init.c 16.3 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3
/*
 *  linux/arch/arm/mm/init.c
 *
R
Russell King 已提交
4
 *  Copyright (C) 1995-2005 Russell King
L
Linus Torvalds 已提交
5 6 7 8 9 10 11 12 13 14 15
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mman.h>
16
#include <linux/export.h>
L
Linus Torvalds 已提交
17 18
#include <linux/nodemask.h>
#include <linux/initrd.h>
G
Grant Likely 已提交
19
#include <linux/of_fdt.h>
20
#include <linux/highmem.h>
21
#include <linux/gfp.h>
R
Russell King 已提交
22
#include <linux/memblock.h>
23
#include <linux/dma-contiguous.h>
24
#include <linux/sizes.h>
L
Linus Torvalds 已提交
25 26

#include <asm/mach-types.h>
27
#include <asm/memblock.h>
28
#include <asm/prom.h>
R
Russell King 已提交
29
#include <asm/sections.h>
L
Linus Torvalds 已提交
30 31
#include <asm/setup.h>
#include <asm/tlb.h>
32
#include <asm/fixmap.h>
L
Linus Torvalds 已提交
33 34 35 36

#include <asm/mach/arch.h>
#include <asm/mach/map.h>

37 38
#include "mm.h"

39
static phys_addr_t phys_initrd_start __initdata = 0;
40 41
static unsigned long phys_initrd_size __initdata = 0;

42
static int __init early_initrd(char *p)
43
{
44 45
	phys_addr_t start;
	unsigned long size;
46
	char *endp;
47

48 49 50
	start = memparse(p, &endp);
	if (*endp == ',') {
		size = memparse(endp + 1, NULL);
51 52 53 54

		phys_initrd_start = start;
		phys_initrd_size = size;
	}
55
	return 0;
56
}
57
early_param("initrd", early_initrd);
58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77

static int __init parse_tag_initrd(const struct tag *tag)
{
	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
		"please update your bootloader.\n");
	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
	phys_initrd_size = tag->u.initrd.size;
	return 0;
}

__tagtable(ATAG_INITRD, parse_tag_initrd);

static int __init parse_tag_initrd2(const struct tag *tag)
{
	phys_initrd_start = tag->u.initrd.start;
	phys_initrd_size = tag->u.initrd.size;
	return 0;
}

__tagtable(ATAG_INITRD2, parse_tag_initrd2);
L
Linus Torvalds 已提交
78 79

/*
80 81 82
 * This keeps memory configuration data used by a couple memory
 * initialization functions, as well as show_mem() for the skipping
 * of holes in the memory map.  It is populated by arm_add_memory().
L
Linus Torvalds 已提交
83
 */
84
struct meminfo meminfo;
85

86
void show_mem(unsigned int filter)
L
Linus Torvalds 已提交
87 88
{
	int free = 0, total = 0, reserved = 0;
R
Russell King 已提交
89
	int shared = 0, cached = 0, slab = 0, i;
90
	struct meminfo * mi = &meminfo;
L
Linus Torvalds 已提交
91 92

	printk("Mem-info:\n");
93
	show_free_areas(filter);
R
Russell King 已提交
94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119

	for_each_bank (i, mi) {
		struct membank *bank = &mi->bank[i];
		unsigned int pfn1, pfn2;
		struct page *page, *end;

		pfn1 = bank_pfn_start(bank);
		pfn2 = bank_pfn_end(bank);

		page = pfn_to_page(pfn1);
		end  = pfn_to_page(pfn2 - 1) + 1;

		do {
			total++;
			if (PageReserved(page))
				reserved++;
			else if (PageSwapCache(page))
				cached++;
			else if (PageSlab(page))
				slab++;
			else if (!page_count(page))
				free++;
			else
				shared += page_count(page) - 1;
			page++;
		} while (page < end);
L
Linus Torvalds 已提交
120 121 122 123 124 125 126 127 128 129
	}

	printk("%d pages of RAM\n", total);
	printk("%d free pages\n", free);
	printk("%d reserved pages\n", reserved);
	printk("%d slab pages\n", slab);
	printk("%d pages shared\n", shared);
	printk("%d pages swap cached\n", cached);
}

130
static void __init find_limits(unsigned long *min, unsigned long *max_low,
131
			       unsigned long *max_high)
R
Russell King 已提交
132
{
133
	struct meminfo *mi = &meminfo;
R
Russell King 已提交
134 135
	int i;

