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 24 #include <asm/mach-types.h> 25 #include <asm/memblock.h> 26 #include <asm/prom.h> 27 #include <asm/sections.h> 28 #include <asm/setup.h> 29 #include <asm/sizes.h> 30 #include <asm/tlb.h> 31 #include <asm/fixmap.h> 32 33 #include <asm/mach/arch.h> 34 #include <asm/mach/map.h> 35 36 #include "mm.h" 37 38 static unsigned long phys_initrd_start __initdata = 0; 39 static unsigned long phys_initrd_size __initdata = 0; 40 41 static int __init early_initrd(char *p) 42 { 43 unsigned long start, size; 44 char *endp; 45 46 start = memparse(p, &endp); 47 if (*endp == ',') { 48 size = memparse(endp + 1, NULL); 49 50 phys_initrd_start = start; 51 phys_initrd_size = size; 52 } 53 return 0; 54 } 55 early_param("initrd", early_initrd); 56 57 static int __init parse_tag_initrd(const struct tag *tag) 58 { 59 printk(KERN_WARNING "ATAG_INITRD is deprecated; " 60 "please update your bootloader.\n"); 61 phys_initrd_start = __virt_to_phys(tag->u.initrd.start); 62 phys_initrd_size = tag->u.initrd.size; 63 return 0; 64 } 65 66 __tagtable(ATAG_INITRD, parse_tag_initrd); 67 68 static int __init parse_tag_initrd2(const struct tag *tag) 69 { 70 phys_initrd_start = tag->u.initrd.start; 71 phys_initrd_size = tag->u.initrd.size; 72 return 0; 73 } 74 75 __tagtable(ATAG_INITRD2, parse_tag_initrd2); 76 77 #ifdef CONFIG_OF_FLATTREE 78 void __init early_init_dt_setup_initrd_arch(unsigned long start, unsigned long end) 79 { 80 phys_initrd_start = start; 81 phys_initrd_size = end - start; 82 } 83 #endif /* CONFIG_OF_FLATTREE */ 84 85 /* 86 * This keeps memory configuration data used by a couple memory 87 * initialization functions, as well as show_mem() for the skipping 88 * of holes in the memory map. It is populated by arm_add_memory(). 89 */ 90 struct meminfo meminfo; 91 92 void show_mem(unsigned int filter) 93 { 94 int free = 0, total = 0, reserved = 0; 95 int shared = 0, cached = 0, slab = 0, i; 96 struct meminfo * mi = &meminfo; 97 98 printk("Mem-info:\n"); 99 show_free_areas(filter); 100 101 for_each_bank (i, mi) { 102 struct membank *bank = &mi->bank[i]; 103 unsigned int pfn1, pfn2; 104 struct page *page, *end; 105 106 pfn1 = bank_pfn_start(bank); 107 pfn2 = bank_pfn_end(bank); 108 109 page = pfn_to_page(pfn1); 110 end = pfn_to_page(pfn2 - 1) + 1; 111 112 do { 113 total++; 114 if (PageReserved(page)) 115 reserved++; 116 else if (PageSwapCache(page)) 117 cached++; 118 else if (PageSlab(page)) 119 slab++; 120 else if (!page_count(page)) 121 free++; 122 else 123 shared += page_count(page) - 1; 124 page++; 125 } while (page < end); 126 } 127 128 printk("%d pages of RAM\n", total); 129 printk("%d free pages\n", free); 130 printk("%d reserved pages\n", reserved); 131 printk("%d slab pages\n", slab); 132 printk("%d pages shared\n", shared); 133 printk("%d pages swap cached\n", cached); 134 } 135 136 static void __init find_limits(unsigned long *min, unsigned long *max_low, 137 unsigned long *max_high) 138 { 139 struct meminfo *mi = &meminfo; 140 int i; 141 142 /* This assumes the meminfo array is properly sorted */ 143 *min = bank_pfn_start(&mi->bank[0]); 144 for_each_bank (i, mi) 145 if (mi->bank[i].highmem) 146 break; 147 *max_low = bank_pfn_end(&mi->bank[i - 1]); 148 *max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]); 149 } 150 151 static void __init arm_bootmem_init(unsigned long start_pfn, 152 unsigned long end_pfn) 153 { 154 struct memblock_region *reg; 155 unsigned int boot_pages; 156 phys_addr_t bitmap; 157 pg_data_t *pgdat; 158 159 /* 160 * Allocate the bootmem bitmap page. This must be in a region 161 * of memory which has already been mapped. 