aboutsummaryrefslogtreecommitdiff
path: root/arch/avr32/mm/init.c
blob: 3e6c4103980855281164ea4acdfe945fa6819b85 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
/*
 * Copyright (C) 2004-2006 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/mmzone.h>
#include <linux/bootmem.h>
#include <linux/pagemap.h>
#include <linux/pfn.h>
#include <linux/nodemask.h>

#include <asm/page.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/setup.h>
#include <asm/sections.h>

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

pgd_t swapper_pg_dir[PTRS_PER_PGD];

struct page *empty_zero_page;

/*
 * Cache of MMU context last used.
 */
unsigned long mmu_context_cache = NO_CONTEXT;

#define START_PFN	(NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
#define MAX_LOW_PFN	(NODE_DATA(0)->bdata->node_low_pfn)

void show_mem(void)
{
	int total = 0, reserved = 0, cached = 0;
	int slab = 0, free = 0, shared = 0;
	pg_data_t *pgdat;

	printk("Mem-info:\n");
	show_free_areas();

	for_each_online_pgdat(pgdat) {
		struct page *page, *end;

		page = pgdat->node_mem_map;
		end = page + pgdat->node_spanned_pages;

		do {
			total++;
			if (PageReserved(page))
				reserved++;
			else if (PageSwapCache(page))
				cached++;
			else if (PageSlab(page))
				slab++;
			else if (!page_count(page))
				free++;
			else
				shared += page_count(page) - 1;
			page++;
		} while (page < end);
	}

	printk ("%d pages of RAM\n", total);
	printk ("%d free pages\n", free);
	printk ("%d reserved pages\n", reserved);
	printk ("%d slab pages\n", slab);
	printk ("%d pages shared\n", shared);
	printk ("%d pages swap cached\n", cached);
}

static void __init print_memory_map(const char *what,
				    struct tag_mem_range *mem)
{
	printk ("%s:\n", what);
	for (; mem; mem = mem->next) {
		printk ("  %08lx - %08lx\n",
			(unsigned long)mem->addr,
			(unsigned long)(mem->addr + mem->size));
	}
}

#define MAX_LOWMEM	HIGHMEM_START
#define MAX_LOWMEM_PFN	PFN_DOWN(MAX_LOWMEM)

/*
 * Sort a list of memory regions in-place by ascending address.
 *
 * We're using bubble sort because we only have singly linked lists
 * with few elements.
 */
static void __init sort_mem_list(struct tag_mem_range **pmem)
{
	int done;
	struct tag_mem_range **a, **b;

	if (!*pmem)
		return;

	do {
		done = 1;
		a = pmem, b = &(*pmem)->next;
		while (*b) {
			if ((*a)->addr > (*b)->addr) {
				struct tag_mem_range *tmp;
				tmp = (*b)->next;
				(*b)->next = *a;
				*a = *b;
				*b = tmp;
				done = 0;
			}
			a = &(*a)->next;
			b = &(*a)->next;
		}
	} while (!done);
}

/*
 * Find a free memory region large enough for storing the
 * bootmem bitmap.
 */
static unsigned long __init
find_bootmap_pfn(const struct tag_mem_range *mem)
{
	unsigned long bootmap_pages, bootmap_len;
	unsigned long node_pages = PFN_UP(mem->size);
	unsigned long bootmap_addr = mem->addr;
	struct tag_mem_range *reserved = mem_reserved;
	struct tag_mem_range *ramdisk = mem_ramdisk;
	unsigned long kern_start = virt_to_phys(_stext);
	unsigned long kern_end = virt_to_phys(_end);

	bootmap_pages = bootmem_bootmap_pages(node_pages);
	bootmap_len = bootmap_pages << PAGE_SHIFT;

	/*
	 * Find a large enough region without reserved pages for
	 * storing the bootmem bitmap. We can take advantage of the
	 * fact that all lists have been sorted.
	 *
	 * We have to check explicitly reserved regions as well as the
	 * kernel image and any RAMDISK images...
	 *
	 * Oh, and we have to make sure we don't overwrite the taglist
	 * since we're going to use it until the bootmem allocator is
	 * fully up and running.
	 */
	while (1) {
		if ((bootmap_addr < kern_end) &&
		    ((bootmap_addr + bootmap_len) > kern_start))
			bootmap_addr = kern_end;

		while (reserved &&
		       (bootmap_addr >= (reserved->addr + reserved->size)))
			reserved = reserved->next;

		if (reserved &&
		    ((bootmap_addr + bootmap_len) >= reserved->addr)) {
			bootmap_addr = reserved->addr + reserved->size;
			continue;
		}

		while (ramdisk &&
		       (bootmap_addr >= (ramdisk->addr + ramdisk->size)))
			ramdisk = ramdisk->next;

