mirror of
https://gitlab.com/sortix/sortix.git
synced 2023-02-13 20:55:38 -05:00
72 lines
1.7 KiB
ArmAsm
72 lines
1.7 KiB
ArmAsm
|
/******************************************************************************
|
||
|
|
|
||
|
|
COPYRIGHT(C) JONAS 'SORTIE' TERMANSEN 2011.
|
||
|
|
|
||
|
|
This file is part of Sortix.
|
||
|
|
|
||
|
|
Sortix 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.
|
||
|
|
|
||
|
|
Sortix 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 Sortix. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
|
||
|
|
x64/gdt.cpp
|
||
|
|
Handles initialization of the 64-bit global descriptor table.
|
||
|
|
|
||
|
|
******************************************************************************/
|
||
|
|
|
||
|
|
.section .text
|
||
|
|
|
||
|
|
.global gdt_flush
|
||
|
|
.type gdt_flush, @function
|
||
|
|
gdt_flush:
|
||
|
|
# Load the new GDT pointer
|
||
|
|
lgdtq (%rdi)
|
||
|
|
|
||
|
|
# 0x10 is the offset in the GDT to our data segment
|
||
|
|
mov $0x10, %ax
|
||
|
|
mov %ax, %ds
|
||
|
|
mov %ax, %es
|
||
|
|
mov %ax, %fs
|
||
|
|
mov %ax, %gs
|
||
|
|
|
||
|
|
# 0x08 is the offset to our code segment: Far jump!
|
||
|
|
ljmp *GDT_FLUSH_POSTJMP
|
||
|
|
gdt_flush_postjmp:
|
||
|
|
ret
|
||
|
|
|
||
|
|
.global idt_flush
|
||
|
|
.type idt_flush, @function
|
||
|
|
idt_flush:
|
||
|
|
# Load the IDT pointer.
|
||
|
|
lidt (%rdi)
|
||
|
|
|
||
|
|
# Enable interrupts
|
||
|
|
sti
|
||
|
|
ret
|
||
|
|
|
||
|
|
.global tss_flush
|
||
|
|
.type tss_flush, @function
|
||
|
|
tss_flush:
|
||
|
|
# Load the index of our TSS structure - The index is 0x28, as it is the 5th
|
||
|
|
# selector and each is 8 bytes long, but we set the bottom two bits (making
|
||
|
|
# 0x2B) so that it has an RPL of 3, not zero.
|
||
|
|
mov $0x2B, %ax
|
||
|
|
|
||
|
|
# Load the task state register.
|
||
|
|
ltr %ax
|
||
|
|
ret
|
||
|
|
|
||
|
|
.section .data
|
||
|
|
GDT_FLUSH_POSTJMP:
|
||
|
|
.long gdt_flush_postjmp
|
||
|
|
.word 0x08
|
||
|
|
|