xref: /openbmc/linux/arch/arm/mm/init.c (revision 37efe642)
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 
19 #include <asm/mach-types.h>
20 #include <asm/sections.h>
21 #include <asm/setup.h>
22 #include <asm/sizes.h>
23 #include <asm/tlb.h>
24 
25 #include <asm/mach/arch.h>
26 #include <asm/mach/map.h>
27 
28 #include "mm.h"
29 
30 static unsigned long phys_initrd_start __initdata = 0;
31 static unsigned long phys_initrd_size __initdata = 0;
32 
33 static void __init early_initrd(char **p)
34 {
35 	unsigned long start, size;
36 
37 	start = memparse(*p, p);
38 	if (**p == ',') {
39 		size = memparse((*p) + 1, p);
40 
41 		phys_initrd_start = start;
42 		phys_initrd_size = size;
43 	}
44 }
45 __early_param("initrd=", early_initrd);
46 
47 static int __init parse_tag_initrd(const struct tag *tag)
48 {
49 	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
50 		"please update your bootloader.\n");
51 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
52 	phys_initrd_size = tag->u.initrd.size;
53 	return 0;
54 }
55 
56 __tagtable(ATAG_INITRD, parse_tag_initrd);
57 
58 static int __init parse_tag_initrd2(const struct tag *tag)
59 {
60 	phys_initrd_start = tag->u.initrd.start;
61 	phys_initrd_size = tag->u.initrd.size;
62 	return 0;
63 }
64 
65 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
66 
67 /*
68  * This keeps memory configuration data used by a couple memory
69  * initialization functions, as well as show_mem() for the skipping
70  * of holes in the memory map.  It is populated by arm_add_memory().
71  */
72 struct meminfo meminfo;
73 
74 void show_mem(void)
75 {
76 	int free = 0, total = 0, reserved = 0;
77 	int shared = 0, cached = 0, slab = 0, node, i;
78 	struct meminfo * mi = &meminfo;
79 
80 	printk("Mem-info:\n");
81 	show_free_areas();
82 	for_each_online_node(node) {
83 		pg_data_t *n = NODE_DATA(node);
84 		struct page *map = pgdat_page_nr(n, 0) - n->node_start_pfn;
85 
86 		for_each_nodebank (i,mi,node) {
87 			struct membank *bank = &mi->bank[i];
88 			unsigned int pfn1, pfn2;
89 			struct page *page, *end;
90 
91 			pfn1 = bank_pfn_start(bank);
92 			pfn2 = bank_pfn_end(bank);
93 
94 			page = map + pfn1;
95 			end  = map + pfn2;
96 
97 			do {
98 				total++;
99 				if (PageReserved(page))
100 					reserved++;
101 				else if (PageSwapCache(page))
102 					cached++;
103 				else if (PageSlab(page))
104 					slab++;
105 				else if (!page_count(page))
106 					free++;
107 				else
108 					shared += page_count(page) - 1;
109 				page++;
110 			} while (page < end);
111 		}
112 	}
113 
114 	printk("%d pages of RAM\n", total);
115 	printk("%d free pages\n", free);
116 	printk("%d reserved pages\n", reserved);
117 	printk("%d slab pages\n", slab);
118 	printk("%d pages shared\n", shared);
119 	printk("%d pages swap cached\n", cached);
120 }
121 
122 /*
123  * FIXME: We really want to avoid allocating the bootmap bitmap
124  * over the top of the initrd.  Hopefully, this is located towards
125  * the start of a bank, so if we allocate the bootmap bitmap at
126  * the end, we won't clash.
127  */
128 static unsigned int __init
129 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
130 {
131 	unsigned int start_pfn, i, bootmap_pfn;
132 
133 	start_pfn   = PAGE_ALIGN(__pa(_end)) >> PAGE_SHIFT;
134 	bootmap_pfn = 0;
135 
136 	for_each_nodebank(i, mi, node) {
137 		struct membank *bank = &mi->bank[i];
138 		unsigned int start, end;
139 
140 		start = bank_pfn_start(bank);
141 		end   = bank_pfn_end(bank);
142 
143 		if (end < start_pfn)
144 			continue;
145 
146 		if (start < start_pfn)
147 			start = start_pfn;
148 
149 		if (end <= start)
150 			continue;
151 
152 		if (end - start >= bootmap_pages) {
153 			bootmap_pfn = start;
154 			break;
155 		}
156 	}
157 
158 	if (bootmap_pfn == 0)
159 		BUG();
160 
161 	return bootmap_pfn;
162 }
163 
164 static int __init check_initrd(struct meminfo *mi)
165 {
166 	int initrd_node = -2;
167 #ifdef CONFIG_BLK_DEV_INITRD
168 	unsigned long end = phys_initrd_start + phys_initrd_size;
169 
170 	/*
171 	 * Make sure that the initrd is within a valid area of
172 	 * memory.
