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 unsigned long 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 unsigned long start, size; 45 char *endp; 46 47 start = memparse(p, &endp); 48 if (*endp == ',') { 49 size = memparse(endp + 1, NULL); 50 51 phys_initrd_start = start; 52 phys_initrd_size = size; 53 } 54 return 0; 55 } 56 early_param("initrd", early_initrd); 57 58 static int __init parse_tag_initrd(const struct tag *tag) 59 { 60 printk(KERN_WARNING "ATAG_INITRD is deprecated; " 61 "please update your bootloader.\n"); 62 phys_initrd_start = __virt_to_phys(tag->u.initrd.start); 63 phys_initrd_size = tag->u.initrd.size; 64 return 0; 65 } 66 67 __tagtable(ATAG_INITRD, parse_tag_initrd); 68 69 static int __init parse_tag_initrd2(const struct tag *tag) 70 { 71 phys_initrd_start = tag->u.initrd.start; 72 phys_initrd_size = tag->u.initrd.size; 73 return 0; 74 } 75 76 __tagtable(ATAG_INITRD2, parse_tag_initrd2); 77 78 #ifdef CONFIG_OF_FLATTREE 79 void __init early_init_dt_setup_initrd_arch(unsigned long start, unsigned long end) 80 { 81 phys_initrd_start = start; 82 phys_initrd_size = end - start; 83 } 84 #endif /* CONFIG_OF_FLATTREE */ 85 86 /* 87 * This keeps memory configuration data used by a couple memory 88 * initialization functions, as well as show_mem() for the skipping 89 * of holes in the memory map. It is populated by arm_add_memory(). 90 */ 91 struct meminfo meminfo; 92 93 void show_mem(unsigned int filter) 94 { 95 int free = 0, total = 0, reserved = 0; 96 int shared = 0, cached = 0, slab = 0, i; 97 struct meminfo * mi = &meminfo; 98 99 printk("Mem-info:\n"); 100 show_free_areas(filter); 101 102 if (filter & SHOW_MEM_FILTER_PAGE_COUNT) 103 return; 104 105 for_each_bank (i, mi) { 106 struct membank *bank = &mi->bank[i]; 107 unsigned int pfn1, pfn2; 108 struct page *page, *end; 109 110 pfn1 = bank_pfn_start(bank); 111 pfn2 = bank_pfn_end(bank); 112 113 page = pfn_to_page(pfn1); 114 end = pfn_to_page(pfn2 - 1) + 1; 115 116 do { 117 total++; 118 if (PageReserved(page)) 119 reserved++; 120 else if (PageSwapCache(page)) 121 cached++; 122 else if (PageSlab(page)) 123 slab++; 124 else if (!page_count(page)) 125 free++; 126 else 127 shared += page_count(page) - 1; 128 page++; 129 } while (page < end); 130 } 131 132 printk("%d pages of RAM\n", total); 133 printk("%d free pages\n", free); 134 printk("%d reserved pages\n", reserved); 135 printk("%d slab pages\n", slab); 136 printk("%d pages shared\n", shared); 137 printk("%d pages swap cached\n", cached); 138 } 139 140 static void __init find_limits(unsigned long *min, unsigned long *max_low, 141 unsigned long *max_high) 142 { 143 struct meminfo *mi = &meminfo; 144 int i; 145 146 /* This assumes the meminfo array is properly sorted */ 147 *min = bank_pfn_start(&mi->bank[0]); 148 for_each_bank (i, mi) 149 if (mi->bank[i].highmem) 150 break; 151 *max_low = bank_pfn_end(&mi->bank[i - 1]); 152 *max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]); 153 } 154 155 static void __init arm_bootmem_init(unsigned long start_pfn, 156 unsigned long end_pfn) 157 { 158 struct memblock_region *reg; 159 unsigned int boot_pages; 160 phys_addr_t bitmap; 161 pg_data_t *pgdat; 162 163 /* 164 * Allocate the bootmem bitmap page. This must be in a region 165 * of memory which has already been mapped. 166 */ 167 boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn); 168 bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES, 169 __pfn_to_phys(end_pfn)); 170 171 /* 172 * Initialise the bootmem allocator, handing the 173 * memory banks over to bootmem. 