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/sort.h>
  19 #include <linux/highmem.h>
  20
  21 #include <asm/mach-types.h>
  22 #include <asm/sections.h>
  23 #include <asm/setup.h>
  24 #include <asm/sizes.h>
  25 #include <asm/tlb.h>
  26
  27 #include <asm/mach/arch.h>
  28 #include <asm/mach/map.h>
  29
  30 #include "mm.h"
  31
  32 static unsigned long phys_initrd_start __initdata = 0;
  33 static unsigned long phys_initrd_size __initdata = 0;
  34
  35 static void __init early_initrd(char **p)
  36 {
  37         unsigned long start, size;
  38
  39         start = memparse(*p, p);
  40         if (**p == ',') {
  41                 size = memparse((*p) + 1, p);
  42
  43                 phys_initrd_start = start;
  44                 phys_initrd_size = size;
  45         }
  46 }
  47 __early_param("initrd=", early_initrd);
  48
  49 static int __init parse_tag_initrd(const struct tag *tag)
  50 {
  51         printk(KERN_WARNING "ATAG_INITRD is deprecated; "
  52                 "please update your bootloader.\n");
  53         phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
  54         phys_initrd_size = tag->u.initrd.size;
  55         return 0;
  56 }
  57
  58 __tagtable(ATAG_INITRD, parse_tag_initrd);
  59
  60 static int __init parse_tag_initrd2(const struct tag *tag)
  61 {
  62         phys_initrd_start = tag->u.initrd.start;
  63         phys_initrd_size = tag->u.initrd.size;
  64         return 0;
  65 }
  66
  67 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
  68
  69 /*
  70  * This keeps memory configuration data used by a couple memory
  71  * initialization functions, as well as show_mem() for the skipping
  72  * of holes in the memory map.  It is populated by arm_add_memory().
  73  */
  74 struct meminfo meminfo;
  75
  76 void show_mem(void)
  77 {
  78         int free = 0, total = 0, reserved = 0;
  79         int shared = 0, cached = 0, slab = 0, node, i;
  80         struct meminfo * mi = &meminfo;
  81
  82         printk("Mem-info:\n");
  83         show_free_areas();
  84         for_each_online_node(node) {
  85                 pg_data_t *n = NODE_DATA(node);
  86                 struct page *map = pgdat_page_nr(n, 0) - n->node_start_pfn;
  87
  88                 for_each_nodebank (i,mi,node) {
  89                         struct membank *bank = &mi->bank[i];
  90                         unsigned int pfn1, pfn2;
  91                         struct page *page, *end;
  92
  93                         pfn1 = bank_pfn_start(bank);
  94                         pfn2 = bank_pfn_end(bank);
  95
  96                         page = map + pfn1;
  97                         end  = map + pfn2;
  98
  99                         do {
 100                                 total++;
 101                                 if (PageReserved(page))
 102                                         reserved++;
 103                                 else if (PageSwapCache(page))
 104                                         cached++;
 105                                 else if (PageSlab(page))
 106                                         slab++;
 107                                 else if (!page_count(page))
 108                                         free++;
 109                                 else
 110                                         shared += page_count(page) - 1;
 111                                 page++;
 112                         } while (page < end);
 113                 }
 114         }
 115
 116         printk("%d pages of RAM\n", total);
 117         printk("%d free pages\n", free);
 118         printk("%d reserved pages\n", reserved);
 119         printk("%d slab pages\n", slab);
 120         printk("%d pages shared\n", shared);
 121         printk("%d pages swap cached\n", cached);
 122 }
 123
 124 static void __init find_node_limits(int node, struct meminfo *mi,
 125         unsigned long *min, unsigned long *max_low, unsigned long *max_high)
 126 {
 127         int i;
 128
 129         *min = -1UL;
 130         *max_low = *max_high = 0;
 131
 132         for_each_nodebank(i, mi, node) {
 133                 struct membank *bank = &mi->bank[i];
 134                 unsigned long start, end;
 135
 136                 start = bank_pfn_start(bank);
 137                 end = bank_pfn_end(bank);
 138
 139                 if (*min > start)
 140                         *min = start;
 141                 if (*max_high < end)
 142                         *max_high = end;
 143                 if (bank->highmem)
 144                         continue;
 145                 if (*max_low < end)
 146                         *max_low = end;
 147         }
 148 }
 149
 150 /*
 151  * FIXME: We really want to avoid allocating the bootmap bitmap
 152  * over the top of the initrd.  Hopefully, this is located towards
 153  * the start of a bank, so if we allocate the bootmap bitmap at
 154  * the end, we won't clash.
