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/export.h>
  17 #include <linux/nodemask.h>
  18 #include <linux/initrd.h>
  19 #include <linux/of_fdt.h>
  20 #include <linux/of_reserved_mem.h>
  21 #include <linux/highmem.h>
  22 #include <linux/gfp.h>
  23 #include <linux/memblock.h>
  24 #include <linux/dma-contiguous.h>
  25 #include <linux/sizes.h>
  26
  27 #include <asm/mach-types.h>
  28 #include <asm/memblock.h>
  29 #include <asm/prom.h>
  30 #include <asm/sections.h>
  31 #include <asm/setup.h>
  32 #include <asm/tlb.h>
  33 #include <asm/fixmap.h>
  34
  35 #include <asm/mach/arch.h>
  36 #include <asm/mach/map.h>
  37
  38 #include "mm.h"
  39
  40 static phys_addr_t phys_initrd_start __initdata = 0;
  41 static unsigned long phys_initrd_size __initdata = 0;
  42
  43 static int __init early_initrd(char *p)
  44 {
  45         phys_addr_t start;
  46         unsigned long size;
  47         char *endp;
  48
  49         start = memparse(p, &endp);
  50         if (*endp == ',') {
  51                 size = memparse(endp + 1, NULL);
  52
  53                 phys_initrd_start = start;
  54                 phys_initrd_size = size;
  55         }
  56         return 0;
  57 }
  58 early_param("initrd", early_initrd);
  59
  60 static int __init parse_tag_initrd(const struct tag *tag)
  61 {
  62         printk(KERN_WARNING "ATAG_INITRD is deprecated; "
  63                 "please update your bootloader.\n");
  64         phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
  65         phys_initrd_size = tag->u.initrd.size;
  66         return 0;
  67 }
  68
  69 __tagtable(ATAG_INITRD, parse_tag_initrd);
  70
  71 static int __init parse_tag_initrd2(const struct tag *tag)
  72 {
  73         phys_initrd_start = tag->u.initrd.start;
  74         phys_initrd_size = tag->u.initrd.size;
  75         return 0;
  76 }
  77
  78 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
  79
  80 #ifdef CONFIG_OF_FLATTREE
  81 void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
  82 {
  83         phys_initrd_start = start;
  84         phys_initrd_size = end - start;
  85 }
  86 #endif /* CONFIG_OF_FLATTREE */
  87
  88 /*
  89  * This keeps memory configuration data used by a couple memory
  90  * initialization functions, as well as show_mem() for the skipping
  91  * of holes in the memory map.  It is populated by arm_add_memory().
  92  */
  93 struct meminfo meminfo;
  94
  95 void show_mem(unsigned int filter)
  96 {
  97         int free = 0, total = 0, reserved = 0;
  98         int shared = 0, cached = 0, slab = 0, i;
  99         struct meminfo * mi = &meminfo;
 100
 101         printk("Mem-info:\n");
 102         show_free_areas(filter);
 103
 104         if (filter & SHOW_MEM_FILTER_PAGE_COUNT)
 105                 return;
 106
 107         for_each_bank (i, mi) {
 108                 struct membank *bank = &mi->bank[i];
 109                 unsigned int pfn1, pfn2;
 110                 struct page *page, *end;
 111
 112                 pfn1 = bank_pfn_start(bank);
 113                 pfn2 = bank_pfn_end(bank);
 114
 115                 page = pfn_to_page(pfn1);
 116                 end  = pfn_to_page(pfn2 - 1) + 1;
 117
 118                 do {
 119                         total++;
 120                         if (PageReserved(page))
 121                                 reserved++;
 122                         else if (PageSwapCache(page))
 123                                 cached++;
 124                         else if (PageSlab(page))
 125                                 slab++;
 126                         else if (!page_count(page))
 127                                 free++;
 128                         else
 129                                 shared += page_count(page) - 1;
 130                         page++;
 131                 } while (page < end);
 132         }
 133
 134         printk("%d pages of RAM\n", total);
 135         printk("%d free pages\n", free);
 136         printk("%d reserved pages\n", reserved);
 137         printk("%d slab pages\n", slab);
 138         printk("%d pages shared\n", shared);
 139         printk("%d pages swap cached\n", cached);
