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 #include <linux/gfp.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 #include <asm/fixmap.h>
  27
  28 #include <asm/mach/arch.h>
  29 #include <asm/mach/map.h>
  30
  31 #include "mm.h"
  32
  33 static unsigned long phys_initrd_start __initdata = 0;
  34 static unsigned long phys_initrd_size __initdata = 0;
  35
  36 static int __init early_initrd(char *p)
  37 {
  38         unsigned long start, size;
  39         char *endp;
  40
  41         start = memparse(p, &endp);
  42         if (*endp == ',') {
  43                 size = memparse(endp + 1, NULL);
  44
  45                 phys_initrd_start = start;
  46                 phys_initrd_size = size;
  47         }
  48         return 0;
  49 }
  50 early_param("initrd", early_initrd);
  51
  52 static int __init parse_tag_initrd(const struct tag *tag)
  53 {
  54         printk(KERN_WARNING "ATAG_INITRD is deprecated; "
  55                 "please update your bootloader.\n");
  56         phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
  57         phys_initrd_size = tag->u.initrd.size;
  58         return 0;
  59 }
  60
  61 __tagtable(ATAG_INITRD, parse_tag_initrd);
  62
  63 static int __init parse_tag_initrd2(const struct tag *tag)
  64 {
  65         phys_initrd_start = tag->u.initrd.start;
  66         phys_initrd_size = tag->u.initrd.size;
  67         return 0;
  68 }
  69
  70 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
  71
  72 /*
  73  * This keeps memory configuration data used by a couple memory
  74  * initialization functions, as well as show_mem() for the skipping
  75  * of holes in the memory map.  It is populated by arm_add_memory().
  76  */
  77 struct meminfo meminfo;
  78
  79 void show_mem(void)
  80 {
  81         int free = 0, total = 0, reserved = 0;
  82         int shared = 0, cached = 0, slab = 0, i;
  83         struct meminfo * mi = &meminfo;
  84
  85         printk("Mem-info:\n");
  86         show_free_areas();
  87
  88         for_each_bank (i, mi) {
  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 = pfn_to_page(pfn1);
  97                 end  = pfn_to_page(pfn2 - 1) + 1;
  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         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_limits(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_bank (i, mi) {
 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(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_bank(i, mi) {
 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 = -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 = -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 = 0;
 211                 }
 212         }
 213
 214         if (initrd == -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;
 223 }
 224
 225 static void __init arm_bootmem_init(struct meminfo *mi,
 226         unsigned long start_pfn, unsigned long end_pfn)
 227 {
 228         unsigned long boot_pfn;
 229         unsigned int boot_pages;
 230         pg_data_t *pgdat;
 231         int i;
 232
 233         /*
 234          * Allocate the bootmem bitmap page.
 235          */
 236         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 237         boot_pfn = find_bootmap_pfn(mi, boot_pages);
 238
 239         /*
 240          * Initialise the bootmem allocator, handing the
 241          * memory banks over to bootmem.
 242          */
 243         node_set_online(0);
 244         pgdat = NODE_DATA(0);
 245         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 246
 247         for_each_bank(i, mi) {
 248                 struct membank *bank = &mi->bank[i];
 249                 if (!bank->highmem)
 250                         free_bootmem(bank_phys_start(bank), bank_phys_size(bank));
 251         }
 252
 253         /*
 254          * Reserve the bootmem bitmap.
 255          */
 256         reserve_bootmem(boot_pfn << PAGE_SHIFT,
 257                         boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
 258 }
 259
 260 static void __init bootmem_reserve_initrd(void)
 261 {
 262 #ifdef CONFIG_BLK_DEV_INITRD
 263         int res;
 264
 265         res = reserve_bootmem(phys_initrd_start,
 266                               phys_initrd_size, BOOTMEM_EXCLUSIVE);
 267
 268         if (res == 0) {
 269                 initrd_start = __phys_to_virt(phys_initrd_start);
 270                 initrd_end = initrd_start + phys_initrd_size;
 271         } else {
 272                 printk(KERN_ERR
 273                         "INITRD: 0x%08lx+0x%08lx overlaps in-use "
 274                         "memory region - disabling initrd\n",
 275                         phys_initrd_start, phys_initrd_size);
 276         }
 277 #endif
 278 }
 279
 280 static void __init arm_bootmem_free(struct meminfo *mi)
 281 {
 282         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 283         unsigned long min, max_low, max_high;
 284         int i;
 285
 286         find_limits(mi, &min, &max_low, &max_high);
 287
 288         /*
 289          * initialise the zones.
