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 = n->node_mem_map - 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
 211 bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
 212 {
 213         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 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         }
 264
 265         /*
 266          * Reserve the bootmem bitmap for this node.
 267          */
 268         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 269                              boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
 270
 271         /*
 272          * Reserve any special node zero regions.
 273          */
 274         if (node == 0)
 275                 reserve_node_zero(pgdat);
 276
 277 #ifdef CONFIG_BLK_DEV_INITRD
 278         /*
 279          * If the initrd is in this node, reserve its memory.
 280          */
 281         if (node == initrd_node) {
 282                 int res = reserve_bootmem_node(pgdat, phys_initrd_start,
 283                                      phys_initrd_size, BOOTMEM_EXCLUSIVE);
 284
 285                 if (res == 0) {
 286                         initrd_start = __phys_to_virt(phys_initrd_start);
 287                         initrd_end = initrd_start + phys_initrd_size;
 288                 } else {
 289                         printk(KERN_ERR
 290                                 "INITRD: 0x%08lx+0x%08lx overlaps in-use "
 291                                 "memory region - disabling initrd\n",
 292                                 phys_initrd_start, phys_initrd_size);
 293                 }
 294         }
 295 #endif
 296
 297         /*
 298          * initialise the zones within this node.
 299          */
 300         memset(zone_size, 0, sizeof(zone_size));
 301         memset(zhole_size, 0, sizeof(zhole_size));
 302
 303         /*
 304          * The size of this node has already been determined.  If we need
 305          * to do anything fancy with the allocation of this memory to the
 306          * zones, now is the time to do it.
 307          */
 308         zone_size[0] = end_pfn - start_pfn;
 309
 310         /*
 311          * For each bank in this node, calculate the size of the holes.
 312          *  holes = node_size - sum(bank_sizes_in_node)
 313          */
 314         zhole_size[0] = zone_size[0];
 315         for_each_nodebank(i, mi, node)
 316                 zhole_size[0] -= bank_pfn_size(&mi->bank[i]);
 317
 318         /*
 319          * Adjust the sizes according to any special requirements for
 320          * this machine type.
 321          */
 322         arch_adjust_zones(node, zone_size, zhole_size);
 323
 324         free_area_init_node(node, zone_size, start_pfn, zhole_size);
 325
 326         return end_pfn;
 327 }
 328
 329 void __init bootmem_init(struct meminfo *mi)
 330 {
 331         unsigned long memend_pfn = 0;
 332         int node, initrd_node;
 333
 334         memcpy(&meminfo, mi, sizeof(meminfo));
 335
 336         /*
 337          * Locate which node contains the ramdisk image, if any.
 338          */
 339         initrd_node = check_initrd(mi);
 340
 341         /*
 342          * Run through each node initialising the bootmem allocator.
 343          */
 344         for_each_node(node) {
 345                 unsigned long end_pfn;
 346
 347                 end_pfn = bootmem_init_node(node, initrd_node, mi);
 348
 349                 /*
 350                  * Remember the highest memory PFN.
 351                  */
 352                 if (end_pfn > memend_pfn)
 353                         memend_pfn = end_pfn;
 354         }
 355
 356         high_memory = __va(memend_pfn << PAGE_SHIFT);
 357
 358         /*
 359          * This doesn't seem to be used by the Linux memory manager any
 360          * more, but is used by ll_rw_block.  If we can get rid of it, we
 361          * also get rid of some of the stuff above as well.
 362          *
 363          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 364          * the system, not the maximum PFN.
 365          */
 366         max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 367 }
 368
 369 static inline void free_area(unsigned long addr, unsigned long end, char *s)
 370 {
 371         unsigned int size = (end - addr) >> 10;
 372
 373         for (; addr < end; addr += PAGE_SIZE) {
 374                 struct page *page = virt_to_page(addr);
 375                 ClearPageReserved(page);
 376                 init_page_count(page);
 377                 free_page(addr);
 378                 totalram_pages++;
 379         }
 380
 381         if (size && s)
 382                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 383 }
 384
 385 static inline void
 386 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 387 {
 388         struct page *start_pg, *end_pg;
 389         unsigned long pg, pgend;
 390
 391         /*
 392          * Convert start_pfn/end_pfn to a struct page pointer.
 393          */
 394         start_pg = pfn_to_page(start_pfn);
 395         end_pg = pfn_to_page(end_pfn);
 396
 397         /*
 398          * Convert to physical addresses, and
 399          * round start upwards and end downwards.
