os-k/kaleid/kernel/mm/gdt.asm

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;=----------------------------------------------------------------------------=;
; GNU GPL OS/K ;
; ;
; Desc: Interrupt Descriptor Table related functions ;
; ;
; ;
; Copyright © 2018-2020 The OS/K Team ;
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; ;
; 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]
global MmLoadGdt
global MmStoreGdt
;;
;; Loads the GDT
;;
MmLoadGdt:
;; Loading the gdt via the gdtPtr pointer
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lgdt [rdi]
mov ax, si
ltr ax
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;; We must far jump because we changed the GDT
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lea rax, [.next]
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push rax
ret
.next:
;ltr dx ; the TSS
ret
;;
;; Stores the GDT
;;
MmStoreGdt:
;; Loading the gdt via the gdtPtr pointer
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sgdt [rdi]
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ret