xref: /openbmc/linux/arch/arm/mm/init.c (revision fd589a8f)
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/sort.h>
19 #include <linux/highmem.h>
20 
21 #include <asm/mach-types.h>
22 #include <asm/sections.h>
23 #include <asm/setup.h>
24 #include <asm/sizes.h>
25 #include <asm/tlb.h>
26 
27 #include <asm/mach/arch.h>
28 #include <asm/mach/map.h>
29 
30 #include "mm.h"
31 
32 static unsigned long phys_initrd_start __initdata = 0;
33 static unsigned long phys_initrd_size __initdata = 0;
34 
35 static void __init early_initrd(char **p)
36 {
37 	unsigned long start, size;
38 
39 	start = memparse(*p, p);
40 	if (**p == ',') {
41 		size = memparse((*p) + 1, p);
42 
43 		phys_initrd_start = start;
44 		phys_initrd_size = size;
45 	}
46 }
47 __early_param("initrd=", early_initrd);
48 
49 static int __init parse_tag_initrd(const struct tag *tag)
50 {
51 	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
52 		"please update your bootloader.\n");
53 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
54 	phys_initrd_size = tag->u.initrd.size;
55 	return 0;
56 }
57 
58 __tagtable(ATAG_INITRD, parse_tag_initrd);
59 
60 static int __init parse_tag_initrd2(const struct tag *tag)
61 {
62 	phys_initrd_start = tag->u.initrd.start;
63 	phys_initrd_size = tag->u.initrd.size;
64 	return 0;
65 }
66 
67 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
68 
69 /*
70  * This keeps memory configuration data used by a couple memory
71  * initialization functions, as well as show_mem() for the skipping
72  * of holes in the memory map.  It is populated by arm_add_memory().
73  */
74 struct meminfo meminfo;
75 
76 void show_mem(void)
77 {
78 	int free = 0, total = 0, reserved = 0;
79 	int shared = 0, cached = 0, slab = 0, node, i;
80 	struct meminfo * mi = &meminfo;
81 
82 	printk("Mem-info:\n");
83 	show_free_areas();
84 	for_each_online_node(node) {
85 		pg_data_t *n = NODE_DATA(node);
86 		struct page *map = pgdat_page_nr(n, 0) - n->node_start_pfn;
87 
88 		for_each_nodebank (i,mi,node) {
89 			struct membank *bank = &mi->bank[i];
90 			unsigned int pfn1, pfn2;
91 			struct page *page, *end;
92 
93 			pfn1 = bank_pfn_start(bank);
94 			pfn2 = bank_pfn_end(bank);
95 
96 			page = map + pfn1;
97 			end  = map + pfn2;
98 
99 			do {
100 				total++;
101 				if (PageReserved(page))
102 					reserved++;
103 				else if (PageSwapCache(page))
104 					cached++;
105 				else if (PageSlab(page))
106 					slab++;
107 				else if (!page_count(page))
108 					free++;
109 				else
110 					shared += page_count(page) - 1;
111 				page++;
112 			} while (page < end);
113 		}
114 	}
115 
116 	printk("%d pages of RAM\n", total);
117 	printk("%d free pages\n", free);
118 	printk("%d reserved pages\n", reserved);
119 	printk("%d slab pages\n", slab);
120 	printk("%d pages shared\n", shared);
121 	printk("%d pages swap cached\n", cached);
122 }
123 
124 static void __init find_node_limits(int node, struct meminfo *mi,
125 	unsigned long *min, unsigned long *max_low, unsigned long *max_high)
126 {
127 	int i;
128 
129 	*min = -1UL;
130 	*max_low = *max_high = 0;
131 
132 	for_each_nodebank(i, mi, node) {
133 		struct membank *bank = &mi->bank[i];
134 		unsigned long start, end;
135 
136 		start = bank_pfn_start(bank);
137 		end = bank_pfn_end(bank);
138 
139 		if (*min > start)
140 			*min = start;
141 		if (*max_high < end)
142 			*max_high = end;
143 		if (bank->highmem)
144 			continue;
145 		if (*max_low < end)
146 			*max_low = end;
147 	}
148 }
149 
150 /*
151  * FIXME: We really want to avoid allocating the bootmap bitmap
152  * over the top of the initrd.  Hopefully, this is located towards
153  * the start of a bank, so if we allocate the bootmap bitmap at
154  * the end, we won't clash.