 400          */
 401         pg = PAGE_ALIGN(__pa(start_pg));
 402         pgend = __pa(end_pg) & PAGE_MASK;
 403
 404         /*
 405          * If there are free pages between these,
 406          * free the section of the memmap array.
 407          */
 408         if (pg < pgend)
 409                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 410 }
 411
 412 /*
 413  * The mem_map array can get very big.  Free the unused area of the memory map.
 414  */
 415 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 416 {
 417         unsigned long bank_start, prev_bank_end = 0;
 418         unsigned int i;
 419
 420         /*
 421          * [FIXME] This relies on each bank being in address order.  This
 422          * may not be the case, especially if the user has provided the
 423          * information on the command line.
 424          */
 425         for_each_nodebank(i, mi, node) {
 426                 struct membank *bank = &mi->bank[i];
 427
 428                 bank_start = bank_pfn_start(bank);
 429                 if (bank_start < prev_bank_end) {
 430                         printk(KERN_ERR "MEM: unordered memory banks.  "
 431                                 "Not freeing memmap.\n");
 432                         break;
 433                 }
 434
 435                 /*
 436                  * If we had a previous bank, and there is a space
 437                  * between the current bank and the previous, free it.
 438                  */
 439                 if (prev_bank_end && prev_bank_end != bank_start)
 440                         free_memmap(node, prev_bank_end, bank_start);
 441
 442                 prev_bank_end = bank_pfn_end(bank);
 443         }
 444 }
 445
 446 /*
 447  * mem_init() marks the free areas in the mem_map and tells us how much
 448  * memory is free.  This is done after various parts of the system have
 449  * claimed their memory after the kernel image.
 450  */
 451 void __init mem_init(void)
 452 {
 453         unsigned int codepages, datapages, initpages;
 454         int i, node;
 455
 456         codepages = &_etext - &_text;
 457         datapages = &_end - &__data_start;
 458         initpages = &__init_end - &__init_begin;
 459
 460 #ifndef CONFIG_DISCONTIGMEM
 461         max_mapnr   = virt_to_page(high_memory) - mem_map;
 462 #endif
 463
 464         /* this will put all unused low memory onto the freelists */
 465         for_each_online_node(node) {
 466                 pg_data_t *pgdat = NODE_DATA(node);
 467
 468                 free_unused_memmap_node(node, &meminfo);
 469
 470                 if (pgdat->node_spanned_pages != 0)
 471                         totalram_pages += free_all_bootmem_node(pgdat);
 472         }
 473
 474 #ifdef CONFIG_SA1111
 475         /* now that our DMA memory is actually so designated, we can free it */
 476         free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
 477 #endif
 478
 479         /*
 480          * Since our memory may not be contiguous, calculate the
 481          * real number of pages we have in this system
 482          */
 483         printk(KERN_INFO "Memory:");
 484
 485         num_physpages = 0;
 486         for (i = 0; i < meminfo.nr_banks; i++) {
 487                 num_physpages += bank_pfn_size(&meminfo.bank[i]);
 488                 printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
 489         }
 490
 491         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 492         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 493                 "%dK data, %dK init)\n",
 494                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 495                 codepages >> 10, datapages >> 10, initpages >> 10);
 496
 497         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 498                 extern int sysctl_overcommit_memory;
 499                 /*
 500                  * On a machine this small we won't get
 501                  * anywhere without overcommit, so turn
 502                  * it on by default.
 503                  */
 504                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 505         }
 506 }
 507
 508 void free_initmem(void)
 509 {
 510         if (!machine_is_integrator() && !machine_is_cintegrator()) {
 511                 free_area((unsigned long)(&__init_begin),
 512                           (unsigned long)(&__init_end),
 513                           "init");
 514         }
 515 }
 516
 517 #ifdef CONFIG_BLK_DEV_INITRD
 518
 519 static int keep_initrd;
 520
 521 void free_initrd_mem(unsigned long start, unsigned long end)
 522 {
 523         if (!keep_initrd)
 524                 free_area(start, end, "initrd");
 525 }
 526
 527 static int __init keepinitrd_setup(char *__unused)
 528 {
 529         keep_initrd = 1;
 530         return 1;
 531 }
 532
 533 __setup("keepinitrd", keepinitrd_setup);
 534 #endif