162 */ 163 boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn); 164 bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES, 165 __pfn_to_phys(end_pfn)); 166 167 /* 168 * Initialise the bootmem allocator, handing the 169 * memory banks over to bootmem. 170 */ 171 node_set_online(0); 172 pgdat = NODE_DATA(0); 173 init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn); 174 175 /* Free the lowmem regions from memblock into bootmem. */ 176 for_each_memblock(memory, reg) { 177 unsigned long start = memblock_region_memory_base_pfn(reg); 178 unsigned long end = memblock_region_memory_end_pfn(reg); 179 180 if (end >= end_pfn) 181 end = end_pfn; 182 if (start >= end) 183 break; 184 185 free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT); 186 } 187 188 /* Reserve the lowmem memblock reserved regions in bootmem. */ 189 for_each_memblock(reserved, reg) { 190 unsigned long start = memblock_region_reserved_base_pfn(reg); 191 unsigned long end = memblock_region_reserved_end_pfn(reg); 192 193 if (end >= end_pfn) 194 end = end_pfn; 195 if (start >= end) 196 break; 197 198 reserve_bootmem(__pfn_to_phys(start), 199 (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT); 200 } 201 } 202 203 #ifdef CONFIG_ZONE_DMA 204 205 unsigned long arm_dma_zone_size __read_mostly; 206 EXPORT_SYMBOL(arm_dma_zone_size); 207 208 /* 209 * The DMA mask corresponding to the maximum bus address allocatable 210 * using GFP_DMA. The default here places no restriction on DMA 211 * allocations. This must be the smallest DMA mask in the system, 212 * so a successful GFP_DMA allocation will always satisfy this. 213 */ 214 u32 arm_dma_limit; 215 216 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole, 217 unsigned long dma_size) 218 { 219 if (size[0] <= dma_size) 220 return; 221 222 size[ZONE_NORMAL] = size[0] - dma_size; 223 size[ZONE_DMA] = dma_size; 224 hole[ZONE_NORMAL] = hole[0]; 225 hole[ZONE_DMA] = 0; 226 } 227 #endif 228 229 static void __init arm_bootmem_free(unsigned long min, unsigned long max_low, 230 unsigned long max_high) 231 { 232 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; 233 struct memblock_region *reg; 234 235 /* 236 * initialise the zones. 237 */ 238 memset(zone_size, 0, sizeof(zone_size)); 239 240 /* 241 * The memory size has already been determined. If we need 242 * to do anything fancy with the allocation of this memory 243 * to the zones, now is the time to do it. 244 */ 245 zone_size[0] = max_low - min; 246 #ifdef CONFIG_HIGHMEM 247 zone_size[ZONE_HIGHMEM] = max_high - max_low; 248 #endif 249 250 /* 251 * Calculate the size of the holes. 252 * holes = node_size - sum(bank_sizes) 253 */ 254 memcpy(zhole_size, zone_size, sizeof(zhole_size)); 255 for_each_memblock(memory, reg) { 256 unsigned long start = memblock_region_memory_base_pfn(reg); 257 unsigned long end = memblock_region_memory_end_pfn(reg); 258 259 if (start < max_low) { 260 unsigned long low_end = min(end, max_low); 261 zhole_size[0] -= low_end - start; 262 } 263 #ifdef CONFIG_HIGHMEM 264 if (end > max_low) { 265 unsigned long high_start = max(start, max_low); 266 zhole_size[ZONE_HIGHMEM] -= end - high_start; 267 } 268 #endif 269 } 270 271 #ifdef CONFIG_ZONE_DMA 272 /* 273 * Adjust the sizes according to any special requirements for 274 * this machine type. 275 */ 276 if (arm_dma_zone_size) { 277 arm_adjust_dma_zone(zone_size, zhole_size, 278 arm_dma_zone_size >> PAGE_SHIFT); 279 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1; 280 } else 281 arm_dma_limit = 0xffffffff; 282 #endif 283 284 free_area_init_node(0, zone_size, min, zhole_size); 285 } 286 287 #ifdef