xref: /openbmc/linux/arch/arm/mm/init.c (revision 7bf02ea22c6cdd09e2d3f1d3c3fe366b834ae9af)
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/highmem.h>
19 #include <linux/gfp.h>
20 #include <linux/memblock.h>
21 #include <linux/sort.h>
22 
23 #include <asm/mach-types.h>
24 #include <asm/sections.h>
25 #include <asm/setup.h>
26 #include <asm/sizes.h>
27 #include <asm/tlb.h>
28 #include <asm/fixmap.h>
29 
30 #include <asm/mach/arch.h>
31 #include <asm/mach/map.h>
32 
33 #include "mm.h"
34 
35 static unsigned long phys_initrd_start __initdata = 0;
36 static unsigned long phys_initrd_size __initdata = 0;
37 
38 static int __init early_initrd(char *p)
39 {
40 	unsigned long start, size;
41 	char *endp;
42 
43 	start = memparse(p, &endp);
44 	if (*endp == ',') {
45 		size = memparse(endp + 1, NULL);
46 
47 		phys_initrd_start = start;
48 		phys_initrd_size = size;
49 	}
50 	return 0;
51 }
52 early_param("initrd", early_initrd);
53 
54 static int __init parse_tag_initrd(const struct tag *tag)
55 {
56 	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
57 		"please update your bootloader.\n");
58 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
59 	phys_initrd_size = tag->u.initrd.size;
60 	return 0;
61 }
62 
63 __tagtable(ATAG_INITRD, parse_tag_initrd);
64 
65 static int __init parse_tag_initrd2(const struct tag *tag)
66 {
67 	phys_initrd_start = tag->u.initrd.start;
68 	phys_initrd_size = tag->u.initrd.size;
69 	return 0;
70 }
71 
72 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
73 
74 /*
75  * This keeps memory configuration data used by a couple memory
76  * initialization functions, as well as show_mem() for the skipping
77  * of holes in the memory map.  It is populated by arm_add_memory().
78  */
79 struct meminfo meminfo;
80 
81 void show_mem(unsigned int filter)
82 {
83 	int free = 0, total = 0, reserved = 0;
84 	int shared = 0, cached = 0, slab = 0, i;
85 	struct meminfo * mi = &meminfo;
86 
87 	printk("Mem-info:\n");
88 	show_free_areas(filter);
89 
90 	for_each_bank (i, mi) {
91 		struct membank *bank = &mi->bank[i];
92 		unsigned int pfn1, pfn2;
93 		struct page *page, *end;
94 
95 		pfn1 = bank_pfn_start(bank);
96 		pfn2 = bank_pfn_end(bank);
97 
98 		page = pfn_to_page(pfn1);
99 		end  = pfn_to_page(pfn2 - 1) + 1;
100 
101 		do {
102 			total++;
103 			if (PageReserved(page))
104 				reserved++;
105 			else if (PageSwapCache(page))
106 				cached++;
107 			else if (PageSlab(page))
108 				slab++;
109 			else if (!page_count(page))
110 				free++;
111 			else
112 				shared += page_count(page) - 1;
113 			page++;
114 		} while (page < end);
115 	}
116 
117 	printk("%d pages of RAM\n", total);
118 	printk("%d free pages\n", free);
119 	printk("%d reserved pages\n", reserved);
120 	printk("%d slab pages\n", slab);
121 	printk("%d pages shared\n", shared);
122 	printk("%d pages swap cached\n", cached);
123 }
124 
125 static void __init find_limits(unsigned long *min, unsigned long *max_low,
126 	unsigned long *max_high)
127 {
128 	struct meminfo *mi = &meminfo;
129 	int i;
130 
131 	*min = -1UL;
132 	*max_low = *max_high = 0;
133 
134 	for_each_bank (i, mi) {
135 		struct membank *bank = &mi->bank[i];
136 		unsigned long start, end;
137 
138 		start = bank_pfn_start(bank);
139 		end = bank_pfn_end(bank);
140 
141 		if (*min > start)
142 			*min = start;
143 		if (*max_high < end)
144 			*max_high = end;
145 		if (bank->highmem)
146 			continue;
147 		if (*max_low < end)
148 			*max_low = end;
149 	}
150 }
151 
152 static void __init arm_bootmem_init(unsigned long start_pfn,
153 	unsigned long end_pfn)
154 {
155 	struct memblock_region *reg;
156 	unsigned int boot_pages;
157 	phys_addr_t bitmap;
158 	pg_data_t *pgdat;
159 
160 	/*
161 	 * Allocate the bootmem bitmap page.  This must be in a region
162 	 * of memory which has already been mapped.
