setup.c

linux 内核源代码

					from += len;
					p->fn(&from);

					while (*from != ' ' && *from != '\0')
						from++;
					break;
				}
			}
		}
		c = *from++;
		if (!c)
			break;
		if (COMMAND_LINE_SIZE <= ++len)
			break;
		*to++ = c;
	}
	*to = '\0';
	*cmdline_p = command_line;
}

static void __init
setup_ramdisk(int doload, int prompt, int image_start, unsigned int rd_sz)
{
#ifdef CONFIG_BLK_DEV_RAM
	extern int rd_size, rd_image_start, rd_prompt, rd_doload;

	rd_image_start = image_start;
	rd_prompt = prompt;
	rd_doload = doload;

	if (rd_sz)
		rd_size = rd_sz;
#endif
}

static void __init
request_standard_resources(struct meminfo *mi, struct machine_desc *mdesc)
{
	struct resource *res;
	int i;

	kernel_code.start   = virt_to_phys(&_text);
	kernel_code.end     = virt_to_phys(&_etext - 1);
	kernel_data.start   = virt_to_phys(&__data_start);
	kernel_data.end     = virt_to_phys(&_end - 1);

	for (i = 0; i < mi->nr_banks; i++) {
		unsigned long virt_start, virt_end;

		if (mi->bank[i].size == 0)
			continue;

		virt_start = __phys_to_virt(mi->bank[i].start);
		virt_end   = virt_start + mi->bank[i].size - 1;

		res = alloc_bootmem_low(sizeof(*res));
		res->name  = "System RAM";
		res->start = __virt_to_phys(virt_start);
		res->end   = __virt_to_phys(virt_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);
	}

	if (mdesc->video_start) {
		video_ram.start = mdesc->video_start;
		video_ram.end   = mdesc->video_end;
		request_resource(&iomem_resource, &video_ram);
	}

	/*
	 * Some machines don't have the possibility of ever
	 * possessing lp0, lp1 or lp2
	 */
	if (mdesc->reserve_lp0)
		request_resource(&ioport_resource, &lp0);
	if (mdesc->reserve_lp1)
		request_resource(&ioport_resource, &lp1);
	if (mdesc->reserve_lp2)
		request_resource(&ioport_resource, &lp2);
}

/*
 *  Tag parsing.
 *
 * This is the new way of passing data to the kernel at boot time.  Rather
 * than passing a fixed inflexible structure to the kernel, we pass a list
 * of variable-sized tags to the kernel.  The first tag must be a ATAG_CORE
 * tag for the list to be recognised (to distinguish the tagged list from
 * a param_struct).  The list is terminated with a zero-length tag (this tag
 * is not parsed in any way).
 */
static int __init parse_tag_core(const struct tag *tag)
{
	if (tag->hdr.size > 2) {
		if ((tag->u.core.flags & 1) == 0)
			root_mountflags &= ~MS_RDONLY;
		ROOT_DEV = old_decode_dev(tag->u.core.rootdev);
	}
	return 0;
}

__tagtable(ATAG_CORE, parse_tag_core);

static int __init parse_tag_mem32(const struct tag *tag)
{
	if (meminfo.nr_banks >= NR_BANKS) {
		printk(KERN_WARNING
		       "Ignoring memory bank 0x%08x size %dKB\n",
			tag->u.mem.start, tag->u.mem.size / 1024);
		return -EINVAL;
	}
	arm_add_memory(tag->u.mem.start, tag->u.mem.size);
	return 0;
}

__tagtable(ATAG_MEM, parse_tag_mem32);

#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
struct screen_info screen_info = {
 .orig_video_lines	= 30,
 .orig_video_cols	= 80,
 .orig_video_mode	= 0,
 .orig_video_ega_bx	= 0,
 .orig_video_isVGA	= 1,
 .orig_video_points	= 8
};

static int __init parse_tag_videotext(const struct tag *tag)
{
	screen_info.orig_x            = tag->u.videotext.x;
	screen_info.orig_y            = tag->u.videotext.y;
	screen_info.orig_video_page   = tag->u.videotext.video_page;
	screen_info.orig_video_mode   = tag->u.videotext.video_mode;
	screen_info.orig_video_cols   = tag->u.videotext.video_cols;
	screen_info.orig_video_ega_bx = tag->u.videotext.video_ega_bx;
	screen_info.orig_video_lines  = tag->u.videotext.video_lines;
	screen_info.orig_video_isVGA  = tag->u.videotext.video_isvga;
	screen_info.orig_video_points = tag->u.videotext.video_points;
	return 0;
}

__tagtable(ATAG_VIDEOTEXT, parse_tag_videotext);
#endif

static int __init parse_tag_ramdisk(const struct tag *tag)
{
	setup_ramdisk((tag->u.ramdisk.flags & 1) == 0,
		      (tag->u.ramdisk.flags & 2) == 0,
		      tag->u.ramdisk.start, tag->u.ramdisk.size);
	return 0;
}