155  */
156 static unsigned int __init
157 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
158 {
159 	unsigned int start_pfn, i, bootmap_pfn;
160 
161 	start_pfn   = PAGE_ALIGN(__pa(_end)) >> PAGE_SHIFT;
162 	bootmap_pfn = 0;
163 
164 	for_each_nodebank(i, mi, node) {
165 		struct membank *bank = &mi->bank[i];
166 		unsigned int start, end;
167 
168 		start = bank_pfn_start(bank);
169 		end   = bank_pfn_end(bank);
170 
171 		if (end < start_pfn)
172 			continue;
173 
174 		if (start < start_pfn)
175 			start = start_pfn;
176 
177 		if (end <= start)
178 			continue;
179 
180 		if (end - start >= bootmap_pages) {
181 			bootmap_pfn = start;
182 			break;
183 		}
184 	}
185 
186 	if (bootmap_pfn == 0)
187 		BUG();
188 
189 	return bootmap_pfn;
190 }
191 
192 static int __init check_initrd(struct meminfo *mi)
193 {
194 	int initrd_node = -2;
195 #ifdef CONFIG_BLK_DEV_INITRD
196 	unsigned long end = phys_initrd_start + phys_initrd_size;
197 
198 	/*
199 	 * Make sure that the initrd is within a valid area of
200 	 * memory.
201 	 */
202 	if (phys_initrd_size) {
203 		unsigned int i;
204 
205 		initrd_node = -1;
206 
207 		for (i = 0; i < mi->nr_banks; i++) {
208 			struct membank *bank = &mi->bank[i];
209 			if (bank_phys_start(bank) <= phys_initrd_start &&
210 			    end <= bank_phys_end(bank))
211 				initrd_node = bank->node;
212 		}
213 	}
214 
215 	if (initrd_node == -1) {
216 		printk(KERN_ERR "INITRD: 0x%08lx+0x%08lx extends beyond "
217 		       "physical memory - disabling initrd\n",
218 		       phys_initrd_start, phys_initrd_size);
219 		phys_initrd_start = phys_initrd_size = 0;
220 	}
221 #endif
222 
223 	return initrd_node;
224 }
225 
226 static inline void map_memory_bank(struct membank *bank)
227 {
228 #ifdef CONFIG_MMU
229 	struct map_desc map;
230 
231 	map.pfn = bank_pfn_start(bank);
232 	map.virtual = __phys_to_virt(bank_phys_start(bank));
233 	map.length = bank_phys_size(bank);
234 	map.type = MT_MEMORY;
235 
236 	create_mapping(&map);
237 #endif
238 }
239 
240 static void __init bootmem_init_node(int node, struct meminfo *mi,
241 	unsigned long start_pfn, unsigned long end_pfn)
242 {
243 	unsigned long boot_pfn;
244 	unsigned int boot_pages;
245 	pg_data_t *pgdat;
246 	int i;
247 
248 	/*
249 	 * Map the memory banks for this node.
250 	 */
251 	for_each_nodebank(i, mi, node) {
252 		struct membank *bank = &mi->bank[i];
253 
254 		if (!bank->highmem)
255 			map_memory_bank(bank);
256 	}
257 
258 	/*
259 	 * Allocate the bootmem bitmap page.
260 	 */
261 	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
262 	boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
263 
264 	/*
265 	 * Initialise the bootmem allocator for this node, handing the
266 	 * memory banks over to bootmem.
