summaryrefslogtreecommitdiffstats
path: root/arch/avr32/kernel/setup.c
blob: 53a1ff0cb05c37e055e0fa75593a8be5100bdc72 (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
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
/*
 * 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/clk.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/ioport.h>
#include <linux/bootmem.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/pfn.h>
#include <linux/root_dev.h>
#include <linux/cpu.h>
#include <linux/kernel.h>

#include <asm/sections.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
#include <asm/setup.h>
#include <asm/sysreg.h>

#include <asm/arch/board.h>
#include <asm/arch/init.h>

extern int root_mountflags;

/*
 * Bootloader-provided information about physical memory
 */
struct tag_mem_range *mem_phys;
struct tag_mem_range *mem_reserved;
struct tag_mem_range *mem_ramdisk;

/*
 * Initialize loops_per_jiffy as 5000000 (500MIPS).
 * Better make it too large than too small...
 */
struct avr32_cpuinfo boot_cpu_data = {
	.loops_per_jiffy = 5000000
};
EXPORT_SYMBOL(boot_cpu_data);

static char __initdata command_line[COMMAND_LINE_SIZE];

/*
 * Should be more than enough, but if you have a _really_ complex
 * setup, you might need to increase the size of this...
 */
static struct tag_mem_range __initdata mem_range_cache[32];
static unsigned mem_range_next_free;

/*
 * Standard memory resources
 */
static struct resource mem_res[] = {
	{
		.name	= "Kernel code",
		.start	= 0,
		.end	= 0,
		.flags	= IORESOURCE_MEM
	},
	{
		.name	= "Kernel data",
		.start	= 0,
		.end	= 0,
		.flags	= IORESOURCE_MEM,
	},
};

#define kernel_code	mem_res[0]
#define kernel_data	mem_res[1]

/*
 * Early framebuffer allocation. Works as follows:
 *   - If fbmem_size is zero, nothing will be allocated or reserved.
 *   - If fbmem_start is zero when setup_bootmem() is called,
 *     fbmem_size bytes will be allocated from the bootmem allocator.
 *   - If fbmem_start is nonzero, an area of size fbmem_size will be
 *     reserved at the physical address fbmem_start if necessary. If
 *     the area isn't in a memory region known to the kernel, it will
 *     be left alone.
 *
 * Board-specific code may use these variables to set up platform data
 * for the framebuffer driver if fbmem_size is nonzero.
 */
static unsigned long __initdata fbmem_start;
static unsigned long __initdata fbmem_size;

/*
 * "fbmem=xxx[kKmM]" allocates the specified amount of boot memory for
 * use as framebuffer.
 *
 * "fbmem=xxx[kKmM]@yyy[kKmM]" defines a memory region of size xxx and
 * starting at yyy to be reserved for use as framebuffer.
 *
 * The kernel won't verify that the memory region starting at yyy
 * actually contains usable RAM.
 */
static int __init early_parse_fbmem(char *p)
{
	fbmem_size = memparse(p, &p);
	if (*p == '@')
		fbmem_start = memparse(p, &p);
	return 0;
}
early_param("fbmem", early_parse_fbmem);

static inline void __init resource_init(void)
{
	struct tag_mem_range *region;

	kernel_code.start = __pa(init_mm.start_code);
	kernel_code.end = __pa(init_mm.end_code - 1);
	kernel_data.start = __pa(init_mm.end_code);
	kernel_data.end = __pa(init_mm.brk - 1);

	for (region = mem_phys; region; region = region->next) {
		struct resource *res;
		unsigned long phys_start, phys_end;

		if (region->size == 0)
			continue;

		phys_start = region->addr;
		phys_end = phys_start + region->size - 1;

		res = alloc_bootmem_low(sizeof(*res));
		res->name = "System RAM";
		res->start = phys_start;
		res->end = phys_end;
		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;

		request_resource (&iomem_resource, res);

		if (kernel_code.start >= res->start &&
		    kernel_code.end <= res->end)
			request_resource (res, &kernel_code);
		if (kernel_data.start >= res->start &&
		    kernel_data.end <= res->end)
			request_resource (res, &kernel_data);
	}
}

static int __init parse_tag_core(struct tag *tag)
{
	if (tag->hdr.size > 2) {
		if ((tag->u.core.flags & 1) == 0)
			root_mountflags &= ~MS_RDONLY;
		ROOT_DEV = new_decode_dev(tag->u.core.rootdev);
	}
	return 0;
}
__tagtable(ATAG_CORE, parse_tag_core);

static int __init parse_tag_mem_range(struct tag *tag,
				      struct tag_mem_range **root)
{
	struct tag_mem_range *cur, **pprev;
	struct tag_mem_range *new;