136 137 138 139 140 141 142
	/* This assumes the meminfo array is properly sorted */
	*min = bank_pfn_start(&mi->bank[0]);
	for_each_bank (i, mi)
		if (mi->bank[i].highmem)
				break;
	*max_low = bank_pfn_end(&mi->bank[i - 1]);
	*max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
R
Russell King 已提交
143 144
}

145
#ifdef CONFIG_ZONE_DMA
146

147
phys_addr_t arm_dma_zone_size __read_mostly;
148 149
EXPORT_SYMBOL(arm_dma_zone_size);

150 151 152 153 154 155
/*
 * The DMA mask corresponding to the maximum bus address allocatable
 * using GFP_DMA.  The default here places no restriction on DMA
 * allocations.  This must be the smallest DMA mask in the system,
 * so a successful GFP_DMA allocation will always satisfy this.
 */
156
phys_addr_t arm_dma_limit;
157
unsigned long arm_dma_pfn_limit;
158

159 160 161 162 163 164 165 166 167 168 169 170 171
static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
	unsigned long dma_size)
{
	if (size[0] <= dma_size)
		return;

	size[ZONE_NORMAL] = size[0] - dma_size;
	size[ZONE_DMA] = dma_size;
	hole[ZONE_NORMAL] = hole[0];
	hole[ZONE_DMA] = 0;
}
#endif

172
void __init setup_dma_zone(const struct machine_desc *mdesc)
173 174 175 176
{
#ifdef CONFIG_ZONE_DMA
	if (mdesc->dma_zone_size) {
		arm_dma_zone_size = mdesc->dma_zone_size;
177
		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
178 179
	} else
		arm_dma_limit = 0xffffffff;
180
	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
181 182 183
#endif
}

184
static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
185
	unsigned long max_high)
186 187
{
	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
188
	struct memblock_region *reg;
189

R
Russell King 已提交
190
	/*
R
Russell King 已提交
191
	 * initialise the zones.
R
Russell King 已提交
192 193 194 195
	 */
	memset(zone_size, 0, sizeof(zone_size));

	/*
R
Russell King 已提交
196 197 198
	 * The memory size has already been determined.  If we need
	 * to do anything fancy with the allocation of this memory
	 * to the zones, now is the time to do it.
R
Russell King 已提交
199
	 */
R
Russell King 已提交
200 201 202 203
	zone_size[0] = max_low - min;
#ifdef CONFIG_HIGHMEM
	zone_size[ZONE_HIGHMEM] = max_high - max_low;
#endif
R
Russell King 已提交
204 205

	/*
R
Russell King 已提交
206 207
	 * Calculate the size of the holes.
	 *  holes = node_size - sum(bank_sizes)
R
Russell King 已提交
208
	 */
R
Russell King 已提交
209
	memcpy(zhole_size, zone_size, sizeof(zhole_size));
210 211 212 213 214 215 216 217
	for_each_memblock(memory, reg) {
		unsigned long start = memblock_region_memory_base_pfn(reg);
		unsigned long end = memblock_region_memory_end_pfn(reg);

		if (start < max_low) {
			unsigned long low_end = min(end, max_low);
			zhole_size[0] -= low_end - start;
		}
R
Russell King 已提交
218
#ifdef CONFIG_HIGHMEM
219 220 221 222
		if (end > max_low) {
			unsigned long high_start = max(start, max_low);
			zhole_size[ZONE_HIGHMEM] -= end - high_start;
		}
R
Russell King 已提交
223 224
#endif
	}
R
Russell King 已提交
225

226
#ifdef CONFIG_ZONE_DMA
R
Russell King 已提交
227 228 229 230
	/*
	 * Adjust the sizes according to any special requirements for
	 * this machine type.
	 */
231
	if (arm_dma_zone_size)
232 233
		arm_adjust_dma_zone(zone_size, zhole_size,
			arm_dma_zone_size >> PAGE_SHIFT);
234
#endif
R
Russell King 已提交
235

R
Russell King 已提交
236
	free_area_init_node(0, zone_size, min, zhole_size);
L
Linus Torvalds 已提交
237 238
}

239
#ifdef CONFIG_HAVE_ARCH_PFN_VALID
240 241
int pfn_valid(unsigned long pfn)
{
242
	return memblock_is_memory(__pfn_to_phys(pfn));
243 244
}
EXPORT_SYMBOL(pfn_valid);
245
#endif
246

