From d8a43e068895fb6e858377ea9c79aaa3e920476e Mon Sep 17 00:00:00 2001
From: Adrien Bourmault <neox@os-k.eu>
Date: Tue, 12 Feb 2019 14:58:26 +0100
Subject: [PATCH] multiboot stuff '-'

---
 boot/loader/loader.asm | 46 +++++++++++++++++++++++++++++++-----------
 1 file changed, 34 insertions(+), 12 deletions(-)

diff --git a/boot/loader/loader.asm b/boot/loader/loader.asm
index 6734aec..583e121 100644
--- a/boot/loader/loader.asm
+++ b/boot/loader/loader.asm
@@ -25,16 +25,40 @@
 
 %define DEBUG
 
-[BITS 16]
-[ORG 0x1000]
+[BITS 32]
+[global _start]
+[ORG 0x100000]                                  ; Where GRUB loads us.
 
-mov ax, cs                                  ; correcting cs after the horrible far jump
-mov ds, ax                                  ; hm... And ds too
-mov es, ax                                  ; And es because it is jealous
+%include "boot/loader/multiboot.inc"
 
-mov [Bootdrv], dl
-xor dl, dl
-jmp 0x0000:main
+_start:
+    mov ax, cs                                  ; correcting cs after the horrible far jump
+    mov ds, ax                                  ; hm... And ds too
+    mov es, ax                                  ; And es because it is jealous
+
+    mov [Bootdrv], dl
+    xor dl, dl
+    jmp 0x0000:main ;; pas sûr
+
+[align 4]
+dd MULTIBOOT_HEADER_MAGIC
+dd MULTIBOOT_HEADER_FLAGS
+dd CHECKSUM
+dd multiboot_header                             ; Header address
+dd _start                                       ; Address of code entry point
+dd 00                                           ; (end of code) not necessary
+dd 00                                           ; (bss) not necessary
+dd MB_start                                     ; entry address GRUB will start at
+
+MB_start:
+    mov esp, KERNEL_STACK                       ; Setup the stack
+    push 0                                      ; Reset EFLAGS
+    popf
+    push eax                                    ; 2nd argument is magic number
+    push ebx                                    ; 1st argument multiboot info pointer
+    call main
+    add esp, 8                                  ; Cleanup 8 bytes pushed as arguments
+    jmp Die
 
 %include "boot/loader/cpu/cpuid.asm"
 %include "boot/loader/io/rmterm.asm"
@@ -42,6 +66,8 @@ jmp 0x0000:main
 
 main:
 
+    ;; XXX NEED TO SWITCH TO RM HERE ;;
+
     ;; compatibility check
     push si
     mov si, Init
@@ -92,10 +118,6 @@ main:
     push dword [VGA_HEIGHT]
     jmp (CODE_SELECTOR-GDT64):main32
 
-;; THE HOLE ----------------------------------------------------------------- ;;
-ErrorNo64:
-    mov si, NoLongMode
-    call PrintB
 Die:
     cli
     hlt                                     ; die nooooow