xref: /openbmc/linux/arch/arm/kernel/setup.c (revision 171f1bc7)
1 /*
2  *  linux/arch/arm/kernel/setup.c
3  *
4  *  Copyright (C) 1995-2001 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/export.h>
11 #include <linux/kernel.h>
12 #include <linux/stddef.h>
13 #include <linux/ioport.h>
14 #include <linux/delay.h>
15 #include <linux/utsname.h>
16 #include <linux/initrd.h>
17 #include <linux/console.h>
18 #include <linux/bootmem.h>
19 #include <linux/seq_file.h>
20 #include <linux/screen_info.h>
21 #include <linux/init.h>
22 #include <linux/kexec.h>
23 #include <linux/of_fdt.h>
24 #include <linux/crash_dump.h>
25 #include <linux/root_dev.h>
26 #include <linux/cpu.h>
27 #include <linux/interrupt.h>
28 #include <linux/smp.h>
29 #include <linux/fs.h>
30 #include <linux/proc_fs.h>
31 #include <linux/memblock.h>
32 #include <linux/bug.h>
33 #include <linux/compiler.h>
34 
35 #include <asm/unified.h>
36 #include <asm/cpu.h>
37 #include <asm/cputype.h>
38 #include <asm/elf.h>
39 #include <asm/procinfo.h>
40 #include <asm/sections.h>
41 #include <asm/setup.h>
42 #include <asm/smp_plat.h>
43 #include <asm/mach-types.h>
44 #include <asm/cacheflush.h>
45 #include <asm/cachetype.h>
46 #include <asm/tlbflush.h>
47 #include <asm/system.h>
48 
49 #include <asm/prom.h>
50 #include <asm/mach/arch.h>
51 #include <asm/mach/irq.h>
52 #include <asm/mach/time.h>
53 #include <asm/traps.h>
54 #include <asm/unwind.h>
55 
56 #if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
57 #include "compat.h"
58 #endif
59 #include "atags.h"
60 #include "tcm.h"
61 
62 #ifndef MEM_SIZE
63 #define MEM_SIZE	(16*1024*1024)
64 #endif
65 
66 #if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
67 char fpe_type[8];
68 
69 static int __init fpe_setup(char *line)
70 {
71 	memcpy(fpe_type, line, 8);
72 	return 1;
73 }
74 
75 __setup("fpe=", fpe_setup);
76 #endif
77 
78 extern void paging_init(struct machine_desc *desc);
79 extern void sanity_check_meminfo(void);
80 extern void reboot_setup(char *str);
81 
82 unsigned int processor_id;
83 EXPORT_SYMBOL(processor_id);
84 unsigned int __machine_arch_type __read_mostly;
85 EXPORT_SYMBOL(__machine_arch_type);
86 unsigned int cacheid __read_mostly;
87 EXPORT_SYMBOL(cacheid);
88 
89 unsigned int __atags_pointer __initdata;
90 
91 unsigned int system_rev;
92 EXPORT_SYMBOL(system_rev);
93 
94 unsigned int system_serial_low;
95 EXPORT_SYMBOL(system_serial_low);
96 
97 unsigned int system_serial_high;
98 EXPORT_SYMBOL(system_serial_high);
99 
100 unsigned int elf_hwcap __read_mostly;
101 EXPORT_SYMBOL(elf_hwcap);
102 
103 
104 #ifdef MULTI_CPU
105 struct processor processor __read_mostly;
106 #endif
107 #ifdef MULTI_TLB
108 struct cpu_tlb_fns cpu_tlb __read_mostly;
109 #endif
110 #ifdef MULTI_USER
111 struct cpu_user_fns cpu_user __read_mostly;
112 #endif
113 #ifdef MULTI_CACHE
114 struct cpu_cache_fns cpu_cache __read_mostly;
115 #endif
116 #ifdef CONFIG_OUTER_CACHE
117 struct outer_cache_fns outer_cache __read_mostly;
118 EXPORT_SYMBOL(outer_cache);
119 #endif
120 
121 /*
122  * Cached cpu_architecture() result for use by assembler code.
123  * C code should use the cpu_architecture() function instead of accessing this
124  * variable directly.