 290          */
 291         memset(zone_size, 0, sizeof(zone_size));
 292
 293         /*
 294          * The memory size has already been determined.  If we need
 295          * to do anything fancy with the allocation of this memory
 296          * to the zones, now is the time to do it.
 297          */
 298         zone_size[0] = max_low - min;
 299 #ifdef CONFIG_HIGHMEM
 300         zone_size[ZONE_HIGHMEM] = max_high - max_low;
 301 #endif
 302
 303         /*
 304          * Calculate the size of the holes.
 305          *  holes = node_size - sum(bank_sizes)
 306          */
 307         memcpy(zhole_size, zone_size, sizeof(zhole_size));
 308         for_each_bank(i, mi) {
 309                 int idx = 0;
 310 #ifdef CONFIG_HIGHMEM
 311                 if (mi->bank[i].highmem)
 312                         idx = ZONE_HIGHMEM;
 313 #endif
 314                 zhole_size[idx] -= bank_pfn_size(&mi->bank[i]);
 315         }
 316
 317         /*
 318          * Adjust the sizes according to any special requirements for
 319          * this machine type.
 320          */
 321         arch_adjust_zones(0, zone_size, zhole_size);
 322
 323         free_area_init_node(0, zone_size, min, zhole_size);
 324 }
 325
 326 #ifndef CONFIG_SPARSEMEM
 327 int pfn_valid(unsigned long pfn)
 328 {
 329         struct meminfo *mi = &meminfo;
 330         unsigned int left = 0, right = mi->nr_banks;
 331
 332         do {
 333                 unsigned int mid = (right + left) / 2;
 334                 struct membank *bank = &mi->bank[mid];
 335
 336                 if (pfn < bank_pfn_start(bank))
 337                         right = mid;
 338                 else if (pfn >= bank_pfn_end(bank))
 339                         left = mid + 1;
 340                 else
 341                         return 1;
 342         } while (left < right);
 343         return 0;
 344 }
 345 EXPORT_SYMBOL(pfn_valid);
 346
 347 static void arm_memory_present(struct meminfo *mi)
 348 {
 349 }
 350 #else
 351 static void arm_memory_present(struct meminfo *mi)
 352 {
 353         int i;
 354         for_each_bank(i, mi) {
 355                 struct membank *bank = &mi->bank[i];
 356                 memory_present(0, bank_pfn_start(bank), bank_pfn_end(bank));
 357         }
 358 }
 359 #endif
 360
 361 void __init bootmem_init(void)
 362 {
 363         struct meminfo *mi = &meminfo;
 364         unsigned long min, max_low, max_high;
 365         int initrd;
 366
 367         /*
 368          * Locate the ramdisk image, if any.
 369          */
 370         initrd = check_initrd(mi);
 371
 372         max_low = max_high = 0;
 373
 374         find_limits(mi, &min, &max_low, &max_high);
 375
 376         arm_bootmem_init(mi, min, max_low);
 377
 378         /*
 379          * Reserve any special regions.
 380          */
 381         reserve_special_regions();
 382
 383         /*
 384          * If the initrd is present, reserve its memory.
 385          */
 386         if (initrd == 0)
 387                 bootmem_reserve_initrd();
 388
 389         /*
 390          * Sparsemem tries to allocate bootmem in memory_present(),
 391          * so must be done after the fixed reservations
 392          */
 393         arm_memory_present(mi);
 394
 395         /*
 396          * sparse_init() needs the bootmem allocator up and running.
 397          */
 398         sparse_init();
 399
 400         /*
 401          * Now free the memory - free_area_init_node needs
 402          * the sparse mem_map arrays initialized by sparse_init()
 403          * for memmap_init_zone(), otherwise all PFNs are invalid.
 404          */
 405         arm_bootmem_free(mi);
 406
 407         high_memory = __va((max_low << PAGE_SHIFT) - 1) + 1;
 408
 409         /*
 410          * This doesn't seem to be used by the Linux memory manager any
 411          * more, but is used by ll_rw_block.  If we can get rid of it, we
 412          * also get rid of some of the stuff above as well.
 413          *
 414          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 415          * the system, not the maximum PFN.
