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v3.1
  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/nodemask.h>
 17#include <linux/initrd.h>
 18#include <linux/of_fdt.h>
 19#include <linux/highmem.h>
 20#include <linux/gfp.h>
 21#include <linux/memblock.h>
 22#include <linux/sort.h>
 
 23
 24#include <asm/mach-types.h>
 
 25#include <asm/prom.h>
 26#include <asm/sections.h>
 27#include <asm/setup.h>
 28#include <asm/sizes.h>
 29#include <asm/tlb.h>
 30#include <asm/fixmap.h>
 31
 32#include <asm/mach/arch.h>
 33#include <asm/mach/map.h>
 34
 35#include "mm.h"
 36
 37static unsigned long phys_initrd_start __initdata = 0;
 38static unsigned long phys_initrd_size __initdata = 0;
 39
 40static int __init early_initrd(char *p)
 41{
 42	unsigned long start, size;
 
 43	char *endp;
 44
 45	start = memparse(p, &endp);
 46	if (*endp == ',') {
 47		size = memparse(endp + 1, NULL);
 48
 49		phys_initrd_start = start;
 50		phys_initrd_size = size;
 51	}
 52	return 0;
 53}
 54early_param("initrd", early_initrd);
 55
 56static int __init parse_tag_initrd(const struct tag *tag)
 57{
 58	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
 59		"please update your bootloader.\n");
 60	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
 61	phys_initrd_size = tag->u.initrd.size;
 62	return 0;
 63}
 64
 65__tagtable(ATAG_INITRD, parse_tag_initrd);
 66
 67static int __init parse_tag_initrd2(const struct tag *tag)
 68{
 69	phys_initrd_start = tag->u.initrd.start;
 70	phys_initrd_size = tag->u.initrd.size;
 71	return 0;
 72}
 73
 74__tagtable(ATAG_INITRD2, parse_tag_initrd2);
 75
 76#ifdef CONFIG_OF_FLATTREE
 77void __init early_init_dt_setup_initrd_arch(unsigned long start, unsigned long end)
 78{
 79	phys_initrd_start = start;
 80	phys_initrd_size = end - start;
 81}
 82#endif /* CONFIG_OF_FLATTREE */
 83
 84/*
 85 * This keeps memory configuration data used by a couple memory
 86 * initialization functions, as well as show_mem() for the skipping
 87 * of holes in the memory map.  It is populated by arm_add_memory().
 88 */
 89struct meminfo meminfo;
 90
 91void show_mem(unsigned int filter)
 92{
 93	int free = 0, total = 0, reserved = 0;
 94	int shared = 0, cached = 0, slab = 0, i;
 95	struct meminfo * mi = &meminfo;
 96
 97	printk("Mem-info:\n");
 98	show_free_areas(filter);
 99
100	for_each_bank (i, mi) {
101		struct membank *bank = &mi->bank[i];
102		unsigned int pfn1, pfn2;
103		struct page *page, *end;
104
105		pfn1 = bank_pfn_start(bank);
106		pfn2 = bank_pfn_end(bank);
107
108		page = pfn_to_page(pfn1);
109		end  = pfn_to_page(pfn2 - 1) + 1;
110
111		do {
112			total++;
113			if (PageReserved(page))
114				reserved++;
115			else if (PageSwapCache(page))
116				cached++;
117			else if (PageSlab(page))
118				slab++;
119			else if (!page_count(page))
120				free++;
121			else
122				shared += page_count(page) - 1;
123			page++;
124		} while (page < end);
125	}
126
127	printk("%d pages of RAM\n", total);
128	printk("%d free pages\n", free);
129	printk("%d reserved pages\n", reserved);
130	printk("%d slab pages\n", slab);
131	printk("%d pages shared\n", shared);
132	printk("%d pages swap cached\n", cached);
133}
134
135static void __init find_limits(unsigned long *min, unsigned long *max_low,
136	unsigned long *max_high)
137{
138	struct meminfo *mi = &meminfo;
139	int i;
140
141	*min = -1UL;
142	*max_low = *max_high = 0;
143
144	for_each_bank (i, mi) {
145		struct membank *bank = &mi->bank[i];
146		unsigned long start, end;
147
148		start = bank_pfn_start(bank);
149		end = bank_pfn_end(bank);
150
151		if (*min > start)
152			*min = start;
153		if (*max_high < end)
154			*max_high = end;
155		if (bank->highmem)
156			continue;
157		if (*max_low < end)
158			*max_low = end;
159	}
160}
161
162static void __init arm_bootmem_init(unsigned long start_pfn,
163	unsigned long end_pfn)
164{
165	struct memblock_region *reg;
166	unsigned int boot_pages;
167	phys_addr_t bitmap;
168	pg_data_t *pgdat;
169
170	/*
171	 * Allocate the bootmem bitmap page.  This must be in a region
172	 * of memory which has already been mapped.
173	 */
174	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
175	bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
176				__pfn_to_phys(end_pfn));
177
178	/*
179	 * Initialise the bootmem allocator, handing the
180	 * memory banks over to bootmem.
181	 */
182	node_set_online(0);
183	pgdat = NODE_DATA(0);
184	init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
185
186	/* Free the lowmem regions from memblock into bootmem. */
187	for_each_memblock(memory, reg) {
188		unsigned long start = memblock_region_memory_base_pfn(reg);
189		unsigned long end = memblock_region_memory_end_pfn(reg);
190
191		if (end >= end_pfn)
192			end = end_pfn;
193		if (start >= end)
194			break;
195
196		free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
197	}
198
199	/* Reserve the lowmem memblock reserved regions in bootmem. */
200	for_each_memblock(reserved, reg) {
201		unsigned long start = memblock_region_reserved_base_pfn(reg);
202		unsigned long end = memblock_region_reserved_end_pfn(reg);
203
204		if (end >= end_pfn)
205			end = end_pfn;
206		if (start >= end)
207			break;
208
209		reserve_bootmem(__pfn_to_phys(start),
210			        (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
211	}
212}
213
214#ifdef CONFIG_ZONE_DMA
215
216unsigned long arm_dma_zone_size __read_mostly;
217EXPORT_SYMBOL(arm_dma_zone_size);
218
219/*
220 * The DMA mask corresponding to the maximum bus address allocatable
221 * using GFP_DMA.  The default here places no restriction on DMA
222 * allocations.  This must be the smallest DMA mask in the system,
223 * so a successful GFP_DMA allocation will always satisfy this.
224 */
225u32 arm_dma_limit;
 