 155  */
 156 static unsigned int __init
 157 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
 158 {
 159         unsigned int start_pfn, i, bootmap_pfn;
 160
 161         start_pfn   = PAGE_ALIGN(__pa(_end)) >> PAGE_SHIFT;
 162         bootmap_pfn = 0;
 163
 164         for_each_nodebank(i, mi, node) {
 165                 struct membank *bank = &mi->bank[i];
 166                 unsigned int start, end;
 167
 168                 start = bank_pfn_start(bank);
 169                 end   = bank_pfn_end(bank);
 170
 171                 if (end < start_pfn)
 172                         continue;
 173
 174                 if (start < start_pfn)
 175                         start = start_pfn;
 176
 177                 if (end <= start)
 178                         continue;
 179
 180                 if (end - start >= bootmap_pages) {
 181                         bootmap_pfn = start;
 182                         break;
 183                 }
 184         }
 185
 186         if (bootmap_pfn == 0)
 187                 BUG();
 188
 189         return bootmap_pfn;
 190 }
 191
 192 static int __init check_initrd(struct meminfo *mi)
 193 {
 194         int initrd_node = -2;
 195 #ifdef CONFIG_BLK_DEV_INITRD
 196         unsigned long end = phys_initrd_start + phys_initrd_size;
 197
 198         /*
 199          * Make sure that the initrd is within a valid area of
 200          * memory.
 201          */
 202         if (phys_initrd_size) {
 203                 unsigned int i;
 204
 205                 initrd_node = -1;
 206
 207                 for (i = 0; i < mi->nr_banks; i++) {
 208                         struct membank *bank = &mi->bank[i];
 209                         if (bank_phys_start(bank) <= phys_initrd_start &&
 210                             end <= bank_phys_end(bank))
 211                                 initrd_node = bank->node;
 212                 }
 213         }
 214
 215         if (initrd_node == -1) {
 216                 printk(KERN_ERR "INITRD: 0x%08lx+0x%08lx extends beyond "
 217                        "physical memory - disabling initrd\n",
 218                        phys_initrd_start, phys_initrd_size);
 219                 phys_initrd_start = phys_initrd_size = 0;
 220         }
 221 #endif
 222
 223         return initrd_node;
 224 }
 225
 226 static inline void map_memory_bank(struct membank *bank)
 227 {
 228 #ifdef CONFIG_MMU
 229         struct map_desc map;
 230
 231         map.pfn = bank_pfn_start(bank);
 232         map.virtual = __phys_to_virt(bank_phys_start(bank));
 233         map.length = bank_phys_size(bank);
 234         map.type = MT_MEMORY;
 235
 236         create_mapping(&map);
 237 #endif
 238 }
 239
 240 static void __init bootmem_init_node(int node, struct meminfo *mi,
 241         unsigned long start_pfn, unsigned long end_pfn)
 242 {
 243         unsigned long boot_pfn;
 244         unsigned int boot_pages;
 245         pg_data_t *pgdat;
 246         int i;
 247
 248         /*
 249          * Map the memory banks for this node.
 250          */
 251         for_each_nodebank(i, mi, node) {
 252                 struct membank *bank = &mi->bank[i];
 253
 254                 if (!bank->highmem)
 255                         map_memory_bank(bank);
 256         }
 257
 258         /*
 259          * Allocate the bootmem bitmap page.
 260          */
 261         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 262         boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
 263
 264         /*
 265          * Initialise the bootmem allocator for this node, handing the
 266          * memory banks over to bootmem.