163 	 */
164 	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
165 	bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
166 				__pfn_to_phys(end_pfn));
167 
168 	/*
169 	 * Initialise the bootmem allocator, handing the
170 	 * memory banks over to bootmem.
171 	 */
172 	node_set_online(0);
173 	pgdat = NODE_DATA(0);
174 	init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
175 
176 	/* Free the lowmem regions from memblock into bootmem. */
177 	for_each_memblock(memory, reg) {
178 		unsigned long start = memblock_region_memory_base_pfn(reg);
179 		unsigned long end = memblock_region_memory_end_pfn(reg);
180 
181 		if (end >= end_pfn)
182 			end = end_pfn;
183 		if (start >= end)
184 			break;
185 
186 		free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
187 	}
188 
189 	/* Reserve the lowmem memblock reserved regions in bootmem. */
190 	for_each_memblock(reserved, reg) {
191 		unsigned long start = memblock_region_reserved_base_pfn(reg);
192 		unsigned long end = memblock_region_reserved_end_pfn(reg);
193 
194 		if (end >= end_pfn)
195 			end = end_pfn;
196 		if (start >= end)
197 			break;
198 
199 		reserve_bootmem(__pfn_to_phys(start),
200 			        (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
201 	}
202 }
203 
204 #ifdef CONFIG_ZONE_DMA
205 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
206 	unsigned long dma_size)
207 {
208 	if (size[0] <= dma_size)
209 		return;
210 
211 	size[ZONE_NORMAL] = size[0] - dma_size;
212 	size[ZONE_DMA] = dma_size;
213 	hole[ZONE_NORMAL] = hole[0];
214 	hole[ZONE_DMA] = 0;
215 }
216 #endif
217 
218 static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
219 	unsigned long max_high)
220 {
221 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
222 	struct memblock_region *reg;
223 
224 	/*
225 	 * initialise the zones.
226 	 */
227 	memset(zone_size, 0, sizeof(zone_size));
228 
229 	/*
230 	 * The memory size has already been determined.  If we need
231 	 * to do anything fancy with the allocation of this memory
232 	 * to the zones, now is the time to do it.
233 	 */
234 	zone_size[0] = max_low - min;
235 #ifdef CONFIG_HIGHMEM
236 	zone_size[ZONE_HIGHMEM] = max_high - max_low;
237 #endif
238 
239 	/*
240 	 * Calculate the size of the holes.
241 	 *  holes = node_size - sum(bank_sizes)
242 	 */
243 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
244 	for_each_memblock(memory, reg) {
245 		unsigned long start = memblock_region_memory_base_pfn(reg);
246 		unsigned long end = memblock_region_memory_end_pfn(reg);
247 
248 		if (start < max_low) {
249 			unsigned long low_end = min(end, max_low);
250 			zhole_size[0] -= low_end - start;
251 		}
252 #ifdef CONFIG_HIGHMEM
253 		if (end > max_low) {
254 			unsigned long high_start = max(start, max_low);
255 			zhole_size[ZONE_HIGHMEM] -= end - high_start;
256 		}
257 #endif
258 	}
259 
260 #ifdef ARM_DMA_ZONE_SIZE
261 #ifndef CONFIG_ZONE_DMA
262 #error ARM_DMA_ZONE_SIZE set but no DMA zone to limit allocations
263 #endif
264 
265 	/*
266 	 * Adjust the sizes according to any special requirements for
267 	 * this machine type.