226
227static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
228	unsigned long dma_size)
229{
230	if (size[0] <= dma_size)
231		return;
232
233	size[ZONE_NORMAL] = size[0] - dma_size;
234	size[ZONE_DMA] = dma_size;
235	hole[ZONE_NORMAL] = hole[0];
236	hole[ZONE_DMA] = 0;
237}
238#endif
239
240static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
 
 
 
 
 
 
 
 
 
 
 
 
241	unsigned long max_high)
242{
243	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
244	struct memblock_region *reg;
245
246	/*
247	 * initialise the zones.
248	 */
249	memset(zone_size, 0, sizeof(zone_size));
250
251	/*
252	 * The memory size has already been determined.  If we need
253	 * to do anything fancy with the allocation of this memory
254	 * to the zones, now is the time to do it.
255	 */
256	zone_size[0] = max_low - min;
257#ifdef CONFIG_HIGHMEM
258	zone_size[ZONE_HIGHMEM] = max_high - max_low;
259#endif
260
261	/*
262	 * Calculate the size of the holes.
263	 *  holes = node_size - sum(bank_sizes)
264	 */
265	memcpy(zhole_size, zone_size, sizeof(zhole_size));
266	for_each_memblock(memory, reg) {
267		unsigned long start = memblock_region_memory_base_pfn(reg);
268		unsigned long end = memblock_region_memory_end_pfn(reg);
269
270		if (start < max_low) {
271			unsigned long low_end = min(end, max_low);
272			zhole_size[0] -= low_end - start;
273		}
274#ifdef CONFIG_HIGHMEM
275		if (end > max_low) {
276			unsigned long high_start = max(start, max_low);
277			zhole_size[ZONE_HIGHMEM] -= end - high_start;
278		}
279#endif
280	}
281
282#ifdef CONFIG_ZONE_DMA
283	/*
284	 * Adjust the sizes according to any special requirements for
285	 * this machine type.
286	 */
287	if (arm_dma_zone_size) {
288		arm_adjust_dma_zone(zone_size, zhole_size,
289			arm_dma_zone_size >> PAGE_SHIFT);
290		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
291	} else
292		arm_dma_limit = 0xffffffff;
293#endif
294
295	free_area_init_node(0, zone_size, min, zhole_size);
296}
297
298#ifdef CONFIG_HAVE_ARCH_PFN_VALID
299int pfn_valid(unsigned long pfn)
300{
301	return memblock_is_memory(__pfn_to_phys(pfn));
302}
303EXPORT_SYMBOL(pfn_valid);
304#endif
305
306#ifndef CONFIG_SPARSEMEM
307static void arm_memory_present(void)
308{
309}
310#else
311static void arm_memory_present(void)
312{
313	struct memblock_region *reg;
314
315	for_each_memblock(memory, reg)
316		memory_present(0, memblock_region_memory_base_pfn(reg),
317			       memblock_region_memory_end_pfn(reg));
318}
319#endif
320
321static int __init meminfo_cmp(const void *_a, const void *_b)
 
 
322{
323	const struct membank *a = _a, *b = _b;
324	long cmp = bank_pfn_start(a) - bank_pfn_start(b);
325	return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
 
 
 
 
 
 
326}
327
328void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
 
329{
330	int i;
331
332	sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
333
334	memblock_init();
335	for (i = 0; i < mi->nr_banks; i++)
336		memblock_add(mi->bank[i].start, mi->bank[i].size);
337
338	/* Register the kernel text, kernel data and initrd with memblock. */
339#ifdef CONFIG_XIP_KERNEL
340	memblock_reserve(__pa(_sdata), _end - _sdata);
341#else
342	memblock_reserve(__pa(_stext), _end - _stext);
343#endif
344#ifdef CONFIG_BLK_DEV_INITRD
 