 267          */
 268         node_set_online(node);
 269         pgdat = NODE_DATA(node);
 270         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 271
 272         for_each_nodebank(i, mi, node) {
 273                 struct membank *bank = &mi->bank[i];
 274                 if (!bank->highmem)
 275                         free_bootmem_node(pgdat, bank_phys_start(bank), bank_phys_size(bank));
 276                 memory_present(node, bank_pfn_start(bank), bank_pfn_end(bank));
 277         }
 278
 279         /*
 280          * Reserve the bootmem bitmap for this node.
 281          */
 282         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 283                              boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
 284 }
 285
 286 static void __init bootmem_reserve_initrd(int node)
 287 {
 288 #ifdef CONFIG_BLK_DEV_INITRD
 289         pg_data_t *pgdat = NODE_DATA(node);
 290         int res;
 291
 292         res = reserve_bootmem_node(pgdat, phys_initrd_start,
 293                              phys_initrd_size, BOOTMEM_EXCLUSIVE);
 294
 295         if (res == 0) {
 296                 initrd_start = __phys_to_virt(phys_initrd_start);
 297                 initrd_end = initrd_start + phys_initrd_size;
 298         } else {
 299                 printk(KERN_ERR
 300                         "INITRD: 0x%08lx+0x%08lx overlaps in-use "
 301                         "memory region - disabling initrd\n",
 302                         phys_initrd_start, phys_initrd_size);
 303         }
 304 #endif
 305 }
 306
 307 static void __init bootmem_free_node(int node, struct meminfo *mi)
 308 {
 309         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 310         unsigned long min, max_low, max_high;
 311         int i;
 312
 313         find_node_limits(node, mi, &min, &max_low, &max_high);
 314
 315         /*
 316          * initialise the zones within this node.
 317          */
 318         memset(zone_size, 0, sizeof(zone_size));
 319
 320         /*
 321          * The size of this node has already been determined.  If we need
 322          * to do anything fancy with the allocation of this memory to the
 323          * zones, now is the time to do it.
 324          */
 325         zone_size[0] = max_low - min;
 326 #ifdef CONFIG_HIGHMEM
 327         zone_size[ZONE_HIGHMEM] = max_high - max_low;
 328 #endif
 329
 330         /*
 331          * For each bank in this node, calculate the size of the holes.
 332          *  holes = node_size - sum(bank_sizes_in_node)
 333          */
 334         memcpy(zhole_size, zone_size, sizeof(zhole_size));
 335         for_each_nodebank(i, mi, node) {
 336                 int idx = 0;
 337 #ifdef CONFIG_HIGHMEM
 338                 if (mi->bank[i].highmem)
 339                         idx = ZONE_HIGHMEM;
 340 #endif
 341                 zhole_size[idx] -= bank_pfn_size(&mi->bank[i]);
 342         }
 343
 344         /*
 345          * Adjust the sizes according to any special requirements for
 346          * this machine type.
 347          */
 348         arch_adjust_zones(node, zone_size, zhole_size);
 349
 350         free_area_init_node(node, zone_size, min, zhole_size);
 351 }
 352
 353 #ifndef CONFIG_SPARSEMEM
 354 int pfn_valid(unsigned long pfn)
 355 {
 356         struct meminfo *mi = &meminfo;
 357         unsigned int left = 0, right = mi->nr_banks;
 358
 359         do {
 360                 unsigned int mid = (right + left) / 2;
 361                 struct membank *bank = &mi->bank[mid];
 362
 363                 if (pfn < bank_pfn_start(bank))
 364                         right = mid;
 365                 else if (pfn >= bank_pfn_end(bank))
 366                         left = mid + 1;
 367                 else
 368                         return 1;
 369         } while (left < right);
 370         return 0;
 371 }
 372 EXPORT_SYMBOL(pfn_valid);
 373 #endif
 374
 375 static int __init meminfo_cmp(const void *_a, const void *_b)
 376 {
 377         const struct membank *a = _a, *b = _b;
 378         long cmp = bank_pfn_start(a) - bank_pfn_start(b);
 379         return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
 380 }
 381
 382 void __init bootmem_init(void)
 383 {
 384         struct meminfo *mi = &meminfo;
 385         unsigned long min, max_low, max_high;
 386         int node, initrd_node;
 387
 388         sort(&mi->bank, mi->nr_banks, sizeof(mi->bank[0]), meminfo_cmp, NULL);
 389
 390         /*
 391          * Locate which node contains the ramdisk image, if any.