267 	 */
268 	node_set_online(node);
269 	pgdat = NODE_DATA(node);
270 	init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
271 
272 	for_each_nodebank(i, mi, node) {
273 		struct membank *bank = &mi->bank[i];
274 		if (!bank->highmem)
275 			free_bootmem_node(pgdat, bank_phys_start(bank), bank_phys_size(bank));
276 		memory_present(node, bank_pfn_start(bank), bank_pfn_end(bank));
277 	}
278 
279 	/*
280 	 * Reserve the bootmem bitmap for this node.
281 	 */
282 	reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
283 			     boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
284 }
285 
286 static void __init bootmem_reserve_initrd(int node)
287 {
288 #ifdef CONFIG_BLK_DEV_INITRD
289 	pg_data_t *pgdat = NODE_DATA(node);
290 	int res;
291 
292 	res = reserve_bootmem_node(pgdat, phys_initrd_start,
293 			     phys_initrd_size, BOOTMEM_EXCLUSIVE);
294 
295 	if (res == 0) {
296 		initrd_start = __phys_to_virt(phys_initrd_start);
297 		initrd_end = initrd_start + phys_initrd_size;
298 	} else {
299 		printk(KERN_ERR
300 			"INITRD: 0x%08lx+0x%08lx overlaps in-use "
301 			"memory region - disabling initrd\n",
302 			phys_initrd_start, phys_initrd_size);
303 	}
304 #endif
305 }
306 
307 static void __init bootmem_free_node(int node, struct meminfo *mi)
308 {
309 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
310 	unsigned long min, max_low, max_high;
311 	int i;
312 
313 	find_node_limits(node, mi, &min, &max_low, &max_high);
314 
315 	/*
316 	 * initialise the zones within this node.
317 	 */
318 	memset(zone_size, 0, sizeof(zone_size));
319 
320 	/*
321 	 * The size of this node has already been determined.  If we need
322 	 * to do anything fancy with the allocation of this memory to the
323 	 * zones, now is the time to do it.
324 	 */
325 	zone_size[0] = max_low - min;
326 #ifdef CONFIG_HIGHMEM
327 	zone_size[ZONE_HIGHMEM] = max_high - max_low;
328 #endif
329 
330 	/*
331 	 * For each bank in this node, calculate the size of the holes.
332 	 *  holes = node_size - sum(bank_sizes_in_node)
333 	 */
334 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
335 	for_each_nodebank(i, mi, node) {
336 		int idx = 0;
337 #ifdef CONFIG_HIGHMEM
338 		if (mi->bank[i].highmem)
339 			idx = ZONE_HIGHMEM;
340 #endif
341 		zhole_size[idx] -= bank_pfn_size(&mi->bank[i]);
342 	}
343 
344 	/*
345 	 * Adjust the sizes according to any special requirements for
346 	 * this machine type.
347 	 */
348 	arch_adjust_zones(node, zone_size, zhole_size);
349 
350 	free_area_init_node(node, zone_size, min, zhole_size);
351 }
352 
353 #ifndef CONFIG_SPARSEMEM
354 int pfn_valid(unsigned long pfn)
355 {
356 	struct meminfo *mi = &meminfo;
357 	unsigned int left = 0, right = mi->nr_banks;
358 
359 	do {
360 		unsigned int mid = (right + left) / 2;
361 		struct membank *bank = &mi->bank[mid];
362 
363 		if (pfn < bank_pfn_start(bank))
364 			right = mid;
365 		else if (pfn >= bank_pfn_end(bank))
366 			left = mid + 1;
367 		else
368 			return 1;
369 	} while (left < right);
370 	return 0;
371 }
372 EXPORT_SYMBOL(pfn_valid);
373 #endif
374 
375 static int __init meminfo_cmp(const void *_a, const void *_b)
376 {
377 	const struct membank *a = _a, *b = _b;
378 	long cmp = bank_pfn_start(a) - bank_pfn_start(b);
379 	return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
380 }
381 
382 void __init bootmem_init(void)
383 {
384 	struct meminfo *mi = &meminfo;
385 	unsigned long min, max_low, max_high;
386 	int node, initrd_node;
387 
388 	sort(&mi->bank, mi->nr_banks, sizeof(mi->bank[0]), meminfo_cmp, NULL);
389 
390 	/*
391 	 * Locate which node contains the ramdisk image, if any.