 
 
 
 
 
345	if (phys_initrd_size &&
346	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
347		pr_err("INITRD: 0x%08lx+0x%08lx is not a 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_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
353		pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use 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_reserve(phys_initrd_start, phys_initrd_size);
359
360		/* Now convert initrd to virtual addresses */
361		initrd_start = __phys_to_virt(phys_initrd_start);
362		initrd_end = initrd_start + phys_initrd_size;
363	}
364#endif
365
366	arm_mm_memblock_reserve();
367	arm_dt_memblock_reserve();
368
369	/* reserve any platform specific memblock areas */
370	if (mdesc->reserve)
371		mdesc->reserve();
372
373	memblock_analyze();
 
 
 
 
 
 
 
 
374	memblock_dump_all();
375}
376
377void __init bootmem_init(void)
378{
379	unsigned long min, max_low, max_high;
380
 
381	max_low = max_high = 0;
382
383	find_limits(&min, &max_low, &max_high);
384
385	arm_bootmem_init(min, max_low);
386
387	/*
388	 * Sparsemem tries to allocate bootmem in memory_present(),
389	 * so must be done after the fixed reservations
390	 */
391	arm_memory_present();
392
393	/*
394	 * sparse_init() needs the bootmem allocator up and running.
395	 */
396	sparse_init();
397
398	/*
399	 * Now free the memory - free_area_init_node needs
400	 * the sparse mem_map arrays initialized by sparse_init()
401	 * for memmap_init_zone(), otherwise all PFNs are invalid.
402	 */
403	arm_bootmem_free(min, max_low, max_high);
404
405	high_memory = __va(((phys_addr_t)max_low << PAGE_SHIFT) - 1) + 1;
406
407	/*
408	 * This doesn't seem to be used by the Linux memory manager any
409	 * more, but is used by ll_rw_block.  If we can get rid of it, we
410	 * also get rid of some of the stuff above as well.
411	 *
412	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
413	 * the system, not the maximum PFN.
414	 */
415	max_low_pfn = max_low - PHYS_PFN_OFFSET;
416	max_pfn = max_high - PHYS_PFN_OFFSET;
417}
418
419static inline int free_area(unsigned long pfn, unsigned long end, char *s)
420{
421	unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
422
423	for (; pfn < end; pfn++) {
424		struct page *page = pfn_to_page(pfn);
425		ClearPageReserved(page);
426		init_page_count(page);
427		__free_page(page);
428		pages++;
429	}
430
431	if (size && s)
432		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
433
434	return pages;
435}
436
437/*
438 * Poison init memory with an undefined instruction (ARM) or a branch to an
439 * undefined instruction (Thumb).
440 */
441static inline void poison_init_mem(void *s, size_t count)
442{
443	u32 *p = (u32 *)s;
444	for (; count != 0; count -= 4)
445		*p++ = 0xe7fddef0;
446}
447
448static inline void
449free_memmap(unsigned long start_pfn, unsigned long end_pfn)
450{
451	struct page *start_pg, *end_pg;
452	unsigned long pg, pgend;
453
454	/*
455	 * Convert start_pfn/end_pfn to a struct page pointer.
456	 */
457	start_pg = pfn_to_page(start_pfn - 1) + 1;
458	end_pg = pfn_to_page(end_pfn - 1) + 1;
459
460	/*
461	 * Convert to physical addresses, and
462	 * round start upwards and end downwards.
463	 */
464	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
465	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
466
467	/*
468	 * If there are free pages between these,
469	 * free the section of the memmap array.
470	 */
471	if (pg < pgend)
472		free_bootmem(pg, pgend - pg);
473}
474
475/*
476 * The mem_map array can get very big.  Free the unused area of the memory map.
477 */
478static void __init free_unused_memmap(struct meminfo *mi)
479{
480	unsigned long bank_start, prev_bank_end = 0;
481	unsigned int i;
482
483	/*
484	 * This relies on each bank being in address order.
485	 * The banks are sorted previously in bootmem_init().
486	 */
487	for_each_bank(i, mi) {
488		struct membank *bank = &mi->bank[i];
489
490		bank_start = bank_pfn_start(bank);
491
492#ifdef CONFIG_SPARSEMEM
493		/*
494		 * Take care not to free memmap entries that don't exist
495		 * due to SPARSEMEM sections which aren't present.
496		 */
497		bank_start = min(bank_start,
498				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
499#else
500		/*
501		 * Align down here since the VM subsystem insists that the
502		 * memmap entries are valid from the bank start aligned to
503		 * MAX_ORDER_NR_PAGES.
504		 */
505		bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
506#endif
507		/*
508		 * If we had a previous bank, and there is a space
509		 * between the current bank and the previous, free it.
510		 */
511		if (prev_bank_end && prev_bank_end < bank_start)
512			free_memmap(prev_bank_end, bank_start);
513
514		/*
515		 * Align up here since the VM subsystem insists that the
516		 * memmap entries are valid from the bank end aligned to
517		 * MAX_ORDER_NR_PAGES.
518		 */
519		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
520	}
521
522#ifdef CONFIG_SPARSEMEM
523	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
524		free_memmap(prev_bank_end,
525			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
526#endif
527}
528
 