174 */ 175 node_set_online(0); 176 pgdat = NODE_DATA(0); 177 init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn); 178 179 /* Free the lowmem regions from memblock into bootmem. */ 180 for_each_memblock(memory, reg) { 181 unsigned long start = memblock_region_memory_base_pfn(reg); 182 unsigned long end = memblock_region_memory_end_pfn(reg); 183 184 if (end >= end_pfn) 185 end = end_pfn; 186 if (start >= end) 187 break; 188 189 free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT); 190 } 191 192 /* Reserve the lowmem memblock reserved regions in bootmem. */ 193 for_each_memblock(reserved, reg) { 194 unsigned long start = memblock_region_reserved_base_pfn(reg); 195 unsigned long end = memblock_region_reserved_end_pfn(reg); 196 197 if (end >= end_pfn) 198 end = end_pfn; 199 if (start >= end) 200 break; 201 202 reserve_bootmem(__pfn_to_phys(start), 203 (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT); 204 } 205 } 206 207 #ifdef CONFIG_ZONE_DMA 208 209 unsigned long arm_dma_zone_size __read_mostly; 210 EXPORT_SYMBOL(arm_dma_zone_size); 211 212 /* 213 * The DMA mask corresponding to the maximum bus address allocatable 214 * using GFP_DMA. The default here places no restriction on DMA 215 * allocations. This must be the smallest DMA mask in the system, 216 * so a successful GFP_DMA allocation will always satisfy this. 217 */ 218 phys_addr_t arm_dma_limit; 219 220 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole, 221 unsigned long dma_size) 222 { 223 if (size[0] <= dma_size) 224 return; 225 226 size[ZONE_NORMAL] = size[0] - dma_size; 227 size[ZONE_DMA] = dma_size; 228 hole[ZONE_NORMAL] = hole[0]; 229 hole[ZONE_DMA] = 0; 230 } 231 #endif 232 233 void __init setup_dma_zone(struct machine_desc *mdesc) 234 { 235 #ifdef CONFIG_ZONE_DMA 236 if (mdesc->dma_zone_size) { 237 arm_dma_zone_size = mdesc->dma_zone_size; 238 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1; 239 } else 240 arm_dma_limit = 0xffffffff; 241 #endif 242 } 243 244 static void __init arm_bootmem_free(unsigned long min, unsigned long max_low, 245 unsigned long max_high) 246 { 247 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 248 struct memblock_region *reg; 249 250 /* 251 * initialise the zones. 252 */ 253 memset(zone_size, 0, sizeof(zone_size)); 254 255 /* 256 * The memory size has already been determined. If we need 257 * to do anything fancy with the allocation of this memory 258 * to the zones, now is the time to do it. 259 */ 260 zone_size[0] = max_low - min; 261 #ifdef CONFIG_HIGHMEM 262 zone_size[ZONE_HIGHMEM] = max_high - max_low; 263 #endif 264 265 /* 266 * Calculate the size of the holes. 267 * holes = node_size - sum(bank_sizes) 268 */ 269 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 270 for_each_memblock(memory, reg) { 271 unsigned long start = memblock_region_memory_base_pfn(reg); 272 unsigned long end = memblock_region_memory_end_pfn(reg); 273 274 if (start < max_low) { 275 unsigned long low_end = min(end, max_low); 276 zhole_size[0] -= low_end - start; 277 } 278 #ifdef CONFIG_HIGHMEM 279 if (end > max_low) { 280 unsigned long high_start = max(start, max_low); 281 zhole_size[ZONE_HIGHMEM] -= end - high_start; 282 } 283 #endif 284 } 285 286 #ifdef CONFIG_ZONE_DMA 287 /* 288 * Adjust the sizes according to any special requirements for 289 * this machine type. 290 */ 291 if (arm_dma_zone_size) 292 arm_adjust_dma_zone(zone_size, zhole_size, 293 arm_dma_zone_size >> PAGE_SHIFT); 294 #endif 295 296 free_area_init_node(0, zone_size, min, zhole_size); 297 } 298 299 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 300 int pfn_valid(unsigned long pfn) 301 { 302 return memblock_is_memory(__pfn_to_phys(pfn)); 303 } 304 EXPORT_SYMBOL(pfn_valid); 305 #endif 306 307 #ifndef CONFIG_SPARSEMEM 308 static void __init arm_memory_present(void) 309 { 310 } 311 #else 312 static void __init arm_memory_present(void) 313 { 314 struct memblock_region *reg; 315 316 for_each_memblock(memory, reg) 317 memory_present(0, memblock_region_memory_base_pfn(reg), 318 memblock_region_memory_end_pfn(reg)); 319 } 320 #endif 321 322 static bool arm_memblock_steal_permitted = true; 323 324 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align) 325 { 326 phys_addr_t phys; 327 328 BUG_ON(!arm_memblock_steal_permitted); 329 330 phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE); 331 memblock_free(phys, size); 332 memblock_remove(phys, size); 333 334 return phys; 335 } 336 337 void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc) 338 { 339 int i; 340 341 for (i = 0; i < mi->nr_banks; i++) 342 memblock_add(mi->bank[i].start, mi->bank[i].size); 343 344 /* Register the kernel text, kernel data and initrd with memblock. */ 345 #ifdef CONFIG_XIP_KERNEL 346 memblock_reserve(__pa(_sdata), _end - _sdata); 347 #else 348 memblock_reserve(__pa(_stext), _end - _stext); 349 #endif 350 #ifdef CONFIG_BLK_DEV_INITRD 351 if (phys_initrd_size && 352 !