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