1 /*
2  * Copyright (C) 2004-2006 Atmel Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/init.h>
11 #include <linux/initrd.h>
12 #include <linux/sched.h>
13 #include <linux/console.h>
14 #include <linux/ioport.h>
15 #include <linux/bootmem.h>
16 #include <linux/fs.h>
17 #include <linux/module.h>
18 #include <linux/pfn.h>
19 #include <linux/root_dev.h>
20 #include <linux/cpu.h>
21 #include <linux/kernel.h>
22 
23 #include <asm/sections.h>
24 #include <asm/processor.h>
25 #include <asm/pgtable.h>
26 #include <asm/setup.h>
27 #include <asm/sysreg.h>
28 
29 #include <mach/board.h>
30 #include <mach/init.h>
31 
32 extern int root_mountflags;
33 
34 /*
35  * Initialize loops_per_jiffy as 5000000 (500MIPS).
36  * Better make it too large than too small...
37  */
38 struct avr32_cpuinfo boot_cpu_data = {
39 	.loops_per_jiffy = 5000000
40 };
41 EXPORT_SYMBOL(boot_cpu_data);
42 
43 static char __initdata command_line[COMMAND_LINE_SIZE];
44 
45 /*
46  * Standard memory resources
47  */
48 static struct resource __initdata kernel_data = {
49 	.name	= "Kernel data",
50 	.start	= 0,
51 	.end	= 0,
52 	.flags	= IORESOURCE_MEM,
53 };
54 static struct resource __initdata kernel_code = {
55 	.name	= "Kernel code",
56 	.start	= 0,
57 	.end	= 0,
58 	.flags	= IORESOURCE_MEM,
59 	.sibling = &kernel_data,
60 };
61 
62 /*
63  * Available system RAM and reserved regions as singly linked
64  * lists. These lists are traversed using the sibling pointer in
65  * struct resource and are kept sorted at all times.
66  */
67 static struct resource *__initdata system_ram;
68 static struct resource *__initdata reserved = &kernel_code;
69 
70 /*
71  * We need to allocate these before the bootmem allocator is up and
72  * running, so we need this "cache". 32 entries are probably enough
73  * for all but the most insanely complex systems.
74  */
75 static struct resource __initdata res_cache[32];
76 static unsigned int __initdata res_cache_next_free;
77 
resource_init(void)78 static void __init resource_init(void)
79 {
80 	struct resource *mem, *res;
81 	struct resource *new;
82 
83 	kernel_code.start = __pa(init_mm.start_code);
84 
85 	for (mem = system_ram; mem; mem = mem->sibling) {
86 		new = alloc_bootmem_low(sizeof(struct resource));
87 		memcpy(new, mem, sizeof(struct resource));
88 
89 		new->sibling = NULL;
90 		if (request_resource(&iomem_resource, new))
91 			printk(KERN_WARNING "Bad RAM resource %08x-%08x\n",
92 			       mem->start, mem->end);
93 	}
94 
95 	for (res = reserved; res; res = res->sibling) {
96 		new = alloc_bootmem_low(sizeof(struct resource));
97 		memcpy(new, res, sizeof(struct resource));
98 
99 		new->sibling = NULL;
100 		if (insert_resource(&iomem_resource, new))
101 			printk(KERN_WARNING
102 			       "Bad reserved resource %s (%08x-%08x)\n",
103 			       res->name, res->start, res->end);
104 	}
105 }
106 
107 static void __init
add_physical_memory(resource_size_t start,resource_size_t end)108 add_physical_memory(resource_size_t start, resource_size_t end)
109 {
110 	struct resource *new, *next, **pprev;
111 
112 	for (pprev = &system_ram, next = system_ram; next;
113 	     pprev = &next->sibling, next = next->sibling) {
114 		if (end < next->start)
115 			break;
116 		if (start <= next->end) {
117 			printk(KERN_WARNING
118 			       "Warning: Physical memory map is broken\n");
119 			printk(KERN_WARNING
120 			       "Warning: %08x-%08x overlaps %08x-%08x\n",
121 			       start, end, next->start, next->end);
122 			return;
123 		}
124 	}
125 
126 	if (res_cache_next_free >= ARRAY_SIZE(res_cache)) {
127 		printk(KERN_WARNING
128 		       "Warning: Failed to add physical memory %08x-%08x\n",
