StupidOS/kernel/boot/head.s

70 lines
1.2 KiB
ArmAsm

;; File: head.s
[BITS 32]
%include "machdep.inc"
%include "sys/multiboot.inc"
%include "sys/i386/registers.inc"
%include "sys/i386/mmu.inc"
;; Define: MB_HDR_FLAGS
MB_HDR_FLAGS equ MB_HDR_ALIGN | MB_HDR_MEMINFO | MB_HDR_VIDEO
section .multiboot.data
align 4
istruc mb_header
at mb_header.magic, dd MB_HDR_MAGIC
at mb_header.flags, dd MB_HDR_FLAGS
at mb_header.checksum, dd -(MB_HDR_MAGIC + MB_HDR_FLAGS)
; video mode info
at mb_header.mode_type, dd 0
at mb_header.width, dd 1024
at mb_header.height, dd 768
at mb_header.depth, dd 32
iend
section .multiboot.text
;; Function: entry
;;
;;
;; in:
;; EAX - Multiboot magic
;; EBX - Multiboot structure
;;
;; out:
;; none
;;
global entry
entry:
extern stack_top
mov esp, V2P(stack_top)
;; save boot params
mov edi, eax
mov esi, ebx
extern feat_detect
call feat_detect
;; setup 4MB paging
;; TODO: check if 4MB paging is available
mov eax, cr4
or eax, CR4_PSE
mov cr4, eax
extern page_directory
mov eax, V2P(page_directory)
mov cr3, eax
;; enable paging
mov eax, cr0
or eax, CR0_PG | CR0_PE | CR0_WP
mov cr0, eax
extern page_directory
mov eax, page_directory - KERNBASE
extern kernel_start
mov ebx, kernel_start