 416          */
 417         max_low_pfn = max_low - PHYS_PFN_OFFSET;
 418         max_pfn = max_high - PHYS_PFN_OFFSET;
 419 }
 420
 421 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
 422 {
 423         unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
 424
 425         for (; pfn < end; pfn++) {
 426                 struct page *page = pfn_to_page(pfn);
 427                 ClearPageReserved(page);
 428                 init_page_count(page);
 429                 __free_page(page);
 430                 pages++;
 431         }
 432
 433         if (size && s)
 434                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 435
 436         return pages;
 437 }
 438
 439 static inline void
 440 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 441 {
 442         struct page *start_pg, *end_pg;
 443         unsigned long pg, pgend;
 444
 445         /*
 446          * Convert start_pfn/end_pfn to a struct page pointer.
 447          */
 448         start_pg = pfn_to_page(start_pfn - 1) + 1;
 449         end_pg = pfn_to_page(end_pfn);
 450
 451         /*
 452          * Convert to physical addresses, and
 453          * round start upwards and end downwards.
 454          */
 455         pg = PAGE_ALIGN(__pa(start_pg));
 456         pgend = __pa(end_pg) & PAGE_MASK;
 457
 458         /*
 459          * If there are free pages between these,
 460          * free the section of the memmap array.
 461          */
 462         if (pg < pgend)
 463                 free_bootmem(pg, pgend - pg);
 464 }
 465
 466 /*
 467  * The mem_map array can get very big.  Free the unused area of the memory map.
 468  */
 469 static void __init free_unused_memmap(struct meminfo *mi)
 470 {
 471         unsigned long bank_start, prev_bank_end = 0;
 472         unsigned int i;
 473
 474         /*
 475          * [FIXME] This relies on each bank being in address order.  This
 476          * may not be the case, especially if the user has provided the
 477          * information on the command line.
 478          */
 479         for_each_bank(i, mi) {
 480                 struct membank *bank = &mi->bank[i];
 481
 482                 bank_start = bank_pfn_start(bank);
 483                 if (bank_start < prev_bank_end) {
 484                         printk(KERN_ERR "MEM: unordered memory banks.  "
 485                                 "Not freeing memmap.\n");
 486                         break;
 487                 }
 488
 489                 /*
 490                  * If we had a previous bank, and there is a space
 491                  * between the current bank and the previous, free it.
 492                  */
 493                 if (prev_bank_end && prev_bank_end != bank_start)
 494                         free_memmap(prev_bank_end, bank_start);
 495
 496                 prev_bank_end = bank_pfn_end(bank);
 497         }
 498 }
 499
 500 /*
 501  * mem_init() marks the free areas in the mem_map and tells us how much
 502  * memory is free.  This is done after various parts of the system have
 503  * claimed their memory after the kernel image.
 504  */
 505 void __init mem_init(void)
 506 {
 507         unsigned long reserved_pages, free_pages;
 508         int i;
 509
 510         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 511
 512         /* this will put all unused low memory onto the freelists */
 513         free_unused_memmap(&meminfo);
 514
 515         totalram_pages += free_all_bootmem();
 516
 517 #ifdef CONFIG_SA1111
 518         /* now that our DMA memory is actually so designated, we can free it */
 519         totalram_pages += free_area(PHYS_PFN_OFFSET,
 520                                     __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
 521 #endif
 522
 523 #ifdef CONFIG_HIGHMEM
 524         /* set highmem page free */
 525         for_each_bank (i, &meminfo) {
 526                 unsigned long start = bank_pfn_start(&meminfo.bank[i]);
 527                 unsigned long end = bank_pfn_end(&meminfo.bank[i]);
 528                 if (start >= max_low_pfn + PHYS_PFN_OFFSET)
 529                         totalhigh_pages += free_area(start, end, NULL);
 530         }
 531         totalram_pages += totalhigh_pages;
 532 #endif
 533
 534         reserved_pages = free_pages = 0;
 535
 536         for_each_bank(i, &meminfo) {
 537                 struct membank *bank = &meminfo.bank[i];
 538                 unsigned int pfn1, pfn2;
 539                 struct page *page, *end;
 540
 541                 pfn1 = bank_pfn_start(bank);
 542                 pfn2 = bank_pfn_end(bank);
 543
 544                 page = pfn_to_page(pfn1);
 545                 end  = pfn_to_page(pfn2 - 1) + 1;
 546
 547                 do {
 548                         if (PageReserved(page))
 549                                 reserved_pages++;
 550                         else if (!page_count(page))
 551                                 free_pages++;
 552                         page++;
 553                 } while (page < end);
 554         }
 555
 556         /*
 557          * Since our memory may not be contiguous, calculate the
 558          * real number of pages we have in this system
