unsigned long start, end;
 371
 372                 start = sp_banks[i].base_addr;
 373                 end = start + sp_banks[i].num_bytes;
 374
 375                 while (start < end) {
 376                         set_bit(start >> 20, sparc_valid_addr_bitmap);
 377                         start += PAGE_SIZE;
 378                 }
 379         }
 380 }
 381
 382 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 383 {
 384         unsigned long tmp;
 385
 386 #ifdef CONFIG_DEBUG_HIGHMEM
 387         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 388 #endif
 389
 390         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
 391                 struct page *page = pfn_to_page(tmp);
 392
 393                 ClearPageReserved(page);
 394                 init_page_count(page);
 395                 __free_page(page);
 396                 totalhigh_pages++;
 397         }
 398 }
 399
 400 void __init mem_init(void)
 401 {
 402         int codepages = 0;
 403         int datapages = 0;
 404         int initpages = 0;
 405         int reservedpages = 0;
 406         int i;
 407
 408         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 409                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
 410                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 411                        PKMAP_BASE,
 412                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 413                        FIXADDR_START);
 414                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 415                 prom_halt();
 416         }
 417
 418
 419         /* Saves us work later. */
 420         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
 421
 422         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 423         i += 1;
 424         sparc_valid_addr_bitmap = (unsigned long *)
 425                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 426
 427         if (sparc_valid_addr_bitmap == NULL) {
 428                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 429                 prom_halt();
 430         }
 431         memset(sparc_valid_addr_bitmap, 0, i << 2);
 432
 433         taint_real_pages();
 434
 435         max_mapnr = last_valid_pfn - pfn_base;
 436         high_memory = __va(max_low_pfn << PAGE_SHIFT);
 437
 438         totalram_pages = free_all_bootmem();
 439
 440         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 441                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 442                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 443
 444                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
 445
 446                 if (end_pfn <= highstart_pfn)
 447                         continue;
 448
 449                 if (start_pfn < highstart_pfn)
 450                         start_pfn = highstart_pfn;
 451
 452                 map_high_region(start_pfn, end_pfn);
 453         }
 454
 455         totalram_pages += totalhigh_pages;
 456
 457         codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
 458         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
 459         datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
 460         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
 461         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
 462         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 463
 464         /* Ignore memory holes for the purpose of counting reserved pages */
 465         for (i=0; i < max_low_pfn; i++)
 466                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
 467                     && PageReserved(pfn_to_page(i)))
 468                         reservedpages++;
 469
 470         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
 471                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 472                num_physpages << (PAGE_SHIFT - 10),
 473                codepages << (PAGE_SHIFT-10),
 474                reservedpages << (PAGE_SHIFT - 10),
 475                datapages << (PAGE_SHIFT-10),
 476                initpages << (PAGE_SHIFT-10),
 477                totalhigh_pages << (PAGE_SHIFT-10));
 478 }
 479
 480 void free_initmem (void)
 481 {
 482         unsigned long addr;
 483         unsigned long freed;
 484
 485         addr = (unsigned long)(&__init_begin);
 486         freed = (unsigned long)(&__init_end) - addr;
 487         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 488                 struct page *p;
 489
 490                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
 491                 p = virt_to_page(addr);
 492
 493                 ClearPageReserved(p);
 494                 init_page_count(p);
 495                 __free_page(p);
 496                 totalram_pages++;
 497                 num_physpages++;
 498         }
 499         printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
 500                 freed >> 10);
 501 }
 502
 503 #ifdef CONFIG_BLK_DEV_INITRD
 504 void free_initrd_mem(unsigned long start, unsigned long end)
 505 {
 506         if (start < end)
 507                 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
 508                         (end - start) >> 10);
 509         for (; start < end; start += PAGE_SIZE) {
 510                 struct page *p;
 511
 512                 memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
 513                 p = virt_to_page(start);
 514
 515                 ClearPageReserved(p);
 516                 init_page_count(p);
 517                 __free_page(p);
 518                 totalram_pages++;
 519                 num_physpages++;
 520         }
 521 }
 522 #endif
 523
 524 void sparc_flush_page_to_ram(struct page *page)
 525 {
 526         unsigned long vaddr = (unsigned long)page_address(page);
 527
 528         if (vaddr)
 529                 __flush_page_to_ram(vaddr);
 530 }
 531 EXPORT_SYMBOL(sparc_flush_page_to_ram);