129 		       start, end);
130 		return;
131 	}
132 
133 	new = &res_cache[res_cache_next_free++];
134 	new->start = start;
135 	new->end = end;
136 	new->name = "System RAM";
137 	new->flags = IORESOURCE_MEM;
138 
139 	*pprev = new;
140 }
141 
142 static int __init
add_reserved_region(resource_size_t start,resource_size_t end,const char * name)143 add_reserved_region(resource_size_t start, resource_size_t end,
144 		    const char *name)
145 {
146 	struct resource *new, *next, **pprev;
147 
148 	if (end < start)
149 		return -EINVAL;
150 
151 	if (res_cache_next_free >= ARRAY_SIZE(res_cache))
152 		return -ENOMEM;
153 
154 	for (pprev = &reserved, next = reserved; next;
155 	     pprev = &next->sibling, next = next->sibling) {
156 		if (end < next->start)
157 			break;
158 		if (start <= next->end)
159 			return -EBUSY;
160 	}
161 
162 	new = &res_cache[res_cache_next_free++];
163 	new->start = start;
164 	new->end = end;
165 	new->name = name;
166 	new->sibling = next;
167 	new->flags = IORESOURCE_MEM;
168 
169 	*pprev = new;
170 
171 	return 0;
172 }
173 
174 static unsigned long __init
find_free_region(const struct resource * mem,resource_size_t size,resource_size_t align)175 find_free_region(const struct resource *mem, resource_size_t size,
176 		 resource_size_t align)
177 {
178 	struct resource *res;
179 	unsigned long target;
180 
181 	target = ALIGN(mem->start, align);
182 	for (res = reserved; res; res = res->sibling) {
183 		if ((target + size) <= res->start)
184 			break;
185 		if (target <= res->end)
186 			target = ALIGN(res->end + 1, align);
187 	}
188 
189 	if ((target + size) > (mem->end + 1))
190 		return mem->end + 1;
191 
192 	return target;
193 }
194 
195 static int __init
alloc_reserved_region(resource_size_t * start,resource_size_t size,resource_size_t align,const char * name)196 alloc_reserved_region(resource_size_t *start, resource_size_t size,
197 		      resource_size_t align, const char *name)
198 {
199 	struct resource *mem;
200 	resource_size_t target;
201 	int ret;
202 
203 	for (mem = system_ram; mem; mem = mem->sibling) {
204 		target = find_free_region(mem, size, align);
205 		if (target <= mem->end) {
206 			ret = add_reserved_region(target, target + size - 1,
207 						  name);
208 			if (!ret)
209 				*start = target;
210 			return ret;
211 		}
212 	}
213 
214 	return -ENOMEM;
215 }
216 
217 /*
218  * Early framebuffer allocation. Works as follows:
219  *   - If fbmem_size is zero, nothing will be allocated or reserved.
220  *   - If fbmem_start is zero when setup_bootmem() is called,
221  *     a block of fbmem_size bytes will be reserved before bootmem
222  *     initialization. It will be aligned to the largest page size
223  *     that fbmem_size is a multiple of.
224  *   - If fbmem_start is nonzero, an area of size fbmem_size will be
225  *     reserved at the physical address fbmem_start if possible. If
226  *     it collides with other reserved memory, a different block of
227  *     same size will be allocated, just as if fbmem_start was zero.
228  *
229  * Board-specific code may use these variables to set up platform data
230  * for the framebuffer driver if fbmem_size is nonzero.
231  */
232 resource_size_t __initdata fbmem_start;
233 resource_size_t __initdata fbmem_size;
234 
235 /*
236  * "fbmem=xxx[kKmM]" allocates the specified amount of boot memory for
237  * use as framebuffer.
238  *
239  * "fbmem=xxx[kKmM]@yyy[kKmM]" defines a memory region of size xxx and
240  * starting at yyy to be reserved for use as framebuffer.
241  *
242  * The kernel won't verify that the memory region starting at yyy
243  * actually contains usable RAM.