 559          */
 560         printk(KERN_INFO "Memory:");
 561         num_physpages = 0;
 562         for (i = 0; i < meminfo.nr_banks; i++) {
 563                 num_physpages += bank_pfn_size(&meminfo.bank[i]);
 564                 printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
 565         }
 566         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 567
 568         printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n",
 569                 nr_free_pages() << (PAGE_SHIFT-10),
 570                 free_pages << (PAGE_SHIFT-10),
 571                 reserved_pages << (PAGE_SHIFT-10),
 572                 totalhigh_pages << (PAGE_SHIFT-10));
 573
 574 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 575 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 576 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 577
 578         printk(KERN_NOTICE "Virtual kernel memory layout:\n"
 579                         "    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 580                         "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 581 #ifdef CONFIG_MMU
 582                         "    DMA     : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 583 #endif
 584                         "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 585                         "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 586 #ifdef CONFIG_HIGHMEM
 587                         "    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 588 #endif
 589                         "    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 590                         "      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
 591                         "      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
 592                         "      .data : 0x%p" " - 0x%p" "   (%4d kB)\n",
 593
 594                         MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
 595                                 (PAGE_SIZE)),
 596                         MLK(FIXADDR_START, FIXADDR_TOP),
 597 #ifdef CONFIG_MMU
 598                         MLM(CONSISTENT_BASE, CONSISTENT_END),
 599 #endif
 600                         MLM(VMALLOC_START, VMALLOC_END),
 601                         MLM(PAGE_OFFSET, (unsigned long)high_memory),
 602 #ifdef CONFIG_HIGHMEM
 603                         MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
 604                                 (PAGE_SIZE)),
 605 #endif
 606                         MLM(MODULES_VADDR, MODULES_END),
 607
 608                         MLK_ROUNDUP(__init_begin, __init_end),
 609                         MLK_ROUNDUP(_text, _etext),
 610                         MLK_ROUNDUP(_data, _edata));
 611
 612 #undef MLK
 613 #undef MLM
 614 #undef MLK_ROUNDUP
 615
 616         /*
 617          * Check boundaries twice: Some fundamental inconsistencies can
 618          * be detected at build time already.
 619          */
 620 #ifdef CONFIG_MMU
 621         BUILD_BUG_ON(VMALLOC_END                        > CONSISTENT_BASE);
 622         BUG_ON(VMALLOC_END                              > CONSISTENT_BASE);
 623
 624         BUILD_BUG_ON(TASK_SIZE                          > MODULES_VADDR);
 625         BUG_ON(TASK_SIZE                                > MODULES_VADDR);
 626 #endif
 627
 628 #ifdef CONFIG_HIGHMEM
 629         BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
 630         BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE      > PAGE_OFFSET);
 631 #endif
 632
 633         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 634                 extern int sysctl_overcommit_memory;
 635                 /*
 636                  * On a machine this small we won't get
 637                  * anywhere without overcommit, so turn
 638                  * it on by default.
 639                  */
 640                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 641         }
 642 }
 643
 644 void free_initmem(void)
 645 {
 646 #ifdef CONFIG_HAVE_TCM
 647         extern char __tcm_start, __tcm_end;
 648
 649         totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
 650                                     __phys_to_pfn(__pa(&__tcm_end)),
 651                                     "TCM link");
 652 #endif
 653
 654         if (!machine_is_integrator() && !machine_is_cintegrator())
 655                 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
 656                                             __phys_to_pfn(__pa(__init_end)),
 657                                             "init");
 658 }
 659
 660 #ifdef CONFIG_BLK_DEV_INITRD
 661
 662 static int keep_initrd;
 663
 664 void free_initrd_mem(unsigned long start, unsigned long end)
 665 {
 666         if (!keep_initrd)
 667                 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
 668                                             __phys_to_pfn(__pa(end)),
 669                                             "initrd");
 670 }
 671
 672 static int __init keepinitrd_setup(char *__unused)
 673 {
 674         keep_initrd = 1;
 675         return 1;
 676 }
 677
 678 __setup("keepinitrd", keepinitrd_setup);
 679 #endif