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