arch/arm/mm/init.c

   1 /*
   2  *  linux/arch/arm/mm/init.c
   3  *
   4  *  Copyright (C) 1995-2005 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <linux/swap.h>
  13 #include <linux/init.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/mman.h>
  16 #include <linux/nodemask.h>
  17 #include <linux/initrd.h>
  18 #include <linux/highmem.h>
  19
  20 #include <asm/mach-types.h>
  21 #include <asm/sections.h>
  22 #include <asm/setup.h>
  23 #include <asm/sizes.h>
  24 #include <asm/tlb.h>
  25
  26 #include <asm/mach/arch.h>
  27 #include <asm/mach/map.h>
  28
  29 #include "mm.h"
  30
  31 static unsigned long phys_initrd_start __initdata = 0;
  32 static unsigned long phys_initrd_size __initdata = 0;
  33
  34 static void __init early_initrd(char **p)
  35 {
  36         unsigned long start, size;
  37
  38         start = memparse(*p, p);
  39         if (**p == ',') {
  40                 size = memparse((*p) + 1, p);
  41
  42                 phys_initrd_start = start;
  43                 phys_initrd_size = size;
  44         }
  45 }
  46 __early_param("initrd=", early_initrd);
  47
  48 static int __init parse_tag_initrd(const struct tag *tag)
  49 {
  50         printk(KERN_WARNING "ATAG_INITRD is deprecated; "
  51                 "please update your bootloader.\n");
  52         phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
  53         phys_initrd_size = tag->u.initrd.size;
  54         return 0;
  55 }
  56
  57 __tagtable(ATAG_INITRD, parse_tag_initrd);
  58
  59 static int __init parse_tag_initrd2(const struct tag *tag)
  60 {
  61         phys_initrd_start = tag->u.initrd.start;
  62         phys_initrd_size = tag->u.initrd.size;
  63         return 0;
  64 }
  65
  66 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
  67
  68 /*
  69  * This keeps memory configuration data used by a couple memory
  70  * initialization functions, as well as show_mem() for the skipping
  71  * of holes in the memory map.  It is populated by arm_add_memory().
  72  */
  73 struct meminfo meminfo;
  74
  75 void show_mem(void)
  76 {
  77         int free = 0, total = 0, reserved = 0;
  78         int shared = 0, cached = 0, slab = 0, node, i;
  79         struct meminfo * mi = &meminfo;
  80
  81         printk("Mem-info:\n");
  82         show_free_areas();
  83         for_each_online_node(node) {
  84                 pg_data_t *n = NODE_DATA(node);
  85                 struct page *map = pgdat_page_nr(n, 0) - n->node_start_pfn;
  86
  87                 for_each_nodebank (i,mi,node) {
  88                         struct membank *bank = &mi->bank[i];
  89                         unsigned int pfn1, pfn2;
  90                         struct page *page, *end;
  91
  92                         pfn1 = bank_pfn_start(bank);
  93                         pfn2 = bank_pfn_end(bank);
  94
  95                         page = map + pfn1;
  96                         end  = map + pfn2;
  97
  98                         do {
  99                                 total++;
 100                                 if (PageReserved(page))
 101                                         reserved++;
 102                                 else if (PageSwapCache(page))
 103                                         cached++;
 104                                 else if (PageSlab(page))
 105                                         slab++;
 106                                 else if (!page_count(page))
 107                                         free++;
 108                                 else
 109                                         shared += page_count(page) - 1;
 110                                 page++;
 111                         } while (page < end);
 112                 }
 113         }
 114
 115         printk("%d pages of RAM\n", total);
 116         printk("%d free pages\n", free);
 117         printk("%d reserved pages\n", reserved);
 118         printk("%d slab pages\n", slab);
 119         printk("%d pages shared\n", shared);
 120         printk("%d pages swap cached\n", cached);
 121 }
 122
 123 /*
 124  * FIXME: We really want to avoid allocating the bootmap bitmap
 125  * over the top of the initrd.  Hopefully, this is located towards
 126  * the start of a bank, so if we allocate the bootmap bitmap at
 127  * the end, we won't clash.
