setup_64.c

linux 内核源代码

/*
 *  Copyright (C) 1995  Linus Torvalds
 */

/*
 * This file handles the architecture-dependent parts of initialization
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/screen_info.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/highmem.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <asm/processor.h>
#include <linux/console.h>
#include <linux/seq_file.h>
#include <linux/crash_dump.h>
#include <linux/root_dev.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/kallsyms.h>
#include <linux/edd.h>
#include <linux/mmzone.h>
#include <linux/kexec.h>
#include <linux/cpufreq.h>
#include <linux/dmi.h>
#include <linux/dma-mapping.h>
#include <linux/ctype.h>

#include <asm/mtrr.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/msr.h>
#include <asm/desc.h>
#include <video/edid.h>
#include <asm/e820.h>
#include <asm/dma.h>
#include <asm/mpspec.h>
#include <asm/mmu_context.h>
#include <asm/proto.h>
#include <asm/setup.h>
#include <asm/mach_apic.h>
#include <asm/numa.h>
#include <asm/sections.h>
#include <asm/dmi.h>
#include <asm/cacheflush.h>

/*
 * Machine setup..
 */

struct cpuinfo_x86 boot_cpu_data __read_mostly;
EXPORT_SYMBOL(boot_cpu_data);

unsigned long mmu_cr4_features;

/* Boot loader ID as an integer, for the benefit of proc_dointvec */
int bootloader_type;

unsigned long saved_video_mode;

int force_mwait __cpuinitdata;

/* 
 * Early DMI memory
 */
int dmi_alloc_index;
char dmi_alloc_data[DMI_MAX_DATA];

/*
 * Setup options
 */
struct screen_info screen_info;
EXPORT_SYMBOL(screen_info);
struct sys_desc_table_struct {
	unsigned short length;
	unsigned char table[0];
};

struct edid_info edid_info;
EXPORT_SYMBOL_GPL(edid_info);

extern int root_mountflags;

char __initdata command_line[COMMAND_LINE_SIZE];

struct resource standard_io_resources[] = {
	{ .name = "dma1", .start = 0x00, .end = 0x1f,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "pic1", .start = 0x20, .end = 0x21,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "timer0", .start = 0x40, .end = 0x43,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "timer1", .start = 0x50, .end = 0x53,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "keyboard", .start = 0x60, .end = 0x6f,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
	{ .name = "fpu", .start = 0xf0, .end = 0xff,
		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
};

#define IORESOURCE_RAM (IORESOURCE_BUSY | IORESOURCE_MEM)

struct resource data_resource = {
	.name = "Kernel data",
	.start = 0,
	.end = 0,
	.flags = IORESOURCE_RAM,
};
struct resource code_resource = {
	.name = "Kernel code",
	.start = 0,
	.end = 0,
	.flags = IORESOURCE_RAM,
};
struct resource bss_resource = {
	.name = "Kernel bss",
	.start = 0,
	.end = 0,
	.flags = IORESOURCE_RAM,
};

#ifdef CONFIG_PROC_VMCORE
/* elfcorehdr= specifies the location of elf core header
 * stored by the crashed kernel. This option will be passed
 * by kexec loader to the capture kernel.
 */
static int __init setup_elfcorehdr(char *arg)
{
	char *end;
	if (!arg)
		return -EINVAL;
	elfcorehdr_addr = memparse(arg, &end);
	return end > arg ? 0 : -EINVAL;
}
early_param("elfcorehdr", setup_elfcorehdr);
#endif

#ifndef CONFIG_NUMA
static void __init
contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
{
	unsigned long bootmap_size, bootmap;

	bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
	bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size);
	if (bootmap == -1L)
		panic("Cannot find bootmem map of size %ld\n",bootmap_size);
	bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, end_pfn);
	e820_register_active_regions(0, start_pfn, end_pfn);
	free_bootmem_with_active_regions(0, end_pfn);
	reserve_bootmem(bootmap, bootmap_size);
} 
#endif

#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
struct edd edd;
#ifdef CONFIG_EDD_MODULE
EXPORT_SYMBOL(edd);
#endif
/**
 * copy_edd() - Copy the BIOS EDD information
 *              from boot_params into a safe place.
 *
 */
static inline void copy_edd(void)
{
     memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
	    sizeof(edd.mbr_signature));
     memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
     edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
     edd.edd_info_nr = boot_params.eddbuf_entries;
}
#else
static inline void copy_edd(void)
{
}
#endif

#ifdef CONFIG_KEXEC
static void __init reserve_crashkernel(void)
{
	unsigned long long free_mem;
	unsigned long long crash_size, crash_base;
	int ret;

	free_mem = ((unsigned long long)max_low_pfn - min_low_pfn) << PAGE_SHIFT;

	ret = parse_crashkernel(boot_command_line, free_mem,
			&crash_size, &crash_base);
	if (ret == 0 && crash_size) {
		if (crash_base > 0) {
			printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
					"for crashkernel (System RAM: %ldMB)\n",
					(unsigned long)(crash_size >> 20),
					(unsigned long)(crash_base >> 20),
					(unsigned long)(free_mem >> 20));
			crashk_res.start = crash_base;
			crashk_res.end   = crash_base + crash_size - 1;
			reserve_bootmem(crash_base, crash_size);
		} else
			printk(KERN_INFO "crashkernel reservation failed - "
					"you have to specify a base address\n");
	}
}
#else
static inline void __init reserve_crashkernel(void)
{}
#endif