		if (!ramdisk ||
		    ((bootmap_addr + bootmap_len) < ramdisk->addr))
			break;

		bootmap_addr = ramdisk->addr + ramdisk->size;
	}

	if ((PFN_UP(bootmap_addr) + bootmap_len) >= (mem->addr + mem->size))
		return ~0UL;

	return PFN_UP(bootmap_addr);
}

void __init setup_bootmem(void)
{
	unsigned bootmap_size;
	unsigned long first_pfn, bootmap_pfn, pages;
	unsigned long max_pfn, max_low_pfn;
	unsigned long kern_start = virt_to_phys(_stext);
	unsigned long kern_end = virt_to_phys(_end);
	unsigned node = 0;
	struct tag_mem_range *bank, *res;

	sort_mem_list(&mem_phys);
	sort_mem_list(&mem_reserved);

	print_memory_map("Physical memory", mem_phys);
	print_memory_map("Reserved memory", mem_reserved);

	nodes_clear(node_online_map);

	if (mem_ramdisk) {
#ifdef CONFIG_BLK_DEV_INITRD
		initrd_start = __va(mem_ramdisk->addr);
		initrd_end = initrd_start + mem_ramdisk->size;

		print_memory_map("RAMDISK images", mem_ramdisk);
		if (mem_ramdisk->next)
			printk(KERN_WARNING
			       "Warning: Only the first RAMDISK image "
			       "will be used\n");
		sort_mem_list(&mem_ramdisk);
#else
		printk(KERN_WARNING "RAM disk image present, but "
		       "no initrd support in kernel!\n");
#endif
	}

	if (mem_phys->next)
		printk(KERN_WARNING "Only using first memory bank\n");

	for (bank = mem_phys; bank; bank = NULL) {
		first_pfn = PFN_UP(bank->addr);
		max_low_pfn = max_pfn = PFN_DOWN(bank->addr + bank->size);
		bootmap_pfn = find_bootmap_pfn(bank);
		if (bootmap_pfn > max_pfn)
			panic("No space for bootmem bitmap!\n");

		if (max_low_pfn > MAX_LOWMEM_PFN) {
			max_low_pfn = MAX_LOWMEM_PFN;
#ifndef CONFIG_HIGHMEM
			/*
			 * Lowmem is memory that can be addressed
			 * directly through P1/P2
			 */
			printk(KERN_WARNING
			       "Node %u: Only %ld MiB of memory will be used.\n",
			       node, MAX_LOWMEM >> 20);
			printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
#else
#error HIGHMEM is not supported by AVR32 yet
#endif
		}

		/* Initialize the boot-time allocator with low memory only. */
		bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn,
						 first_pfn, max_low_pfn);

		printk("Node %u: bdata = %p, bdata->node_bootmem_map = %p\n",
		       node, NODE_DATA(node)->bdata,
		       NODE_DATA(node)->bdata->node_bootmem_map);

		/*
		 * Register fully available RAM pages with the bootmem
		 * allocator.
		 */
		pages = max_low_pfn - first_pfn;
		free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn),
				   PFN_PHYS(pages));

		/*
		 * Reserve space for the kernel image (if present in
		 * this node)...
		 */
		if ((kern_start >= PFN_PHYS(first_pfn)) &&
		    (kern_start < PFN_PHYS(max_pfn))) {
			printk("Node %u: Kernel image %08lx - %08lx\n",
			       node, kern_start, kern_end);
			reserve_bootmem_node(NODE_DATA(node), kern_start,
					     kern_end - kern_start);
		}

		/* ...the bootmem bitmap... */
		reserve_bootmem_node(NODE_DATA(node),
				     PFN_PHYS(bootmap_pfn),
				     bootmap_size);

		/* ...any RAMDISK images... */
		for (res = mem_ramdisk; res; res = res->next) {
			if (res->addr > PFN_PHYS(max_pfn))
				break;

			if (res->addr >= PFN_PHYS(first_pfn)) {
				printk("Node %u: RAMDISK %08lx - %08lx\n",
				       node,
				       (unsigned long)res->addr,
				       (unsigned long)(res->addr + res->size));
				reserve_bootmem_node(NODE_DATA(node),
						     res->addr, res->size);
			}
		}

		/* ...and any other reserved regions. */
		for (res = mem_reserved; res; res = res->next) {
			if (res->addr > PFN_PHYS(max_pfn))
				break;

			if (res->addr >= PFN_PHYS(first_pfn)) {
				printk("Node %u: Reserved %08lx - %08lx\n",
				       node,
				       (unsigned long)res->addr,
				       (unsigned long)(res->addr + res->size));
				reserve_bootmem_node(NODE_DATA(node),
						     res->addr, res->size);
			}
		}

		node_set_online(node);
	}
}

/*
 * paging_init() sets up the page tables
 *
 * This routine also unmaps the page at virtual kernel address 0, so
 * that we can trap those pesky NULL-reference errors in the kernel.
 */
void __init paging_init(void)
{
	extern unsigned long _evba;
	void *zero_page;
	int nid;