 
 
 
 
 
 
 
529static void __init free_highpages(void)
530{
531#ifdef CONFIG_HIGHMEM
532	unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
533	struct memblock_region *mem, *res;
534
535	/* set highmem page free */
536	for_each_memblock(memory, mem) {
537		unsigned long start = memblock_region_memory_base_pfn(mem);
538		unsigned long end = memblock_region_memory_end_pfn(mem);
539
540		/* Ignore complete lowmem entries */
541		if (end <= max_low)
542			continue;
543
544		/* Truncate partial highmem entries */
545		if (start < max_low)
546			start = max_low;
547
548		/* Find and exclude any reserved regions */
549		for_each_memblock(reserved, res) {
550			unsigned long res_start, res_end;
551
552			res_start = memblock_region_reserved_base_pfn(res);
553			res_end = memblock_region_reserved_end_pfn(res);
554
555			if (res_end < start)
556				continue;
557			if (res_start < start)
558				res_start = start;
559			if (res_start > end)
560				res_start = end;
561			if (res_end > end)
562				res_end = end;
563			if (res_start != start)
564				totalhigh_pages += free_area(start, res_start,
565							     NULL);
566			start = res_end;
567			if (start == end)
568				break;
569		}
570
571		/* And now free anything which remains */
572		if (start < end)
573			totalhigh_pages += free_area(start, end, NULL);
574	}
575	totalram_pages += totalhigh_pages;
576#endif
577}
578
579/*
580 * mem_init() marks the free areas in the mem_map and tells us how much
581 * memory is free.  This is done after various parts of the system have
582 * claimed their memory after the kernel image.
583 */
584void __init mem_init(void)
585{
586	unsigned long reserved_pages, free_pages;
587	struct memblock_region *reg;
588	int i;
589#ifdef CONFIG_HAVE_TCM
590	/* These pointers are filled in on TCM detection */
591	extern u32 dtcm_end;
592	extern u32 itcm_end;
593#endif
594
595	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
596
597	/* this will put all unused low memory onto the freelists */
598	free_unused_memmap(&meminfo);
599
600	totalram_pages += free_all_bootmem();
601
602#ifdef CONFIG_SA1111
603	/* now that our DMA memory is actually so designated, we can free it */
604	totalram_pages += free_area(PHYS_PFN_OFFSET,
605				    __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
606#endif
607
608	free_highpages();
609
610	reserved_pages = free_pages = 0;
611
612	for_each_bank(i, &meminfo) {
613		struct membank *bank = &meminfo.bank[i];
614		unsigned int pfn1, pfn2;
615		struct page *page, *end;
616
617		pfn1 = bank_pfn_start(bank);
618		pfn2 = bank_pfn_end(bank);
619
620		page = pfn_to_page(pfn1);
621		end  = pfn_to_page(pfn2 - 1) + 1;
622
623		do {
624			if (PageReserved(page))
625				reserved_pages++;
626			else if (!page_count(page))
627				free_pages++;
628			page++;
629		} while (page < end);
630	}
631
632	/*
633	 * Since our memory may not be contiguous, calculate the
634	 * real number of pages we have in this system
635	 */
636	printk(KERN_INFO "Memory:");
637	num_physpages = 0;
638	for_each_memblock(memory, reg) {
639		unsigned long pages = memblock_region_memory_end_pfn(reg) -
640			memblock_region_memory_base_pfn(reg);
641		num_physpages += pages;
642		printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
643	}
644	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
645
646	printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n",
647		nr_free_pages() << (PAGE_SHIFT-10),
648		free_pages << (PAGE_SHIFT-10),
649		reserved_pages << (PAGE_SHIFT-10),
650		totalhigh_pages << (PAGE_SHIFT-10));
651
652#define MLK(b, t) b, t, ((t) - (b)) >> 10
653#define MLM(b, t) b, t, ((t) - (b)) >> 20
654#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
655
656	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
657			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
658#ifdef CONFIG_HAVE_TCM
659			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
660			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
661#endif
662			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
663#ifdef CONFIG_MMU
664			"    DMA     : 0x%08lx - 0x%08lx   (%4ld MB)\n"
665#endif
666			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
667			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
668#ifdef CONFIG_HIGHMEM
669			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
670#endif
 
671			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 
672			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
673			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
674			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
675			"       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
676
677			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
678				(PAGE_SIZE)),
679#ifdef CONFIG_HAVE_TCM
680			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
681			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
682#endif
683			MLK(FIXADDR_START, FIXADDR_TOP),
684#ifdef CONFIG_MMU
685			MLM(CONSISTENT_BASE, CONSISTENT_END),
686#endif
687			MLM(VMALLOC_START, VMALLOC_END),
688			MLM(PAGE_OFFSET, (unsigned long)high_memory),
689#ifdef CONFIG_HIGHMEM
690			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
691				(PAGE_SIZE)),
692#endif
 
