panic dumps more registers, panic type arg

boot1.s

@@ -198,6 +198,12 @@ panic_simple:
 %endif
 
 
+%macro panic 1
+  push word %1
+  call panic_fancy
+%endmacro
+
+
 main:
   ; Set VGA mode
   ; https://mendelson.org/wpdos/videomodes.txt
@@ -216,14 +222,6 @@ main:
   mov ax, msg_boot1_loaded
   call vga_println
 
-  mov eax, 0xa1b2c3d4
-  mov ebx, 0x12345678
-  mov ecx, 0xdeadbeef
-  mov edx, 0xcafebabe
-  mov esi, 0xfeedface
-  mov edi, 0x66778899
-  call panic_fancy
-
   call test_a20
   test ax, ax
   jnz .a20_enabled
@@ -231,6 +229,14 @@ main:
   mov ax, msg_a20_disabled
   call vga_println
 
+  mov eax, 0xa1b2c3d4
+  mov ebx, 0x12345678
+  mov ecx, 0xdeadbeef
+  mov edx, 0xcafebabe
+  mov esi, 0xfeedface
+  mov edi, 0x66778899
+  panic PANIC_TYPE_A20
+
   ; TODO: enable a20
   hlt
 
@@ -243,48 +249,70 @@ main:
 
 ; Print a panic message then terminate.
 ; Arguments:
-; - [sp + 2]: panic message segment
-; - [sp]:     panic message offset
+; - word [sp]: panic type
 ; Does not return
 panic_fancy:
   push bp
   mov bp, sp
 
   ; Flags first so we don't cobber them when we sub (uwu)
-  pushfd     ; Temp flags: bp - 0x04
-  sub sp, 16 ; Buffer:     bp - 0x14
-  push eax   ; eax:        bp - 0x18
-  push ebx   ; ebx:        bp - 0x1c
-  push ecx   ; ecx:        bp - 0x20
-  push edx   ; edx:        bp - 0x24
-  push esi   ; esi:        bp - 0x28
-  push edi   ; edi:        bp - 0x2c
-  sub sp, 4  ; Flags:      bp - 0x30
-  mov eax, [bp - 0x04]
-  mov [bp - 0x30], eax
+  pushfd       ; Temp flags: bp - 0x04
+  sub sp, 16   ; Buffer:     bp - 0x14
+  push dword 0 ; Registers:  bp - 0x18
+  push eax
+  push ebx
+  push ecx
+  push edx
+  push esi
+  push edi
+  push esp
+  push ebp
+  xor eax, eax
+  mov ax, cs
+  push eax
+  mov ax, ds
+  push eax
+  mov ax, es
+  push eax
+  mov ax, fs
+  push eax
+  mov ax, gs
+  push eax
+  mov ax, ss
+  push eax
+  mov ax, word [bp - 0x04]
+  push eax
+
+  mov ax, [bp + 0x02]
+  mov [bp - 0x18], eax
 
   mov word [GLOBALS + VGA_COL], 0x4f00
   call vga_clear
 
-  mov ax, ss
-  mov es, ax
+  mov ax, VGA_WIDTH + 1
+  mov cx, msg_panic
+  mov dx, VGA_WIDTH - 1
+  call vga_print_raw
 
   xor bx, bx
-  mov di, VGA_WIDTH * 3
+  mov di, VGA_WIDTH * 4
 .loop_dump_regs:
-  cmp bx, 7
+  cmp bx, 16
   jae .loop_dump_regs_done
 
-  mov ax, bx
-  shl ax, 1
-  mov si, table_reg_msgs
-  add si, ax
+  mov si, bx
+  shl si, 1
+  add si, table_reg_msgs
   mov cx, [si]
   mov ax, di
   add ax, 1
-  mov dx, 6
+  mov dx, 3
   call vga_print_raw
 
+  push es
+  mov ax, ss
+  mov es, ax
+
   ; Format the current saved register value as hex
   lea si, [bp - 0x18]
   mov ax, bx
@@ -295,17 +323,35 @@ panic_fancy:
   call dump_reg
 
   mov ax, di
-  add ax, 7
+  add ax, 5
   lea cx, [bp - 0x14]
   mov dx, 8
   call vga_print_raw
-  
+
+  pop es
   inc bx
-  add di, VGA_WIDTH
+  add di, VGA_WIDTH / 5
   jmp .loop_dump_regs
   
 .loop_dump_regs_done:
+
+  mov bx, [bp + 0x04]
+  cmp bx, PANIC_TYPE_MAX
+  jae .print_panic_type_done
+  shl bx, 1
+  add bx, panic_type_msgs
+  mov cx, [bx]
+  mov ax, VGA_WIDTH * 2 + 1
+  mov dx, VGA_WIDTH - 1
+  call vga_print_raw
   
+.print_panic_type_done:
+
+  ; TODO: unwind stack
+  ; - Load saved bp and ip from [bp] and [bp + 2], respectively
+  ; - Load bp and ip before that from [prev_bp], [prev_bp + 2]
+  ; - Repeat
+
 .halt:
   hlt
   ; Handle non-maskable interrupts
@@ -597,24 +643,53 @@ msg_a20_enabled  db "a20 enabled", 0
 msg_a20_disabled db "a20 not enabled", 0
 msg_panic        db "panic!", 0
 
+msg_reg_eip   db "eip", 0
 msg_reg_eax   db "eax", 0
 msg_reg_ebx   db "ebx", 0
 msg_reg_ecx   db "ecx", 0
 msg_reg_edx   db "edx", 0
 msg_reg_esi   db "esi", 0
 msg_reg_edi   db "edi", 0
-msg_reg_flags db "flags", 0
+msg_reg_esp   db "esp", 0
+msg_reg_ebp   db "ebp", 0
+msg_reg_cs    db "cs", 0
+msg_reg_ds    db "ds", 0
+msg_reg_es    db "es", 0
+msg_reg_fs    db "fs", 0
+msg_reg_gs    db "gs", 0
+msg_reg_ss    db "ss", 0
+msg_reg_flags db "flg", 0
 
 table_reg_msgs:
+  dw msg_reg_eip
   dw msg_reg_eax
   dw msg_reg_ebx
   dw msg_reg_ecx
   dw msg_reg_edx
   dw msg_reg_esi
   dw msg_reg_edi
+  dw msg_reg_esp
+  dw msg_reg_ebp
+  dw msg_reg_cs
+  dw msg_reg_ds
+  dw msg_reg_es
+  dw msg_reg_fs
+  dw msg_reg_gs
+  dw msg_reg_ss
   dw msg_reg_flags
   dw 0
 
+msg_panic_generic db "generic panic", 0
+msg_panic_a20     db "failed to enable a20 line", 0
+
+panic_type_msgs:
+  PANIC_TYPE_GENERIC equ ($ - panic_type_msgs) / 2
+  dw msg_panic_generic
+  PANIC_TYPE_A20     equ ($ - panic_type_msgs) / 2
+  dw msg_panic_a20
+  PANIC_TYPE_MAX     equ ($ - panic_type_msgs) / 2
+  dw 0
+
 boot1_magic dd BOOT1_MAGIC
 
 BOOT1_TOTAL_LEN     equ $ - $$