128 lines
2.9 KiB
C
128 lines
2.9 KiB
C
/*
|
|
* 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();
|
|
}
|
|
|
|
/* 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);
|
|
}
|
|
|
|
void __init x86_64_start_kernel(char * real_mode_data)
|
|
{
|
|
int i;
|
|
|
|
/* clear bss before set_intr_gate with early_idt_handler */
|
|
clear_bss();
|
|
|
|
/* Make NULL pointers segfault */
|
|
zap_identity_mappings();
|
|
|
|
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));
|
|
|
|
/* 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);
|
|
}
|
|
|
|
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();
|
|
}
|