125  */
126 int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
127 
128 struct stack {
129 	u32 irq[3];
130 	u32 abt[3];
131 	u32 und[3];
132 } ____cacheline_aligned;
133 
134 static struct stack stacks[NR_CPUS];
135 
136 char elf_platform[ELF_PLATFORM_SIZE];
137 EXPORT_SYMBOL(elf_platform);
138 
139 static const char *cpu_name;
140 static const char *machine_name;
141 static char __initdata cmd_line[COMMAND_LINE_SIZE];
142 struct machine_desc *machine_desc __initdata;
143 
144 static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
145 static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
146 #define ENDIANNESS ((char)endian_test.l)
147 
148 DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
149 
150 /*
151  * Standard memory resources
152  */
153 static struct resource mem_res[] = {
154 	{
155 		.name = "Video RAM",
156 		.start = 0,
157 		.end = 0,
158 		.flags = IORESOURCE_MEM
159 	},
160 	{
161 		.name = "Kernel text",
162 		.start = 0,
163 		.end = 0,
164 		.flags = IORESOURCE_MEM
165 	},
166 	{
167 		.name = "Kernel data",
168 		.start = 0,
169 		.end = 0,
170 		.flags = IORESOURCE_MEM
171 	}
172 };
173 
174 #define video_ram   mem_res[0]
175 #define kernel_code mem_res[1]
176 #define kernel_data mem_res[2]
177 
178 static struct resource io_res[] = {
179 	{
180 		.name = "reserved",
181 		.start = 0x3bc,
182 		.end = 0x3be,
183 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
184 	},
185 	{
186 		.name = "reserved",
187 		.start = 0x378,
188 		.end = 0x37f,
189 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
190 	},
191 	{
192 		.name = "reserved",
193 		.start = 0x278,
194 		.end = 0x27f,
195 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
196 	}
197 };
198 
199 #define lp0 io_res[0]
200 #define lp1 io_res[1]
201 #define lp2 io_res[2]
202 
203 static const char *proc_arch[] = {
204 	"undefined/unknown",
205 	"3",
206 	"4",
207 	"4T",
208 	"5",
209 	"5T",
210 	"5TE",
211 	"5TEJ",
212 	"6TEJ",
213 	"7",
214 	"?(11)",
215 	"?(12)",
216 	"?(13)",
217 	"?(14)",
218 	"?(15)",
219 	"?(16)",
220 	"?(17)",
221 };
222 
223 static int __get_cpu_architecture(void)
224 {
225 	int cpu_arch;
226 
227 	if ((read_cpuid_id() & 0x0008f000) == 0) {
228 		cpu_arch = CPU_ARCH_UNKNOWN;
229 	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
230 		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
231 	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
232 		cpu_arch = (read_cpuid_id() >> 16) & 7;
233 		if (cpu_arch)
234 			cpu_arch += CPU_ARCH_ARMv3;
235 	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
236 		unsigned int mmfr0;
237 
238 		/* Revised CPUID format. Read the Memory Model Feature
239 		 * Register 0 and check for VMSAv7 or PMSAv7 */
240 		asm("mrc	p15, 0, %0, c0, c1, 4"
241 		    : "=r" (mmfr0));
242 		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
243 		    (mmfr0 & 0x000000f0) >= 0x00000030)
244 			cpu_arch = CPU_ARCH_ARMv7;
245 		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
246 			 (mmfr0 & 0x000000f0) == 0x00000020)
247 			cpu_arch = CPU_ARCH_ARMv6;
248 		else
249 			cpu_arch = CPU_ARCH_UNKNOWN;
250 	} else
251 		cpu_arch = CPU_ARCH_UNKNOWN;
252 
253 	return cpu_arch;
254 }
255 
256 int __pure cpu_architecture(void)
257 {
258 	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
259 
260 	return __cpu_architecture;
261 }
262 
263 static int cpu_has_aliasing_icache(unsigned int arch)
264 {
265 	int aliasing_icache;
266 	unsigned int id_reg, num_sets, line_size;
267 
268 	/* PIPT caches never alias. */