173 	 */
174 	if (phys_initrd_size) {
175 		unsigned int i;
176 
177 		initrd_node = -1;
178 
179 		for (i = 0; i < mi->nr_banks; i++) {
180 			struct membank *bank = &mi->bank[i];
181 			if (bank_phys_start(bank) <= phys_initrd_start &&
182 			    end <= bank_phys_end(bank))
183 				initrd_node = bank->node;
184 		}
185 	}
186 
187 	if (initrd_node == -1) {
188 		printk(KERN_ERR "INITRD: 0x%08lx+0x%08lx extends beyond "
189 		       "physical memory - disabling initrd\n",
190 		       phys_initrd_start, phys_initrd_size);
191 		phys_initrd_start = phys_initrd_size = 0;
192 	}
193 #endif
194 
195 	return initrd_node;
196 }
197 
198 static inline void map_memory_bank(struct membank *bank)
199 {
200 #ifdef CONFIG_MMU
201 	struct map_desc map;
202 
203 	map.pfn = bank_pfn_start(bank);
204 	map.virtual = __phys_to_virt(bank_phys_start(bank));
205 	map.length = bank_phys_size(bank);
206 	map.type = MT_MEMORY;
207 
208 	create_mapping(&map);
209 #endif
210 }
211 
212 static unsigned long __init bootmem_init_node(int node, struct meminfo *mi)
213 {
214 	unsigned long start_pfn, end_pfn, boot_pfn;
215 	unsigned int boot_pages;
216 	pg_data_t *pgdat;
217 	int i;
218 
219 	start_pfn = -1UL;
220 	end_pfn = 0;
221 
222 	/*
223 	 * Calculate the pfn range, and map the memory banks for this node.
224 	 */
225 	for_each_nodebank(i, mi, node) {
226 		struct membank *bank = &mi->bank[i];
227 		unsigned long start, end;
228 
229 		start = bank_pfn_start(bank);
230 		end = bank_pfn_end(bank);
231 
232 		if (start_pfn > start)
233 			start_pfn = start;
234 		if (end_pfn < end)
235 			end_pfn = end;
236 
237 		map_memory_bank(bank);
238 	}
239 
240 	/*
241 	 * If there is no memory in this node, ignore it.
242 	 */
243 	if (end_pfn == 0)
244 		return end_pfn;
245 
246 	/*
247 	 * Allocate the bootmem bitmap page.
248 	 */
249 	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
250 	boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
251 
252 	/*
253 	 * Initialise the bootmem allocator for this node, handing the
254 	 * memory banks over to bootmem.
255 	 */
256 	node_set_online(node);
257 	pgdat = NODE_DATA(node);
258 	init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
259 
260 	for_each_nodebank(i, mi, node) {
261 		struct membank *bank = &mi->bank[i];
262 		free_bootmem_node(pgdat, bank_phys_start(bank), bank_phys_size(bank));
263 		memory_present(node, bank_pfn_start(bank), bank_pfn_end(bank));
264 	}
265 
266 	/*
267 	 * Reserve the bootmem bitmap for this node.
268 	 */
269 	reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
270 			     boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
271 
272 	return end_pfn;
273 }
274 
275 static void __init bootmem_reserve_initrd(int node)
276 {
277 #ifdef CONFIG_BLK_DEV_INITRD
278 	pg_data_t *pgdat = NODE_DATA(node);
279 	int res;
280 
281 	res = reserve_bootmem_node(pgdat, phys_initrd_start,
282 			     phys_initrd_size, BOOTMEM_EXCLUSIVE);
283 
284 	if (res == 0) {
285 		initrd_start = __phys_to_virt(phys_initrd_start);
286 		initrd_end = initrd_start + phys_initrd_size;
287 	} else {
288 		printk(KERN_ERR
289 			"INITRD: 0x%08lx+0x%08lx overlaps in-use "
290 			"memory region - disabling initrd\n",
291 			phys_initrd_start, phys_initrd_size);
292 	}
293 #endif
294 }
295 
296 static void __init bootmem_free_node(int node, struct meminfo *mi)
297 {
298 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
299 	unsigned long start_pfn, end_pfn;
300 	pg_data_t *pgdat = NODE_DATA(node);
301 	int i;
302 
303 	start_pfn = pgdat->bdata->node_min_pfn;
304 	end_pfn = pgdat->bdata->node_low_pfn;
305 
306 	/*
307 	 * initialise the zones within this node.
