update qemu study

2025-12-30 08:19:49 +00:00
parent ac241a9148
commit 8f1a81b699
11 changed files with 885 additions and 0 deletions
@@ -0,0 +1,152 @@
+; mybios_ssh.asm
+[BITS 16]
+[ORG 0]
+
+bios_start:
+    ; 1. 세그먼트 초기화
+    mov ax, 0xF000
+    mov ds, ax
+    mov es, ax
+    xor ax, ax
+    mov ss, ax
+    mov sp, 0x7C00
+
+    ; 2. 시리얼 포트 초기화 (가장 중요!)
+    call init_serial
+
+    ; 3. 부팅 메시지 출력
+    mov si, msg_boot
+    call print_serial
+
+    ; 4. 메인 루프 (입력 대기)
+    mov si, msg_menu
+    call print_serial
+
+main_loop:
+    ; --- Heartbeat (살아있음을 표시) ---
+    ; 입력이 없어도 멈춘 게 아니라는 걸 보여주기 위해 점(.)을 찍을 수도 있지만,
+    ; 너무 지저분해지니 생략하고 입력만 기다립니다.
+
+    ; [입력 확인] 0x3FD 포트의 0번 비트가 1이면 데이터가 온 것임
+    mov dx, 0x3FD
+    in al, dx
+    test al, 1
+    jz main_loop        ; 데이터 없으면 계속 뺑뺑이(Loop)
+
+    ; [데이터 읽기] 0x3F8 포트에서 읽음
+    mov dx, 0x3F8
+    in al, dx
+
+    ; [내가 누른 키 화면에 보여주기 (Echo)]
+    ; 이게 없으면 내가 뭘 눌렀는지 터미널에 안 보임!
+    out dx, al          
+
+    ; [키 판별]
+    cmp al, '1'
+    je action_shutdown
+    
+    cmp al, '2'
+    je action_reboot
+
+    jmp main_loop
+
+; ===========================================================
+; [Actions]
+; ===========================================================
+
+action_shutdown:
+    mov si, msg_bye
+    call print_serial
+
+    ; PIIX4 ACPI Shutdown (Power Off)
+    ; 1. I/O Enable
+    mov dx, 0xCF8
+    mov eax, 0x80000B04
+    out dx, eax
+    mov dx, 0xCFC
+    mov eax, 0x0001
+    out dx, eax
+
+    ; 2. PMBA -> 0xB000
+    mov dx, 0xCF8
+    mov eax, 0x80000B40
+    out dx, eax
+    mov dx, 0xCFC
+    mov eax, 0x0000B001
+    out dx, eax
+
+    ; 3. ACPI Enable
+    mov dx, 0xCF8
+    mov eax, 0x80000B80
+    out dx, eax
+    mov dx, 0xCFC
+    mov eax, 0x00000001
+    out dx, eax
+
+    ; 4. Shutdown Command
+    mov dx, 0xB004
+    mov ax, 0x2000
+    out dx, ax
+    
+    ; 안 꺼지면 대기
+    hlt
+    jmp $
+
+action_reboot:
+    mov si, msg_reboot
+    call print_serial
+    
+    ; Reboot Command
+    mov dx, 0x64
+    mov al, 0xFE
+    out dx, al
+    hlt
+    jmp $
+
+; ===========================================================
+; [Drivers]
+; ===========================================================
+init_serial:
+    mov dx, 0x3FB
+    mov al, 0x80    ; DLAB ON
+    out dx, al
+    mov dx, 0x3F8
+    mov al, 0x0C    ; 9600 baud
+    out dx, al
+    mov dx, 0x3F9
+    mov al, 0x00
+    out dx, al
+    mov dx, 0x3FB
+    mov al, 0x03    ; 8N1, DLAB OFF
+    out dx, al
+    ret
+
+print_serial:
+    mov dx, 0x3F8
+.loop:
+    lodsb
+    cmp al, 0
+    je .done
+    out dx, al
+    jmp .loop
+.done:
+    ret
+
+; ===========================================================
+; [Data]
+; ===========================================================
+; 줄바꿈(0x0D, 0x0A)을 명확히 넣었습니다.
+msg_boot    db 0x0D, 0x0A, "===============================", 0x0D, 0x0A
+            db "   SSH Serial BIOS v1.0        ", 0x0D, 0x0A
+            db "===============================", 0x0D, 0x0A, 0
+
+msg_menu    db 0x0D, 0x0A, "COMMANDS: [1] Shutdown  [2] Reboot", 0x0D, 0x0A
+            db "Input > ", 0
+
+msg_bye     db 0x0D, 0x0A, ">>> System is HALTING...", 0x0D, 0x0A, 0
+msg_reboot  db 0x0D, 0x0A, ">>> REBOOTING...", 0x0D, 0x0A, 0
+
+times 65520-($-$$) db 0 
+reset_vector:
+    jmp 0xF000:0x0000
+    times 16-($-reset_vector) db 0