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) { 353 pr_err("INITRD: 0x%08lx+0x%08lx is not a memory region - disabling initrd\n", 354 phys_initrd_start, phys_initrd_size); 355 phys_initrd_start = phys_initrd_size = 0; 356 } 357 if (phys_initrd_size && 358 memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) { 359 pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n", 360 phys_initrd_start, phys_initrd_size); 361 phys_initrd_start = phys_initrd_size = 0; 362 } 363 if (phys_initrd_size) { 364 memblock_reserve(phys_initrd_start, phys_initrd_size); 365 366 /* Now convert initrd to virtual addresses */ 367 initrd_start = __phys_to_virt(phys_initrd_start); 368 initrd_end = initrd_start + phys_initrd_size; 369 } 370 #endif 371 372 arm_mm_memblock_reserve(); 373 arm_dt_memblock_reserve(); 374 375 /* reserve any platform specific memblock areas */ 376 if (mdesc->reserve) 377 mdesc->reserve(); 378 379 /* 380 * reserve memory for DMA contigouos allocations, 381 * must come from DMA area inside low memory 382 */ 383 dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit)); 384 385 arm_memblock_steal_permitted = false; 386 memblock_allow_resize(); 387 memblock_dump_all(); 388 } 389 390 void __init bootmem_init(void) 391 { 392 unsigned long min, max_low, max_high; 393 394 max_low = max_high = 0; 395 396 find_limits(&min, &max_low, &max_high); 397 398 arm_bootmem_init(min, max_low); 399 400 /* 401 * Sparsemem tries to allocate bootmem in memory_present(), 402 * so must be done after the fixed reservations 403 */ 404 arm_memory_present(); 405 406 /* 407 * sparse_init() needs the bootmem allocator up and running. 408 */ 409 sparse_init(); 410 411 /* 412 * Now free the memory - free_area_init_node needs 413 * the sparse mem_map arrays initialized by sparse_init() 414 * for memmap_init_zone(), otherwise all PFNs are invalid. 415 */ 416 arm_bootmem_free(min, max_low, max_high); 417 418 /* 419 * This doesn't seem to be used by the Linux memory manager any 420 * more, but is used by ll_rw_block. If we can get rid of it, we 421 * also get rid of some of the stuff above as well. 422 * 423 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in 424 * the system, not the maximum PFN. 425 */ 426 max_low_pfn = max_low - PHYS_PFN_OFFSET; 427 max_pfn = max_high - PHYS_PFN_OFFSET; 428 } 429 430 /* 431 * Poison init memory with an undefined instruction (ARM) or a branch to an 432 * undefined instruction (Thumb). 433 */ 434 static inline void poison_init_mem(void *s, size_t count) 435 { 436 u32 *p = (u32 *)s; 437 for (; count != 0; count -= 4) 438 *p++ = 0xe7fddef0; 439 } 440 441 static inline void 442 free_memmap(unsigned long start_pfn, unsigned long end_pfn) 443 { 444 struct page *start_pg, *end_pg; 445 unsigned long pg, pgend; 446 447 /* 448 * Convert start_pfn/end_pfn to a struct page pointer. 449 */ 450 start_pg = pfn_to_page(start_pfn - 1) + 1; 451 end_pg = pfn_to_page(end_pfn - 1) + 1; 452 453 /* 454 * Convert to physical addresses, and 455 * round start upwards and end downwards. 456 */ 457 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg)); 458 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK; 459 460 /* 461 * If there are free pages between these, 462 * free the section of the memmap array. 463 */ 464 if (pg < pgend) 465 free_bootmem(pg, pgend - pg); 466 } 467 468 /* 469 * The mem_map array can get very big. Free the unused area of the memory map. 470 */ 471 static void __init free_unused_memmap(struct meminfo *mi) 472 { 473 unsigned long bank_start, prev_bank_end = 0; 474 unsigned int i; 475 476 /* 477 * This relies on each bank being in address order. 478 * The banks are sorted previously in bootmem_init(). 