From 56f01a0888af19b6543506d73381f32e75e426e2 Mon Sep 17 00:00:00 2001
From: Ain <41307858+nero@users.noreply.github.com>
Date: Wed, 13 Mar 2019 17:28:38 +0000
Subject: [PATCH] Remove memory/mcb management

---
 main.asm |  15 ++--
 mem.asm  | 237 -------------------------------------------------------
 2 files changed, 7 insertions(+), 245 deletions(-)
 delete mode 100644 mem.asm

diff --git a/main.asm b/main.asm
index b6debfe..5ddfc08 100644
--- a/main.asm
+++ b/main.asm
@@ -3,15 +3,14 @@ cpu 8086
 org 0x0100
 jmp main
 
+str1:
+  db "Hello!", 0
+
 main:
-  mov ax,0x1000
-  mov bx,0x0000
-  mov cx,0x0800
-  call mtab_set
-  call mtab_dump
+  mov ax,cs
+  mov ds,ax
+  mov si,str1
+  call kprintf
   ret
 
 %include "kprintf.asm"
-
-; mem MUST be last because it will write after itself
-%include "mem.asm"
diff --git a/mem.asm b/mem.asm
deleted file mode 100644
index 8d03ae6..0000000
--- a/mem.asm
+++ /dev/null
@@ -1,237 +0,0 @@
-; memory type is enum
-;  00 - free
-;  01 - unknown
-;  02 - allocated by us
-;  03 - reserved, like BIOS code or tables for the cpu
-;  04 - unusable
-
-; return the addr of the mtab
-; out: es:bx
-mtab_ref:
-  push cs
-  pop es
-  mov bx,mtab
-  ret
-
-; finds a place for a new item in the mm table
-; this detects 'empty' slots by the size field being zero
-; in:	ds:si:	pointer to first mtab item
-; out:	bx:	offset for empty slot
-mtab_alloc:
-  push ax
-  call mtab_ref
-.loop:
-  cmp WORD [es:bx],0x0000
-  je .end
-  add bx,0x0010
-  jmp .loop
-.end:
-  pop ax
-  ret
-
-; splits a mtab item at offset
-; in:  ds:si: pointer mtab item
-;      ax:    split position in 16 byte blocks
-; out: ds:si: pointer to lower half
-;      ds:di: pointer to upper half
-mtab_split:
-  push cx ; remaining memory block length
-  mov cx,[ds:si]
-
-  mov [ds:si],ax ; this resizes the first item
-  sub cx, ax
-
-  push bx
-  call mtab_alloc
-  mov di,bx
-  pop bx
-
-  push si ; backup because movsw increments them
-  push di ; ^
-  push cx ; counter for movsb
-  mov es,ds
-  mov cx,0x08 ; 8 words = 16 bytes
-  rep movsw ; repeat cx times
-  pop cx
-  pop di
-  pop si
-
-  mov [ds:di],cx
-
-  pop cx
-  ret
-
-; in:  ax: segment
-;      bh: task id (0 for non-task memory)
-;      bl: memory type (see enum at top of file)
-;      cx: number of 16-byte blocks
-mtab_set:
-  push ds
-  push cx ; length of current item
-  push dx ; cumulative position
-  push bx ; pointer to mtab item
-
-  call mtab_ref
-  mov dx,0x0000
-  push bx ; use as iterator, restoring base value afterwards
-.findbase: ; we pick the mtab item where our segment lies in
-  mov cx,[es:bx]
-  add dx,cx
-  cmp dx,ax
-  jnbe .dupbase
-  add bx,0x0010
-  jmp .findbase
-.dupbase: ; we duplicate it, so we potentially have one after and one before our new item
-  mov si,bx
-  call mtab_alloc
-  mov di,bx
-  pop bx
-
-  push si ; backup because movsw increments them
-  push di ; ^
-  push cx ; counter for movsb
-  mov cx,0x08 ; a mtab item is 8 words = 16 bytes
-  push es
-  pop ds
-  rep movsw
-  pop cx
-  pop di
-  pop si
-.resizebase1:
-  push ax ; size = [Segment ax] - ([End addr dx] - [Length cx])
-  sub ax,dx
-  add ax,cx
-  mov [si],ax
-  pop ax
-.resizebase2:
-  push dx
-  sub dx,ax
-  mov [di],dx
-  pop dx
-.insert:
-  push bx
-  call mtab_alloc
-  mov dx,bx
-  pop bx
-.base1_link:
-  push ax
-  mov ax,dx
-  sub ax,bx ; addr are relative to mtab start
-  mov [si+02],ax
-  pop ax
-.new_link:
-  push ax
-  mov ax,di
-  sub ax,bx ; addr are relative to mtab start
-  mov di,dx
-  mov [di+02],ax
-  pop ax
-
-  pop bx
-  mov [di+04],bx
-
-  pop dx
-  pop cx
-
-  pop ds
-  ret
-
-mtab_dump:
-  push cs
-  pop ds
-  mov cx,0x0000
-  mov bp,mtab
-  mov si,0x0000
-
-.loop:
-  push si
-
-  mov ax, bp
-  add ax, si
-  add ax, 0x06
-  push ax
-
-  mov al,[bp+si+0x05]
-  push ax ; task id
-
-  mov al,[bp+si+0x04]
-  push bp
-  push si
-  mov bp,.typechar
-  and ax,0x00FF
-  mov si,ax
-  mov al,[bp+si]
-  pop si
-  pop bp
-  push ax ; memory type
-
-  mov bx,cx
-  add cx,[bp+si+0x00]
-  mov ax,cx
-  dec ax
-  push ax ; end addr
-  push bx ; start addr
-
-  mov si,.linefmt
-  call kprintf
-
-  pop ax
-  pop ax
-  pop ax
-  pop ax
-  pop ax
-  pop si
-
-  ; look for next line
-  mov ax,[bp+si+0x02]
-  test ax,0xFFFF
-  mov si,ax
-  jnz .loop
-  ret
-.linefmt:
-  db "%X0 %XF %c %x %s", 0
-.typechar:
-  db "F?ARU", 0
-
-; pre-filled table for memory management
-align 16
-mtab:
-  ; interrupt vector table
-  dw 0x0040
-  dw 0x0010
-  db 3
-  db 0
-  db "IVT", 0
-align 16
-  ; bios data area (writes here during runtime)
-  dw 0x0010
-  dw 0x0020
-  db 3
-  db 0
-  db "BDA", 0
-align 16
-  dw 0x9FB0
-  dw 0x0030
-  db 0
-  db 0
-  db 0
-align 16
-  dw 0x5000
-  dw 0x0040
-  db 4
-  db 0
-  db 0
-align 16
-  dw 0x1000
-  dw 0x0000
-  db 4
-  db 0
-  db "BIOS ROM", 0
-align 16
-  dw 0x0000
-align 16
-  dw 0x0000
-align 16
-  dw 0x0000
-align 16
-  dw 0x0000