 392          */
 393         initrd_node = check_initrd(mi);
 394
 395         max_low = max_high = 0;
 396
 397         /*
 398          * Run through each node initialising the bootmem allocator.
 399          */
 400         for_each_node(node) {
 401                 unsigned long node_low, node_high;
 402
 403                 find_node_limits(node, mi, &min, &node_low, &node_high);
 404
 405                 if (node_low > max_low)
 406                         max_low = node_low;
 407                 if (node_high > max_high)
 408                         max_high = node_high;
 409
 410                 /*
 411                  * If there is no memory in this node, ignore it.
 412                  * (We can't have nodes which have no lowmem)
 413                  */
 414                 if (node_low == 0)
 415                         continue;
 416
 417                 bootmem_init_node(node, mi, min, node_low);
 418
 419                 /*
 420                  * Reserve any special node zero regions.
 421                  */
 422                 if (node == 0)
 423                         reserve_node_zero(NODE_DATA(node));
 424
 425                 /*
 426                  * If the initrd is in this node, reserve its memory.
 427                  */
 428                 if (node == initrd_node)
 429                         bootmem_reserve_initrd(node);
 430         }
 431
 432         /*
 433          * sparse_init() needs the bootmem allocator up and running.
 434          */
 435         sparse_init();
 436
 437         /*
 438          * Now free memory in each node - free_area_init_node needs
 439          * the sparse mem_map arrays initialized by sparse_init()
 440          * for memmap_init_zone(), otherwise all PFNs are invalid.
 441          */
 442         for_each_node(node)
 443                 bootmem_free_node(node, mi);
 444
 445         high_memory = __va((max_low << PAGE_SHIFT) - 1) + 1;
 446
 447         /*
 448          * This doesn't seem to be used by the Linux memory manager any
 449          * more, but is used by ll_rw_block.  If we can get rid of it, we
 450          * also get rid of some of the stuff above as well.
 451          *
 452          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 453          * the system, not the maximum PFN.
 454          */
 455         max_low_pfn = max_low - PHYS_PFN_OFFSET;
 456         max_pfn = max_high - PHYS_PFN_OFFSET;
 457 }
 458
 459 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
 460 {
 461         unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
 462
 463         for (; pfn < end; pfn++) {
 464                 struct page *page = pfn_to_page(pfn);
 465                 ClearPageReserved(page);
 466                 init_page_count(page);
 467                 __free_page(page);
 468                 pages++;
 469         }
 470
 471         if (size && s)
 472                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 473
 474         return pages;
 475 }
 476
 477 static inline void
 478 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 479 {
 480         struct page *start_pg, *end_pg;
 481         unsigned long pg, pgend;
 482
 483         /*
 484          * Convert start_pfn/end_pfn to a struct page pointer.
 485          */
 486         start_pg = pfn_to_page(start_pfn - 1) + 1;
 487         end_pg = pfn_to_page(end_pfn);
 488
 489         /*
 490          * Convert to physical addresses, and
 491          * round start upwards and end downwards.
 492          */
 493         pg = PAGE_ALIGN(__pa(start_pg));
 494         pgend = __pa(end_pg) & PAGE_MASK;
 495
 496         /*
 497          * If there are free pages between these,
 498          * free the section of the memmap array.
 499          */
 500         if (pg < pgend)
 501                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 502 }
 503
 504 /*
 505  * The mem_map array can get very big.  Free the unused area of the memory map.
 506  */
 507 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 508 {
 509         unsigned long bank_start, prev_bank_end = 0;
 510         unsigned int i;
 511
 512         /*
 513          * [FIXME] This relies on each bank being in address order.  This
 514          * may not be the case, especially if the user has provided the
 515          * information on the command line.
 516          */
 517         for_each_nodebank(i, mi, node) {
 518                 struct membank *bank = &mi->bank[i];
 519
 520                 bank_start = bank_pfn_start(bank);
 521                 if (bank_start < prev_bank_end) {
 522                         printk(KERN_ERR "MEM: unordered memory banks.  "
 523                                 "Not freeing memmap.\n");
 524                         break;
 525                 }
 526
 527                 /*
 528                  * If we had a previous bank, and there is a space
 529                  * between the current bank and the previous, free it.