__tagtable(ATAG_RAMDISK, parse_tag_ramdisk);

static int __init parse_tag_initrd(const struct tag *tag)
{
	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
		"please update your bootloader.\n");
	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
	phys_initrd_size = tag->u.initrd.size;
	return 0;
}

__tagtable(ATAG_INITRD, parse_tag_initrd);

static int __init parse_tag_initrd2(const struct tag *tag)
{
	phys_initrd_start = tag->u.initrd.start;
	phys_initrd_size = tag->u.initrd.size;
	return 0;
}

__tagtable(ATAG_INITRD2, parse_tag_initrd2);

static int __init parse_tag_serialnr(const struct tag *tag)
{
	system_serial_low = tag->u.serialnr.low;
	system_serial_high = tag->u.serialnr.high;
	return 0;
}

__tagtable(ATAG_SERIAL, parse_tag_serialnr);

static int __init parse_tag_revision(const struct tag *tag)
{
	system_rev = tag->u.revision.rev;
	return 0;
}

__tagtable(ATAG_REVISION, parse_tag_revision);

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

__tagtable(ATAG_CMDLINE, parse_tag_cmdline);

/*
 * 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(const 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, checking both the global and architecture
 * specific tag tables.
 */
static void __init parse_tags(const struct tag *t)
{
	for (; t->hdr.size; t = tag_next(t))
		if (!parse_tag(t))
			printk(KERN_WARNING
				"Ignoring unrecognised tag 0x%08x\n",
				t->hdr.tag);
}

/*
 * This holds our defaults.
 */
static struct init_tags {
	struct tag_header hdr1;
	struct tag_core   core;
	struct tag_header hdr2;
	struct tag_mem32  mem;
	struct tag_header hdr3;
} init_tags __initdata = {
	{ tag_size(tag_core), ATAG_CORE },
	{ 1, PAGE_SIZE, 0xff },
	{ tag_size(tag_mem32), ATAG_MEM },
	{ MEM_SIZE, PHYS_OFFSET },
	{ 0, ATAG_NONE }
};

static void (*init_machine)(void) __initdata;

static int __init customize_machine(void)
{
	/* customizes platform devices, or adds new ones */
	if (init_machine)
		init_machine();
	return 0;
}
arch_initcall(customize_machine);

#ifdef CONFIG_KEXEC

/* Physical addr of where the boot params should be for this machine */
extern unsigned long kexec_boot_params_address;

/* Physical addr of the buffer into which the boot params are copied */
extern unsigned long kexec_boot_params_copy;

/* Pointer to the boot params buffer, for manipulation and display */
unsigned long kexec_boot_params;
EXPORT_SYMBOL(kexec_boot_params);

/* The buffer itself - make sure it is sized correctly */
static unsigned long kexec_boot_params_buf[(KEXEC_BOOT_PARAMS_SIZE + 3) / 4];

#endif

void __init setup_arch(char **cmdline_p)
{
	struct tag *tags = (struct tag *)&init_tags;
	struct machine_desc *mdesc;
	char *from = default_command_line;

	setup_processor();
	mdesc = setup_machine(machine_arch_type);
	machine_name = mdesc->name;

	if (mdesc->soft_reboot)
		reboot_setup("s");

	if (__atags_pointer)
		tags = phys_to_virt(__atags_pointer);
	else if (mdesc->boot_params)
		tags = phys_to_virt(mdesc->boot_params);

#ifdef CONFIG_KEXEC
	kexec_boot_params_copy = virt_to_phys(kexec_boot_params_buf);
	kexec_boot_params = (unsigned long)kexec_boot_params_buf;
	if (__atags_pointer) {
		kexec_boot_params_address = __atags_pointer;
		memcpy((void *)kexec_boot_params, tags, KEXEC_BOOT_PARAMS_SIZE);
	} else if (mdesc->boot_params) {
		kexec_boot_params_address = mdesc->boot_params;
		memcpy((void *)kexec_boot_params, tags, KEXEC_BOOT_PARAMS_SIZE);
	}
#endif

	/*
	 * If we have the old style parameters, convert them to
	 * a tag list.
	 */
	if (tags->hdr.tag != ATAG_CORE)
		convert_to_tag_list(tags);
	if (tags->hdr.tag != ATAG_CORE)
		tags = (struct tag *)&init_tags;

	if (mdesc->fixup)
		mdesc->fixup(mdesc, tags, &from, &meminfo);

	if (tags->hdr.tag == ATAG_CORE) {
		if (meminfo.nr_banks != 0)
			squash_mem_tags(tags);
		parse_tags(tags);
	}

	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;

	memcpy(boot_command_line, from, COMMAND_LINE_SIZE);
	boot_command_line[COMMAND_LINE_SIZE-1] = '\0';
	parse_cmdline(cmdline_p, from);
	paging_init(&meminfo, mdesc);
	request_standard_resources(&meminfo, mdesc);