 140 }
 141
 142 static void __init find_limits(unsigned long *min, unsigned long *max_low,
 143                                unsigned long *max_high)
 144 {
 145         struct meminfo *mi = &meminfo;
 146         int i;
 147
 148         /* This assumes the meminfo array is properly sorted */
 149         *min = bank_pfn_start(&mi->bank[0]);
 150         for_each_bank (i, mi)
 151                 if (mi->bank[i].highmem)
 152                                 break;
 153         *max_low = bank_pfn_end(&mi->bank[i - 1]);
 154         *max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
 155 }
 156
 157 static void __init arm_bootmem_init(unsigned long start_pfn,
 158         unsigned long end_pfn)
 159 {
 160         struct memblock_region *reg;
 161         unsigned int boot_pages;
 162         phys_addr_t bitmap;
 163         pg_data_t *pgdat;
 164
 165         /*
 166          * Allocate the bootmem bitmap page.  This must be in a region
 167          * of memory which has already been mapped.
 168          */
 169         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 170         bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
 171                                 __pfn_to_phys(end_pfn));
 172
 173         /*
 174          * Initialise the bootmem allocator, handing the
 175          * memory banks over to bootmem.
 176          */
 177         node_set_online(0);
 178         pgdat = NODE_DATA(0);
 179         init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
 180
 181         /* Free the lowmem regions from memblock into bootmem. */
 182         for_each_memblock(memory, reg) {
 183                 unsigned long start = memblock_region_memory_base_pfn(reg);
 184                 unsigned long end = memblock_region_memory_end_pfn(reg);
 185
 186                 if (end >= end_pfn)
 187                         end = end_pfn;
 188                 if (start >= end)
 189                         break;
 190
 191                 free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
 192         }
 193
 194         /* Reserve the lowmem memblock reserved regions in bootmem. */
 195         for_each_memblock(reserved, reg) {
 196                 unsigned long start = memblock_region_reserved_base_pfn(reg);
 197                 unsigned long end = memblock_region_reserved_end_pfn(reg);
 198
 199                 if (end >= end_pfn)
 200                         end = end_pfn;
 201                 if (start >= end)
 202                         break;
 203
 204                 reserve_bootmem(__pfn_to_phys(start),
 205                                 (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
 206         }
 207 }
 208
 209 #ifdef CONFIG_ZONE_DMA
 210
 211 phys_addr_t arm_dma_zone_size __read_mostly;
 212 EXPORT_SYMBOL(arm_dma_zone_size);
 213
 214 /*
 215  * The DMA mask corresponding to the maximum bus address allocatable
 216  * using GFP_DMA.  The default here places no restriction on DMA
 217  * allocations.  This must be the smallest DMA mask in the system,
 218  * so a successful GFP_DMA allocation will always satisfy this.
 219  */
 220 phys_addr_t arm_dma_limit;
 221
 222 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
 223         unsigned long dma_size)
 224 {
 225         if (size[0] <= dma_size)
 226                 return;
 227
 228         size[ZONE_NORMAL] = size[0] - dma_size;
 229         size[ZONE_DMA] = dma_size;
 230         hole[ZONE_NORMAL] = hole[0];
 231         hole[ZONE_DMA] = 0;
 232 }
 233 #endif
 234
 235 void __init setup_dma_zone(const struct machine_desc *mdesc)
 236 {
 237 #ifdef CONFIG_ZONE_DMA
 238         if (mdesc->dma_zone_size) {
 239                 arm_dma_zone_size = mdesc->dma_zone_size;
 240                 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
 241         } else
 242                 arm_dma_limit = 0xffffffff;
 243 #endif
 244 }
 245
 246 static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
 247         unsigned long max_high)
 248 {
 249         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 250         struct memblock_region *reg;
 251
 252         /*
 253          * initialise the zones.