244  */
early_parse_fbmem(char * p)245 static int __init early_parse_fbmem(char *p)
246 {
247 	int ret;
248 	unsigned long align;
249 
250 	fbmem_size = memparse(p, &p);
251 	if (*p == '@') {
252 		fbmem_start = memparse(p + 1, &p);
253 		ret = add_reserved_region(fbmem_start,
254 					  fbmem_start + fbmem_size - 1,
255 					  "Framebuffer");
256 		if (ret) {
257 			printk(KERN_WARNING
258 			       "Failed to reserve framebuffer memory\n");
259 			fbmem_start = 0;
260 		}
261 	}
262 
263 	if (!fbmem_start) {
264 		if ((fbmem_size & 0x000fffffUL) == 0)
265 			align = 0x100000;	/* 1 MiB */
266 		else if ((fbmem_size & 0x0000ffffUL) == 0)
267 			align = 0x10000;	/* 64 KiB */
268 		else
269 			align = 0x1000;		/* 4 KiB */
270 
271 		ret = alloc_reserved_region(&fbmem_start, fbmem_size,
272 					    align, "Framebuffer");
273 		if (ret) {
274 			printk(KERN_WARNING
275 			       "Failed to allocate framebuffer memory\n");
276 			fbmem_size = 0;
277 		} else {
278 			memset(__va(fbmem_start), 0, fbmem_size);
279 		}
280 	}
281 
282 	return 0;
283 }
284 early_param("fbmem", early_parse_fbmem);
285 
286 /*
287  * Pick out the memory size.  We look for mem=size@start,
288  * where start and size are "size[KkMmGg]"
289  */
early_mem(char * p)290 static int __init early_mem(char *p)
291 {
292 	resource_size_t size, start;
293 
294 	start = system_ram->start;
295 	size  = memparse(p, &p);
296 	if (*p == '@')
297 		start = memparse(p + 1, &p);
298 
299 	system_ram->start = start;
300 	system_ram->end = system_ram->start + size - 1;
301 	return 0;
302 }
303 early_param("mem", early_mem);
304 
parse_tag_core(struct tag * tag)305 static int __init parse_tag_core(struct tag *tag)
306 {
307 	if (tag->hdr.size > 2) {
308 		if ((tag->u.core.flags & 1) == 0)
309 			root_mountflags &= ~MS_RDONLY;
310 		ROOT_DEV = new_decode_dev(tag->u.core.rootdev);
311 	}
312 	return 0;
313 }
314 __tagtable(ATAG_CORE, parse_tag_core);
315 
parse_tag_mem(struct tag * tag)316 static int __init parse_tag_mem(struct tag *tag)
317 {
318 	unsigned long start, end;
319 
320 	/*
321 	 * Ignore zero-sized entries. If we're running standalone, the
322 	 * SDRAM code may emit such entries if something goes
323 	 * wrong...
324 	 */
325 	if (tag->u.mem_range.size == 0)
326 		return 0;
327 
328 	start = tag->u.mem_range.addr;
329 	end = tag->u.mem_range.addr + tag->u.mem_range.size - 1;
330 
331 	add_physical_memory(start, end);
332 	return 0;
333 }
334 __tagtable(ATAG_MEM, parse_tag_mem);
335 
parse_tag_rdimg(struct tag * tag)336 static int __init parse_tag_rdimg(struct tag *tag)
337 {
338 #ifdef CONFIG_BLK_DEV_INITRD
339 	struct tag_mem_range *mem = &tag->u.mem_range;
340 	int ret;
341 
342 	if (initrd_start) {
343 		printk(KERN_WARNING
344 		       "Warning: Only the first initrd image will be used\n");
345 		return 0;
346 	}
347 
348 	ret = add_reserved_region(mem->addr, mem->addr + mem->size - 1,
349 				  "initrd");
350 	if (ret) {
351 		printk(KERN_WARNING
352 		       "Warning: Failed to reserve initrd memory\n");
353 		return ret;
354 	}
355 
356 	initrd_start = (unsigned long)__va(mem->addr);
357 	initrd_end = initrd_start + mem->size;
358 #else
359 	printk(KERN_WARNING "RAM disk image present, but "
360 	       "no initrd support in kernel, ignoring\n");
361 #endif
362 
363 	return 0;
364 }
365 __tagtable(ATAG_RDIMG, parse_tag_rdimg);
366 
parse_tag_rsvd_mem(struct tag * tag)367 static int __init parse_tag_rsvd_mem(struct tag *tag)
368 {
369 	struct tag_mem_range *mem = &tag->u.mem_range;
370 
371 	return add_reserved_region(mem->addr, mem->addr + mem->size - 1,
372 				   "Reserved");
373 }
374 __tagtable(ATAG_RSVD_MEM, parse_tag_rsvd_mem);
375 
parse_tag_cmdline(struct tag * tag)376 static int __init parse_tag_cmdline(struct tag *tag)
377 {
378 	strlcpy(boot_command_line, tag->u.cmdline.cmdline, COMMAND_LINE_SIZE);
379 	return 0;
380 }
381 __tagtable(ATAG_CMDLINE, parse_tag_cmdline);
382 
parse_tag_clock(struct tag * tag)383 static int __init parse_tag_clock(struct tag *tag)
384 {
385 	/*
386 	 * We'll figure out the clocks by peeking at the system
387 	 * manager regs directly.
