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/setup.h>
21#include <asm/sizes.h>
22#include <asm/tlb.h>
23
24#include <asm/mach/arch.h>
25#include <asm/mach/map.h>
26
27#include "mm.h"
28
29extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
30extern unsigned long phys_initrd_start;
31extern unsigned long phys_initrd_size;
32
33/*
34 * This is used to pass memory configuration data from paging_init
35 * to mem_init, and by show_mem() to skip holes in the memory map.
36 */
37static struct meminfo meminfo = { 0, };
38
39#define for_each_nodebank(iter,mi,no)			\
40	for (iter = 0; iter < mi->nr_banks; iter++)	\
41		if (mi->bank[iter].node == no)
42
43void show_mem(void)
44{
45	int free = 0, total = 0, reserved = 0;
46	int shared = 0, cached = 0, slab = 0, node, i;
47	struct meminfo * mi = &meminfo;
48
49	printk("Mem-info:\n");
50	show_free_areas();
51	printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
52
53	for_each_online_node(node) {
54		pg_data_t *n = NODE_DATA(node);
55		struct page *map = n->node_mem_map - n->node_start_pfn;
56
57		for_each_nodebank (i,mi,node) {
58			unsigned int pfn1, pfn2;
59			struct page *page, *end;
60
61			pfn1 = __phys_to_pfn(mi->bank[i].start);
62			pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);
63
64			page = map + pfn1;
65			end  = map + pfn2;
66
67			do {
68				total++;
69				if (PageReserved(page))
70					reserved++;
71				else if (PageSwapCache(page))
72					cached++;
73				else if (PageSlab(page))
74					slab++;
75				else if (!page_count(page))
76					free++;
77				else
78					shared += page_count(page) - 1;
79				page++;
80			} while (page < end);
81		}
82	}
83
84	printk("%d pages of RAM\n", total);
85	printk("%d free pages\n", free);
86	printk("%d reserved pages\n", reserved);
87	printk("%d slab pages\n", slab);
88	printk("%d pages shared\n", shared);
89	printk("%d pages swap cached\n", cached);
90}
91
92static unsigned int __init
93find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
94{
95	unsigned int start_pfn, bank, bootmap_pfn;
96
97	start_pfn   = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
98	bootmap_pfn = 0;
99
100	for_each_nodebank(bank, mi, node) {
101		unsigned int start, end;
102
103		start = mi->bank[bank].start >> PAGE_SHIFT;
104		end   = (mi->bank[bank].size +
105			 mi->bank[bank].start) >> PAGE_SHIFT;
106
107		if (end < start_pfn)
108			continue;
109
110		if (start < start_pfn)
111			start = start_pfn;
112
113		if (end <= start)
114			continue;
115
116		if (end - start >= bootmap_pages) {
117			bootmap_pfn = start;
118			break;
119		}
120	}
121
122	if (bootmap_pfn == 0)
123		BUG();
124
125	return bootmap_pfn;
126}
127
128static int __init check_initrd(struct meminfo *mi)
129{
130	int initrd_node = -2;
131#ifdef CONFIG_BLK_DEV_INITRD
132	unsigned long end = phys_initrd_start + phys_initrd_size;
133
134	/*
135	 * Make sure that the initrd is within a valid area of
136	 * memory.
137	 */
138	if (phys_initrd_size) {
139		unsigned int i;
140
141		initrd_node = -1;
142
143		for (i = 0; i < mi->nr_banks; i++) {
144			unsigned long bank_end;
145
146			bank_end = mi->bank[i].start + mi->bank[i].size;
147
148			if (mi->bank[i].start <= phys_initrd_start &&
149			    end <= bank_end)
150				initrd_node = mi->bank[i].node;
151		}
152	}
153
154	if (initrd_node == -1) {
155		printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
156		       "physical memory - disabling initrd\n",
157		       phys_initrd_start, end);
158		phys_initrd_start = phys_initrd_size = 0;
159	}
160#endif
161
162	return initrd_node;
163}
164
165static inline void map_memory_bank(struct membank *bank)
166{
167#ifdef CONFIG_MMU
168	struct map_desc map;
169
170	map.pfn = __phys_to_pfn(bank->start);
171	map.virtual = __phys_to_virt(bank->start);
172	map.length = bank->size;
173	map.type = MT_MEMORY;
174
175	create_mapping(&map);
176#endif
177}
178
179static unsigned long __init
180bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
181{
182	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
183	unsigned long start_pfn, end_pfn, boot_pfn;
184	unsigned int boot_pages;
185	pg_data_t *pgdat;
186	int i;
187
188	start_pfn = -1UL;
189	end_pfn = 0;
190
191	/*
192	 * Calculate the pfn range, and map the memory banks for this node.