247
#ifndef CONFIG_SPARSEMEM
248
static void __init arm_memory_present(void)
249 250 251
{
}
#else
252
static void __init arm_memory_present(void)
253
{
254 255
	struct memblock_region *reg;

256
	for_each_memblock(memory, reg)
257 258
		memory_present(0, memblock_region_memory_base_pfn(reg),
			       memblock_region_memory_end_pfn(reg));
259
}
260 261
#endif

262 263
static bool arm_memblock_steal_permitted = true;

264
phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
265 266 267 268 269
{
	phys_addr_t phys;

	BUG_ON(!arm_memblock_steal_permitted);

270
	phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
271 272 273 274 275 276
	memblock_free(phys, size);
	memblock_remove(phys, size);

	return phys;
}

277 278
void __init arm_memblock_init(struct meminfo *mi,
	const struct machine_desc *mdesc)
R
Russell King 已提交
279 280 281 282 283 284 285 286
{
	int i;

	for (i = 0; i < mi->nr_banks; i++)
		memblock_add(mi->bank[i].start, mi->bank[i].size);

	/* Register the kernel text, kernel data and initrd with memblock. */
#ifdef CONFIG_XIP_KERNEL
287
	memblock_reserve(__pa(_sdata), _end - _sdata);
R
Russell King 已提交
288 289 290 291
#else
	memblock_reserve(__pa(_stext), _end - _stext);
#endif
#ifdef CONFIG_BLK_DEV_INITRD
292
	/* FDT scan will populate initrd_start */
293
	if (initrd_start && !phys_initrd_size) {
294 295 296
		phys_initrd_start = __virt_to_phys(initrd_start);
		phys_initrd_size = initrd_end - initrd_start;
	}
297
	initrd_start = initrd_end = 0;
298 299
	if (phys_initrd_size &&
	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
300 301
		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
		       (u64)phys_initrd_start, phys_initrd_size);
302 303
		phys_initrd_start = phys_initrd_size = 0;
	}
304 305
	if (phys_initrd_size &&
	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
306 307
		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
		       (u64)phys_initrd_start, phys_initrd_size);
308 309
		phys_initrd_start = phys_initrd_size = 0;
	}
R
Russell King 已提交
310 311 312 313 314 315 316 317 318 319
	if (phys_initrd_size) {
		memblock_reserve(phys_initrd_start, phys_initrd_size);

		/* Now convert initrd to virtual addresses */
		initrd_start = __phys_to_virt(phys_initrd_start);
		initrd_end = initrd_start + phys_initrd_size;
	}
#endif

	arm_mm_memblock_reserve();
320
	arm_dt_memblock_reserve();
R
Russell King 已提交
321

322 323 324 325
	/* reserve any platform specific memblock areas */
	if (mdesc->reserve)
		mdesc->reserve();

326 327 328 329 330 331
	/*
	 * reserve memory for DMA contigouos allocations,
	 * must come from DMA area inside low memory
	 */
	dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));

332
	arm_memblock_steal_permitted = false;
R
Russell King 已提交
333 334 335
	memblock_dump_all();
}

336
void __init bootmem_init(void)
L
Linus Torvalds 已提交
337
{
R
Russell King 已提交
338
	unsigned long min, max_low, max_high;
L
Linus Torvalds 已提交
339

340
	memblock_allow_resize();
R
Russell King 已提交
341 342
	max_low = max_high = 0;

343
	find_limits(&min, &max_low, &max_high);
R
Russell King 已提交
344

R
Russell King 已提交
345 346 347 348
	/*
	 * Sparsemem tries to allocate bootmem in memory_present(),
	 * so must be done after the fixed reservations
	 */
349
	arm_memory_present();
L
Linus Torvalds 已提交
350

351 352 353 354 355 356
	/*
	 * sparse_init() needs the bootmem allocator up and running.
	 */
	sparse_init();

	/*
R
Russell King 已提交
357
	 * Now free the memory - free_area_init_node needs
358 359 360
	 * the sparse mem_map arrays initialized by sparse_init()
	 * for memmap_init_zone(), otherwise all PFNs are invalid.
	 */
361
	zone_sizes_init(min, max_low, max_high);
362

R
Russell King 已提交
363 364 365 366 367
	/*
	 * This doesn't seem to be used by the Linux memory manager any
	 * more, but is used by ll_rw_block.  If we can get rid of it, we
	 * also get rid of some of the stuff above as well.
	 */
368 369 370
	min_low_pfn = min;
	max_low_pfn = max_low;
	max_pfn = max_high;
R
Russell King 已提交
371
}
L
Linus Torvalds 已提交
372