388 	 */
389 	return 0;
390 }
391 __tagtable(ATAG_CLOCK, parse_tag_clock);
392 
393 /*
394  * The board_number correspond to the bd->bi_board_number in U-Boot. This
395  * parameter is only available during initialisation and can be used in some
396  * kind of board identification.
397  */
398 u32 __initdata board_number;
399 
parse_tag_boardinfo(struct tag * tag)400 static int __init parse_tag_boardinfo(struct tag *tag)
401 {
402 	board_number = tag->u.boardinfo.board_number;
403 
404 	return 0;
405 }
406 __tagtable(ATAG_BOARDINFO, parse_tag_boardinfo);
407 
408 /*
409  * Scan the tag table for this tag, and call its parse function. The
410  * tag table is built by the linker from all the __tagtable
411  * declarations.
412  */
parse_tag(struct tag * tag)413 static int __init parse_tag(struct tag *tag)
414 {
415 	extern struct tagtable __tagtable_begin, __tagtable_end;
416 	struct tagtable *t;
417 
418 	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
419 		if (tag->hdr.tag == t->tag) {
420 			t->parse(tag);
421 			break;
422 		}
423 
424 	return t < &__tagtable_end;
425 }
426 
427 /*
428  * Parse all tags in the list we got from the boot loader
429  */
parse_tags(struct tag * t)430 static void __init parse_tags(struct tag *t)
431 {
432 	for (; t->hdr.tag != ATAG_NONE; t = tag_next(t))
433 		if (!parse_tag(t))
434 			printk(KERN_WARNING
435 			       "Ignoring unrecognised tag 0x%08x\n",
436 			       t->hdr.tag);
437 }
438 
439 /*
440  * Find a free memory region large enough for storing the
441  * bootmem bitmap.
442  */
443 static unsigned long __init
find_bootmap_pfn(const struct resource * mem)444 find_bootmap_pfn(const struct resource *mem)
445 {
446 	unsigned long bootmap_pages, bootmap_len;
447 	unsigned long node_pages = PFN_UP(mem->end - mem->start + 1);
448 	unsigned long bootmap_start;
449 
450 	bootmap_pages = bootmem_bootmap_pages(node_pages);
451 	bootmap_len = bootmap_pages << PAGE_SHIFT;
452 
453 	/*
454 	 * Find a large enough region without reserved pages for
455 	 * storing the bootmem bitmap. We can take advantage of the
456 	 * fact that all lists have been sorted.
457 	 *
458 	 * We have to check that we don't collide with any reserved
459 	 * regions, which includes the kernel image and any RAMDISK
460 	 * images.
461 	 */
462 	bootmap_start = find_free_region(mem, bootmap_len, PAGE_SIZE);
463 
464 	return bootmap_start >> PAGE_SHIFT;
465 }
466 
467 #define MAX_LOWMEM	HIGHMEM_START
468 #define MAX_LOWMEM_PFN	PFN_DOWN(MAX_LOWMEM)
469 
setup_bootmem(void)470 static void __init setup_bootmem(void)
471 {
472 	unsigned bootmap_size;
473 	unsigned long first_pfn, bootmap_pfn, pages;
474 	unsigned long max_pfn, max_low_pfn;
475 	unsigned node = 0;
476 	struct resource *res;
477 
478 	printk(KERN_INFO "Physical memory:\n");
479 	for (res = system_ram; res; res = res->sibling)
480 		printk("  %08x-%08x\n", res->start, res->end);
481 	printk(KERN_INFO "Reserved memory:\n");
482 	for (res = reserved; res; res = res->sibling)
483 		printk("  %08x-%08x: %s\n",
484 		       res->start, res->end, res->name);
485 
486 	nodes_clear(node_online_map);
487 
488 	if (system_ram->sibling)
489 		printk(KERN_WARNING "Only using first memory bank\n");
490 
491 	for (res = system_ram; res; res = NULL) {
492 		first_pfn = PFN_UP(res->start);
493 		max_low_pfn = max_pfn = PFN_DOWN(res->end + 1);
494 		bootmap_pfn = find_bootmap_pfn(res);
495 		if (bootmap_pfn > max_pfn)
496 			panic("No space for bootmem bitmap!\n");
497 
498 		if (max_low_pfn > MAX_LOWMEM_PFN) {
499 			max_low_pfn = MAX_LOWMEM_PFN;
500 #ifndef CONFIG_HIGHMEM
501 			/*
502 			 * Lowmem is memory that can be addressed
503 			 * directly through P1/P2
504 			 */
505 			printk(KERN_WARNING
506 			       "Node %u: Only %ld MiB of memory will be used.\n",
507 			       node, MAX_LOWMEM >> 20);
508 			printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
509 #else
510 #error HIGHMEM is not supported by AVR32 yet
511 #endif
512 		}
513 
514 		/* Initialize the boot-time allocator with low memory only. */
515 		bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn,
516 						 first_pfn, max_low_pfn);
517 
518 		/*
519 		 * Register fully available RAM pages with the bootmem
520 		 * allocator.