269 	if (icache_is_pipt())
270 		return 0;
271 
272 	/* arch specifies the register format */
273 	switch (arch) {
274 	case CPU_ARCH_ARMv7:
275 		asm("mcr	p15, 2, %0, c0, c0, 0 @ set CSSELR"
276 		    : /* No output operands */
277 		    : "r" (1));
278 		isb();
279 		asm("mrc	p15, 1, %0, c0, c0, 0 @ read CCSIDR"
280 		    : "=r" (id_reg));
281 		line_size = 4 << ((id_reg & 0x7) + 2);
282 		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
283 		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
284 		break;
285 	case CPU_ARCH_ARMv6:
286 		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
287 		break;
288 	default:
289 		/* I-cache aliases will be handled by D-cache aliasing code */
290 		aliasing_icache = 0;
291 	}
292 
293 	return aliasing_icache;
294 }
295 
296 static void __init cacheid_init(void)
297 {
298 	unsigned int cachetype = read_cpuid_cachetype();
299 	unsigned int arch = cpu_architecture();
300 
301 	if (arch >= CPU_ARCH_ARMv6) {
302 		if ((cachetype & (7 << 29)) == 4 << 29) {
303 			/* ARMv7 register format */
304 			arch = CPU_ARCH_ARMv7;
305 			cacheid = CACHEID_VIPT_NONALIASING;
306 			switch (cachetype & (3 << 14)) {
307 			case (1 << 14):
308 				cacheid |= CACHEID_ASID_TAGGED;
309 				break;
310 			case (3 << 14):
311 				cacheid |= CACHEID_PIPT;
312 				break;
313 			}
314 		} else {
315 			arch = CPU_ARCH_ARMv6;
316 			if (cachetype & (1 << 23))
317 				cacheid = CACHEID_VIPT_ALIASING;
318 			else
319 				cacheid = CACHEID_VIPT_NONALIASING;
320 		}
321 		if (cpu_has_aliasing_icache(arch))
322 			cacheid |= CACHEID_VIPT_I_ALIASING;
323 	} else {
324 		cacheid = CACHEID_VIVT;
325 	}
326 
327 	printk("CPU: %s data cache, %s instruction cache\n",
328 		cache_is_vivt() ? "VIVT" :
329 		cache_is_vipt_aliasing() ? "VIPT aliasing" :
330 		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
331 		cache_is_vivt() ? "VIVT" :
332 		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
333 		icache_is_vipt_aliasing() ? "VIPT aliasing" :
334 		icache_is_pipt() ? "PIPT" :
335 		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
336 }
337 
338 /*
339  * These functions re-use the assembly code in head.S, which
340  * already provide the required functionality.
341  */
342 extern struct proc_info_list *lookup_processor_type(unsigned int);
343 
344 void __init early_print(const char *str, ...)
345 {
346 	extern void printascii(const char *);
347 	char buf[256];
348 	va_list ap;
349 
350 	va_start(ap, str);
351 	vsnprintf(buf, sizeof(buf), str, ap);
352 	va_end(ap);
353 
354 #ifdef CONFIG_DEBUG_LL
355 	printascii(buf);
356 #endif
357 	printk("%s", buf);
358 }
359 
360 static void __init feat_v6_fixup(void)
361 {
362 	int id = read_cpuid_id();
363 
364 	if ((id & 0xff0f0000) != 0x41070000)
365 		return;
366 
367 	/*
368 	 * HWCAP_TLS is available only on 1136 r1p0 and later,
369 	 * see also kuser_get_tls_init.
370 	 */
371 	if ((((id >> 4) & 0xfff) == 0xb36) && (((id >> 20) & 3) == 0))
372 		elf_hwcap &= ~HWCAP_TLS;
373 }
374 
375 /*
376  * cpu_init - initialise one CPU.
377  *
378  * cpu_init sets up the per-CPU stacks.
379  */
380 void cpu_init(void)
381 {
382 	unsigned int cpu = smp_processor_id();
383 	struct stack *stk = &stacks[cpu];
384 
385 	if (cpu >= NR_CPUS) {
386 		printk(KERN_CRIT "CPU%u: bad primary CPU number\n", cpu);
387 		BUG();
388 	}
389 
390 	cpu_proc_init();
391 
392 	/*
393 	 * Define the placement constraint for the inline asm directive below.
394 	 * In Thumb-2, msr with an immediate value is not allowed.