373 374 375 376 377 378 379
/*
 * Poison init memory with an undefined instruction (ARM) or a branch to an
 * undefined instruction (Thumb).
 */
static inline void poison_init_mem(void *s, size_t count)
{
	u32 *p = (u32 *)s;
380
	for (; count != 0; count -= 4)
381 382 383
		*p++ = 0xe7fddef0;
}

384
static inline void
R
Russell King 已提交
385
free_memmap(unsigned long start_pfn, unsigned long end_pfn)
386 387
{
	struct page *start_pg, *end_pg;
388
	phys_addr_t pg, pgend;
389 390 391 392

	/*
	 * Convert start_pfn/end_pfn to a struct page pointer.
	 */
393
	start_pg = pfn_to_page(start_pfn - 1) + 1;
394
	end_pg = pfn_to_page(end_pfn - 1) + 1;
395 396 397 398 399

	/*
	 * Convert to physical addresses, and
	 * round start upwards and end downwards.
	 */
400 401
	pg = PAGE_ALIGN(__pa(start_pg));
	pgend = __pa(end_pg) & PAGE_MASK;
402 403 404 405 406 407

	/*
	 * If there are free pages between these,
	 * free the section of the memmap array.
	 */
	if (pg < pgend)
408
		memblock_free_early(pg, pgend - pg);
409 410 411 412 413
}

/*
 * The mem_map array can get very big.  Free the unused area of the memory map.
 */
R
Russell King 已提交
414
static void __init free_unused_memmap(struct meminfo *mi)
415 416 417 418 419
{
	unsigned long bank_start, prev_bank_end = 0;
	unsigned int i;

	/*
420 421
	 * This relies on each bank being in address order.
	 * The banks are sorted previously in bootmem_init().
422
	 */
R
Russell King 已提交
423
	for_each_bank(i, mi) {
424 425 426
		struct membank *bank = &mi->bank[i];

		bank_start = bank_pfn_start(bank);
427

428 429 430 431 432 433 434
#ifdef CONFIG_SPARSEMEM
		/*
		 * Take care not to free memmap entries that don't exist
		 * due to SPARSEMEM sections which aren't present.
		 */
		bank_start = min(bank_start,
				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
435 436 437 438 439 440 441
#else
		/*
		 * Align down here since the VM subsystem insists that the
		 * memmap entries are valid from the bank start aligned to
		 * MAX_ORDER_NR_PAGES.
		 */
		bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
442
#endif
443 444 445 446
		/*
		 * If we had a previous bank, and there is a space
		 * between the current bank and the previous, free it.
		 */
447
		if (prev_bank_end && prev_bank_end < bank_start)
R
Russell King 已提交
448
			free_memmap(prev_bank_end, bank_start);
449

450 451 452 453 454 455
		/*
		 * Align up here since the VM subsystem insists that the
		 * memmap entries are valid from the bank end aligned to
		 * MAX_ORDER_NR_PAGES.
		 */
		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
456
	}
457 458 459 460 461 462

#ifdef CONFIG_SPARSEMEM
	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
		free_memmap(prev_bank_end,
			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
#endif
463 464
}

465 466 467
#ifdef CONFIG_HIGHMEM
static inline void free_area_high(unsigned long pfn, unsigned long end)
{
468 469
	for (; pfn < end; pfn++)
		free_highmem_page(pfn_to_page(pfn));
470 471 472
}
#endif

473 474 475
static void __init free_highpages(void)
{
#ifdef CONFIG_HIGHMEM
476
	unsigned long max_low = max_low_pfn;
477
	struct memblock_region *mem, *res;
478 479

	/* set highmem page free */
480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507
	for_each_memblock(memory, mem) {
		unsigned long start = memblock_region_memory_base_pfn(mem);
		unsigned long end = memblock_region_memory_end_pfn(mem);

		/* Ignore complete lowmem entries */
		if (end <= max_low)
			continue;

		/* Truncate partial highmem entries */
		if (start < max_low)
			start = max_low;

		/* Find and exclude any reserved regions */
		for_each_memblock(reserved, res) {
			unsigned long res_start, res_end;

			res_start = memblock_region_reserved_base_pfn(res);
			res_end = memblock_region_reserved_end_pfn(res);

			if (res_end < start)
				continue;
			if (res_start < start)
				res_start = start;
			if (res_start > end)
				res_start = end;
			if (res_end > end)
				res_end = end;
			if (res_start != start)
508
				free_area_high(start, res_start);
509 510 511 512 513 514 515
			start = res_end;
			if (start == end)
				break;
		}

