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