395 	 */
396 #ifdef CONFIG_THUMB2_KERNEL
397 #define PLC	"r"
398 #else
399 #define PLC	"I"
400 #endif
401 
402 	/*
403 	 * setup stacks for re-entrant exception handlers
404 	 */
405 	__asm__ (
406 	"msr	cpsr_c, %1\n\t"
407 	"add	r14, %0, %2\n\t"
408 	"mov	sp, r14\n\t"
409 	"msr	cpsr_c, %3\n\t"
410 	"add	r14, %0, %4\n\t"
411 	"mov	sp, r14\n\t"
412 	"msr	cpsr_c, %5\n\t"
413 	"add	r14, %0, %6\n\t"
414 	"mov	sp, r14\n\t"
415 	"msr	cpsr_c, %7"
416 	    :
417 	    : "r" (stk),
418 	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
419 	      "I" (offsetof(struct stack, irq[0])),
420 	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
421 	      "I" (offsetof(struct stack, abt[0])),
422 	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
423 	      "I" (offsetof(struct stack, und[0])),
424 	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
425 	    : "r14");
426 }
427 
428 static void __init setup_processor(void)
429 {
430 	struct proc_info_list *list;
431 
432 	/*
433 	 * locate processor in the list of supported processor
434 	 * types.  The linker builds this table for us from the
435 	 * entries in arch/arm/mm/proc-*.S
436 	 */
437 	list = lookup_processor_type(read_cpuid_id());
438 	if (!list) {
439 		printk("CPU configuration botched (ID %08x), unable "
440 		       "to continue.\n", read_cpuid_id());
441 		while (1);
442 	}
443 
444 	cpu_name = list->cpu_name;
445 	__cpu_architecture = __get_cpu_architecture();
446 
447 #ifdef MULTI_CPU
448 	processor = *list->proc;
449 #endif
450 #ifdef MULTI_TLB
451 	cpu_tlb = *list->tlb;
452 #endif
453 #ifdef MULTI_USER
454 	cpu_user = *list->user;
455 #endif
456 #ifdef MULTI_CACHE
457 	cpu_cache = *list->cache;
458 #endif
459 
460 	printk("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
461 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
462 	       proc_arch[cpu_architecture()], cr_alignment);
463 
464 	sprintf(init_utsname()->machine, "%s%c", list->arch_name, ENDIANNESS);
465 	sprintf(elf_platform, "%s%c", list->elf_name, ENDIANNESS);
466 	elf_hwcap = list->elf_hwcap;
467 #ifndef CONFIG_ARM_THUMB
468 	elf_hwcap &= ~HWCAP_THUMB;
469 #endif
470 
471 	feat_v6_fixup();
472 
473 	cacheid_init();
474 	cpu_init();
475 }
476 
477 void __init dump_machine_table(void)
478 {
479 	struct machine_desc *p;
480 
481 	early_print("Available machine support:\n\nID (hex)\tNAME\n");
482 	for_each_machine_desc(p)
483 		early_print("%08x\t%s\n", p->nr, p->name);
484 
485 	early_print("\nPlease check your kernel config and/or bootloader.\n");
486 
487 	while (true)
488 		/* can't use cpu_relax() here as it may require MMU setup */;
489 }
490 
491 int __init arm_add_memory(phys_addr_t start, unsigned long size)
492 {
493 	struct membank *bank = &meminfo.bank[meminfo.nr_banks];
494 
495 	if (meminfo.nr_banks >= NR_BANKS) {
496 		printk(KERN_CRIT "NR_BANKS too low, "
497 			"ignoring memory at 0x%08llx\n", (long long)start);
498 		return -EINVAL;
499 	}
500 
501 	/*
502 	 * Ensure that start/size are aligned to a page boundary.
503 	 * Size is appropriately rounded down, start is rounded up.
504 	 */
505 	size -= start & ~PAGE_MASK;
506 	bank->start = PAGE_ALIGN(start);
507 	bank->size  = size & PAGE_MASK;
508 
509 	/*
510 	 * Check whether this memory region has non-zero size or
511 	 * invalid node number.
512 	 */
513 	if (bank->size == 0)
514 		return -EINVAL;
515 
516 	meminfo.nr_banks++;
517 	return 0;
518 }
519 
520 /*
521  * Pick out the memory size.  We look for mem=size@start,
522  * where start and size are "size[KkMm]"
523  */
524 static int __init early_mem(char *p)
525 {
526 	static int usermem __initdata = 0;
527 	unsigned long size;
528 	phys_addr_t start;
529 	char *endp;
530 
531 	/*
532 	 * If the user specifies memory size, we
533 	 * blow away any automatically generated
534 	 * size.