 128  */
 129 static unsigned int __init
 130 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
 131 {
 132         unsigned int start_pfn, i, bootmap_pfn;
 133
 134         start_pfn   = PAGE_ALIGN(__pa(_end)) >> PAGE_SHIFT;
 135         bootmap_pfn = 0;
 136
 137         for_each_nodebank(i, mi, node) {
 138                 struct membank *bank = &mi->bank[i];
 139                 unsigned int start, end;
 140
 141                 start = bank_pfn_start(bank);
 142                 end   = bank_pfn_end(bank);
 143
 144                 if (end < start_pfn)
 145                         continue;
 146
 147                 if (start < start_pfn)
 148                         start = start_pfn;
 149
 150                 if (end <= start)
 151                         continue;
 152
 153                 if (end - start >= bootmap_pages) {
 154                         bootmap_pfn = start;
 155                         break;
 156                 }
 157         }
 158
 159         if (bootmap_pfn == 0)
 160                 BUG();
 161
 162         return bootmap_pfn;
 163 }
 164
 165 static int __init check_initrd(struct meminfo *mi)
 166 {
 167         int initrd_node = -2;
 168 #ifdef CONFIG_BLK_DEV_INITRD
 169         unsigned long end = phys_initrd_start + phys_initrd_size;
 170
 171         /*
 172          * Make sure that the initrd is within a valid area of
 173          * memory.
 174          */
 175         if (phys_initrd_size) {
 176                 unsigned int i;
 177
 178                 initrd_node = -1;
 179
 180                 for (i = 0; i < mi->nr_banks; i++) {
 181                         struct membank *bank = &mi->bank[i];
 182                         if (bank_phys_start(bank) <= phys_initrd_start &&
 183                             end <= bank_phys_end(bank))
 184                                 initrd_node = bank->node;
 185                 }
 186         }
 187
 188         if (initrd_node == -1) {
 189                 printk(KERN_ERR "INITRD: 0x%08lx+0x%08lx extends beyond "
 190                        "physical memory - disabling initrd\n",
 191                        phys_initrd_start, phys_initrd_size);
 192                 phys_initrd_start = phys_initrd_size = 0;
 193         }
 194 #endif
 195
 196         return initrd_node;
 197 }
 198
 199 static inline void map_memory_bank(struct membank *bank)
 200 {
 201 #ifdef CONFIG_MMU
 202         struct map_desc map;
 203
 204         map.pfn = bank_pfn_start(bank);
 205         map.virtual = __phys_to_virt(bank_phys_start(bank));
 206         map.length = bank_phys_size(bank);
 207         map.type = MT_MEMORY;
 208
 209         create_mapping(&map);
 210 #endif
 211 }
 212
 213 static unsigned long __init bootmem_init_node(int node, struct meminfo *mi)
 214 {
 215         unsigned long start_pfn, end_pfn, boot_pfn;
 216         unsigned int boot_pages;
 217         pg_data_t *pgdat;
 218         int i;
 219
 220         start_pfn = -1UL;
 221         end_pfn = 0;
 222
 223         /*
 224          * Calculate the pfn range, and map the memory banks for this node.
 225          */
 226         for_each_nodebank(i, mi, node) {
 227                 struct membank *bank = &mi->bank[i];
 228                 unsigned long start, end;
 229
 230                 start = bank_pfn_start(bank);
 231                 end = bank_pfn_end(bank);
 232
 233                 if (start_pfn > start)
 234                         start_pfn = start;
 235                 if (end_pfn < end)
 236                         end_pfn = end;
 237
 238                 map_memory_bank(bank);
 239         }
 240
 241         /*
 242          * If there is no memory in this node, ignore it.
 243          */
 244         if (end_pfn == 0)
 245                 return end_pfn;
 246
 247         /*
 248          * Allocate the bootmem bitmap page.
 249          */
 250         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 251         boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
 252
 253         /*
 254          * Initialise the bootmem allocator for this node, handing the
 255          * memory banks over to bootmem.
 256          */
 257         node_set_online(node);
 258         pgdat = NODE_DATA(node);
 259         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 260
 261         for_each_nodebank(i, mi, node) {
 262                 struct membank *bank = &mi->bank[i];
 263                 free_bootmem_node(pgdat, bank_phys_start(bank), bank_phys_size(bank));
 264                 memory_present(node, bank_pfn_start(bank), bank_pfn_end(bank));
 265         }
 266
 267         /*
 268          * Reserve the bootmem bitmap for this node.
 269          */
 270         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 271                              boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
 272
 273         return end_pfn;
 274 }
 275
 276 static void __init bootmem_reserve_initrd(int node)
 277 {
 278 #ifdef CONFIG_BLK_DEV_INITRD
 279         pg_data_t *pgdat = NODE_DATA(node);
 280         int res;
 281
 282         res = reserve_bootmem_node(pgdat, phys_initrd_start,
 283                              phys_initrd_size, BOOTMEM_EXCLUSIVE);
 284
 285         if (res == 0) {
 286                 initrd_start = __phys_to_virt(phys_initrd_start);
 287                 initrd_end = initrd_start + phys_initrd_size;
 288         } else {
 289                 printk(KERN_ERR
 290                         "INITRD: 0x%08lx+0x%08lx overlaps in-use "
 291                         "memory region - disabling initrd\n",
 292                         phys_initrd_start, phys_initrd_size);
 293         }
 294 #endif
 295 }
 296
 297 static void __init bootmem_free_node(int node, struct meminfo *mi)
 298 {
 299         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 300         unsigned long start_pfn, end_pfn;
 301         pg_data_t *pgdat = NODE_DATA(node);
 302         int i;
 303
 304         start_pfn = pgdat->bdata->node_min_pfn;
 305         end_pfn = pgdat->bdata->node_low_pfn;
 306
 307         /*
 308          * initialise the zones within this node.