693			MLM(MODULES_VADDR, MODULES_END),
 
694
695			MLK_ROUNDUP(_text, _etext),
696			MLK_ROUNDUP(__init_begin, __init_end),
697			MLK_ROUNDUP(_sdata, _edata),
698			MLK_ROUNDUP(__bss_start, __bss_stop));
699
700#undef MLK
701#undef MLM
702#undef MLK_ROUNDUP
703
704	/*
705	 * Check boundaries twice: Some fundamental inconsistencies can
706	 * be detected at build time already.
707	 */
708#ifdef CONFIG_MMU
709	BUILD_BUG_ON(VMALLOC_END			> CONSISTENT_BASE);
710	BUG_ON(VMALLOC_END				> CONSISTENT_BASE);
711
712	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
713	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
714#endif
715
716#ifdef CONFIG_HIGHMEM
717	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
718	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
719#endif
720
721	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
722		extern int sysctl_overcommit_memory;
723		/*
724		 * On a machine this small we won't get
725		 * anywhere without overcommit, so turn
726		 * it on by default.
727		 */
728		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
729	}
730}
731
732void free_initmem(void)
733{
734#ifdef CONFIG_HAVE_TCM
735	extern char __tcm_start, __tcm_end;
736
737	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
738	totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
739				    __phys_to_pfn(__pa(&__tcm_end)),
740				    "TCM link");
741#endif
742
743	poison_init_mem(__init_begin, __init_end - __init_begin);
744	if (!machine_is_integrator() && !machine_is_cintegrator())
745		totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
746					    __phys_to_pfn(__pa(__init_end)),
747					    "init");
748}
749
750#ifdef CONFIG_BLK_DEV_INITRD
751
752static int keep_initrd;
753
754void free_initrd_mem(unsigned long start, unsigned long end)
755{
756	if (!keep_initrd) {
757		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
758		totalram_pages += free_area(__phys_to_pfn(__pa(start)),
759					    __phys_to_pfn(__pa(end)),
760					    "initrd");
761	}
762}
763
764static int __init keepinitrd_setup(char *__unused)
765{
766	keep_initrd = 1;
767	return 1;
768}
769
770__setup("keepinitrd", keepinitrd_setup);
771#endif
v3.15
  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
 39static phys_addr_t phys_initrd_start __initdata = 0;
 40static unsigned long phys_initrd_size __initdata = 0;
 41
 42static 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}
 57early_param("initrd", early_initrd);
 58
 59static 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
 70static 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/*
 80 * This keeps memory configuration data used by a couple memory
 81 * initialization functions, as well as show_mem() for the skipping
 82 * of holes in the memory map.  It is populated by arm_add_memory().
 83 */
 84struct meminfo meminfo;
 85
 86void show_mem(unsigned int filter)
 87{
 88	int free = 0, total = 0, reserved = 0;
 89	int shared = 0, cached = 0, slab = 0, i;
 90	struct meminfo * mi = &meminfo;
 91
 92	printk("Mem-info:\n");
 93	show_free_areas(filter);
 94
 95	for_each_bank (i, mi) {
 96		struct membank *bank = &mi->bank[i];
 97		unsigned int pfn1, pfn2;
 98		struct page *page, *end;
 99
100		pfn1 = bank_pfn_start(bank);
101		pfn2 = bank_pfn_end(bank);
102
103		page = pfn_to_page(pfn1);
104		end  = pfn_to_page(pfn2 - 1) + 1;
105
106		do {
107			total++;
108			if (PageReserved(page))
109				reserved++;
110			else if (PageSwapCache(page))
111				cached++;
112			else if (PageSlab(page))
113				slab++;
114			else if (!page_count(page))
115				free++;
116			else
117				shared += page_count(page) - 1;
118			page++;
119		} while (page < end);
120	}
121
122	printk("%d pages of RAM\n", total);
123	printk("%d free pages\n", free);
124	printk("%d reserved pages\n", reserved);
125	printk("%d slab pages\n", slab);
126	printk("%d pages shared\n", shared);
127	printk("%d pages swap cached\n", cached);
128}
129
130static void __init find_limits(unsigned long *min, unsigned long *max_low,
131			       unsigned long *max_high)
132{
133	struct meminfo *mi = &meminfo;
134	int i;
135
136	/* This assumes the meminfo array is properly sorted */
137	*min = bank_pfn_start(&mi->bank[0]);
138	for_each_bank (i, mi)
139		if (mi->bank[i].highmem)
140				break;
141	*max_low = bank_pfn_end(&mi->bank[i - 1]);
142	*max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
143}
144
145#ifdef CONFIG_ZONE_DMA
146
147phys_addr_t arm_dma_zone_size __read_mostly;
148EXPORT_SYMBOL(arm_dma_zone_size);
149
150/*
151 * The DMA mask corresponding to the maximum bus address allocatable
152 * using GFP_DMA.  The default here places no restriction on DMA
153 * allocations.  This must be the smallest DMA mask in the system,
154 * so a successful GFP_DMA allocation will always satisfy this.
155 */
156phys_addr_t arm_dma_limit;
157unsigned long arm_dma_pfn_limit;
158
159static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
160	unsigned long dma_size)
161{
162	if (size[0] <= dma_size)
163		return;
164
165	size[ZONE_NORMAL] = size[0] - dma_size;
166	size[ZONE_DMA] = dma_size;
167	hole[ZONE_NORMAL] = hole[0];
168	hole[ZONE_DMA] = 0;
169}
170#endif
171
172void __init setup_dma_zone(const struct machine_desc *mdesc)
173{
174#ifdef CONFIG_ZONE_DMA
175	if (mdesc->dma_zone_size) {
176		arm_dma_zone_size = mdesc->dma_zone_size;
177		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
178	} else
179		arm_dma_limit = 0xffffffff;
180	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
181#endif
182}
183
184static 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
190	/*
191	 * initialise the zones.
192	 */
193	memset(zone_size, 0, sizeof(zone_size));
194
195	/*
196	 * The memory size has already been determined.  If we need
197	 * to do anything fancy with the allocation of this memory
198	 * to the zones, now is the time to do it.
199	 */
200	zone_size[0] = max_low - min;
201#ifdef CONFIG_HIGHMEM
202	zone_size[ZONE_HIGHMEM] = max_high - max_low;
203#endif
204
205	/*
206	 * Calculate the size of the holes.
207	 *  holes = node_size - sum(bank_sizes)
208	 */
209	memcpy(zhole_size, zone_size, sizeof(zhole_size));
210	for_each_memblock(memory, reg) {
211		unsigned long start = memblock_region_memory_base_pfn(reg);
212		unsigned long end = memblock_region_memory_end_pfn(reg);
213
214		if (start < max_low) {
215			unsigned long low_end = min(end, max_low);
216			zhole_size[0] -= low_end - start;
217		}
218#ifdef CONFIG_HIGHMEM
219		if (end > max_low) {
220			unsigned long high_start = max(start, max_low);
221			zhole_size[ZONE_HIGHMEM] -= end - high_start;
222		}
223#endif
224	}
225
226#ifdef CONFIG_ZONE_DMA
227	/*
228	 * Adjust the sizes according to any special requirements for
229	 * this machine type.
230	 */
231	if (arm_dma_zone_size)
232		arm_adjust_dma_zone(zone_size, zhole_size,
233			arm_dma_zone_size >> PAGE_SHIFT);
 