 254          */
 255         memset(zone_size, 0, sizeof(zone_size));
 256
 257         /*
 258          * The memory size has already been determined.  If we need
 259          * to do anything fancy with the allocation of this memory
 260          * to the zones, now is the time to do it.
 261          */
 262         zone_size[0] = max_low - min;
 263 #ifdef CONFIG_HIGHMEM
 264         zone_size[ZONE_HIGHMEM] = max_high - max_low;
 265 #endif
 266
 267         /*
 268          * Calculate the size of the holes.
 269          *  holes = node_size - sum(bank_sizes)
 270          */
 271         memcpy(zhole_size, zone_size, sizeof(zhole_size));
 272         for_each_memblock(memory, reg) {
 273                 unsigned long start = memblock_region_memory_base_pfn(reg);
 274                 unsigned long end = memblock_region_memory_end_pfn(reg);
 275
 276                 if (start < max_low) {
 277                         unsigned long low_end = min(end, max_low);
 278                         zhole_size[0] -= low_end - start;
 279                 }
 280 #ifdef CONFIG_HIGHMEM
 281                 if (end > max_low) {
 282                         unsigned long high_start = max(start, max_low);
 283                         zhole_size[ZONE_HIGHMEM] -= end - high_start;
 284                 }
 285 #endif
 286         }
 287
 288 #ifdef CONFIG_ZONE_DMA
 289         /*
 290          * Adjust the sizes according to any special requirements for
 291          * this machine type.
 292          */
 293         if (arm_dma_zone_size)
 294                 arm_adjust_dma_zone(zone_size, zhole_size,
 295                         arm_dma_zone_size >> PAGE_SHIFT);
 296 #endif
 297
 298         free_area_init_node(0, zone_size, min, zhole_size);
 299 }
 300
 301 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 302 int pfn_valid(unsigned long pfn)
 303 {
 304         return memblock_is_memory(__pfn_to_phys(pfn));
 305 }
 306 EXPORT_SYMBOL(pfn_valid);
 307 #endif
 308
 309 #ifndef CONFIG_SPARSEMEM
 310 static void __init arm_memory_present(void)
 311 {
 312 }
 313 #else
 314 static void __init arm_memory_present(void)
 315 {
 316         struct memblock_region *reg;
 317
 318         for_each_memblock(memory, reg)
 319                 memory_present(0, memblock_region_memory_base_pfn(reg),
 320                                memblock_region_memory_end_pfn(reg));
 321 }
 322 #endif
 323
 324 static bool arm_memblock_steal_permitted = true;
 325
 326 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
 327 {
 328         phys_addr_t phys;
 329
 330         BUG_ON(!arm_memblock_steal_permitted);
 331
 332         phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
 333         memblock_free(phys, size);
 334         memblock_remove(phys, size);
 335
 336         return phys;
 337 }
 338
 339 void __init arm_memblock_init(struct meminfo *mi,
 340         const struct machine_desc *mdesc)
 341 {
 342         int i;
 343
 344         for (i = 0; i < mi->nr_banks; i++)
 345                 memblock_add(mi->bank[i].start, mi->bank[i].size);
 346
 347         /* Register the kernel text, kernel data and initrd with memblock. */
 348 #ifdef CONFIG_XIP_KERNEL
 349         memblock_reserve(__pa(_sdata), _end - _sdata);
 350 #else
 351         memblock_reserve(__pa(_stext), _end - _stext);
 352 #endif
 353 #ifdef CONFIG_BLK_DEV_INITRD
 354         if (phys_initrd_size &&
 355             !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
 356                 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
 357                        (u64)phys_initrd_start, phys_initrd_size);
 358                 phys_initrd_start = phys_initrd_size = 0;
 359         }
 360         if (phys_initrd_size &&
 361             memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
 362                 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
 363                        (u64)phys_initrd_start, phys_initrd_size);