535 	 */
536 	if (usermem == 0) {
537 		usermem = 1;
538 		meminfo.nr_banks = 0;
539 	}
540 
541 	start = PHYS_OFFSET;
542 	size  = memparse(p, &endp);
543 	if (*endp == '@')
544 		start = memparse(endp + 1, NULL);
545 
546 	arm_add_memory(start, size);
547 
548 	return 0;
549 }
550 early_param("mem", early_mem);
551 
552 static void __init
553 setup_ramdisk(int doload, int prompt, int image_start, unsigned int rd_sz)
554 {
555 #ifdef CONFIG_BLK_DEV_RAM
556 	extern int rd_size, rd_image_start, rd_prompt, rd_doload;
557 
558 	rd_image_start = image_start;
559 	rd_prompt = prompt;
560 	rd_doload = doload;
561 
562 	if (rd_sz)
563 		rd_size = rd_sz;
564 #endif
565 }
566 
567 static void __init request_standard_resources(struct machine_desc *mdesc)
568 {
569 	struct memblock_region *region;
570 	struct resource *res;
571 
572 	kernel_code.start   = virt_to_phys(_text);
573 	kernel_code.end     = virt_to_phys(_etext - 1);
574 	kernel_data.start   = virt_to_phys(_sdata);
575 	kernel_data.end     = virt_to_phys(_end - 1);
576 
577 	for_each_memblock(memory, region) {
578 		res = alloc_bootmem_low(sizeof(*res));
579 		res->name  = "System RAM";
580 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
581 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
582 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
583 
584 		request_resource(&iomem_resource, res);
585 
586 		if (kernel_code.start >= res->start &&
587 		    kernel_code.end <= res->end)
588 			request_resource(res, &kernel_code);
589 		if (kernel_data.start >= res->start &&
590 		    kernel_data.end <= res->end)
591 			request_resource(res, &kernel_data);
592 	}
593 
594 	if (mdesc->video_start) {
595 		video_ram.start = mdesc->video_start;
596 		video_ram.end   = mdesc->video_end;
597 		request_resource(&iomem_resource, &video_ram);
598 	}
599 
600 	/*
601 	 * Some machines don't have the possibility of ever
602 	 * possessing lp0, lp1 or lp2
603 	 */
604 	if (mdesc->reserve_lp0)
605 		request_resource(&ioport_resource, &lp0);
606 	if (mdesc->reserve_lp1)
607 		request_resource(&ioport_resource, &lp1);
608 	if (mdesc->reserve_lp2)
609 		request_resource(&ioport_resource, &lp2);
610 }
611 
612 /*
613  *  Tag parsing.
614  *
615  * This is the new way of passing data to the kernel at boot time.  Rather
616  * than passing a fixed inflexible structure to the kernel, we pass a list
617  * of variable-sized tags to the kernel.  The first tag must be a ATAG_CORE
618  * tag for the list to be recognised (to distinguish the tagged list from
619  * a param_struct).  The list is terminated with a zero-length tag (this tag
620  * is not parsed in any way).
621  */
622 static int __init parse_tag_core(const struct tag *tag)
623 {
624 	if (tag->hdr.size > 2) {
625 		if ((tag->u.core.flags & 1) == 0)
626 			root_mountflags &= ~MS_RDONLY;
627 		ROOT_DEV = old_decode_dev(tag->u.core.rootdev);
628 	}
629 	return 0;
630 }
631 
632 __tagtable(ATAG_CORE, parse_tag_core);
633 
634 static int __init parse_tag_mem32(const struct tag *tag)
635 {
636 	return arm_add_memory(tag->u.mem.start, tag->u.mem.size);
637 }
638 
639 __tagtable(ATAG_MEM, parse_tag_mem32);
640 
641 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
642 struct screen_info screen_info = {
643  .orig_video_lines	= 30,
644  .orig_video_cols	= 80,
645  .orig_video_mode	= 0,
646  .orig_video_ega_bx	= 0,
647  .orig_video_isVGA	= 1,
648  .orig_video_points	= 8
649 };
650 
651 static int __init parse_tag_videotext(const struct tag *tag)
652 {
653 	screen_info.orig_x            = tag->u.videotext.x;
654 	screen_info.orig_y            = tag->u.videotext.y;
655 	screen_info.orig_video_page   = tag->u.videotext.video_page;
656 	screen_info.orig_video_mode   = tag->u.videotext.video_mode;
657 	screen_info.orig_video_cols   = tag->u.videotext.video_cols;
658 	screen_info.orig_video_ega_bx = tag->u.videotext.video_ega_bx;
659 	screen_info.orig_video_lines  = tag->u.videotext.video_lines;
660 	screen_info.orig_video_isVGA  = tag->u.videotext.video_isvga;
661 	screen_info.orig_video_points = tag->u.videotext.video_points;
662 	return 0;
663 }
664 
665 __tagtable(ATAG_VIDEOTEXT, parse_tag_videotext);
666 #endif
667 
668 static int __init parse_tag_ramdisk(const struct tag *tag)
669 {
670 	setup_ramdisk((tag->u.ramdisk.flags & 1) == 0,
671 		      (tag->u.ramdisk.flags & 2) == 0,
672 		      tag->u.ramdisk.start, tag->u.ramdisk.size);
673 	return 0;
674 }
675 
676 __tagtable(ATAG_RAMDISK, parse_tag_ramdisk);
677 
678 static int __init parse_tag_serialnr(const struct tag *tag)
679 {
680 	system_serial_low = tag->u.serialnr.low;
681 	system_serial_high = tag->u.serialnr.high;
682 	return 0;
683 }
684 
685 __tagtable(ATAG_SERIAL, parse_tag_serialnr);
686 
687 static int __init parse_tag_revision(const struct tag *tag)
688 {
689 	system_rev = tag->u.revision.rev;
690 	return 0;
691 }
692 
693 __tagtable(ATAG_REVISION, parse_tag_revision);
694 
695 static int __init parse_tag_cmdline(const struct tag *tag)
696 {
697 #if defined(CONFIG_CMDLINE_EXTEND)
698 	strlcat(default_command_line, " ", COMMAND_LINE_SIZE);
699 	strlcat(default_command_line, tag->u.cmdline.cmdline,
700 		COMMAND_LINE_SIZE);
701 #elif defined(CONFIG_CMDLINE_FORCE)
702 	pr_warning("Ignoring tag cmdline (using the default kernel command line)\n");
703 #else
704 	strlcpy(default_command_line, tag->u.cmdline.cmdline,
705 		COMMAND_LINE_SIZE);
706 #endif
707 	return 0;
708 }
709 
710 __tagtable(ATAG_CMDLINE, parse_tag_cmdline);
711 
712 /*
713  * Scan the tag table for this tag, and call its parse function.