CONFIG_HAVE_ARCH_PFN_VALID 288 int pfn_valid(unsigned long pfn) 289 { 290 return memblock_is_memory(__pfn_to_phys(pfn)); 291 } 292 EXPORT_SYMBOL(pfn_valid); 293 #endif 294 295 #ifndef CONFIG_SPARSEMEM 296 static void __init arm_memory_present(void) 297 { 298 } 299 #else 300 static void __init arm_memory_present(void) 301 { 302 struct memblock_region *reg; 303 304 for_each_memblock(memory, reg) 305 memory_present(0, memblock_region_memory_base_pfn(reg), 306 memblock_region_memory_end_pfn(reg)); 307 } 308 #endif 309 310 static bool arm_memblock_steal_permitted = true; 311 312 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align) 313 { 314 phys_addr_t phys; 315 316 BUG_ON(!arm_memblock_steal_permitted); 317 318 phys = memblock_alloc(size, align); 319 memblock_free(phys, size); 320 memblock_remove(phys, size); 321 322 return phys; 323 } 324 325 void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc) 326 { 327 int i; 328 329 for (i = 0; i < mi->nr_banks; i++) 330 memblock_add(mi->bank[i].start, mi->bank[i].size); 331 332 /* Register the kernel text, kernel data and initrd with memblock. */ 333 #ifdef CONFIG_XIP_KERNEL 334 memblock_reserve(__pa(_sdata), _end - _sdata); 335 #else 336 memblock_reserve(__pa(_stext), _end - _stext); 337 #endif 338 #ifdef CONFIG_BLK_DEV_INITRD 339 if (phys_initrd_size && 340 !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) { 341 pr_err("INITRD: 0x%08lx+0x%08lx is not a memory region - disabling initrd\n", 342 phys_initrd_start, phys_initrd_size); 343 phys_initrd_start = phys_initrd_size = 0; 344 } 345 if (phys_initrd_size && 346 memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) { 347 pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n", 348 phys_initrd_start, phys_initrd_size); 349 phys_initrd_start = phys_initrd_size = 0; 350 } 351 if (phys_initrd_size) { 352 memblock_reserve(phys_initrd_start, phys_initrd_size); 353 354 /* Now convert initrd to virtual addresses */ 355 initrd_start = __phys_to_virt(phys_initrd_start); 356 initrd_end = initrd_start + phys_initrd_size; 357 } 358 #endif 359 360 arm_mm_memblock_reserve(); 361 arm_dt_memblock_reserve(); 362 363 /* reserve any platform specific memblock areas */ 364 if (mdesc->reserve) 365 mdesc->reserve(); 366 367 arm_memblock_steal_permitted = false; 368 memblock_allow_resize(); 369 memblock_dump_all(); 370 } 371 372 void __init bootmem_init(void) 373 { 374 unsigned long min, max_low, max_high; 375 376 max_low = max_high = 0; 377 378 find_limits(&min, &max_low, &max_high); 379 380 arm_bootmem_init(min, max_low); 381 382 /* 383 * Sparsemem tries to allocate bootmem in memory_present(), 384 * so must be done after the fixed reservations 385 */ 386 arm_memory_present(); 387 388 /* 389 * sparse_init() needs the bootmem allocator up and running. 390 */ 391 sparse_init(); 392 393 /* 394 * Now free the memory - free_area_init_node needs 395 * the sparse mem_map arrays initialized by sparse_init() 396 * for memmap_init_zone(), otherwise all PFNs are invalid. 397 */ 398 arm_bootmem_free(min, max_low, max_high); 399 400 /* 401 * This doesn't seem to be used by the Linux memory manager any 402 * more, but is used by ll_rw_block. If we can get rid of it, we 403 * also get rid of some of the stuff above as well. 404 * 405 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in 406 * the system, not the maximum PFN. 407 */ 408 max_low_pfn = max_low - PHYS_PFN_OFFSET; 409 max_pfn = max_high - PHYS_PFN_OFFSET; 410 } 411 412 static inline int free_area(unsigned long pfn, unsigned long end, char *s) 413 { 414 unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10); 415 416 