308 	 */
309 	memset(zone_size, 0, sizeof(zone_size));
310 	memset(zhole_size, 0, sizeof(zhole_size));
311 
312 	/*
313 	 * The size of this node has already been determined.  If we need
314 	 * to do anything fancy with the allocation of this memory to the
315 	 * zones, now is the time to do it.
316 	 */
317 	zone_size[0] = end_pfn - start_pfn;
318 
319 	/*
320 	 * For each bank in this node, calculate the size of the holes.
321 	 *  holes = node_size - sum(bank_sizes_in_node)
322 	 */
323 	zhole_size[0] = zone_size[0];
324 	for_each_nodebank(i, mi, node)
325 		zhole_size[0] -= bank_pfn_size(&mi->bank[i]);
326 
327 	/*
328 	 * Adjust the sizes according to any special requirements for
329 	 * this machine type.
330 	 */
331 	arch_adjust_zones(node, zone_size, zhole_size);
332 
333 	free_area_init_node(node, zone_size, start_pfn, zhole_size);
334 }
335 
336 void __init bootmem_init(void)
337 {
338 	struct meminfo *mi = &meminfo;
339 	unsigned long memend_pfn = 0;
340 	int node, initrd_node;
341 
342 	/*
343 	 * Locate which node contains the ramdisk image, if any.
344 	 */
345 	initrd_node = check_initrd(mi);
346 
347 	/*
348 	 * Run through each node initialising the bootmem allocator.
349 	 */
350 	for_each_node(node) {
351 		unsigned long end_pfn = bootmem_init_node(node, mi);
352 
353 		/*
354 		 * Reserve any special node zero regions.
355 		 */
356 		if (node == 0)
357 			reserve_node_zero(NODE_DATA(node));
358 
359 		/*
360 		 * If the initrd is in this node, reserve its memory.
361 		 */
362 		if (node == initrd_node)
363 			bootmem_reserve_initrd(node);
364 
365 		/*
366 		 * Remember the highest memory PFN.
367 		 */
368 		if (end_pfn > memend_pfn)
369 			memend_pfn = end_pfn;
370 	}
371 
372 	/*
373 	 * sparse_init() needs the bootmem allocator up and running.
374 	 */
375 	sparse_init();
376 
377 	/*
378 	 * Now free memory in each node - free_area_init_node needs
379 	 * the sparse mem_map arrays initialized by sparse_init()
380 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
381 	 */
382 	for_each_node(node)
383 		bootmem_free_node(node, mi);
384 
385 	high_memory = __va(memend_pfn << PAGE_SHIFT);
386 
387 	/*
388 	 * This doesn't seem to be used by the Linux memory manager any
389 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
390 	 * also get rid of some of the stuff above as well.
391 	 *
392 	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
393 	 * the system, not the maximum PFN.
394 	 */
395 	max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
396 }
397 
398 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
399 {
400 	unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
401 
402 	for (; pfn < end; pfn++) {
403 		struct page *page = pfn_to_page(pfn);
404 		ClearPageReserved(page);
405 		init_page_count(page);
406 		__free_page(page);
407 		pages++;
408 	}
409 
410 	if (size && s)
411 		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
412 
413 	return pages;
414 }
415 
416 static inline void
417 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
418 {
419 	struct page *start_pg, *end_pg;
420 	unsigned long pg, pgend;
421 
422 	/*
423 	 * Convert start_pfn/end_pfn to a struct page pointer.
424 	 */
425 	start_pg = pfn_to_page(start_pfn);
426 	end_pg = pfn_to_page(end_pfn);
427 
428 	/*
429 	 * Convert to physical addresses, and
430 	 * round start upwards and end downwards.
