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.set MULTIBOOT_MAGIC, 0x1badb002
.set MULTIBOOT_PAGE_ALIGN, 0x1
.set MULTIBOOT_MEMORY_INFO, 0x2
.set MULTIBOOT_VIDEO_MODE, 0x4
.set multiboot_flags, MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_VIDEO_MODE
.set multiboot_checksum, -(MULTIBOOT_MAGIC + multiboot_flags)
.section .multiboot
.align 4
.long MULTIBOOT_MAGIC
.long multiboot_flags
.long multiboot_checksum
/* for MULTIBOOT_MEMORY_INFO */
.long 0x00000000 /* header_addr */
.long 0x00000000 /* load_addr */
.long 0x00000000 /* load_end_addr */
.long 0x00000000 /* bss_end_addr */
.long 0x00000000 /* entry_addr */
/* for MULTIBOOT_VIDEO_MODE */
.long 0x00000000 /* mode_type */
.long 1280 /* width */
.long 1024 /* height */
.long 32 /* depth */
.section .stack, "aw", @nobits
stack_bottom:
.skip 32768
stack_top:
.section .text
.global start
.type start, @function
.extern init
.type init, @function
.extern multiboot_info_ptr
.type multiboot_info_ptr, @object
start:
cli
cld
mov $stack_top, %esp
and $-16, %esp
pushl %esp
pushl %eax /* Multiboot header magic */
pushl %ebx /* Multiboot header pointer */
mov %ebx, multiboot_info_ptr
call init
pushl $exit_message
call kprintf
cli
loop:
hlt
jmp loop
exit_message:
.asciz "Kernel exited."
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