 
 
234#endif
235
236	free_area_init_node(0, zone_size, min, zhole_size);
237}
238
239#ifdef CONFIG_HAVE_ARCH_PFN_VALID
240int pfn_valid(unsigned long pfn)
241{
242	return memblock_is_memory(__pfn_to_phys(pfn));
243}
244EXPORT_SYMBOL(pfn_valid);
245#endif
246
247#ifndef CONFIG_SPARSEMEM
248static void __init arm_memory_present(void)
249{
250}
251#else
252static void __init arm_memory_present(void)
253{
254	struct memblock_region *reg;
255
256	for_each_memblock(memory, reg)
257		memory_present(0, memblock_region_memory_base_pfn(reg),
258			       memblock_region_memory_end_pfn(reg));
259}
260#endif
261
262static bool arm_memblock_steal_permitted = true;
263
264phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
265{
266	phys_addr_t phys;
267
268	BUG_ON(!arm_memblock_steal_permitted);
269
270	phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
271	memblock_free(phys, size);
272	memblock_remove(phys, size);
273
274	return phys;
275}
276
277void __init arm_memblock_init(struct meminfo *mi,
278	const struct machine_desc *mdesc)
279{
280	int i;
281
 
 
 
282	for (i = 0; i < mi->nr_banks; i++)
283		memblock_add(mi->bank[i].start, mi->bank[i].size);
284
285	/* Register the kernel text, kernel data and initrd with memblock. */
286#ifdef CONFIG_XIP_KERNEL
287	memblock_reserve(__pa(_sdata), _end - _sdata);
288#else
289	memblock_reserve(__pa(_stext), _end - _stext);
290#endif
291#ifdef CONFIG_BLK_DEV_INITRD
292	/* FDT scan will populate initrd_start */
293	if (initrd_start && !phys_initrd_size) {
294		phys_initrd_start = __virt_to_phys(initrd_start);
295		phys_initrd_size = initrd_end - initrd_start;
296	}
297	initrd_start = initrd_end = 0;
298	if (phys_initrd_size &&
299	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
300		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
301		       (u64)phys_initrd_start, phys_initrd_size);
302		phys_initrd_start = phys_initrd_size = 0;
303	}
304	if (phys_initrd_size &&
305	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
306		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
307		       (u64)phys_initrd_start, phys_initrd_size);
308		phys_initrd_start = phys_initrd_size = 0;
309	}
310	if (phys_initrd_size) {
311		memblock_reserve(phys_initrd_start, phys_initrd_size);
312
313		/* Now convert initrd to virtual addresses */
314		initrd_start = __phys_to_virt(phys_initrd_start);
315		initrd_end = initrd_start + phys_initrd_size;
316	}
317#endif
318
319	arm_mm_memblock_reserve();
320	arm_dt_memblock_reserve();
321
322	/* reserve any platform specific memblock areas */
323	if (mdesc->reserve)
324		mdesc->reserve();
325
326	early_init_fdt_scan_reserved_mem();
327
328	/*
329	 * reserve memory for DMA contigouos allocations,
330	 * must come from DMA area inside low memory
331	 */
332	dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
333
334	arm_memblock_steal_permitted = false;
335	memblock_dump_all();
336}
337
338void __init bootmem_init(void)
339{
340	unsigned long min, max_low, max_high;
341
342	memblock_allow_resize();
343	max_low = max_high = 0;
344
345	find_limits(&min, &max_low, &max_high);
346
 