431 	 */
432 	pg = PAGE_ALIGN(__pa(start_pg));
433 	pgend = __pa(end_pg) & PAGE_MASK;
434 
435 	/*
436 	 * If there are free pages between these,
437 	 * free the section of the memmap array.
438 	 */
439 	if (pg < pgend)
440 		free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
441 }
442 
443 /*
444  * The mem_map array can get very big.  Free the unused area of the memory map.
445  */
446 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
447 {
448 	unsigned long bank_start, prev_bank_end = 0;
449 	unsigned int i;
450 
451 	/*
452 	 * [FIXME] This relies on each bank being in address order.  This
453 	 * may not be the case, especially if the user has provided the
454 	 * information on the command line.
455 	 */
456 	for_each_nodebank(i, mi, node) {
457 		struct membank *bank = &mi->bank[i];
458 
459 		bank_start = bank_pfn_start(bank);
460 		if (bank_start < prev_bank_end) {
461 			printk(KERN_ERR "MEM: unordered memory banks.  "
462 				"Not freeing memmap.\n");
463 			break;
464 		}
465 
466 		/*
467 		 * If we had a previous bank, and there is a space
468 		 * between the current bank and the previous, free it.
469 		 */
470 		if (prev_bank_end && prev_bank_end != bank_start)
471 			free_memmap(node, prev_bank_end, bank_start);
472 
473 		prev_bank_end = bank_pfn_end(bank);
474 	}
475 }
476 
477 /*
478  * mem_init() marks the free areas in the mem_map and tells us how much
479  * memory is free.  This is done after various parts of the system have
480  * claimed their memory after the kernel image.
481  */
482 void __init mem_init(void)
483 {
484 	unsigned int codesize, datasize, initsize;
485 	int i, node;
486 
487 #ifndef CONFIG_DISCONTIGMEM
488 	max_mapnr   = virt_to_page(high_memory) - mem_map;
489 #endif
490 
491 	/* this will put all unused low memory onto the freelists */
492 	for_each_online_node(node) {
493 		pg_data_t *pgdat = NODE_DATA(node);
494 
495 		free_unused_memmap_node(node, &meminfo);
496 
497 		if (pgdat->node_spanned_pages != 0)
498 			totalram_pages += free_all_bootmem_node(pgdat);
499 	}
500 
501 #ifdef CONFIG_SA1111
502 	/* now that our DMA memory is actually so designated, we can free it */
503 	totalram_pages += free_area(PHYS_PFN_OFFSET,
504 				    __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
505 #endif
506 
507 	/*
508 	 * Since our memory may not be contiguous, calculate the
509 	 * real number of pages we have in this system
510 	 */
511 	printk(KERN_INFO "Memory:");
512 	num_physpages = 0;
513 	for (i = 0; i < meminfo.nr_banks; i++) {
514 		num_physpages += bank_pfn_size(&meminfo.bank[i]);
515 		printk(" %ldMB", bank_phys_size(&meminfo.bank[i]) >> 20);
516 	}
517 	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
518 
519 	codesize = _etext - _text;
520 	datasize = _end - _data;
521 	initsize = __init_end - __init_begin;
522 
523 	printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
524 		"%dK data, %dK init)\n",
525 		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
526 		codesize >> 10, datasize >> 10, initsize >> 10);
527 
528 	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
529 		extern int sysctl_overcommit_memory;
530 		/*
531 		 * On a machine this small we won't get
532 		 * anywhere without overcommit, so turn
533 		 * it on by default.
534 		 */
535 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
536 	}
537 }
538 
539 void free_initmem(void)
540 {
541 	if (!machine_is_integrator() && !machine_is_cintegrator())
542 		totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
543 					    __phys_to_pfn(__pa(__init_end)),
544 					    "init");
545 }
546 
547 #ifdef CONFIG_BLK_DEV_INITRD
548 
549 static int keep_initrd;
550 
551 void free_initrd_mem(unsigned long start, unsigned long end)
552 {
553 	if (!keep_initrd)
554 		totalram_pages += free_area(__phys_to_pfn(__pa(start)),
555 					    __phys_to_pfn(__pa(end)),
556 					    "initrd");
557 }
558 
559 static int __init keepinitrd_setup(char *__unused)
560 {
561 	keep_initrd = 1;
562 	return 1;
563 }
564 
565 __setup("keepinitrd", keepinitrd_setup);
566 #endif
567