NTR_Launcher/ndsbootloader/arm9code/mpu_reset.s
ApacheThunder a4e5a00409 Big changes....
* Stage2 launcher UI added. This is a heavily modified HBMenu with
ability to launch carts! This menu can be used to boot a bootloader NDS
file for flascharts that the direct cart launcher fails to boot.
* New audio files added for new menu.
* HBMenu UI loaded by default if booted with no cart inserted.
* INI file folder now located in NTR_Launcher folder instead. A default
ini file from NitroFS (if mount of nitrofs succeeds) will be copied to
SD if one is not present.
* Stage2 launchers are expected to be in NTR Launcehr folder though you
can navigate to any folder you want in the UI so stage2 launchers aren't
the only thing this can be used for. You can also use this as a means of
booting homebrew off SD in NTR mode.
2024-04-10 22:59:52 -05:00

111 lines
3.4 KiB
ArmAsm

/*
Copyright 2006 - 2015 Dave Murphy (WinterMute)
This program 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 2 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <nds/arm9/cache_asm.h>
.text
.align 4
.arm
.arch armv5te
.cpu arm946e-s
@---------------------------------------------------------------------------------
.global _start
.type _start STT_FUNC
@---------------------------------------------------------------------------------
_start:
@---------------------------------------------------------------------------------
@ Switch off MPU
mrc p15, 0, r0, c1, c0, 0
bic r0, r0, #PROTECT_ENABLE
mcr p15, 0, r0, c1, c0, 0
adr r12, mpu_initial_data
ldmia r12, {r0-r10}
mcr p15, 0, r0, c2, c0, 0
mcr p15, 0, r0, c2, c0, 1
mcr p15, 0, r1, c3, c0, 0
mcr p15, 0, r2, c5, c0, 2
mcr p15, 0, r3, c5, c0, 3
mcr p15, 0, r4, c6, c0, 0
mcr p15, 0, r5, c6, c1, 0
mcr p15, 0, r6, c6, c3, 0
mcr p15, 0, r7, c6, c4, 0
mcr p15, 0, r8, c6, c6, 0
mcr p15, 0, r9, c6, c7, 0
mcr p15, 0, r10, c9, c1, 0
mov r0, #0
mcr p15, 0, r0, c6, c2, 0 @ PU Protection Unit Data/Unified Region 2
mcr p15, 0, r0, c6, c5, 0 @ PU Protection Unit Data/Unified Region 5
mrc p15, 0, r0, c9, c1, 0 @ DTCM
mov r0, r0, lsr #12 @ base
mov r0, r0, lsl #12 @ size
add r0, r0, #0x4000 @ dtcm top
sub r0, r0, #4 @ irq vector
mov r1, #0
str r1, [r0]
sub r0, r0, #4 @ IRQ1 Check Bits
str r1, [r0]
sub r0, r0, #128
bic r0, r0, #7
msr cpsr_c, #0xd3 @ svc mode
mov sp, r0
sub r0, r0, #128
msr cpsr_c, #0xd2 @ irq mode
mov sp, r0
sub r0, r0, #128
msr cpsr_c, #0xdf @ system mode
mov sp, r0
@ enable cache & tcm
mrc p15, 0, r0, c1, c0, 0
ldr r1,= ITCM_ENABLE | DTCM_ENABLE | ICACHE_ENABLE | DCACHE_ENABLE
orr r0,r0,r1
mcr p15, 0, r0, c1, c0, 0
ldr r10, =0x2FFFE04
ldr r0, =0xE59FF018
str r0, [r10]
add r1, r10, #0x20
str r10, [r1]
bx r10
.pool
mpu_initial_data:
.word 0x00000042 @ p15,0,c2,c0,0..1,r0 ;PU Cachability Bits for Data/Unified+Instruction Protection Region
.word 0x00000002 @ p15,0,c3,c0,0,r1 ;PU Write-Bufferability Bits for Data Protection Regions
.word 0x15111011 @ p15,0,c5,c0,2,r2 ;PU Extended Access Permission Data/Unified Protection Region
.word 0x05100011 @ p15,0,c5,c0,3,r3 ;PU Extended Access Permission Instruction Protection Region
.word 0x04000033 @ p15,0,c6,c0,0,r4 ;PU Protection Unit Data/Unified Region 0
.word 0x0200002b @ p15,0,c6,c1,0,r5 ;PU Protection Unit Data/Unified Region 1 4MB
.word 0x08000035 @ p15,0,c6,c3,0,r6 ;PU Protection Unit Data/Unified Region 3
.word 0x0300001b @ p15,0,c6,c4,0,r7 ;PU Protection Unit Data/Unified Region 4
.word 0xffff001d @ p15,0,c6,c6,0,r8 ;PU Protection Unit Data/Unified Region 6
.word 0x02fff017 @ p15,0,c6,c7,0,r9 ;PU Protection Unit Data/Unified Region 7 4KB
.word 0x0300000a @ p15,0,c9,c1,0,r10 ;TCM Data TCM Base and Virtual Size