392 	 */
393 	initrd_node = check_initrd(mi);
394 
395 	max_low = max_high = 0;
396 
397 	/*
398 	 * Run through each node initialising the bootmem allocator.
399 	 */
400 	for_each_node(node) {
401 		unsigned long node_low, node_high;
402 
403 		find_node_limits(node, mi, &min, &node_low, &node_high);
404 
405 		if (node_low > max_low)
406 			max_low = node_low;
407 		if (node_high > max_high)
408 			max_high = node_high;
409 
410 		/*
411 		 * If there is no memory in this node, ignore it.
412 		 * (We can't have nodes which have no lowmem)
413 		 */
414 		if (node_low == 0)
415 			continue;
416 
417 		bootmem_init_node(node, mi, min, node_low);
418 
419 		/*
420 		 * Reserve any special node zero regions.
421 		 */
422 		if (node == 0)
423 			reserve_node_zero(NODE_DATA(node));
424 
425 		/*
426 		 * If the initrd is in this node, reserve its memory.
427 		 */
428 		if (node == initrd_node)
429 			bootmem_reserve_initrd(node);
430 	}
431 
432 	/*
433 	 * sparse_init() needs the bootmem allocator up and running.
434 	 */
435 	sparse_init();
436 
437 	/*
438 	 * Now free memory in each node - free_area_init_node needs
439 	 * the sparse mem_map arrays initialized by sparse_init()
440 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
441 	 */
442 	for_each_node(node)
443 		bootmem_free_node(node, mi);
444 
445 	high_memory = __va((max_low << PAGE_SHIFT) - 1) + 1;
446 
447 	/*
448 	 * This doesn't seem to be used by the Linux memory manager any
449 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
450 	 * also get rid of some of the stuff above as well.
451 	 *
452 	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
453 	 * the system, not the maximum PFN.
454 	 */
455 	max_low_pfn = max_low - PHYS_PFN_OFFSET;
456 	max_pfn = max_high - PHYS_PFN_OFFSET;
457 }
458 
459 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
460 {
461 	unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
462 
463 	for (; pfn < end; pfn++) {
464 		struct page *page = pfn_to_page(pfn);
465 		ClearPageReserved(page);
466 		init_page_count(page);
467 		__free_page(page);
468 		pages++;
469 	}
470 
471 	if (size && s)
472 		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
473 
474 	return pages;
475 }
476 
477 static inline void
478 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
479 {
480 	struct page *start_pg, *end_pg;
481 	unsigned long pg, pgend;
482 
483 	/*
484 	 * Convert start_pfn/end_pfn to a struct page pointer.
485 	 */
486 	start_pg = pfn_to_page(start_pfn);
487 	end_pg = pfn_to_page(end_pfn);
488 
489 	/*
490 	 * Convert to physical addresses, and
491 	 * round start upwards and end downwards.
492 	 */
493 	pg = PAGE_ALIGN(__pa(start_pg));
494 	pgend = __pa(end_pg) & PAGE_MASK;
495 
496 	/*
497 	 * If there are free pages between these,
498 	 * free the section of the memmap array.
499 	 */
500 	if (pg < pgend)
501 		free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
502 }
503 
504 /*
505  * The mem_map array can get very big.  Free the unused area of the memory map.
506  */
507 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
508 {
509 	unsigned long bank_start, prev_bank_end = 0;
510 	unsigned int i;
511 
512 	/*
513 	 * [FIXME] This relies on each bank being in address order.  This
514 	 * may not be the case, especially if the user has provided the
515 	 * information on the command line.