268 	 */
269 	arm_adjust_dma_zone(zone_size, zhole_size,
270 		ARM_DMA_ZONE_SIZE >> PAGE_SHIFT);
271 #endif
272 
273 	free_area_init_node(0, zone_size, min, zhole_size);
274 }
275 
276 #ifndef CONFIG_SPARSEMEM
277 int pfn_valid(unsigned long pfn)
278 {
279 	return memblock_is_memory(pfn << PAGE_SHIFT);
280 }
281 EXPORT_SYMBOL(pfn_valid);
282 
283 static void arm_memory_present(void)
284 {
285 }
286 #else
287 static void arm_memory_present(void)
288 {
289 	struct memblock_region *reg;
290 
291 	for_each_memblock(memory, reg)
292 		memory_present(0, memblock_region_memory_base_pfn(reg),
293 			       memblock_region_memory_end_pfn(reg));
294 }
295 #endif
296 
297 static int __init meminfo_cmp(const void *_a, const void *_b)
298 {
299 	const struct membank *a = _a, *b = _b;
300 	long cmp = bank_pfn_start(a) - bank_pfn_start(b);
301 	return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
302 }
303 
304 void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
305 {
306 	int i;
307 
308 	sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
309 
310 	memblock_init();
311 	for (i = 0; i < mi->nr_banks; i++)
312 		memblock_add(mi->bank[i].start, mi->bank[i].size);
313 
314 	/* Register the kernel text, kernel data and initrd with memblock. */
315 #ifdef CONFIG_XIP_KERNEL
316 	memblock_reserve(__pa(_sdata), _end - _sdata);
317 #else
318 	memblock_reserve(__pa(_stext), _end - _stext);
319 #endif
320 #ifdef CONFIG_BLK_DEV_INITRD
321 	if (phys_initrd_size &&
322 	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
323 		pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n",
324 		       phys_initrd_start, phys_initrd_size);
325 		phys_initrd_start = phys_initrd_size = 0;
326 	}
327 	if (phys_initrd_size) {
328 		memblock_reserve(phys_initrd_start, phys_initrd_size);
329 
330 		/* Now convert initrd to virtual addresses */
331 		initrd_start = __phys_to_virt(phys_initrd_start);
332 		initrd_end = initrd_start + phys_initrd_size;
333 	}
334 #endif
335 
336 	arm_mm_memblock_reserve();
337 
338 	/* reserve any platform specific memblock areas */
339 	if (mdesc->reserve)
340 		mdesc->reserve();
341 
342 	memblock_analyze();
343 	memblock_dump_all();
344 }
345 
346 void __init bootmem_init(void)
347 {
348 	unsigned long min, max_low, max_high;
349 
350 	max_low = max_high = 0;
351 
352 	find_limits(&min, &max_low, &max_high);
353 
354 	arm_bootmem_init(min, max_low);
355 
356 	/*
357 	 * Sparsemem tries to allocate bootmem in memory_present(),
358 	 * so must be done after the fixed reservations
359 	 */
360 	arm_memory_present();
361 
362 	/*
363 	 * sparse_init() needs the bootmem allocator up and running.
364 	 */
365 	sparse_init();
366 
367 	/*
368 	 * Now free the memory - free_area_init_node needs
369 	 * the sparse mem_map arrays initialized by sparse_init()
370 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
371 	 */
372 	arm_bootmem_free(min, max_low, max_high);
373 
374 	high_memory = __va(((phys_addr_t)max_low << PAGE_SHIFT) - 1) + 1;
375 
376 	/*
377 	 * This doesn't seem to be used by the Linux memory manager any
378 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
379 	 * also get rid of some of the stuff above as well.
380 	 *
381 	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
382 	 * the system, not the maximum PFN.
383 	 */
384 	max_low_pfn = max_low - PHYS_PFN_OFFSET;
385 	max_pfn = max_high - PHYS_PFN_OFFSET;
386 }
387 
388 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
389 {
390 	unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
391 
392 	for (; pfn < end; pfn++) {
393 		struct page *page = pfn_to_page(pfn);
394 		ClearPageReserved(page);
395 		init_page_count(page);
396 		__free_page(page);
397 		pages++;
398 	}
399 
400 	if (size && s)
401 		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
402 
403 	return pages;
404 }
405 
406 static inline void
407 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
408 {
409 	struct page *start_pg, *end_pg;
410 	unsigned long pg, pgend;
411 
412 	/*
413 	 * Convert start_pfn/end_pfn to a struct page pointer.
414 	 */
415 	start_pg = pfn_to_page(start_pfn - 1) + 1;
416 	end_pg = pfn_to_page(end_pfn - 1) + 1;
417 
418 	/*
419 	 * Convert to physical addresses, and
420 	 * round start upwards and end downwards.
421 	 */
422 	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
423 	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
424 
425 	/*
426 	 * If there are free pages between these,
427 	 * free the section of the memmap array.
428 	 */
429 	if (pg < pgend)
430 		free_bootmem(pg, pgend - pg);
431 }
432 
433 /*
434  * The mem_map array can get very big.  Free the unused area of the memory map.