479 */ 480 for_each_bank(i, mi) { 481 struct membank *bank = &mi->bank[i]; 482 483 bank_start = bank_pfn_start(bank); 484 485 #ifdef CONFIG_SPARSEMEM 486 /* 487 * Take care not to free memmap entries that don't exist 488 * due to SPARSEMEM sections which aren't present. 489 */ 490 bank_start = min(bank_start, 491 ALIGN(prev_bank_end, PAGES_PER_SECTION)); 492 #else 493 /* 494 * Align down here since the VM subsystem insists that the 495 * memmap entries are valid from the bank start aligned to 496 * MAX_ORDER_NR_PAGES. 497 */ 498 bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES); 499 #endif 500 /* 501 * If we had a previous bank, and there is a space 502 * between the current bank and the previous, free it. 503 */ 504 if (prev_bank_end && prev_bank_end < bank_start) 505 free_memmap(prev_bank_end, bank_start); 506 507 /* 508 * Align up here since the VM subsystem insists that the 509 * memmap entries are valid from the bank end aligned to 510 * MAX_ORDER_NR_PAGES. 511 */ 512 prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES); 513 } 514 515 #ifdef CONFIG_SPARSEMEM 516 if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION)) 517 free_memmap(prev_bank_end, 518 ALIGN(prev_bank_end, PAGES_PER_SECTION)); 519 #endif 520 } 521 522 #ifdef CONFIG_HIGHMEM 523 static inline void free_area_high(unsigned long pfn, unsigned long end) 524 { 525 for (; pfn < end; pfn++) 526 free_highmem_page(pfn_to_page(pfn)); 527 } 528 #endif 529 530 static void __init free_highpages(void) 531 { 532 #ifdef CONFIG_HIGHMEM 533 unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET; 534 struct memblock_region *mem, *res; 535 536 /* set highmem page free */ 537 for_each_memblock(memory, mem) { 538 unsigned long start = memblock_region_memory_base_pfn(mem); 539 unsigned long end = memblock_region_memory_end_pfn(mem); 540 541 /* Ignore complete lowmem entries */ 542 if (end <= max_low) 543 continue; 544 545 /* Truncate partial highmem entries */ 546 if (start < max_low) 547 start = max_low; 548 549 /* Find and exclude any reserved regions */ 550 for_each_memblock(reserved, res) { 551 unsigned long res_start, res_end; 552 553 res_start = memblock_region_reserved_base_pfn(res); 554 res_end = memblock_region_reserved_end_pfn(res); 555 556 if (res_end < start) 557 continue; 558 if (res_start < start) 559 res_start = start; 560 if (res_start > end) 561 res_start = end; 562 if (res_end > end) 563 res_end = end; 564 if (res_start != start) 565 free_area_high(start, res_start); 566 start = res_end; 567 if (start == end) 568 break; 569 } 570 571 /* And now free anything which remains */ 572 if (start < end) 573 free_area_high(start, end); 574 } 575 #endif 576 } 577 578 /* 579 * mem_init() marks the free areas in the mem_map and tells us how much 580 * memory is free. This is done after various parts of the system have 581 * claimed their memory after the kernel image. 582 */ 583 void __init mem_init(void) 584 { 585 unsigned long reserved_pages, free_pages; 586 struct memblock_region *reg; 587 int i; 588 #ifdef CONFIG_HAVE_TCM 589 /* These pointers are filled in on TCM detection */ 590 extern u32 dtcm_end; 591 extern u32 itcm_end; 592 #endif 593 594 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map; 595 596 /* this will put all unused low memory onto the freelists */ 597 free_unused_memmap(&meminfo); 598 599 totalram_pages += free_all_bootmem(); 600 601 #ifdef CONFIG_SA1111 602 /* now that our DMA memory is actually so designated, we can free it */ 603 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, 0, NULL); 604 #endif 605 606 free_highpages(); 607 608 reserved_pages = free_pages = 0; 609 610 for_each_bank(i, &meminfo) { 611 struct membank *bank = &meminfo.bank[i]; 612 unsigned int pfn1, pfn2; 613 struct page *page, *end; 614 615 pfn1 = bank_pfn_start(bank); 616 pfn2 = bank_pfn_end(bank); 617 618 page = pfn_to_page(pfn1); 619 end = pfn_to_page(pfn2 - 1) + 1; 620 621 do { 622 if (PageReserved(page)) 623 reserved_pages++; 624 else if (!page_count(page)) 625 free_pages++; 