 309          */
 310         memset(zone_size, 0, sizeof(zone_size));
 311         memset(zhole_size, 0, sizeof(zhole_size));
 312
 313         /*
 314          * The size of this node has already been determined.  If we need
 315          * to do anything fancy with the allocation of this memory to the
 316          * zones, now is the time to do it.
 317          */
 318         zone_size[0] = end_pfn - start_pfn;
 319
 320         /*
 321          * For each bank in this node, calculate the size of the holes.
 322          *  holes = node_size - sum(bank_sizes_in_node)
 323          */
 324         zhole_size[0] = zone_size[0];
 325         for_each_nodebank(i, mi, node)
 326                 zhole_size[0] -= bank_pfn_size(&mi->bank[i]);
 327
 328         /*
 329          * Adjust the sizes according to any special requirements for
 330          * this machine type.
 331          */
 332         arch_adjust_zones(node, zone_size, zhole_size);
 333
 334         free_area_init_node(node, zone_size, start_pfn, zhole_size);
 335 }
 336
 337 void __init bootmem_init(void)
 338 {
 339         struct meminfo *mi = &meminfo;
 340         unsigned long memend_pfn = 0;
 341         int node, initrd_node;
 342
 343         /*
 344          * Locate which node contains the ramdisk image, if any.
 345          */
 346         initrd_node = check_initrd(mi);
 347
 348         /*
 349          * Run through each node initialising the bootmem allocator.
 350          */
 351         for_each_node(node) {
 352                 unsigned long end_pfn = bootmem_init_node(node, mi);
 353
 354                 /*
 355                  * Reserve any special node zero regions.
 356                  */
 357                 if (node == 0)
 358                         reserve_node_zero(NODE_DATA(node));
 359
 360                 /*
 361                  * If the initrd is in this node, reserve its memory.
 362                  */
 363                 if (node == initrd_node)
 364                         bootmem_reserve_initrd(node);
 365
 366                 /*
 367                  * Remember the highest memory PFN.
 368                  */
 369                 if (end_pfn > memend_pfn)
 370                         memend_pfn = end_pfn;
 371         }
 372
 373         /*
 374          * sparse_init() needs the bootmem allocator up and running.
 375          */
 376         sparse_init();
 377
 378         /*
 379          * Now free memory in each node - free_area_init_node needs
 380          * the sparse mem_map arrays initialized by sparse_init()
 381          * for memmap_init_zone(), otherwise all PFNs are invalid.
 382          */
 383         for_each_node(node)
 384                 bootmem_free_node(node, mi);
 385
 386         high_memory = __va((memend_pfn << PAGE_SHIFT) - 1) + 1;
 387
 388         /*
 389          * This doesn't seem to be used by the Linux memory manager any
 390          * more, but is used by ll_rw_block.  If we can get rid of it, we
 391          * also get rid of some of the stuff above as well.
 392          *
 393          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 394          * the system, not the maximum PFN.
 395          */
 396         max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 397 }
 398
 399 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
 400 {
 401         unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
 402
 403         for (; pfn < end; pfn++) {
 404                 struct page *page = pfn_to_page(pfn);
 405                 ClearPageReserved(page);
 406                 init_page_count(page);
 407                 __free_page(page);
 408                 pages++;
 409         }
 410
 411         if (size && s)
 412                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 413
 414         return pages;
 415 }
 416
 417 static inline void
 418 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 419 {
 420         struct page *start_pg, *end_pg;
 421         unsigned long pg, pgend;
 422
 423         /*
 424          * Convert start_pfn/end_pfn to a struct page pointer.
 425          */
 426         start_pg = pfn_to_page(start_pfn);
 427         end_pg = pfn_to_page(end_pfn);
 428
 429         /*
 430          * Convert to physical addresses, and
 431          * round start upwards and end downwards.
 432          */
 433         pg = PAGE_ALIGN(__pa(start_pg));
 434         pgend = __pa(end_pg) & PAGE_MASK;
 435
 436         /*
 437          * If there are free pages between these,
 438          * free the section of the memmap array.