 364                 phys_initrd_start = phys_initrd_size = 0;
 365         }
 366         if (phys_initrd_size) {
 367                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 368
 369                 /* Now convert initrd to virtual addresses */
 370                 initrd_start = __phys_to_virt(phys_initrd_start);
 371                 initrd_end = initrd_start + phys_initrd_size;
 372         }
 373 #endif
 374
 375         arm_mm_memblock_reserve();
 376         arm_dt_memblock_reserve();
 377
 378         /* reserve any platform specific memblock areas */
 379         if (mdesc->reserve)
 380                 mdesc->reserve();
 381
 382         early_init_dt_scan_reserved_mem();
 383
 384         /*
 385          * reserve memory for DMA contigouos allocations,
 386          * must come from DMA area inside low memory
 387          */
 388         dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
 389
 390         arm_memblock_steal_permitted = false;
 391         memblock_allow_resize();
 392         memblock_dump_all();
 393 }
 394
 395 void __init bootmem_init(void)
 396 {
 397         unsigned long min, max_low, max_high;
 398
 399         max_low = max_high = 0;
 400
 401         find_limits(&min, &max_low, &max_high);
 402
 403         arm_bootmem_init(min, max_low);
 404
 405         /*
 406          * Sparsemem tries to allocate bootmem in memory_present(),
 407          * so must be done after the fixed reservations
 408          */
 409         arm_memory_present();
 410
 411         /*
 412          * sparse_init() needs the bootmem allocator up and running.
 413          */
 414         sparse_init();
 415
 416         /*
 417          * Now free the memory - free_area_init_node needs
 418          * the sparse mem_map arrays initialized by sparse_init()
 419          * for memmap_init_zone(), otherwise all PFNs are invalid.
 420          */
 421         arm_bootmem_free(min, max_low, max_high);
 422
 423         /*
 424          * This doesn't seem to be used by the Linux memory manager any
 425          * more, but is used by ll_rw_block.  If we can get rid of it, we
 426          * also get rid of some of the stuff above as well.
 427          *
 428          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 429          * the system, not the maximum PFN.
 430          */
 431         max_low_pfn = max_low - PHYS_PFN_OFFSET;
 432         max_pfn = max_high - PHYS_PFN_OFFSET;
 433 }
 434
 435 /*
 436  * Poison init memory with an undefined instruction (ARM) or a branch to an
 437  * undefined instruction (Thumb).
 438  */
 439 static inline void poison_init_mem(void *s, size_t count)
 440 {
 441         u32 *p = (u32 *)s;
 442         for (; count != 0; count -= 4)
 443                 *p++ = 0xe7fddef0;
 444 }
 445
 446 static inline void
 447 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 448 {
 449         struct page *start_pg, *end_pg;
 450         phys_addr_t pg, pgend;
 451
 452         /*
 453          * Convert start_pfn/end_pfn to a struct page pointer.
 454          */
 455         start_pg = pfn_to_page(start_pfn - 1) + 1;
 456         end_pg = pfn_to_page(end_pfn - 1) + 1;
 457
 458         /*
 459          * Convert to physical addresses, and
 460          * round start upwards and end downwards.
 461          */
 462         pg = PAGE_ALIGN(__pa(start_pg));
 463         pgend = __pa(end_pg) & PAGE_MASK;
 464
 465         /*
 466          * If there are free pages between these,
 467          * free the section of the memmap array.
 468          */
 469         if (pg < pgend)
 470                 free_bootmem(pg, pgend - pg);
 471 }
 472
 473 /*
 474  * The mem_map array can get very big.  Free the unused area of the memory map.
 475  */
 476 static void __init free_unused_memmap(struct meminfo *mi)
 477 {
 478         unsigned long bank_start, prev_bank_end = 0;
 479         unsigned int i;
 480
 481         /*
 482          * This relies on each bank being in address order.