714  * The tag table is built by the linker from all the __tagtable
715  * declarations.
716  */
717 static int __init parse_tag(const struct tag *tag)
718 {
719 	extern struct tagtable __tagtable_begin, __tagtable_end;
720 	struct tagtable *t;
721 
722 	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
723 		if (tag->hdr.tag == t->tag) {
724 			t->parse(tag);
725 			break;
726 		}
727 
728 	return t < &__tagtable_end;
729 }
730 
731 /*
732  * Parse all tags in the list, checking both the global and architecture
733  * specific tag tables.
734  */
735 static void __init parse_tags(const struct tag *t)
736 {
737 	for (; t->hdr.size; t = tag_next(t))
738 		if (!parse_tag(t))
739 			printk(KERN_WARNING
740 				"Ignoring unrecognised tag 0x%08x\n",
741 				t->hdr.tag);
742 }
743 
744 /*
745  * This holds our defaults.
746  */
747 static struct init_tags {
748 	struct tag_header hdr1;
749 	struct tag_core   core;
750 	struct tag_header hdr2;
751 	struct tag_mem32  mem;
752 	struct tag_header hdr3;
753 } init_tags __initdata = {
754 	{ tag_size(tag_core), ATAG_CORE },
755 	{ 1, PAGE_SIZE, 0xff },
756 	{ tag_size(tag_mem32), ATAG_MEM },
757 	{ MEM_SIZE },
758 	{ 0, ATAG_NONE }
759 };
760 
761 static int __init customize_machine(void)
762 {
763 	/* customizes platform devices, or adds new ones */
764 	if (machine_desc->init_machine)
765 		machine_desc->init_machine();
766 	return 0;
767 }
768 arch_initcall(customize_machine);
769 
770 #ifdef CONFIG_KEXEC
771 static inline unsigned long long get_total_mem(void)
772 {
773 	unsigned long total;
774 
775 	total = max_low_pfn - min_low_pfn;
776 	return total << PAGE_SHIFT;
777 }
778 
779 /**
780  * reserve_crashkernel() - reserves memory are for crash kernel
781  *
782  * This function reserves memory area given in "crashkernel=" kernel command
783  * line parameter. The memory reserved is used by a dump capture kernel when
784  * primary kernel is crashing.
785  */
786 static void __init reserve_crashkernel(void)
787 {
788 	unsigned long long crash_size, crash_base;
789 	unsigned long long total_mem;
790 	int ret;
791 
792 	total_mem = get_total_mem();
793 	ret = parse_crashkernel(boot_command_line, total_mem,
794 				&crash_size, &crash_base);
795 	if (ret)
796 		return;
797 
798 	ret = reserve_bootmem(crash_base, crash_size, BOOTMEM_EXCLUSIVE);
799 	if (ret < 0) {
800 		printk(KERN_WARNING "crashkernel reservation failed - "
801 		       "memory is in use (0x%lx)\n", (unsigned long)crash_base);
802 		return;
803 	}
804 
805 	printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
806 	       "for crashkernel (System RAM: %ldMB)\n",
807 	       (unsigned long)(crash_size >> 20),
808 	       (unsigned long)(crash_base >> 20),
809 	       (unsigned long)(total_mem >> 20));
810 
811 	crashk_res.start = crash_base;
812 	crashk_res.end = crash_base + crash_size - 1;
813 	insert_resource(&iomem_resource, &crashk_res);
814 }
815 #else
816 static inline void reserve_crashkernel(void) {}
817 #endif /* CONFIG_KEXEC */
818 
819 static void __init squash_mem_tags(struct tag *tag)
820 {
821 	for (; tag->hdr.size; tag = tag_next(tag))
822 		if (tag->hdr.tag == ATAG_MEM)
823 			tag->hdr.tag = ATAG_NONE;
824 }
825 
826 static struct machine_desc * __init setup_machine_tags(unsigned int nr)
827 {
828 	struct tag *tags = (struct tag *)&init_tags;
829 	struct machine_desc *mdesc = NULL, *p;
830 	char *from = default_command_line;
831 
832 	init_tags.mem.start = PHYS_OFFSET;
833 
834 	/*
835 	 * locate machine in the list of supported machines.