 
347	/*
348	 * Sparsemem tries to allocate bootmem in memory_present(),
349	 * so must be done after the fixed reservations
350	 */
351	arm_memory_present();
352
353	/*
354	 * sparse_init() needs the bootmem allocator up and running.
355	 */
356	sparse_init();
357
358	/*
359	 * Now free the memory - free_area_init_node needs
360	 * the sparse mem_map arrays initialized by sparse_init()
361	 * for memmap_init_zone(), otherwise all PFNs are invalid.
362	 */
363	zone_sizes_init(min, max_low, max_high);
 
 
364
365	/*
366	 * This doesn't seem to be used by the Linux memory manager any
367	 * more, but is used by ll_rw_block.  If we can get rid of it, we
368	 * also get rid of some of the stuff above as well.
 
 
 
369	 */
370	min_low_pfn = min;
371	max_low_pfn = max_low;
372	max_pfn = max_high;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
373}
374
375/*
376 * Poison init memory with an undefined instruction (ARM) or a branch to an
377 * undefined instruction (Thumb).
378 */
379static inline void poison_init_mem(void *s, size_t count)
380{
381	u32 *p = (u32 *)s;
382	for (; count != 0; count -= 4)
383		*p++ = 0xe7fddef0;
384}
385
386static inline void
387free_memmap(unsigned long start_pfn, unsigned long end_pfn)
388{
389	struct page *start_pg, *end_pg;
390	phys_addr_t pg, pgend;
391
392	/*
393	 * Convert start_pfn/end_pfn to a struct page pointer.
394	 */
395	start_pg = pfn_to_page(start_pfn - 1) + 1;
396	end_pg = pfn_to_page(end_pfn - 1) + 1;
397
398	/*
399	 * Convert to physical addresses, and
400	 * round start upwards and end downwards.
401	 */
402	pg = PAGE_ALIGN(__pa(start_pg));
403	pgend = __pa(end_pg) & PAGE_MASK;
404
405	/*
406	 * If there are free pages between these,
407	 * free the section of the memmap array.
408	 */
409	if (pg < pgend)
410		memblock_free_early(pg, pgend - pg);
411}
412
413/*
414 * The mem_map array can get very big.  Free the unused area of the memory map.
415 */
416static void __init free_unused_memmap(struct meminfo *mi)
417{
418	unsigned long bank_start, prev_bank_end = 0;
419	unsigned int i;
420
421	/*
422	 * This relies on each bank being in address order.
423	 * The banks are sorted previously in bootmem_init().
424	 */
425	for_each_bank(i, mi) {
426		struct membank *bank = &mi->bank[i];
427
428		bank_start = bank_pfn_start(bank);
429
430#ifdef CONFIG_SPARSEMEM
431		/*
432		 * Take care not to free memmap entries that don't exist
433		 * due to SPARSEMEM sections which aren't present.
434		 */
435		bank_start = min(bank_start,
436				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
437#else
438		/*
439		 * Align down here since the VM subsystem insists that the
440		 * memmap entries are valid from the bank start aligned to
441		 * MAX_ORDER_NR_PAGES.
442		 */
443		bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
444#endif
445		/*
446		 * If we had a previous bank, and there is a space
447		 * between the current bank and the previous, free it.
448		 */
449		if (prev_bank_end && prev_bank_end < bank_start)
450			free_memmap(prev_bank_end, bank_start);
451
452		/*
453		 * Align up here since the VM subsystem insists that the
454		 * memmap entries are valid from the bank end aligned to
455		 * MAX_ORDER_NR_PAGES.
456		 */
457		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
458	}
459
460#ifdef CONFIG_SPARSEMEM
461	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
462		free_memmap(prev_bank_end,
463			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
464#endif
465}
466
467#ifdef CONFIG_HIGHMEM
468static inline void free_area_high(unsigned long pfn, unsigned long end)
469{
470	for (; pfn < end; pfn++)
471		free_highmem_page(pfn_to_page(pfn));
472}
473#endif
474
475static void __init free_highpages(void)
476{
477#ifdef CONFIG_HIGHMEM
478	unsigned long max_low = max_low_pfn;
479	struct memblock_region *mem, *res;
480
481	/* set highmem page free */
482	for_each_memblock(memory, mem) {
483		unsigned long start = memblock_region_memory_base_pfn(mem);
484		unsigned long end = memblock_region_memory_end_pfn(mem);
485
486		/* Ignore complete lowmem entries */
487		if (end <= max_low)
488			continue;
489
490		/* Truncate partial highmem entries */
491		if (start < max_low)
492			start = max_low;
493
494		/* Find and exclude any reserved regions */
495		for_each_memblock(reserved, res) {
496			unsigned long res_start, res_end;
497
498			res_start = memblock_region_reserved_base_pfn(res);
499			res_end = memblock_region_reserved_end_pfn(res);
500
501			if (res_end < start)
502				continue;
503			if (res_start < start)
504				res_start = start;
505			if (res_start > end)
506				res_start = end;
507			if (res_end > end)
508				res_end = end;
509			if (res_start != start)
510				free_area_high(start, res_start);
 