 439          */
 440         if (pg < pgend)
 441                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 442 }
 443
 444 /*
 445  * The mem_map array can get very big.  Free the unused area of the memory map.
 446  */
 447 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 448 {
 449         unsigned long bank_start, prev_bank_end = 0;
 450         unsigned int i;
 451
 452         /*
 453          * [FIXME] This relies on each bank being in address order.  This
 454          * may not be the case, especially if the user has provided the
 455          * information on the command line.
 456          */
 457         for_each_nodebank(i, mi, node) {
 458                 struct membank *bank = &mi->bank[i];
 459
 460                 bank_start = bank_pfn_start(bank);
 461                 if (bank_start < prev_bank_end) {
 462                         printk(KERN_ERR "MEM: unordered memory banks.  "
 463                                 "Not freeing memmap.\n");
 464                         break;
 465                 }
 466
 467                 /*
 468                  * If we had a previous bank, and there is a space
 469                  * between the current bank and the previous, free it.
 470                  */
 471                 if (prev_bank_end && prev_bank_end != bank_start)
 472                         free_memmap(node, prev_bank_end, bank_start);
 473
 474                 prev_bank_end = bank_pfn_end(bank);
 475         }
 476 }
 477
 478 /*
 479  * mem_init() marks the free areas in the mem_map and tells us how much
 480  * memory is free.  This is done after various parts of the system have
 481  * claimed their memory after the kernel image.
 482  */
 483 void __init mem_init(void)
 484 {
 485         unsigned int codesize, datasize, initsize;
 486         int i, node;
 487
 488 #ifndef CONFIG_DISCONTIGMEM
 489         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 490 #endif
 491
 492         /* this will put all unused low memory onto the freelists */
 493         for_each_online_node(node) {
 494                 pg_data_t *pgdat = NODE_DATA(node);
 495
 496                 free_unused_memmap_node(node, &meminfo);
 497
 498                 if (pgdat->node_spanned_pages != 0)
 499                         totalram_pages += free_all_bootmem_node(pgdat);
 500         }
 501
 502 #ifdef CONFIG_SA1111
 503         /* now that our DMA memory is actually so designated, we can free it */
 504         totalram_pages += free_area(PHYS_PFN_OFFSET,
 505                                     __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
 506 #endif
 507
 508 #ifdef CONFIG_HIGHMEM
 509         /* set highmem page free */
 510         for_each_online_node(node) {
 511                 for_each_nodebank (i, &meminfo, node) {
 512                         unsigned long start = bank_pfn_start(&meminfo.bank[i]);
 513                         unsigned long end = bank_pfn_end(&meminfo.bank[i]);
 514                         if (start >= max_low_pfn + PHYS_PFN_OFFSET)
 515                                 totalhigh_pages += free_area(start, end, NULL);
 516                 }
 517         }
 518         totalram_pages += totalhigh_pages;
 519 #endif
 520
 521         /*
 522          * Since our memory may not be contiguous, calculate the
 523          * real number of pages we have in this system
 524          */
 525         printk(KERN_INFO "Memory:");
 526         num_physpages = 0;
 527         for (i = 0; i < meminfo.nr_banks; i++) {
 528                 num_physpages += bank_pfn_size(&meminfo.bank[i]);
 529                 printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
 530         }
 531         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 532
 533         codesize = _etext - _text;
 534         datasize = _end - _data;
 535         initsize = __init_end - __init_begin;
 536
 537         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 538                 "%dK data, %dK init, %luK highmem)\n",
 539                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 540                 codesize >> 10, datasize >> 10, initsize >> 10,
 541                 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 542
 543         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 544                 extern int sysctl_overcommit_memory;
 545                 /*
 546                  * On a machine this small we won't get
 547                  * anywhere without overcommit, so turn
 548                  * it on by default.
 549                  */
 550                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 551         }
 552 }
 553
 554 void free_initmem(void)
 555 {
 556         if (!machine_is_integrator() && !machine_is_cintegrator())
 557                 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
 558                                             __phys_to_pfn(__pa(__init_end)),
 559                                             "init");
 560 }
 561
 562 #ifdef CONFIG_BLK_DEV_INITRD
 563
 564 static int keep_initrd;
 565
 566 void free_initrd_mem(unsigned long start, unsigned long end)
 567 {
 568         if (!keep_initrd)
 569                 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
 570                                             __phys_to_pfn(__pa(end)),
 571                                             "initrd");
 572 }
 573
 574 static int __init keepinitrd_setup(char *__unused)
 575 {
 576         keep_initrd = 1;
 577         return 1;
 578 }
 579
 580 __setup("keepinitrd", keepinitrd_setup);
 581 #endif