516 	 */
517 	for_each_nodebank(i, mi, node) {
518 		struct membank *bank = &mi->bank[i];
519 
520 		bank_start = bank_pfn_start(bank);
521 		if (bank_start < prev_bank_end) {
522 			printk(KERN_ERR "MEM: unordered memory banks.  "
523 				"Not freeing memmap.\n");
524 			break;
525 		}
526 
527 		/*
528 		 * If we had a previous bank, and there is a space
529 		 * between the current bank and the previous, free it.
530 		 */
531 		if (prev_bank_end && prev_bank_end != bank_start)
532 			free_memmap(node, prev_bank_end, bank_start);
533 
534 		prev_bank_end = bank_pfn_end(bank);
535 	}
536 }
537 
538 /*
539  * mem_init() marks the free areas in the mem_map and tells us how much
540  * memory is free.  This is done after various parts of the system have
541  * claimed their memory after the kernel image.
542  */
543 void __init mem_init(void)
544 {
545 	unsigned int codesize, datasize, initsize;
546 	int i, node;
547 
548 #ifndef CONFIG_DISCONTIGMEM
549 	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
550 #endif
551 
552 	/* this will put all unused low memory onto the freelists */
553 	for_each_online_node(node) {
554 		pg_data_t *pgdat = NODE_DATA(node);
555 
556 		free_unused_memmap_node(node, &meminfo);
557 
558 		if (pgdat->node_spanned_pages != 0)
559 			totalram_pages += free_all_bootmem_node(pgdat);
560 	}
561 
562 #ifdef CONFIG_SA1111
563 	/* now that our DMA memory is actually so designated, we can free it */
564 	totalram_pages += free_area(PHYS_PFN_OFFSET,
565 				    __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
566 #endif
567 
568 #ifdef CONFIG_HIGHMEM
569 	/* set highmem page free */
570 	for_each_online_node(node) {
571 		for_each_nodebank (i, &meminfo, node) {
572 			unsigned long start = bank_pfn_start(&meminfo.bank[i]);
573 			unsigned long end = bank_pfn_end(&meminfo.bank[i]);
574 			if (start >= max_low_pfn + PHYS_PFN_OFFSET)
575 				totalhigh_pages += free_area(start, end, NULL);
576 		}
577 	}
578 	totalram_pages += totalhigh_pages;
579 #endif
580 
581 	/*
582 	 * Since our memory may not be contiguous, calculate the
583 	 * real number of pages we have in this system
584 	 */
585 	printk(KERN_INFO "Memory:");
586 	num_physpages = 0;
587 	for (i = 0; i < meminfo.nr_banks; i++) {
588 		num_physpages += bank_pfn_size(&meminfo.bank[i]);
589 		printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
590 	}
591 	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
592 
593 	codesize = _etext - _text;
594 	datasize = _end - _data;
595 	initsize = __init_end - __init_begin;
596 
597 	printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
598 		"%dK data, %dK init, %luK highmem)\n",
599 		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
600 		codesize >> 10, datasize >> 10, initsize >> 10,
601 		(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
602 
603 	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
604 		extern int sysctl_overcommit_memory;
605 		/*
606 		 * On a machine this small we won't get
607 		 * anywhere without overcommit, so turn
608 		 * it on by default.
609 		 */
610 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
611 	}
612 }
613 
614 void free_initmem(void)
615 {
616 	if (!machine_is_integrator() && !machine_is_cintegrator())
617 		totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
618 					    __phys_to_pfn(__pa(__init_end)),
619 					    "init");
620 }
621 
622 #ifdef CONFIG_BLK_DEV_INITRD
623 
624 static int keep_initrd;
625 
626 void free_initrd_mem(unsigned long start, unsigned long end)
627 {
628 	if (!keep_initrd)
629 		totalram_pages += free_area(__phys_to_pfn(__pa(start)),
630 					    __phys_to_pfn(__pa(end)),
631 					    "initrd");
632 }
633 
634 static int __init keepinitrd_setup(char *__unused)
635 {
636 	keep_initrd = 1;
637 	return 1;
638 }
639 
640 __setup("keepinitrd", keepinitrd_setup);
641 #endif
642