		/* And now free anything which remains */
		if (start < end)
516
			free_area_high(start, end);
517 518 519 520
	}
#endif
}

L
Linus Torvalds 已提交
521 522 523 524 525 526 527
/*
 * mem_init() marks the free areas in the mem_map and tells us how much
 * memory is free.  This is done after various parts of the system have
 * claimed their memory after the kernel image.
 */
void __init mem_init(void)
{
528 529 530 531 532
#ifdef CONFIG_HAVE_TCM
	/* These pointers are filled in on TCM detection */
	extern u32 dtcm_end;
	extern u32 itcm_end;
#endif
L
Linus Torvalds 已提交
533

534
	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
L
Linus Torvalds 已提交
535 536

	/* this will put all unused low memory onto the freelists */
R
Russell King 已提交
537
	free_unused_memmap(&meminfo);
538
	free_all_bootmem();
L
Linus Torvalds 已提交
539 540 541

#ifdef CONFIG_SA1111
	/* now that our DMA memory is actually so designated, we can free it */
542
	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
L
Linus Torvalds 已提交
543 544
#endif

545
	free_highpages();
546

547
	mem_init_print_info(NULL);
L
Linus Torvalds 已提交
548

549 550 551 552 553 554
#define MLK(b, t) b, t, ((t) - (b)) >> 10
#define MLM(b, t) b, t, ((t) - (b)) >> 20
#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)

	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
555 556 557 558
#ifdef CONFIG_HAVE_TCM
			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
#endif
559 560 561 562 563 564
			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
#ifdef CONFIG_HIGHMEM
			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
#endif
565
#ifdef CONFIG_MODULES
566
			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
567
#endif
568
			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
569
			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
570 571
			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
			"       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
572 573 574

			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
				(PAGE_SIZE)),
575
#ifdef CONFIG_HAVE_TCM
576 577
			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
578
#endif
579
			MLK(FIXADDR_START, FIXADDR_TOP),
580
			MLM(VMALLOC_START, VMALLOC_END),
581 582 583 584 585
			MLM(PAGE_OFFSET, (unsigned long)high_memory),
#ifdef CONFIG_HIGHMEM
			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
				(PAGE_SIZE)),
#endif
586
#ifdef CONFIG_MODULES
587
			MLM(MODULES_VADDR, MODULES_END),
588
#endif
589 590

			MLK_ROUNDUP(_text, _etext),
591
			MLK_ROUNDUP(__init_begin, __init_end),
592 593
			MLK_ROUNDUP(_sdata, _edata),
			MLK_ROUNDUP(__bss_start, __bss_stop));
594 595 596 597 598

#undef MLK
#undef MLM
#undef MLK_ROUNDUP

599 600 601 602 603 604 605 606 607 608 609 610 611 612
	/*
	 * Check boundaries twice: Some fundamental inconsistencies can
	 * be detected at build time already.
	 */
#ifdef CONFIG_MMU
	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
#endif

#ifdef CONFIG_HIGHMEM
	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
#endif

613
	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
L
Linus Torvalds 已提交
614 615 616 617 618 619 620 621 622 623 624 625
		extern int sysctl_overcommit_memory;
		/*
		 * On a machine this small we won't get
		 * anywhere without overcommit, so turn
		 * it on by default.
		 */
		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
	}
}

void free_initmem(void)
{
626
#ifdef CONFIG_HAVE_TCM
627
	extern char __tcm_start, __tcm_end;
628

629
	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
630
	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
631 632
#endif

633
	poison_init_mem(__init_begin, __init_end - __init_begin);
N
Nicolas Pitre 已提交
634
	if (!machine_is_integrator() && !machine_is_cintegrator())
635
		free_initmem_default(-1);
L
Linus Torvalds 已提交
636 637 638 639 640 641 642 643
}

#ifdef CONFIG_BLK_DEV_INITRD

static int keep_initrd;

void free_initrd_mem(unsigned long start, unsigned long end)
{
644 645
	if (!keep_initrd) {
		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
646
		free_reserved_area((void *)start, (void *)end, -1, "initrd");
647
	}
L
Linus Torvalds 已提交
648 649 650 651 652 653 654 655 656 657
}

static int __init keepinitrd_setup(char *__unused)
{
	keep_initrd = 1;
	return 1;
}

__setup("keepinitrd", keepinitrd_setup);
#endif