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