66 lines
2.4 KiB
NASM
66 lines
2.4 KiB
NASM
|
;=----------------------------------------------------------------------------=;
|
||
|
|
; GNU GPL OS/K ;
|
||
|
|
; ;
|
||
|
|
; Desc: Interrupt Descriptor Table related functions ;
|
||
|
|
; ;
|
||
|
|
; ;
|
||
|
|
; Copyright © 2018-2019 The OS/K Team ;
|
||
|
|
; ;
|
||
|
|
; This file is part of OS/K. ;
|
||
|
|
; ;
|
||
|
|
; OS/K is free software: you can redistribute it and/or modify ;
|
||
|
|
; it under the terms of the GNU General Public License as published by ;
|
||
|
|
; the Free Software Foundation, either version 3 of the License, or ;
|
||
|
|
; (at your option) any later version. ;
|
||
|
|
; ;
|
||
|
|
; OS/K is distributed in the hope that it will be useful, ;
|
||
|
|
; but WITHOUT ANY WARRANTY; without even the implied warranty of ;
|
||
|
|
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;
|
||
|
|
; GNU General Public License for more details. ;
|
||
|
|
; ;
|
||
|
|
; You should have received a copy of the GNU General Public License ;
|
||
|
|
; along with OS/K. If not, see <https://www.gnu.org/licenses/>. ;
|
||
|
|
;=----------------------------------------------------------------------------=;
|
||
|
|
|
||
|
|
[BITS 64]
|
||
|
|
|
||
|
|
extern gdtPtr
|
||
|
|
|
||
|
|
global MmLoadGdt
|
||
|
|
global MmStoreGdt
|
||
|
|
|
||
|
|
;;
|
||
|
|
;; Loads the GDT
|
||
|
|
;;
|
||
|
|
MmLoadGdt:
|
||
|
|
|
||
|
|
;; Loading the gdt via the gdtPtr pointer
|
||
|
|
lgdt [rel gdtPtr]
|
||
|
|
|
||
|
|
;; Reloading the segment registers
|
||
|
|
mov ax, si ; data segment
|
||
|
|
mov ds, ax
|
||
|
|
mov es, ax
|
||
|
|
mov fs, ax
|
||
|
|
mov gs, ax
|
||
|
|
mov ss, ax
|
||
|
|
mov cs, di ; code segment
|
||
|
|
|
||
|
|
;; We must far jump because we changed the GDT
|
||
|
|
lea rax, [rel .next]
|
||
|
|
push rax
|
||
|
|
ret
|
||
|
|
|
||
|
|
.next:
|
||
|
|
;ltr dx ; the TSS
|
||
|
|
ret
|
||
|
|
|
||
|
|
;;
|
||
|
|
;; Stores the GDT
|
||
|
|
;;
|
||
|
|
MmStoreGdt:
|
||
|
|
|
||
|
|
;; Loading the gdt via the gdtPtr pointer
|
||
|
|
sgdt [rel gdtPtr]
|
||
|
|
ret
|