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