626 page++; 627 } while (page < end); 628 } 629 630 /* 631 * Since our memory may not be contiguous, calculate the 632 * real number of pages we have in this system 633 */ 634 printk(KERN_INFO "Memory:"); 635 num_physpages = 0; 636 for_each_memblock(memory, reg) { 637 unsigned long pages = memblock_region_memory_end_pfn(reg) - 638 memblock_region_memory_base_pfn(reg); 639 num_physpages += pages; 640 printk(" %ldMB", pages >> (20 - PAGE_SHIFT)); 641 } 642 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT)); 643 644 printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n", 645 nr_free_pages() << (PAGE_SHIFT-10), 646 free_pages << (PAGE_SHIFT-10), 647 reserved_pages << (PAGE_SHIFT-10), 648 totalhigh_pages << (PAGE_SHIFT-10)); 649 650 #define MLK(b, t) b, t, ((t) - (b)) >> 10 651 #define MLM(b, t) b, t, ((t) - (b)) >> 20 652 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 653 654 printk(KERN_NOTICE "Virtual kernel memory layout:\n" 655 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n" 656 #ifdef CONFIG_HAVE_TCM 657 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n" 658 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n" 659 #endif 660 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" 661 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" 662 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" 663 #ifdef CONFIG_HIGHMEM 664 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n" 665 #endif 666 #ifdef CONFIG_MODULES 667 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n" 668 #endif 669 " .text : 0x%p" " - 0x%p" " (%4d kB)\n" 670 " .init : 0x%p" " - 0x%p" " (%4d kB)\n" 671 " .data : 0x%p" " - 0x%p" " (%4d kB)\n" 672 " .bss : 0x%p" " - 0x%p" " (%4d kB)\n", 673 674 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) + 675 (PAGE_SIZE)), 676 #ifdef CONFIG_HAVE_TCM 677 MLK(DTCM_OFFSET, (unsigned long) dtcm_end), 678 MLK(ITCM_OFFSET, (unsigned long) itcm_end), 679 #endif 680 MLK(FIXADDR_START, FIXADDR_TOP), 681 MLM(VMALLOC_START, VMALLOC_END), 682 MLM(PAGE_OFFSET, (unsigned long)high_memory), 683 #ifdef CONFIG_HIGHMEM 684 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) * 685 (PAGE_SIZE)), 686 #endif 687 #ifdef CONFIG_MODULES 688 MLM(MODULES_VADDR, MODULES_END), 689 #endif 690 691 MLK_ROUNDUP(_text, _etext), 692 MLK_ROUNDUP(__init_begin, __init_end), 693 MLK_ROUNDUP(_sdata, _edata), 694 MLK_ROUNDUP(__bss_start, __bss_stop)); 695 696 #undef MLK 697 #undef MLM 698 #undef MLK_ROUNDUP 699 700 /* 701 * Check boundaries twice: Some fundamental inconsistencies can 702 * be detected at build time already. 703 */ 704 #ifdef CONFIG_MMU 705 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); 706 BUG_ON(TASK_SIZE > MODULES_VADDR); 707 #endif 708 709 #ifdef CONFIG_HIGHMEM 710 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); 711 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); 712 #endif 713 714 if (PAGE_SIZE >= 16384 && num_physpages <= 128) { 715 extern int sysctl_overcommit_memory; 716 /* 717 * On a machine this small we won't get 718 * anywhere without overcommit, so turn 719 * it on by default. 720 */ 721 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 722 } 723 } 724 725 void free_initmem(void) 726 { 727 #ifdef CONFIG_HAVE_TCM 728 extern char __tcm_start, __tcm_end; 729 730 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start); 731 free_reserved_area(&__tcm_start, &__tcm_end, 0, "TCM link"); 732 #endif 733 734 poison_init_mem(__init_begin, __init_end - __init_begin); 735 if (!machine_is_integrator() && !machine_is_cintegrator()) 736 free_initmem_default(0); 737 } 738 739 #ifdef CONFIG_BLK_DEV_INITRD 740 741 static int keep_initrd; 742 743 void free_initrd_mem(unsigned long start, unsigned long end) 744 { 745 if (!keep_initrd) { 746 poison_init_mem((void *)start, PAGE_ALIGN(end) - start); 747 free_reserved_area(start, end, 0, "initrd"); 748 } 749 } 750 751 static int __init keepinitrd_setup(char *__unused) 752 { 753 keep_initrd = 1; 754 return 1; 755 } 756 757 __setup("keepinitrd", keepinitrd_setup); 758 #endif 759