#ifdef CONFIG_SMP
	smp_init_cpus();
#endif

	cpu_init();

	/*
	 * Set up various architecture-specific pointers
	 */
	init_arch_irq = mdesc->init_irq;
	system_timer = mdesc->timer;
	init_machine = mdesc->init_machine;

#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
	conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
	conswitchp = &dummy_con;
#endif
#endif
}


static int __init topology_init(void)
{
	int cpu;

	for_each_possible_cpu(cpu) {
		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
		cpuinfo->cpu.hotpluggable = 1;
		register_cpu(&cpuinfo->cpu, cpu);
	}

	return 0;
}

subsys_initcall(topology_init);

static const char *hwcap_str[] = {
	"swp",
	"half",
	"thumb",
	"26bit",
	"fastmult",
	"fpa",
	"vfp",
	"edsp",
	"java",
	"iwmmxt",
	"crunch",
	NULL
};

static void
c_show_cache(struct seq_file *m, const char *type, unsigned int cache)
{
	unsigned int mult = 2 + (CACHE_M(cache) ? 1 : 0);

	seq_printf(m, "%s size\t\t: %d\n"
		      "%s assoc\t\t: %d\n"
		      "%s line length\t: %d\n"
		      "%s sets\t\t: %d\n",
		type, mult << (8 + CACHE_SIZE(cache)),
		type, (mult << CACHE_ASSOC(cache)) >> 1,
		type, 8 << CACHE_LINE(cache),
		type, 1 << (6 + CACHE_SIZE(cache) - CACHE_ASSOC(cache) -
			    CACHE_LINE(cache)));
}

static int c_show(struct seq_file *m, void *v)
{
	int i;

	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
		   cpu_name, (int)processor_id & 15, elf_platform);

#if defined(CONFIG_SMP)
	for_each_online_cpu(i) {
		/*
		 * glibc reads /proc/cpuinfo to determine the number of
		 * online processors, looking for lines beginning with
		 * "processor".  Give glibc what it expects.
		 */
		seq_printf(m, "processor\t: %d\n", i);
		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
	}
#else /* CONFIG_SMP */
	seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
		   loops_per_jiffy / (500000/HZ),
		   (loops_per_jiffy / (5000/HZ)) % 100);
#endif

	/* dump out the processor features */
	seq_puts(m, "Features\t: ");

	for (i = 0; hwcap_str[i]; i++)
		if (elf_hwcap & (1 << i))
			seq_printf(m, "%s ", hwcap_str[i]);

	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", processor_id >> 24);
	seq_printf(m, "CPU architecture: %s\n", proc_arch[cpu_architecture()]);

	if ((processor_id & 0x0008f000) == 0x00000000) {
		/* pre-ARM7 */
		seq_printf(m, "CPU part\t: %07x\n", processor_id >> 4);
	} else {
		if ((processor_id & 0x0008f000) == 0x00007000) {
			/* ARM7 */
			seq_printf(m, "CPU variant\t: 0x%02x\n",
				   (processor_id >> 16) & 127);
		} else {
			/* post-ARM7 */
			seq_printf(m, "CPU variant\t: 0x%x\n",
				   (processor_id >> 20) & 15);
		}
		seq_printf(m, "CPU part\t: 0x%03x\n",
			   (processor_id >> 4) & 0xfff);
	}
	seq_printf(m, "CPU revision\t: %d\n", processor_id & 15);

	{
		unsigned int cache_info = read_cpuid(CPUID_CACHETYPE);
		if (cache_info != processor_id) {
			seq_printf(m, "Cache type\t: %s\n"
				      "Cache clean\t: %s\n"
				      "Cache lockdown\t: %s\n"
				      "Cache format\t: %s\n",
				   cache_types[CACHE_TYPE(cache_info)],
				   cache_clean[CACHE_TYPE(cache_info)],
				   cache_lockdown[CACHE_TYPE(cache_info)],
				   CACHE_S(cache_info) ? "Harvard" : "Unified");

			if (CACHE_S(cache_info)) {
				c_show_cache(m, "I", CACHE_ISIZE(cache_info));
				c_show_cache(m, "D", CACHE_DSIZE(cache_info));
			} else {
				c_show_cache(m, "Cache", CACHE_ISIZE(cache_info));
			}
		}
	}

	seq_puts(m, "\n");

	seq_printf(m, "Hardware\t: %s\n", machine_name);
	seq_printf(m, "Revision\t: %04x\n", system_rev);
	seq_printf(m, "Serial\t\t: %08x%08x\n",
		   system_serial_high, system_serial_low);

	return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	return *pos < 1 ? (void *)1 : NULL;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
	++*pos;
	return NULL;
}

static void c_stop(struct seq_file *m, void *v)
{
}

struct seq_operations cpuinfo_op = {
	.start	= c_start,
	.next	= c_next,
	.stop	= c_stop,
	.show	= c_show
};