 483          * The banks are sorted previously in bootmem_init().
 484          */
 485         for_each_bank(i, mi) {
 486                 struct membank *bank = &mi->bank[i];
 487
 488                 bank_start = bank_pfn_start(bank);
 489
 490 #ifdef CONFIG_SPARSEMEM
 491                 /*
 492                  * Take care not to free memmap entries that don't exist
 493                  * due to SPARSEMEM sections which aren't present.
 494                  */
 495                 bank_start = min(bank_start,
 496                                  ALIGN(prev_bank_end, PAGES_PER_SECTION));
 497 #else
 498                 /*
 499                  * Align down here since the VM subsystem insists that the
 500                  * memmap entries are valid from the bank start aligned to
 501                  * MAX_ORDER_NR_PAGES.
 502                  */
 503                 bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
 504 #endif
 505                 /*
 506                  * If we had a previous bank, and there is a space
 507                  * between the current bank and the previous, free it.
 508                  */
 509                 if (prev_bank_end && prev_bank_end < bank_start)
 510                         free_memmap(prev_bank_end, bank_start);
 511
 512                 /*
 513                  * Align up here since the VM subsystem insists that the
 514                  * memmap entries are valid from the bank end aligned to
 515                  * MAX_ORDER_NR_PAGES.
 516                  */
 517                 prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
 518         }
 519
 520 #ifdef CONFIG_SPARSEMEM
 521         if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
 522                 free_memmap(prev_bank_end,
 523                             ALIGN(prev_bank_end, PAGES_PER_SECTION));
 524 #endif
 525 }
 526
 527 #ifdef CONFIG_HIGHMEM
 528 static inline void free_area_high(unsigned long pfn, unsigned long end)
 529 {
 530         for (; pfn < end; pfn++)
 531                 free_highmem_page(pfn_to_page(pfn));
 532 }
 533 #endif
 534
 535 static void __init free_highpages(void)
 536 {
 537 #ifdef CONFIG_HIGHMEM
 538         unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
 539         struct memblock_region *mem, *res;
 540
 541         /* set highmem page free */
 542         for_each_memblock(memory, mem) {
 543                 unsigned long start = memblock_region_memory_base_pfn(mem);
 544                 unsigned long end = memblock_region_memory_end_pfn(mem);
 545
 546                 /* Ignore complete lowmem entries */
 547                 if (end <= max_low)
 548                         continue;
 549
 550                 /* Truncate partial highmem entries */
 551                 if (start < max_low)
 552                         start = max_low;
 553
 554                 /* Find and exclude any reserved regions */
 555                 for_each_memblock(reserved, res) {
 556                         unsigned long res_start, res_end;
 557
 558                         res_start = memblock_region_reserved_base_pfn(res);
 559                         res_end = memblock_region_reserved_end_pfn(res);
 560
 561                         if (res_end < start)
 562                                 continue;
 563                         if (res_start < start)
 564                                 res_start = start;
 565                         if (res_start > end)
 566                                 res_start = end;
 567                         if (res_end > end)
 568                                 res_end = end;
 569                         if (res_start != start)
 570                                 free_area_high(start, res_start);
 571                         start = res_end;
 572                         if (start == end)
 573                                 break;
 574                 }
 575
 576                 /* And now free anything which remains */
 577                 if (start < end)
 578                         free_area_high(start, end);
 579         }
 580 #endif
 581 }
 582
 583 /*
 584  * mem_init() marks the free areas in the mem_map and tells us how much
 585  * memory is free.  This is done after various parts of the system have
 586  * claimed their memory after the kernel image.