435  */
436 static void __init free_unused_memmap(struct meminfo *mi)
437 {
438 	unsigned long bank_start, prev_bank_end = 0;
439 	unsigned int i;
440 
441 	/*
442 	 * This relies on each bank being in address order.
443 	 * The banks are sorted previously in bootmem_init().
444 	 */
445 	for_each_bank(i, mi) {
446 		struct membank *bank = &mi->bank[i];
447 
448 		bank_start = bank_pfn_start(bank);
449 
450 #ifdef CONFIG_SPARSEMEM
451 		/*
452 		 * Take care not to free memmap entries that don't exist
453 		 * due to SPARSEMEM sections which aren't present.
454 		 */
455 		bank_start = min(bank_start,
456 				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
457 #endif
458 		/*
459 		 * If we had a previous bank, and there is a space
460 		 * between the current bank and the previous, free it.
461 		 */
462 		if (prev_bank_end && prev_bank_end < bank_start)
463 			free_memmap(prev_bank_end, bank_start);
464 
465 		/*
466 		 * Align up here since the VM subsystem insists that the
467 		 * memmap entries are valid from the bank end aligned to
468 		 * MAX_ORDER_NR_PAGES.
469 		 */
470 		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
471 	}
472 
473 #ifdef CONFIG_SPARSEMEM
474 	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
475 		free_memmap(prev_bank_end,
476 			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
477 #endif
478 }
479 
480 static void __init free_highpages(void)
481 {
482 #ifdef CONFIG_HIGHMEM
483 	unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
484 	struct memblock_region *mem, *res;
485 
486 	/* set highmem page free */
487 	for_each_memblock(memory, mem) {
488 		unsigned long start = memblock_region_memory_base_pfn(mem);
489 		unsigned long end = memblock_region_memory_end_pfn(mem);
490 
491 		/* Ignore complete lowmem entries */
492 		if (end <= max_low)
493 			continue;
494 
495 		/* Truncate partial highmem entries */
496 		if (start < max_low)
497 			start = max_low;
498 
499 		/* Find and exclude any reserved regions */
500 		for_each_memblock(reserved, res) {
501 			unsigned long res_start, res_end;
502 
503 			res_start = memblock_region_reserved_base_pfn(res);
504 			res_end = memblock_region_reserved_end_pfn(res);
505 
506 			if (res_end < start)
507 				continue;
508 			if (res_start < start)
509 				res_start = start;
510 			if (res_start > end)
511 				res_start = end;
512 			if (res_end > end)
513 				res_end = end;
514 			if (res_start != start)
515 				totalhigh_pages += free_area(start, res_start,
516 							     NULL);
517 			start = res_end;
518 			if (start == end)
519 				break;
520 		}
521 
522 		/* And now free anything which remains */
523 		if (start < end)
524 			totalhigh_pages += free_area(start, end, NULL);
525 	}
526 	totalram_pages += totalhigh_pages;
527 #endif
528 }
529 
530 /*
531  * mem_init() marks the free areas in the mem_map and tells us how much
532  * memory is free.  This is done after various parts of the system have
533  * claimed their memory after the kernel image.
534  */
535 void __init mem_init(void)
536 {
537 	unsigned long reserved_pages, free_pages;
538 	struct memblock_region *reg;
539 	int i;
540 #ifdef CONFIG_HAVE_TCM
541 	/* These pointers are filled in on TCM detection */
542 	extern u32 dtcm_end;
543 	extern u32 itcm_end;
544 #endif
545 
546 	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
547 
548 	/* this will put all unused low memory onto the freelists */
549 	free_unused_memmap(&meminfo);
550 
551 	totalram_pages += free_all_bootmem();
552 
553 #ifdef CONFIG_SA1111
554 	/* now that our DMA memory is actually so designated, we can free it */
555 	totalram_pages += free_area(PHYS_PFN_OFFSET,
556 				    __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
557 #endif
558 
559 	free_highpages();
560 
561 	reserved_pages = free_pages = 0;
562 
563 	for_each_bank(i, &meminfo) {
564 		struct membank *bank = &meminfo.bank[i];
565 		unsigned int pfn1, pfn2;
566 		struct page *page, *end;
567 
568 		pfn1 = bank_pfn_start(bank);
569 		pfn2 = bank_pfn_end(bank);
570 
571 		page = pfn_to_page(pfn1);
572 		end  = pfn_to_page(pfn2 - 1) + 1;
573 
574 		do {
575 			if (PageReserved(page))
576 				reserved_pages++;
577 			else if (!page_count(page))
578 				free_pages++;
579 			page++;
580 		} while (page < end);
581 	}
582 
583 	/*
584 	 * Since our memory may not be contiguous, calculate the