for (; pfn < end; pfn++) { 417 struct page *page = pfn_to_page(pfn); 418 ClearPageReserved(page); 419 init_page_count(page); 420 __free_page(page); 421 pages++; 422 } 423 424 if (size && s) 425 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size); 426 427 return pages; 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 static void __init free_highpages(void) 523 { 524 #ifdef CONFIG_HIGHMEM 525 unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET; 526 struct memblock_region *mem, *res; 527 528 /* set highmem page free */ 529 for_each_memblock(memory, mem) { 530 unsigned long start = memblock_region_memory_base_pfn(mem); 531 unsigned long end = memblock_region_memory_end_pfn(mem); 532 533 /* Ignore complete lowmem entries */ 534 if (end <= max_low) 535 continue; 536 537 /* Truncate partial highmem entries */ 538 if (start < max_low) 539 start = max_low; 540 541 /* Find and exclude any reserved regions */ 542 for_each_memblock(reserved, res) { 543 unsigned long res_start, res_end; 544 545 res_start = memblock_region_reserved_base_pfn(res); 546 res_end = memblock_region_reserved_end_pfn(res); 547 548 if (res_end < start) 549 continue; 550 if (res_start < start) 551 res_start = start; 552 if (res_start > end) 553 res_start = end; 554 if (res_end > end) 555 res_end = end; 556 if (res_start != start) 557 totalhigh_pages += free_area(start, res_start, 558 NULL); 559 start = res_end; 560 if (start == end) 561 break; 562 } 563 564 /* And now free anything which remains */ 565 if (start < end) 566 totalhigh_pages += free_area(start, end, NULL); 567 } 568 totalram_pages += totalhigh_pages; 569 #endif 570 } 571 572 /* 573 * mem_init() marks the free areas in the mem_map and tells us how much 574 * memory is free. This is done after various parts of the system have 575 * claimed their memory after the kernel image. 576 */ 577 void __init mem_init(void) 578 { 579 unsigned long reserved_pages, free_pages; 580 struct memblock_region *reg; 581 int i; 582 #ifdef CONFIG_HAVE_TCM 583 /* These pointers are filled in on TCM detection */ 584 extern u32 dtcm_end; 585 extern u32 itcm_end; 586 #endif 587 588 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map; 589 590 /* this will put all unused low memory onto the freelists */ 591 free_unused_memmap(&meminfo); 592 593 totalram_pages += free_all_bootmem(); 594 595 #ifdef CONFIG_SA1111 596 /* now that our DMA memory is actually so designated, we can free it */ 597 totalram_pages += free_area(PHYS_PFN_OFFSET, 598 __phys_to_pfn(__pa(swapper_pg_dir)), NULL); 599 #endif 600 601 free_highpages(); 602 603 reserved_pages = free_pages = 0; 604 605 for_each_bank(i, &meminfo) { 606 struct membank *bank = &meminfo.bank[i]; 607 unsigned int pfn1, pfn2; 608 struct page *page, *end; 609 610 pfn1 = bank_pfn_start(bank); 611 pfn2 = bank_pfn_end(bank); 612 613 page = pfn_to_page(pfn1); 614 end = pfn_to_page(pfn2 - 1) + 1; 615 616 do { 617 if (PageReserved(page)) 618 reserved_pages++; 619 else if (!page_count(page)) 620 free_pages++; 621 page++; 622 } while (page < end); 623 } 624 625 /* 626 * Since our memory may not be contiguous, calculate the 627 * real number of pages we have in this system 628 */ 629 printk(KERN_INFO "Memory:"); 630 num_physpages = 0; 631 for_each_memblock(memory, reg) { 632 unsigned long pages = memblock_region_memory_end_pfn(reg) - 633 memblock_region_memory_base_pfn(reg); 634 num_physpages += pages; 635 printk(" %ldMB", pages >> (20 - PAGE_SHIFT)); 636 } 637 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT)); 638 639 printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n", 640 nr_free_pages() << (PAGE_SHIFT-10), 