 530                  */
 531                 if (prev_bank_end && prev_bank_end != bank_start)
 532                         free_memmap(node, prev_bank_end, bank_start);
 533
 534                 prev_bank_end = bank_pfn_end(bank);
 535         }
 536 }
 537
 538 /*
 539  * mem_init() marks the free areas in the mem_map and tells us how much
 540  * memory is free.  This is done after various parts of the system have
 541  * claimed their memory after the kernel image.
 542  */
 543 void __init mem_init(void)
 544 {
 545         unsigned int codesize, datasize, initsize;
 546         int i, node;
 547
 548 #ifndef CONFIG_DISCONTIGMEM
 549         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 550 #endif
 551
 552         /* this will put all unused low memory onto the freelists */
 553         for_each_online_node(node) {
 554                 pg_data_t *pgdat = NODE_DATA(node);
 555
 556                 free_unused_memmap_node(node, &meminfo);
 557
 558                 if (pgdat->node_spanned_pages != 0)
 559                         totalram_pages += free_all_bootmem_node(pgdat);
 560         }
 561
 562 #ifdef CONFIG_SA1111
 563         /* now that our DMA memory is actually so designated, we can free it */
 564         totalram_pages += free_area(PHYS_PFN_OFFSET,
 565                                     __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
 566 #endif
 567
 568 #ifdef CONFIG_HIGHMEM
 569         /* set highmem page free */
 570         for_each_online_node(node) {
 571                 for_each_nodebank (i, &meminfo, node) {
 572                         unsigned long start = bank_pfn_start(&meminfo.bank[i]);
 573                         unsigned long end = bank_pfn_end(&meminfo.bank[i]);
 574                         if (start >= max_low_pfn + PHYS_PFN_OFFSET)
 575                                 totalhigh_pages += free_area(start, end, NULL);
 576                 }
 577         }
 578         totalram_pages += totalhigh_pages;
 579 #endif
 580
 581         /*
 582          * Since our memory may not be contiguous, calculate the
 583          * real number of pages we have in this system
 584          */
 585         printk(KERN_INFO "Memory:");
 586         num_physpages = 0;
 587         for (i = 0; i < meminfo.nr_banks; i++) {
 588                 num_physpages += bank_pfn_size(&meminfo.bank[i]);
 589                 printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
 590         }
 591         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 592
 593         codesize = _etext - _text;
 594         datasize = _end - _data;
 595         initsize = __init_end - __init_begin;
 596
 597         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 598                 "%dK data, %dK init, %luK highmem)\n",
 599                 nr_free_pages() << (PAGE_SHIFT-10), codesize >> 10,
 600                 datasize >> 10, initsize >> 10,
 601                 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 602
 603         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 604                 extern int sysctl_overcommit_memory;
 605                 /*
 606                  * On a machine this small we won't get
 607                  * anywhere without overcommit, so turn
 608                  * it on by default.
 609                  */
 610                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 611         }
 612 }
 613
 614 void free_initmem(void)
 615 {
 616 #ifdef CONFIG_HAVE_TCM
 617         extern char *__tcm_start, *__tcm_end;
 618
 619         totalram_pages += free_area(__phys_to_pfn(__pa(__tcm_start)),
 620                                     __phys_to_pfn(__pa(__tcm_end)),
 621                                     "TCM link");
 622 #endif
 623
 624         if (!machine_is_integrator() && !machine_is_cintegrator())
 625                 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
 626                                             __phys_to_pfn(__pa(__init_end)),
 627                                             "init");
 628 }
 629
 630 #ifdef CONFIG_BLK_DEV_INITRD
 631
 632 static int keep_initrd;
 633
 634 void free_initrd_mem(unsigned long start, unsigned long end)
 635 {
 636         if (!keep_initrd)
 637                 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
 638                                             __phys_to_pfn(__pa(end)),
 639                                             "initrd");
 640 }
 641
 642 static int __init keepinitrd_setup(char *__unused)
 643 {
 644         keep_initrd = 1;
 645         return 1;
 646 }
 647
 648 __setup("keepinitrd", keepinitrd_setup);
 649 #endif