	/*
	 * Ignore zero-sized entries. If we're running standalone, the
	 * SDRAM code may emit such entries if something goes
	 * wrong...
	 */
	if (tag->u.mem_range.size == 0)
		return 0;

	/*
	 * Copy the data so the bootmem init code doesn't need to care
	 * about it.
	 */
	if (mem_range_next_free >= ARRAY_SIZE(mem_range_cache))
		panic("Physical memory map too complex!\n");

	new = &mem_range_cache[mem_range_next_free++];
	*new = tag->u.mem_range;

	pprev = root;
	cur = *root;
	while (cur) {
		pprev = &cur->next;
		cur = cur->next;
	}

	*pprev = new;
	new->next = NULL;

	return 0;
}

static int __init parse_tag_mem(struct tag *tag)
{
	return parse_tag_mem_range(tag, &mem_phys);
}
__tagtable(ATAG_MEM, parse_tag_mem);

static int __init parse_tag_cmdline(struct tag *tag)
{
	strlcpy(boot_command_line, tag->u.cmdline.cmdline, COMMAND_LINE_SIZE);
	return 0;
}
__tagtable(ATAG_CMDLINE, parse_tag_cmdline);

static int __init parse_tag_rdimg(struct tag *tag)
{
	return parse_tag_mem_range(tag, &mem_ramdisk);
}
__tagtable(ATAG_RDIMG, parse_tag_rdimg);

static int __init parse_tag_clock(struct tag *tag)
{
	/*
	 * We'll figure out the clocks by peeking at the system
	 * manager regs directly.
	 */
	return 0;
}
__tagtable(ATAG_CLOCK, parse_tag_clock);

static int __init parse_tag_rsvd_mem(struct tag *tag)
{
	return parse_tag_mem_range(tag, &mem_reserved);
}
__tagtable(ATAG_RSVD_MEM, parse_tag_rsvd_mem);

/*
 * Scan the tag table for this tag, and call its parse function. The
 * tag table is built by the linker from all the __tagtable
 * declarations.
 */
static int __init parse_tag(struct tag *tag)
{
	extern struct tagtable __tagtable_begin, __tagtable_end;
	struct tagtable *t;

	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
		if (tag->hdr.tag == t->tag) {
			t->parse(tag);
			break;
		}

	return t < &__tagtable_end;
}

/*
 * Parse all tags in the list we got from the boot loader
 */
static void __init parse_tags(struct tag *t)
{
	for (; t->hdr.tag != ATAG_NONE; t = tag_next(t))
		if (!parse_tag(t))
			printk(KERN_WARNING
			       "Ignoring unrecognised tag 0x%08x\n",
			       t->hdr.tag);
}

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 = __pa(_stext);
	unsigned long kern_end = __pa(_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);
}

static 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 = __pa(_stext);
	unsigned long kern_end = __pa(_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 = (unsigned long)__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);
	}
}

void __init setup_arch (char **cmdline_p)
{
	struct clk *cpu_clk;

	parse_tags(bootloader_tags);

	setup_processor();
	setup_platform();
	setup_board();

	cpu_clk = clk_get(NULL, "cpu");
	if (IS_ERR(cpu_clk)) {
		printk(KERN_WARNING "Warning: Unable to get CPU clock\n");
	} else {
		unsigned long cpu_hz = clk_get_rate(cpu_clk);

		/*
		 * Well, duh, but it's probably a good idea to
		 * increment the use count.
		 */
		clk_enable(cpu_clk);

		boot_cpu_data.clk = cpu_clk;
		boot_cpu_data.loops_per_jiffy = cpu_hz * 4;
		printk("CPU: Running at %lu.%03lu MHz\n",
		       ((cpu_hz + 500) / 1000) / 1000,
		       ((cpu_hz + 500) / 1000) % 1000);
	}

	init_mm.start_code = (unsigned long) &_text;
	init_mm.end_code = (unsigned long) &_etext;
	init_mm.end_data = (unsigned long) &_edata;
	init_mm.brk = (unsigned long) &_end;

	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
	*cmdline_p = command_line;
	parse_early_param();

	setup_bootmem();

	board_setup_fbmem(fbmem_start, fbmem_size);

#ifdef CONFIG_VT
	conswitchp = &dummy_con;
#endif

	paging_init();

	resource_init();
}