193	 */
194	for_each_nodebank(i, mi, node) {
195		struct membank *bank = &mi->bank[i];
196		unsigned long start, end;
197
198		start = bank->start >> PAGE_SHIFT;
199		end = (bank->start + bank->size) >> PAGE_SHIFT;
200
201		if (start_pfn > start)
202			start_pfn = start;
203		if (end_pfn < end)
204			end_pfn = end;
205
206		map_memory_bank(bank);
207	}
208
209	/*
210	 * If there is no memory in this node, ignore it.
211	 */
212	if (end_pfn == 0)
213		return end_pfn;
214
215	/*
216	 * Allocate the bootmem bitmap page.
217	 */
218	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
219	boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
220
221	/*
222	 * Initialise the bootmem allocator for this node, handing the
223	 * memory banks over to bootmem.
224	 */
225	node_set_online(node);
226	pgdat = NODE_DATA(node);
227	init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
228
229	for_each_nodebank(i, mi, node)
230		free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);
231
232	/*
233	 * Reserve the bootmem bitmap for this node.
234	 */
235	reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
236			     boot_pages << PAGE_SHIFT);
237
238#ifdef CONFIG_BLK_DEV_INITRD
239	/*
240	 * If the initrd is in this node, reserve its memory.
241	 */
242	if (node == initrd_node) {
243		reserve_bootmem_node(pgdat, phys_initrd_start,
244				     phys_initrd_size);
245		initrd_start = __phys_to_virt(phys_initrd_start);
246		initrd_end = initrd_start + phys_initrd_size;
247	}
248#endif
249
250	/*
251	 * Finally, reserve any node zero regions.
252	 */
253	if (node == 0)
254		reserve_node_zero(pgdat);
255
256	/*
257	 * initialise the zones within this node.
258	 */
259	memset(zone_size, 0, sizeof(zone_size));
260	memset(zhole_size, 0, sizeof(zhole_size));
261
262	/*
263	 * The size of this node has already been determined.  If we need
264	 * to do anything fancy with the allocation of this memory to the
265	 * zones, now is the time to do it.
266	 */
267	zone_size[0] = end_pfn - start_pfn;
268
269	/*
270	 * For each bank in this node, calculate the size of the holes.
271	 *  holes = node_size - sum(bank_sizes_in_node)
272	 */
273	zhole_size[0] = zone_size[0];
274	for_each_nodebank(i, mi, node)
275		zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
276
277	/*
278	 * Adjust the sizes according to any special requirements for
279	 * this machine type.
280	 */
281	arch_adjust_zones(node, zone_size, zhole_size);
282
283	free_area_init_node(node, pgdat, zone_size, start_pfn, zhole_size);
284
285	return end_pfn;
286}
287
288void __init bootmem_init(struct meminfo *mi)
289{
290	unsigned long memend_pfn = 0;
291	int node, initrd_node, i;
292
293	/*
294	 * Invalidate the node number for empty or invalid memory banks
295	 */
296	for (i = 0; i < mi->nr_banks; i++)
297		if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
298			mi->bank[i].node = -1;
299
300	memcpy(&meminfo, mi, sizeof(meminfo));
301
302	/*
303	 * Locate which node contains the ramdisk image, if any.
304	 */
305	initrd_node = check_initrd(mi);
306
307	/*
308	 * Run through each node initialising the bootmem allocator.
309	 */
310	for_each_node(node) {
311		unsigned long end_pfn;
312
313		end_pfn = bootmem_init_node(node, initrd_node, mi);
314
315		/*
316		 * Remember the highest memory PFN.
317		 */
318		if (end_pfn > memend_pfn)
319			memend_pfn = end_pfn;
320	}
321
322	high_memory = __va(memend_pfn << PAGE_SHIFT);
323
324	/*
325	 * This doesn't seem to be used by the Linux memory manager any
326	 * more, but is used by ll_rw_block.  If we can get rid of it, we
327	 * also get rid of some of the stuff above as well.
328	 *
329	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
330	 * the system, not the maximum PFN.
