mirror of
https://github.com/Atmosphere-NX/Atmosphere
synced 2024-11-10 15:16:34 +00:00
87 lines
2.1 KiB
ArmAsm
87 lines
2.1 KiB
ArmAsm
|
/*
|
||
|
|
* Copyright (c) 2018 Atmosphère-NX
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify it
|
||
|
|
* under the terms and conditions of the GNU General Public License,
|
||
|
|
* version 2, as published by the Free Software Foundation.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope 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 this program. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
.macro CLEAR_GPR_REG_ITER
|
||
|
|
mov r\@, #0
|
||
|
|
.endm
|
||
|
|
|
||
|
|
.section .text.start, "ax", %progbits
|
||
|
|
.arm
|
||
|
|
.align 5
|
||
|
|
.global _start
|
||
|
|
.type _start, %function
|
||
|
|
_start:
|
||
|
|
/* Switch to system mode, mask all interrupts, clear all flags */
|
||
|
|
msr cpsr_cxsf, #0xDF
|
||
|
|
|
||
|
|
/* Relocate ourselves if necessary */
|
||
|
|
ldr r2, =__start__
|
||
|
|
adr r3, _start
|
||
|
|
cmp r2, r3
|
||
|
|
beq _relocation_loop_end
|
||
|
|
|
||
|
|
ldr r4, =_relocation_loop_end
|
||
|
|
mov r4, #0x1000
|
||
|
|
mov r1, #0x0
|
||
|
|
_relocation_loop:
|
||
|
|
ldmia r3!, {r5-r12}
|
||
|
|
stmia r2!, {r5-r12}
|
||
|
|
add r1, r1, #0x20
|
||
|
|
cmp r1, r4
|
||
|
|
bne _relocation_loop
|
||
|
|
|
||
|
|
ldr r12, =_second_relocation_start
|
||
|
|
bx r12
|
||
|
|
|
||
|
|
_second_relocation_start:
|
||
|
|
ldr r4, =__bss_start__
|
||
|
|
sub r4, r4, r2
|
||
|
|
mov r1, #0x0
|
||
|
|
|
||
|
|
_second_relocation_loop:
|
||
|
|
ldmia r3!, {r5-r12}
|
||
|
|
stmia r2!, {r5-r12}
|
||
|
|
add r1, r1, #0x20
|
||
|
|
cmp r1, r4
|
||
|
|
bne _second_relocation_loop
|
||
|
|
|
||
|
|
ldr r12, =_relocation_loop_end
|
||
|
|
bx r12
|
||
|
|
|
||
|
|
_relocation_loop_end:
|
||
|
|
|
||
|
|
/* Set the stack pointer */
|
||
|
|
ldr sp, =__stack_top__
|
||
|
|
mov fp, #0
|
||
|
|
bl __program_init
|
||
|
|
|
||
|
|
/* Set r0 to r12 to 0 (for debugging) & call main */
|
||
|
|
.rept 13
|
||
|
|
CLEAR_GPR_REG_ITER
|
||
|
|
.endr
|
||
|
|
ldr lr, =__program_exit
|
||
|
|
b main
|
||
|
|
|
||
|
|
/* No need to include this in normal programs: */
|
||
|
|
.section .chainloader.text.start, "ax", %progbits
|
||
|
|
.arm
|
||
|
|
.align 5
|
||
|
|
.global relocate_and_chainload
|
||
|
|
.type relocate_and_chainload, %function
|
||
|
|
relocate_and_chainload:
|
||
|
|
ldr sp, =__stack_top__
|
||
|
|
b relocate_and_chainload_main
|