521 		 */
522 		pages = max_low_pfn - first_pfn;
523 		free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn),
524 				   PFN_PHYS(pages));
525 
526 		/* Reserve space for the bootmem bitmap... */
527 		reserve_bootmem_node(NODE_DATA(node),
528 				     PFN_PHYS(bootmap_pfn),
529 				     bootmap_size,
530 				     BOOTMEM_DEFAULT);
531 
532 		/* ...and any other reserved regions. */
533 		for (res = reserved; res; res = res->sibling) {
534 			if (res->start > PFN_PHYS(max_pfn))
535 				break;
536 
537 			/*
538 			 * resource_init will complain about partial
539 			 * overlaps, so we'll just ignore such
540 			 * resources for now.
541 			 */
542 			if (res->start >= PFN_PHYS(first_pfn)
543 			    && res->end < PFN_PHYS(max_pfn))
544 				reserve_bootmem_node(
545 					NODE_DATA(node), res->start,
546 					res->end - res->start + 1,
547 					BOOTMEM_DEFAULT);
548 		}
549 
550 		node_set_online(node);
551 	}
552 }
553 
setup_arch(char ** cmdline_p)554 void __init setup_arch (char **cmdline_p)
555 {
556 	struct clk *cpu_clk;
557 
558 	init_mm.start_code = (unsigned long)_text;
559 	init_mm.end_code = (unsigned long)_etext;
560 	init_mm.end_data = (unsigned long)_edata;
561 	init_mm.brk = (unsigned long)_end;
562 
563 	/*
564 	 * Include .init section to make allocations easier. It will
565 	 * be removed before the resource is actually requested.
566 	 */
567 	kernel_code.start = __pa(__init_begin);
568 	kernel_code.end = __pa(init_mm.end_code - 1);
569 	kernel_data.start = __pa(init_mm.end_code);
570 	kernel_data.end = __pa(init_mm.brk - 1);
571 
572 	parse_tags(bootloader_tags);
573 
574 	setup_processor();
575 	setup_platform();
576 	setup_board();
577 
578 	cpu_clk = clk_get(NULL, "cpu");
579 	if (IS_ERR(cpu_clk)) {
580 		printk(KERN_WARNING "Warning: Unable to get CPU clock\n");
581 	} else {
582 		unsigned long cpu_hz = clk_get_rate(cpu_clk);
583 
584 		/*
585 		 * Well, duh, but it's probably a good idea to
586 		 * increment the use count.
587 		 */
588 		clk_enable(cpu_clk);
589 
590 		boot_cpu_data.clk = cpu_clk;
591 		boot_cpu_data.loops_per_jiffy = cpu_hz * 4;
592 		printk("CPU: Running at %lu.%03lu MHz\n",
593 		       ((cpu_hz + 500) / 1000) / 1000,
594 		       ((cpu_hz + 500) / 1000) % 1000);
595 	}
596 
597 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
598 	*cmdline_p = command_line;
599 	parse_early_param();
600 
601 	setup_bootmem();
602 
603 #ifdef CONFIG_VT
604 	conswitchp = &dummy_con;
605 #endif
606 
607 	paging_init();
608 	resource_init();
609 }
610