 587  */
 588 void __init mem_init(void)
 589 {
 590 #ifdef CONFIG_HAVE_TCM
 591         /* These pointers are filled in on TCM detection */
 592         extern u32 dtcm_end;
 593         extern u32 itcm_end;
 594 #endif
 595
 596         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 597
 598         /* this will put all unused low memory onto the freelists */
 599         free_unused_memmap(&meminfo);
 600         free_all_bootmem();
 601
 602 #ifdef CONFIG_SA1111
 603         /* now that our DMA memory is actually so designated, we can free it */
 604         free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
 605 #endif
 606
 607         free_highpages();
 608
 609         mem_init_print_info(NULL);
 610
 611 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 612 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 613 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 614
 615         printk(KERN_NOTICE "Virtual kernel memory layout:\n"
 616                         "    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 617 #ifdef CONFIG_HAVE_TCM
 618                         "    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 619                         "    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 620 #endif
 621                         "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 622                         "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 623                         "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 624 #ifdef CONFIG_HIGHMEM
 625                         "    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 626 #endif
 627 #ifdef CONFIG_MODULES
 628                         "    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 629 #endif
 630                         "      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
 631                         "      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
 632                         "      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
 633                         "       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
 634
 635                         MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
 636                                 (PAGE_SIZE)),
 637 #ifdef CONFIG_HAVE_TCM
 638                         MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
 639                         MLK(ITCM_OFFSET, (unsigned long) itcm_end),
 640 #endif
 641                         MLK(FIXADDR_START, FIXADDR_TOP),
 642                         MLM(VMALLOC_START, VMALLOC_END),
 643                         MLM(PAGE_OFFSET, (unsigned long)high_memory),
 644 #ifdef CONFIG_HIGHMEM
 645                         MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
 646                                 (PAGE_SIZE)),
 647 #endif
 648 #ifdef CONFIG_MODULES
 649                         MLM(MODULES_VADDR, MODULES_END),
 650 #endif
 651
 652                         MLK_ROUNDUP(_text, _etext),
 653                         MLK_ROUNDUP(__init_begin, __init_end),
 654                         MLK_ROUNDUP(_sdata, _edata),
 655                         MLK_ROUNDUP(__bss_start, __bss_stop));
 656
 657 #undef MLK
 658 #undef MLM
 659 #undef MLK_ROUNDUP
 660
 661         /*
 662          * Check boundaries twice: Some fundamental inconsistencies can
 663          * be detected at build time already.
 664          */
 665 #ifdef CONFIG_MMU
 666         BUILD_BUG_ON(TASK_SIZE                          > MODULES_VADDR);
 667         BUG_ON(TASK_SIZE                                > MODULES_VADDR);
 668 #endif
 669
 670 #ifdef CONFIG_HIGHMEM
 671         BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
 672         BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE      > PAGE_OFFSET);
 673 #endif
 674
 675         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 676                 extern int sysctl_overcommit_memory;
 677                 /*
 678                  * On a machine this small we won't get
 679                  * anywhere without overcommit, so turn
 680                  * it on by default.
 681                  */
 682                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 683         }
 684 }
 685
 686 void free_initmem(void)
 687 {
 688 #ifdef CONFIG_HAVE_TCM
 689         extern char __tcm_start, __tcm_end;
 690
 691         poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
 692         free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
 693 #endif
 694
 695         poison_init_mem(__init_begin, __init_end - __init_begin);
 696         if (!machine_is_integrator() && !machine_is_cintegrator())
 697                 free_initmem_default(-1);
 698 }
 699
 700 #ifdef CONFIG_BLK_DEV_INITRD
 701
 702 static int keep_initrd;
 703
 704 void free_initrd_mem(unsigned long start, unsigned long end)
 705 {
 706         if (!keep_initrd) {
 707                 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
 708                 free_reserved_area((void *)start, (void *)end, -1, "initrd");
 709         }
 710 }
 711
 712 static int __init keepinitrd_setup(char *__unused)
 713 {
 714         keep_initrd = 1;
 715         return 1;
 716 }
 717
 718 __setup("keepinitrd", keepinitrd_setup);
 719 #endif