#define EBDA_ADDR_POINTER 0x40E

unsigned __initdata ebda_addr;
unsigned __initdata ebda_size;

static void discover_ebda(void)
{
	/*
	 * there is a real-mode segmented pointer pointing to the 
	 * 4K EBDA area at 0x40E
	 */
	ebda_addr = *(unsigned short *)__va(EBDA_ADDR_POINTER);
	ebda_addr <<= 4;

	ebda_size = *(unsigned short *)__va(ebda_addr);

	/* Round EBDA up to pages */
	if (ebda_size == 0)
		ebda_size = 1;
	ebda_size <<= 10;
	ebda_size = round_up(ebda_size + (ebda_addr & ~PAGE_MASK), PAGE_SIZE);
	if (ebda_size > 64*1024)
		ebda_size = 64*1024;
}

void __init setup_arch(char **cmdline_p)
{
	printk(KERN_INFO "Command line: %s\n", boot_command_line);

	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
	screen_info = boot_params.screen_info;
	edid_info = boot_params.edid_info;
	saved_video_mode = boot_params.hdr.vid_mode;
	bootloader_type = boot_params.hdr.type_of_loader;

#ifdef CONFIG_BLK_DEV_RAM
	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
#endif
	setup_memory_region();
	copy_edd();

	if (!boot_params.hdr.root_flags)
		root_mountflags &= ~MS_RDONLY;
	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;

	code_resource.start = virt_to_phys(&_text);
	code_resource.end = virt_to_phys(&_etext)-1;
	data_resource.start = virt_to_phys(&_etext);
	data_resource.end = virt_to_phys(&_edata)-1;
	bss_resource.start = virt_to_phys(&__bss_start);
	bss_resource.end = virt_to_phys(&__bss_stop)-1;

	early_identify_cpu(&boot_cpu_data);

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

	parse_early_param();

	finish_e820_parsing();

	e820_register_active_regions(0, 0, -1UL);
	/*
	 * partially used pages are not usable - thus
	 * we are rounding upwards:
	 */
	end_pfn = e820_end_of_ram();
	num_physpages = end_pfn;

	check_efer();

	discover_ebda();

	init_memory_mapping(0, (end_pfn_map << PAGE_SHIFT));

	dmi_scan_machine();

#ifdef CONFIG_SMP
	/* setup to use the static apicid table during kernel startup */
	x86_cpu_to_apicid_ptr = (void *)&x86_cpu_to_apicid_init;
#endif

#ifdef CONFIG_ACPI
	/*
	 * Initialize the ACPI boot-time table parser (gets the RSDP and SDT).
	 * Call this early for SRAT node setup.
	 */
	acpi_boot_table_init();
#endif

	/* How many end-of-memory variables you have, grandma! */
	max_low_pfn = end_pfn;
	max_pfn = end_pfn;
	high_memory = (void *)__va(end_pfn * PAGE_SIZE - 1) + 1;

	/* Remove active ranges so rediscovery with NUMA-awareness happens */
	remove_all_active_ranges();

#ifdef CONFIG_ACPI_NUMA
	/*
	 * Parse SRAT to discover nodes.
	 */
	acpi_numa_init();
#endif

#ifdef CONFIG_NUMA
	numa_initmem_init(0, end_pfn); 
#else
	contig_initmem_init(0, end_pfn);
#endif

	/* Reserve direct mapping */
	reserve_bootmem_generic(table_start << PAGE_SHIFT, 
				(table_end - table_start) << PAGE_SHIFT);

	/* reserve kernel */
	reserve_bootmem_generic(__pa_symbol(&_text),
				__pa_symbol(&_end) - __pa_symbol(&_text));

	/*
	 * reserve physical page 0 - it's a special BIOS page on many boxes,
	 * enabling clean reboots, SMP operation, laptop functions.
	 */
	reserve_bootmem_generic(0, PAGE_SIZE);

	/* reserve ebda region */
	if (ebda_addr)
		reserve_bootmem_generic(ebda_addr, ebda_size);
#ifdef CONFIG_NUMA
	/* reserve nodemap region */
	if (nodemap_addr)
		reserve_bootmem_generic(nodemap_addr, nodemap_size);
#endif

#ifdef CONFIG_SMP
	/* Reserve SMP trampoline */
	reserve_bootmem_generic(SMP_TRAMPOLINE_BASE, 2*PAGE_SIZE);
#endif

#ifdef CONFIG_ACPI_SLEEP
       /*
        * Reserve low memory region for sleep support.
        */
       acpi_reserve_bootmem();
#endif
	/*
	 * Find and reserve possible boot-time SMP configuration:
	 */
	find_smp_config();
#ifdef CONFIG_BLK_DEV_INITRD
	if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
		unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
		unsigned long ramdisk_size  = boot_params.hdr.ramdisk_size;
		unsigned long ramdisk_end   = ramdisk_image + ramdisk_size;
		unsigned long end_of_mem    = end_pfn << PAGE_SHIFT;

		if (ramdisk_end <= end_of_mem) {
			reserve_bootmem_generic(ramdisk_image, ramdisk_size);
			initrd_start = ramdisk_image + PAGE_OFFSET;
			initrd_end = initrd_start+ramdisk_size;
		} else {
			printk(KERN_ERR "initrd extends beyond end of memory "