641 free_pages << (PAGE_SHIFT-10), 642 reserved_pages << (PAGE_SHIFT-10), 643 totalhigh_pages << (PAGE_SHIFT-10)); 644 645 #define MLK(b, t) b, t, ((t) - (b)) >> 10 646 #define MLM(b, t) b, t, ((t) - (b)) >> 20 647 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) 648 649 printk(KERN_NOTICE "Virtual kernel memory layout:\n" 650 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n" 651 #ifdef CONFIG_HAVE_TCM 652 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n" 653 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n" 654 #endif 655 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" 656 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" 657 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" 658 #ifdef CONFIG_HIGHMEM 659 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n" 660 #endif 661 #ifdef CONFIG_MODULES 662 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n" 663 #endif 664 " .text : 0x%p" " - 0x%p" " (%4d kB)\n" 665 " .init : 0x%p" " - 0x%p" " (%4d kB)\n" 666 " .data : 0x%p" " - 0x%p" " (%4d kB)\n" 667 " .bss : 0x%p" " - 0x%p" " (%4d kB)\n", 668 669 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) + 670 (PAGE_SIZE)), 671 #ifdef CONFIG_HAVE_TCM 672 MLK(DTCM_OFFSET, (unsigned long) dtcm_end), 673 MLK(ITCM_OFFSET, (unsigned long) itcm_end), 674 #endif 675 MLK(FIXADDR_START, FIXADDR_TOP), 676 MLM(VMALLOC_START, VMALLOC_END), 677 MLM(PAGE_OFFSET, (unsigned long)high_memory), 678 #ifdef CONFIG_HIGHMEM 679 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) * 680 (PAGE_SIZE)), 681 #endif 682 #ifdef CONFIG_MODULES 683 MLM(MODULES_VADDR, MODULES_END), 684 #endif 685 686 MLK_ROUNDUP(_text, _etext), 687 MLK_ROUNDUP(__init_begin, __init_end), 688 MLK_ROUNDUP(_sdata, _edata), 689 MLK_ROUNDUP(__bss_start, __bss_stop)); 690 691 #undef MLK 692 #undef MLM 693 #undef MLK_ROUNDUP 694 695 /* 696 * Check boundaries twice: Some fundamental inconsistencies can 697 * be detected at build time already. 698 */ 699 #ifdef CONFIG_MMU 700 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); 701 BUG_ON(TASK_SIZE > MODULES_VADDR); 702 #endif 703 704 #ifdef CONFIG_HIGHMEM 705 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); 706 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); 707 #endif 708 709 if (PAGE_SIZE >= 16384 && num_physpages <= 128) { 710 extern int sysctl_overcommit_memory; 711 /* 712 * On a machine this small we won't get 713 * anywhere without overcommit, so turn 714 * it on by default. 715 */ 716 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; 717 } 718 } 719 720 void free_initmem(void) 721 { 722 #ifdef CONFIG_HAVE_TCM 723 extern char __tcm_start, __tcm_end; 724 725 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start); 726 totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)), 727 __phys_to_pfn(__pa(&__tcm_end)), 728 "TCM link"); 729 #endif 730 731 poison_init_mem(__init_begin, __init_end - __init_begin); 732 if (!machine_is_integrator() && !machine_is_cintegrator()) 733 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)), 734 __phys_to_pfn(__pa(__init_end)), 735 "init"); 736 } 737 738 #ifdef CONFIG_BLK_DEV_INITRD 739 740 static int keep_initrd; 741 742 void free_initrd_mem(unsigned long start, unsigned long end) 743 { 744 if (!keep_initrd) { 745 poison_init_mem((void *)start, PAGE_ALIGN(end) - start); 746 totalram_pages += free_area(__phys_to_pfn(__pa(start)), 747 __phys_to_pfn(__pa(end)), 748 "initrd"); 749 } 750 } 751 752 static int __init keepinitrd_setup(char *__unused) 753 { 754 keep_initrd = 1; 755 return 1; 756 } 757 758 __setup("keepinitrd", keepinitrd_setup); 759 #endif 760