585 	 * real number of pages we have in this system
586 	 */
587 	printk(KERN_INFO "Memory:");
588 	num_physpages = 0;
589 	for_each_memblock(memory, reg) {
590 		unsigned long pages = memblock_region_memory_end_pfn(reg) -
591 			memblock_region_memory_base_pfn(reg);
592 		num_physpages += pages;
593 		printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
594 	}
595 	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
596 
597 	printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n",
598 		nr_free_pages() << (PAGE_SHIFT-10),
599 		free_pages << (PAGE_SHIFT-10),
600 		reserved_pages << (PAGE_SHIFT-10),
601 		totalhigh_pages << (PAGE_SHIFT-10));
602 
603 #define MLK(b, t) b, t, ((t) - (b)) >> 10
604 #define MLM(b, t) b, t, ((t) - (b)) >> 20
605 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
606 
607 	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
608 			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
609 #ifdef CONFIG_HAVE_TCM
610 			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
611 			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
612 #endif
613 			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
614 #ifdef CONFIG_MMU
615 			"    DMA     : 0x%08lx - 0x%08lx   (%4ld MB)\n"
616 #endif
617 			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
618 			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
619 #ifdef CONFIG_HIGHMEM
620 			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
621 #endif
622 			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
623 			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
624 			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
625 			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n",
626 
627 			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
628 				(PAGE_SIZE)),
629 #ifdef CONFIG_HAVE_TCM
630 			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
631 			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
632 #endif
633 			MLK(FIXADDR_START, FIXADDR_TOP),
634 #ifdef CONFIG_MMU
635 			MLM(CONSISTENT_BASE, CONSISTENT_END),
636 #endif
637 			MLM(VMALLOC_START, VMALLOC_END),
638 			MLM(PAGE_OFFSET, (unsigned long)high_memory),
639 #ifdef CONFIG_HIGHMEM
640 			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
641 				(PAGE_SIZE)),
642 #endif
643 			MLM(MODULES_VADDR, MODULES_END),
644 
645 			MLK_ROUNDUP(__init_begin, __init_end),
646 			MLK_ROUNDUP(_text, _etext),
647 			MLK_ROUNDUP(_sdata, _edata));
648 
649 #undef MLK
650 #undef MLM
651 #undef MLK_ROUNDUP
652 
653 	/*
654 	 * Check boundaries twice: Some fundamental inconsistencies can
655 	 * be detected at build time already.
656 	 */
657 #ifdef CONFIG_MMU
658 	BUILD_BUG_ON(VMALLOC_END			> CONSISTENT_BASE);
659 	BUG_ON(VMALLOC_END				> CONSISTENT_BASE);
660 
661 	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
662 	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
663 #endif
664 
665 #ifdef CONFIG_HIGHMEM
666 	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
667 	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
668 #endif
669 
670 	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
671 		extern int sysctl_overcommit_memory;
672 		/*
673 		 * On a machine this small we won't get
674 		 * anywhere without overcommit, so turn
675 		 * it on by default.
676 		 */
677 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
678 	}
679 }
680 
681 void free_initmem(void)
682 {
683 #ifdef CONFIG_HAVE_TCM
684 	extern char __tcm_start, __tcm_end;
685 
686 	totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
687 				    __phys_to_pfn(__pa(&__tcm_end)),
688 				    "TCM link");
689 #endif
690 
691 	if (!machine_is_integrator() && !machine_is_cintegrator())
692 		totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
693 					    __phys_to_pfn(__pa(__init_end)),
694 					    "init");
695 }
696 
697 #ifdef CONFIG_BLK_DEV_INITRD
698 
699 static int keep_initrd;
700 
701 void free_initrd_mem(unsigned long start, unsigned long end)
702 {
703 	if (!keep_initrd)
704 		totalram_pages += free_area(__phys_to_pfn(__pa(start)),
705 					    __phys_to_pfn(__pa(end)),
706 					    "initrd");
707 }
708 
709 static int __init keepinitrd_setup(char *__unused)
710 {
711 	keep_initrd = 1;
712 	return 1;
713 }
714 
715 __setup("keepinitrd", keepinitrd_setup);
716 #endif
717