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/*
* prepare to run common code
*
* Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/percpu.h>
#include <linux/start_kernel.h>
#include <asm/processor.h>
#include <asm/proto.h>
#include <asm/smp.h>
#include <asm/setup.h>
#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/kdebug.h>
#include <asm/e820.h>
static void __init zap_identity_mappings(void)
{
pgd_t *pgd = pgd_offset_k(0UL);
pgd_clear(pgd);
__flush_tlb_all();
}
/* Don't add a printk in there. printk relies on the PDA which is not initialized
yet. */
static void __init clear_bss(void)
{
memset(__bss_start, 0,
(unsigned long) __bss_stop - (unsigned long) __bss_start);
}
static void __init copy_bootdata(char *real_mode_data)
{
char * command_line;
memcpy(&boot_params, real_mode_data, sizeof boot_params);
if (boot_params.hdr.cmd_line_ptr) {
command_line = __va(boot_params.hdr.cmd_line_ptr);
memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
}
}
#define EBDA_ADDR_POINTER 0x40E
static __init void reserve_ebda(void)
{
unsigned ebda_addr, ebda_size;
/*
* 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;
if (!ebda_addr)
return;
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;
reserve_early(ebda_addr, ebda_addr + ebda_size, "EBDA");
}
void __init x86_64_start_kernel(char * real_mode_data)
{
int i;
/*
* Build-time sanity checks on the kernel image and module
* area mappings. (these are purely build-time and produce no code)
*/
BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START);
BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE);
BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0);
BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
(__START_KERNEL & PGDIR_MASK)));
/* clear bss before set_intr_gate with early_idt_handler */
clear_bss();
/* Make NULL pointers segfault */
zap_identity_mappings();
/* Cleanup the over mapped high alias */
cleanup_highmap();
for (i = 0; i < IDT_ENTRIES; i++) {
#ifdef CONFIG_EARLY_PRINTK
set_intr_gate(i, &early_idt_handlers[i]);
#else
set_intr_gate(i, early_idt_handler);
#endif
}
load_idt((const struct desc_ptr *)&idt_descr);
early_printk("Kernel alive\n");
for (i = 0; i < NR_CPUS; i++)
cpu_pda(i) = &boot_cpu_pda[i];
pda_init(0);
copy_bootdata(__va(real_mode_data));
reserve_early(__pa_symbol(&_text), __pa_symbol(&_end), "TEXT DATA BSS");
/* Reserve 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;
reserve_early(ramdisk_image, ramdisk_end, "RAMDISK");
}
reserve_ebda();
/*
* At this point everything still needed from the boot loader
* or BIOS or kernel text should be early reserved or marked not
* RAM in e820. All other memory is free game.
*/
start_kernel();
}
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