Enough for today

2 files changed, 60 insertions, 31 deletions

diff --git a/src/boot/boot.stage1.asm b/src/boot/boot.stage1.asm
index 5fa3b7a..70e2f17 100644
--- a/src/boot/boot.stage1.asm
+++ b/src/boot/boot.stage1.asm
@@ -5,13 +5,19 @@
 
     %include "boot.common.asm"
 
-    %define READ_SECTORS_NUM 1
-    %define BOOT_LOAD_ADDR 0x7c00
+    %define LOAD_ADDRESS 0x7C00     
+    %define STAGE2_ADDRESS 0x7E00
+    %define RELOCATE_ADDRESS 0x0600
     %define SECTOR_SIZE 512
+    %define OFFSET_RELOC (RELOCATE_ADDRESS - LOAD_ADDRESS) 
+    %define STAGE2_SECTORS 8
+
 
     global _start
 
 _start: 
+    jmp 0x0000:.setup_segments
+    .setup_segments:
     ;; Disable interrupts
     cli                         
 
@@ -20,44 +26,65 @@ _start:
     mov ds, ax
     mov es, ax  
     mov ss, ax
+    mov gs, ax
 
-    ;; Adjust Stack
-    mov sp, _start
-    
-    clc
+    mov sp, LOAD_ADDRESS        ; Adjust stack
 
-    mov [drive], dl
-    mov si, disk_addr_packet
-    mov ah, 0x42                ; BIOS extended read function
-    mov dl, [drive]             ; Drive number
-    int 0x13                    ; BIOS disk services
-    jc _disk_read_err
-    
-    mov si, disk_read_success_msg
-    call _print_string
+    ;;  Save disk
+    mov [drive], dl             ; Get drive ID from BIOS
 
-    jmp 0x0000:0x7e00
+    sti
+    
+    mov si, LOAD_ADDRESS
+    mov di, RELOCATE_ADDRESS
+    mov cx, SECTOR_SIZE
+    cld
+    rep movsdb
+    
+    jmp 0x0000:(next)
+_read_disk_real_mode:
+    .start:
+    cmp cx, 127
+    jbe .good_size  
+    pusha
+    mov cx, 127
+    call _read_disk_real_mode
+    popa
+    add eax, 127
+    add dx, 127*512/16
+    sub cx, 127
+    jmp .start
 
-_disk_read_err: 
+    .good_size:
+    mov [DAP.LBA_lower], ax
+    mov [DAP.num_sectors], cx
+    mov [DAP.buf_segment], dx
+    mov [DAP.buf_offset], bx
+    mov dl, [disk]
+    mov si, DAP
+    mov ah, 0x42
+    int 0x13
+    jc .disk_read_err
+    ret
+    .disk_read_err:
     mov si, disk_read_err_msg
     call _print_string
-
-    hlt
-    jmp _disk_read_err
+    .halt: hlt
+    jmp .halt
 
 _print_string:  
     pusha
     mov ah, 0x0e
     mov bh, 0x00
 
-.print_loop:     
+    .print_loop:     
     lodsb
     test al, al
 	je .print_return
     int 0x10
 	jmp .print_loop
 
-.print_return:
+    .print_return:
 	popa
 	ret
 
@@ -68,14 +95,17 @@ _end:
 drive:   db 0
 disk_read_err_msg: db "Failed to read disk", 13, 10, 0
 disk_read_success_msg: db "Read the disk successfully", 13, 10, 0
-disk_addr_packet:  
-	db 0x10
-	db 0x00
-	dw READ_SECTORS_NUM
-	dw 0x7e00
-	dw 0x0000
-	dq 1
+boot_msg:  db "Booting", 13, 10, 0
+DAP:    
+    db 0x10     
+    db 0
+    .num_sectors: dw 127
+    .buf_offset: dw 0x0
+    .buf_segment: dw 0x0
+    .LBA_lower: dd 0x0
+    .LBA_upper: dd 0x0
 
+    
 	;; Padding and magic number
 	times 510 - ($ - $$) db 0
 	dw 0xaa55
diff --git a/src/boot/boot.stage2.asm b/src/boot/boot.stage2.asm
index 8f4885b..97a2d05 100644
--- a/src/boot/boot.stage2.asm
+++ b/src/boot/boot.stage2.asm
@@ -1,7 +1,7 @@
     ;; boot.stage2.asm
 
     [bits 16]
-    [org 0x7e00]
+    [org 0x0000]
 
     %include "boot.stage2.a20.asm"
     %include "boot.stage2.pm.asm"
@@ -11,4 +11,3 @@ _s2_entry:
     call _enable_a20
     call _enable_pm
     [bits 32]
-