331	 */
332	max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
333}
334
335static inline void free_area(unsigned long addr, unsigned long end, char *s)
336{
337	unsigned int size = (end - addr) >> 10;
338
339	for (; addr < end; addr += PAGE_SIZE) {
340		struct page *page = virt_to_page(addr);
341		ClearPageReserved(page);
342		init_page_count(page);
343		free_page(addr);
344		totalram_pages++;
345	}
346
347	if (size && s)
348		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
349}
350
351static inline void
352free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
353{
354	struct page *start_pg, *end_pg;
355	unsigned long pg, pgend;
356
357	/*
358	 * Convert start_pfn/end_pfn to a struct page pointer.
359	 */
360	start_pg = pfn_to_page(start_pfn);
361	end_pg = pfn_to_page(end_pfn);
362
363	/*
364	 * Convert to physical addresses, and
365	 * round start upwards and end downwards.
366	 */
367	pg = PAGE_ALIGN(__pa(start_pg));
368	pgend = __pa(end_pg) & PAGE_MASK;
369
370	/*
371	 * If there are free pages between these,
372	 * free the section of the memmap array.
373	 */
374	if (pg < pgend)
375		free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
376}
377
378/*
379 * The mem_map array can get very big.  Free the unused area of the memory map.
380 */
381static void __init free_unused_memmap_node(int node, struct meminfo *mi)
382{
383	unsigned long bank_start, prev_bank_end = 0;
384	unsigned int i;
385
386	for_each_nodebank(i, mi, node) {
387		bank_start = mi->bank[i].start >> PAGE_SHIFT;
388		if (bank_start < prev_bank_end) {
389			printk(KERN_ERR "MEM: unordered memory banks.  "
390				"Not freeing memmap.\n");
391			break;
392		}
393
394		/*
395		 * If we had a previous bank, and there is a space
396		 * between the current bank and the previous, free it.
397		 */
398		if (prev_bank_end && prev_bank_end != bank_start)
399			free_memmap(node, prev_bank_end, bank_start);
400
401		prev_bank_end = (mi->bank[i].start +
402				 mi->bank[i].size) >> PAGE_SHIFT;
403	}
404}
405
406/*
407 * mem_init() marks the free areas in the mem_map and tells us how much
408 * memory is free.  This is done after various parts of the system have
409 * claimed their memory after the kernel image.
410 */
411void __init mem_init(void)
412{
413	unsigned int codepages, datapages, initpages;
414	int i, node;
415
416	codepages = &_etext - &_text;
417	datapages = &_end - &__data_start;
418	initpages = &__init_end - &__init_begin;
419
420#ifndef CONFIG_DISCONTIGMEM
421	max_mapnr   = virt_to_page(high_memory) - mem_map;
422#endif
423
424	/* this will put all unused low memory onto the freelists */
425	for_each_online_node(node) {
426		pg_data_t *pgdat = NODE_DATA(node);
427
428		free_unused_memmap_node(node, &meminfo);
429
430		if (pgdat->node_spanned_pages != 0)
431			totalram_pages += free_all_bootmem_node(pgdat);
432	}
433
434#ifdef CONFIG_SA1111
435	/* now that our DMA memory is actually so designated, we can free it */
436	free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
437#endif
438
439	/*
440	 * Since our memory may not be contiguous, calculate the
441	 * real number of pages we have in this system
442	 */
443	printk(KERN_INFO "Memory:");
444
445	num_physpages = 0;
446	for (i = 0; i < meminfo.nr_banks; i++) {
447		num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
448		printk(" %ldMB", meminfo.bank[i].size >> 20);
449	}
450
451	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
452	printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
453		"%dK data, %dK init)\n",
454		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
455		codepages >> 10, datapages >> 10, initpages >> 10);
456
457	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
458		extern int sysctl_overcommit_memory;
459		/*
460		 * On a machine this small we won't get
461		 * anywhere without overcommit, so turn
462		 * it on by default.
463		 */
464		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
465	}
466}
467
468void free_initmem(void)
469{
470	if (!machine_is_integrator() && !machine_is_cintegrator()) {
471		free_area((unsigned long)(&__init_begin),
472			  (unsigned long)(&__init_end),
473			  "init");
474	}
475}
476
477#ifdef CONFIG_BLK_DEV_INITRD
478
479static int keep_initrd;
480
481void free_initrd_mem(unsigned long start, unsigned long end)
482{
483	if (!keep_initrd)
484		free_area(start, end, "initrd");
485}
486
487static int __init keepinitrd_setup(char *__unused)
488{
489	keep_initrd = 1;
490	return 1;
491}
492
493__setup("keepinitrd", keepinitrd_setup);
494#endif
495