836 	 */
837 	for_each_machine_desc(p)
838 		if (nr == p->nr) {
839 			printk("Machine: %s\n", p->name);
840 			mdesc = p;
841 			break;
842 		}
843 
844 	if (!mdesc) {
845 		early_print("\nError: unrecognized/unsupported machine ID"
846 			" (r1 = 0x%08x).\n\n", nr);
847 		dump_machine_table(); /* does not return */
848 	}
849 
850 	if (__atags_pointer)
851 		tags = phys_to_virt(__atags_pointer);
852 	else if (mdesc->atag_offset)
853 		tags = (void *)(PAGE_OFFSET + mdesc->atag_offset);
854 
855 #if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
856 	/*
857 	 * If we have the old style parameters, convert them to
858 	 * a tag list.
859 	 */
860 	if (tags->hdr.tag != ATAG_CORE)
861 		convert_to_tag_list(tags);
862 #endif
863 
864 	if (tags->hdr.tag != ATAG_CORE) {
865 #if defined(CONFIG_OF)
866 		/*
867 		 * If CONFIG_OF is set, then assume this is a reasonably
868 		 * modern system that should pass boot parameters
869 		 */
870 		early_print("Warning: Neither atags nor dtb found\n");
871 #endif
872 		tags = (struct tag *)&init_tags;
873 	}
874 
875 	if (mdesc->fixup)
876 		mdesc->fixup(tags, &from, &meminfo);
877 
878 	if (tags->hdr.tag == ATAG_CORE) {
879 		if (meminfo.nr_banks != 0)
880 			squash_mem_tags(tags);
881 		save_atags(tags);
882 		parse_tags(tags);
883 	}
884 
885 	/* parse_early_param needs a boot_command_line */
886 	strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
887 
888 	return mdesc;
889 }
890 
891 
892 void __init setup_arch(char **cmdline_p)
893 {
894 	struct machine_desc *mdesc;
895 
896 	unwind_init();
897 
898 	setup_processor();
899 	mdesc = setup_machine_fdt(__atags_pointer);
900 	if (!mdesc)
901 		mdesc = setup_machine_tags(machine_arch_type);
902 	machine_desc = mdesc;
903 	machine_name = mdesc->name;
904 
905 	if (mdesc->soft_reboot)
906 		reboot_setup("s");
907 
908 	init_mm.start_code = (unsigned long) _text;
909 	init_mm.end_code   = (unsigned long) _etext;
910 	init_mm.end_data   = (unsigned long) _edata;
911 	init_mm.brk	   = (unsigned long) _end;
912 
913 	/* populate cmd_line too for later use, preserving boot_command_line */
914 	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
915 	*cmdline_p = cmd_line;
916 
917 	parse_early_param();
918 
919 	sanity_check_meminfo();
920 	arm_memblock_init(&meminfo, mdesc);
921 
922 	paging_init(mdesc);
923 	request_standard_resources(mdesc);
924 
925 	unflatten_device_tree();
926 
927 #ifdef CONFIG_SMP
928 	if (is_smp())
929 		smp_init_cpus();
930 #endif
931 	reserve_crashkernel();
932 
933 	tcm_init();
934 
935 #ifdef CONFIG_ZONE_DMA
936 	if (mdesc->dma_zone_size) {
937 		extern unsigned long arm_dma_zone_size;
938 		arm_dma_zone_size = mdesc->dma_zone_size;
939 	}
940 #endif
941 #ifdef CONFIG_MULTI_IRQ_HANDLER
942 	handle_arch_irq = mdesc->handle_irq;
943 #endif
944 
945 #ifdef CONFIG_VT
946 #if defined(CONFIG_VGA_CONSOLE)
947 	conswitchp = &vga_con;
948 #elif defined(CONFIG_DUMMY_CONSOLE)
949 	conswitchp = &dummy_con;
950 #endif
951 #endif
952 	early_trap_init();
953 
954 	if (mdesc->init_early)
955 		mdesc->init_early();
956 }
957 
958 
959 static int __init topology_init(void)
960 {
961 	int cpu;
962 
963 	for_each_possible_cpu(cpu) {
964 		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
965 		cpuinfo->cpu.hotpluggable = 1;