	/*
	 * Make sure we can handle exceptions before enabling
	 * paging. Not that we should ever _get_ any exceptions this
	 * early, but you never know...
	 */
	printk("Exception vectors start at %p\n", &_evba);
	sysreg_write(EVBA, (unsigned long)&_evba);

	/*
	 * Since we are ready to handle exceptions now, we should let
	 * the CPU generate them...
	 */
	__asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));

	/*
	 * Allocate the zero page. The allocator will panic if it
	 * can't satisfy the request, so no need to check.
	 */
	zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
						 PAGE_SIZE);

	{
		pgd_t *pg_dir;
		int i;

		pg_dir = swapper_pg_dir;
		sysreg_write(PTBR, (unsigned long)pg_dir);

		for (i = 0; i < PTRS_PER_PGD; i++)
			pgd_val(pg_dir[i]) = 0;

		enable_mmu();
		printk ("CPU: Paging enabled\n");
	}

	for_each_online_node(nid) {
		pg_data_t *pgdat = NODE_DATA(nid);
		unsigned long zones_size[MAX_NR_ZONES];
		unsigned long low, start_pfn;

		start_pfn = pgdat->bdata->node_boot_start;
		start_pfn >>= PAGE_SHIFT;
		low = pgdat->bdata->node_low_pfn;

		memset(zones_size, 0, sizeof(zones_size));
		zones_size[ZONE_NORMAL] = low - start_pfn;

		printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
		       nid, start_pfn, low);

		free_area_init_node(nid, pgdat, zones_size, start_pfn, NULL);

		printk("Node %u: mem_map starts at %p\n",
		       pgdat->node_id, pgdat->node_mem_map);
	}

	mem_map = NODE_DATA(0)->node_mem_map;

	memset(zero_page, 0, PAGE_SIZE);
	empty_zero_page = virt_to_page(zero_page);
	flush_dcache_page(empty_zero_page);
}

void __init mem_init(void)
{
	int codesize, reservedpages, datasize, initsize;
	int nid, i;

	reservedpages = 0;
	high_memory = NULL;

	/* this will put all low memory onto the freelists */
	for_each_online_node(nid) {
		pg_data_t *pgdat = NODE_DATA(nid);
		unsigned long node_pages = 0;
		void *node_high_memory;

		num_physpages += pgdat->node_present_pages;

		if (pgdat->node_spanned_pages != 0)
			node_pages = free_all_bootmem_node(pgdat);

		totalram_pages += node_pages;

		for (i = 0; i < node_pages; i++)
			if (PageReserved(pgdat->node_mem_map + i))
				reservedpages++;

		node_high_memory = (void *)((pgdat->node_start_pfn
					     + pgdat->node_spanned_pages)
					    << PAGE_SHIFT);
		if (node_high_memory > high_memory)
			high_memory = node_high_memory;
	}

	max_mapnr = MAP_NR(high_memory);

	codesize = (unsigned long)_etext - (unsigned long)_text;
	datasize = (unsigned long)_edata - (unsigned long)_data;
	initsize = (unsigned long)__init_end - (unsigned long)__init_begin;

	printk ("Memory: %luk/%luk available (%dk kernel code, "
		"%dk reserved, %dk data, %dk init)\n",
		(unsigned long)nr_free_pages() << (PAGE_SHIFT - 10),
		totalram_pages << (PAGE_SHIFT - 10),
		codesize >> 10,
		reservedpages << (PAGE_SHIFT - 10),
		datasize >> 10,
		initsize >> 10);
}

static inline void free_area(unsigned long addr, unsigned long end, char *s)
{
	unsigned int size = (end - addr) >> 10;

	for (; addr < end; addr += PAGE_SIZE) {
		struct page *page = virt_to_page(addr);
		ClearPageReserved(page);
		init_page_count(page);
		free_page(addr);
		totalram_pages++;
	}

	if (size && s)
		printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n",
		       s, size, end - (size << 10), end);
}

void free_initmem(void)
{
	free_area((unsigned long)__init_begin, (unsigned long)__init_end,
		  "init");
}

#ifdef CONFIG_BLK_DEV_INITRD

static int keep_initrd;

void free_initrd_mem(unsigned long start, unsigned long end)
{
	if (!keep_initrd)
		free_area(start, end, "initrd");
}

static int __init keepinitrd_setup(char *__unused)
{
	keep_initrd = 1;
	return 1;
}

__setup("keepinitrd", keepinitrd_setup);
#endif