511			start = res_end;
512			if (start == end)
513				break;
514		}
515
516		/* And now free anything which remains */
517		if (start < end)
518			free_area_high(start, end);
519	}
 
520#endif
521}
522
523/*
524 * mem_init() marks the free areas in the mem_map and tells us how much
525 * memory is free.  This is done after various parts of the system have
526 * claimed their memory after the kernel image.
527 */
528void __init mem_init(void)
529{
 
 
 
530#ifdef CONFIG_HAVE_TCM
531	/* These pointers are filled in on TCM detection */
532	extern u32 dtcm_end;
533	extern u32 itcm_end;
534#endif
535
536	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
537
538	/* this will put all unused low memory onto the freelists */
539	free_unused_memmap(&meminfo);
540	free_all_bootmem();
 
541
542#ifdef CONFIG_SA1111
543	/* now that our DMA memory is actually so designated, we can free it */
544	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
 
545#endif
546
547	free_highpages();
548
549	mem_init_print_info(NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
550
551#define MLK(b, t) b, t, ((t) - (b)) >> 10
552#define MLM(b, t) b, t, ((t) - (b)) >> 20
553#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
554
555	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
556			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
557#ifdef CONFIG_HAVE_TCM
558			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
559			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
560#endif
561			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 
 
 
562			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
563			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
564#ifdef CONFIG_HIGHMEM
565			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
566#endif
567#ifdef CONFIG_MODULES
568			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
569#endif
570			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
571			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
572			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
573			"       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
574
575			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
576				(PAGE_SIZE)),
577#ifdef CONFIG_HAVE_TCM
578			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
579			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
580#endif
581			MLK(FIXADDR_START, FIXADDR_TOP),
 
 
 
582			MLM(VMALLOC_START, VMALLOC_END),
583			MLM(PAGE_OFFSET, (unsigned long)high_memory),
584#ifdef CONFIG_HIGHMEM
585			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
586				(PAGE_SIZE)),
587#endif
588#ifdef CONFIG_MODULES
589			MLM(MODULES_VADDR, MODULES_END),
590#endif
591
592			MLK_ROUNDUP(_text, _etext),
593			MLK_ROUNDUP(__init_begin, __init_end),
594			MLK_ROUNDUP(_sdata, _edata),
595			MLK_ROUNDUP(__bss_start, __bss_stop));
596
597#undef MLK
598#undef MLM
599#undef MLK_ROUNDUP
600
601	/*
602	 * Check boundaries twice: Some fundamental inconsistencies can
603	 * be detected at build time already.
604	 */
605#ifdef CONFIG_MMU
 
 
 
606	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
607	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
608#endif
609
610#ifdef CONFIG_HIGHMEM
611	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
612	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
613#endif
614
615	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
616		extern int sysctl_overcommit_memory;
617		/*
618		 * On a machine this small we won't get
619		 * anywhere without overcommit, so turn
620		 * it on by default.
621		 */
622		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
623	}
624}
625
626void free_initmem(void)
627{
628#ifdef CONFIG_HAVE_TCM
629	extern char __tcm_start, __tcm_end;
630
631	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
632	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
 
 
633#endif
634
635	poison_init_mem(__init_begin, __init_end - __init_begin);
636	if (!machine_is_integrator() && !machine_is_cintegrator())
637		free_initmem_default(-1);
 
 
638}
639
640#ifdef CONFIG_BLK_DEV_INITRD
641
642static int keep_initrd;
643
644void free_initrd_mem(unsigned long start, unsigned long end)
645{
646	if (!keep_initrd) {
647		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
648		free_reserved_area((void *)start, (void *)end, -1, "initrd");
 
 
649	}
650}
651
652static int __init keepinitrd_setup(char *__unused)
653{
654	keep_initrd = 1;
655	return 1;
656}
657
658__setup("keepinitrd", keepinitrd_setup);
659#endif