966 		register_cpu(&cpuinfo->cpu, cpu);
967 	}
968 
969 	return 0;
970 }
971 subsys_initcall(topology_init);
972 
973 #ifdef CONFIG_HAVE_PROC_CPU
974 static int __init proc_cpu_init(void)
975 {
976 	struct proc_dir_entry *res;
977 
978 	res = proc_mkdir("cpu", NULL);
979 	if (!res)
980 		return -ENOMEM;
981 	return 0;
982 }
983 fs_initcall(proc_cpu_init);
984 #endif
985 
986 static const char *hwcap_str[] = {
987 	"swp",
988 	"half",
989 	"thumb",
990 	"26bit",
991 	"fastmult",
992 	"fpa",
993 	"vfp",
994 	"edsp",
995 	"java",
996 	"iwmmxt",
997 	"crunch",
998 	"thumbee",
999 	"neon",
1000 	"vfpv3",
1001 	"vfpv3d16",
1002 	"tls",
1003 	"vfpv4",
1004 	"idiva",
1005 	"idivt",
1006 	NULL
1007 };
1008 
1009 static int c_show(struct seq_file *m, void *v)
1010 {
1011 	int i;
1012 
1013 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
1014 		   cpu_name, read_cpuid_id() & 15, elf_platform);
1015 
1016 #if defined(CONFIG_SMP)
1017 	for_each_online_cpu(i) {
1018 		/*
1019 		 * glibc reads /proc/cpuinfo to determine the number of
1020 		 * online processors, looking for lines beginning with
1021 		 * "processor".  Give glibc what it expects.
1022 		 */
1023 		seq_printf(m, "processor\t: %d\n", i);
1024 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
1025 			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1026 			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1027 	}
1028 #else /* CONFIG_SMP */
1029 	seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1030 		   loops_per_jiffy / (500000/HZ),
1031 		   (loops_per_jiffy / (5000/HZ)) % 100);
1032 #endif
1033 
1034 	/* dump out the processor features */
1035 	seq_puts(m, "Features\t: ");
1036 
1037 	for (i = 0; hwcap_str[i]; i++)
1038 		if (elf_hwcap & (1 << i))
1039 			seq_printf(m, "%s ", hwcap_str[i]);
1040 
1041 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
1042 	seq_printf(m, "CPU architecture: %s\n", proc_arch[cpu_architecture()]);
1043 
1044 	if ((read_cpuid_id() & 0x0008f000) == 0x00000000) {
1045 		/* pre-ARM7 */
1046 		seq_printf(m, "CPU part\t: %07x\n", read_cpuid_id() >> 4);
1047 	} else {
1048 		if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
1049 			/* ARM7 */
1050 			seq_printf(m, "CPU variant\t: 0x%02x\n",
1051 				   (read_cpuid_id() >> 16) & 127);
1052 		} else {
1053 			/* post-ARM7 */
1054 			seq_printf(m, "CPU variant\t: 0x%x\n",
1055 				   (read_cpuid_id() >> 20) & 15);
1056 		}
1057 		seq_printf(m, "CPU part\t: 0x%03x\n",
1058 			   (read_cpuid_id() >> 4) & 0xfff);
1059 	}
1060 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
1061 
1062 	seq_puts(m, "\n");
1063 
1064 	seq_printf(m, "Hardware\t: %s\n", machine_name);
1065 	seq_printf(m, "Revision\t: %04x\n", system_rev);
1066 	seq_printf(m, "Serial\t\t: %08x%08x\n",
1067 		   system_serial_high, system_serial_low);
1068 
1069 	return 0;
1070 }
1071 
1072 static void *c_start(struct seq_file *m, loff_t *pos)
1073 {
1074 	return *pos < 1 ? (void *)1 : NULL;
1075 }
1076 
1077 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1078 {
1079 	++*pos;
1080 	return NULL;
1081 }
1082 
1083 static void c_stop(struct seq_file *m, void *v)
1084 {
1085 }
1086 
1087 const struct seq_operations cpuinfo_op = {
1088 	.start	= c_start,
1089 	.next	= c_next,
1090 	.stop	= c_stop,
1091 	.show	= c_show
1092 };
1093