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#include <arch/asm.h>
#include <arch/intel.h>
.section ".text"
.code32
.globl _start
_start:
cli
lgdt %cs:gdtaddr
ljmp $0x10, $1f
1: movl $0x18, %eax
movl %eax, %ds
movl %eax, %es
movl %eax, %ss
movl %eax, %fs
movl %eax, %gs
intel_chip_post_macro(0x13) /* post 12 */
/** clear stack */
leal _stack, %edi
movl $_estack, %ecx
subl %edi, %ecx
xorl %eax, %eax
rep
stosb
/** clear bss */
leal _bss, %edi
movl $_ebss, %ecx
subl %edi, %ecx
jz .Lnobss
xorl %eax, %eax
rep
stosb
.Lnobss:
/* set new stack */
movl $_estack, %esp
/* Push the cpu index and struct cpu */
pushl $0
pushl $0
/* push the boot_complete flag */
pushl %ebp
/* Save the stack location */
movl %esp, %ebp
/*
* Now we are finished. Memory is up, data is copied and
* bss is cleared. Now we call the main routine and
* let it do the rest.
*/
intel_chip_post_macro(0xfe) /* post fe */
/* Restore the stack location */
movl %ebp, %esp
/* The boot_complete flag has already been pushed */
call hardwaremain
/*NOTREACHED*/
.Lhlt:
intel_chip_post_macro(0xee) /* post fe */
hlt
jmp .Lhlt
.globl gdt, gdt_end, gdt_limit
gdt_limit = gdt_end - gdt - 1 /* compute the table limit */
gdtaddr:
.word gdt_limit
.long gdt /* we know the offset */
gdt:
// selgdt 0
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
// selgdt 8
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
// selgdt 0x10
/* flat code segment */
.word 0xffff, 0x0000
.byte 0x00, 0x9b, 0xcf, 0x00
//selgdt 0x18
/* flat data segment */
.word 0xffff, 0x0000
.byte 0x00, 0x93, 0xcf, 0x00
//selgdt 0x20
.word 0x0000, 0x0000 /* dummy */
.byte 0x00, 0x00, 0x00, 0x00
#if defined(CONFIG_LEGACY_VGABIOS) && (CONFIG_LEGACY_VGABIOS == 1)
// from monty:
/* 0x00009a00,0000ffffULL, 20h: 16-bit 64k code at 0x00000000 */
/* 0x00009200,0000ffffULL 28h: 16-bit 64k data at 0x00000000 */
// selgdt 0x28
/*16-bit 64k code at 0x00000000 */
.word 0xffff, 0x0000
.byte 0, 0x9a, 0, 0
// selgdt 0x30
/*16-bit 64k data at 0x00000000 */
.word 0xffff, 0x0000
.byte 0, 0x92, 0, 0
#endif // defined(CONFIG_VGABIOS) && (CONFIG_VGABIOS == 1)
gdt_end:
.code32
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