BarinkOS/src/kernel/arch/i386/boot.S

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ArmAsm
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/*
* Multiboot
*/
.set ALIGN, 1<<0 /* align loaded modules on page boundaries */
.set MEMINFO, 1<<1 /* provide memory map */
.set FLAGS, ALIGN | MEMINFO /* this is the Multiboot 'flag' field */
.set MAGIC, 0x1BADB002 /* 'magic number' lets bootloader find the header */
.set CHECKSUM, -(MAGIC + FLAGS) /* checksum of above, to prove we are multiboot */
.section .multiboot
.align 4
.long MAGIC
.long FLAGS
.long CHECKSUM
.section .bss
.align 16
stack_bottom:
.skip 16384 # 16 KiB
stack_top:
.section .text
.include "./src/kernel/arch/i386/irs_table.s"
.include "./src/kernel/arch/i386/irq_table.s"
.include "./src/kernel/arch/i386/idt/idt.s"
.include "./src/kernel/arch/i386/paging.s"
.global _start
.type _start, @function
_start:
/*Setup the stack pointer to point to the beginning of our stack */
/* I believe its a high address growing down to lower adress for the stack on x86*/
mov $stack_top, %esp
/*Reset EFLAGS*/
pushl $0
popf
/* push the pointer to the Multiboot information structure*/
pushl %ebx
/* push the magic value */
pushl %eax
call early_main
cli
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.global load_gdt
load_gdt:
lgdt gdt
# set the segment selecters
movw $0x10, %ax
movw %ax, %ds
movw %ax, %es
movw %ax, %fs
movw %ax, %gs
movw %ax, %ss
ljmp $0x08, $flush
flush:
#load idt
call init_idt
sti
# Try enable A20
# mov $0x2401, %ax
# int $0x15
# enable protected mode
mov %cr0, %eax
or $1, %eax
mov %eax, %cr0
call kernel_main
cli
1: hlt
jmp 1b
.include "./src/kernel/arch/i386/gdt/gdt.s"