Update start.s (thanks @delebile and/or @d0k3)

This commit is contained in:
TuxSH 2016-05-28 23:47:30 +02:00
parent d239d82379
commit ae1033d975

View File

@ -10,20 +10,30 @@ start:
@ Change the stack pointer @ Change the stack pointer
mov sp, #0x27000000 mov sp, #0x27000000
@ Disable caches / mpu
mrc p15, 0, r4, c1, c0, 0 @ read control register
bic r4, #(1<<12) @ - instruction cache disable
bic r4, #(1<<2) @ - data cache disable
bic r4, #(1<<0) @ - mpu disable
mcr p15, 0, r4, c1, c0, 0 @ write control register
@ Give read/write access to all the memory regions @ Give read/write access to all the memory regions
ldr r0, =0x33333333 ldr r5, =0x33333333
mcr p15, 0, r0, c5, c0, 2 @ write data access mcr p15, 0, r5, c5, c0, 2 @ write data access
mcr p15, 0, r0, c5, c0, 3 @ write instruction access mcr p15, 0, r5, c5, c0, 3 @ write instruction access
@ Set MPU permissions and cache settings @ Sets MPU permissions and cache settings
ldr r0, =0xFFFF001D @ ffff0000 32k ldr r0, =0xFFFF001D @ ffff0000 32k | bootrom (unprotected part)
ldr r1, =0x01FF801D @ 01ff8000 32k ldr r1, =0x3000801B @ fff00000 16k | dtcm
ldr r2, =0x08000027 @ 08000000 1M ldr r2, =0x01FF801D @ 01ff8000 32k | itcm
ldr r3, =0x10000021 @ 10000000 128k ldr r3, =0x08000029 @ 08000000 2M | arm9 mem (O3DS / N3DS)
ldr r4, =0x10100025 @ 10100000 512k ldr r4, =0x10000029 @ 10000000 2M | io mem (ARM9 / first 2MB)
ldr r5, =0x20000035 @ 20000000 128M ldr r5, =0x20000037 @ 20000000 256M | fcram (O3DS / N3DS)
ldr r6, =0x1FF00027 @ 1FF00000 1M ldr r6, =0x1FF00027 @ 1FF00000 1M | dsp / axi wram
ldr r7, =0x1800002D @ 18000000 8M ldr r7, =0x1800002D @ 18000000 8M | vram (+ 2MB)
mov r10, #0x25
mov r11, #0x25
mov r12, #0x25
mcr p15, 0, r0, c6, c0, 0 mcr p15, 0, r0, c6, c0, 0
mcr p15, 0, r1, c6, c1, 0 mcr p15, 0, r1, c6, c1, 0
mcr p15, 0, r2, c6, c2, 0 mcr p15, 0, r2, c6, c2, 0
@ -32,25 +42,30 @@ start:
mcr p15, 0, r5, c6, c5, 0 mcr p15, 0, r5, c6, c5, 0
mcr p15, 0, r6, c6, c6, 0 mcr p15, 0, r6, c6, c6, 0
mcr p15, 0, r7, c6, c7, 0 mcr p15, 0, r7, c6, c7, 0
mov r0, #0x25 mcr p15, 0, r10, c3, c0, 0 @ Write bufferable 0, 2, 5
mcr p15, 0, r0, c3, c0, 0 @ Write bufferable 0, 2, 5 mcr p15, 0, r11, c2, c0, 0 @ Data cacheable 0, 2, 5
mcr p15, 0, r0, c2, c0, 0 @ Data cacheable 0, 2, 5 mcr p15, 0, r12, c2, c0, 1 @ Inst cacheable 0, 2, 5
mcr p15, 0, r0, c2, c0, 1 @ Inst cacheable 0, 2, 5
@ Enable dctm
ldr r1, =0x3000800A @ set dtcm
mcr p15, 0, r1, c9, c1, 0 @ set the dtcm Region Register
@ Enable caches @ Enable caches
mrc p15, 0, r0, c1, c0, 0 @ read control register mrc p15, 0, r4, c1, c0, 0 @ read control register
orr r0, r0, #(1<<12) @ - instruction cache enable orr r4, r4, #(1<<18) @ - itcm enable
orr r0, r0, #(1<<2) @ - data cache enable orr r4, r4, #(1<<16) @ - dtcm enable
orr r0, r0, #(1<<0) @ - mpu enable orr r4, r4, #(1<<12) @ - instruction cache enable
mcr p15, 0, r0, c1, c0, 0 @ write control register orr r4, r4, #(1<<2) @ - data cache enable
orr r4, r4, #(1<<0) @ - mpu enable
mcr p15, 0, r4, c1, c0, 0 @ write control register
@ Flush caches @ Flush caches
mov r0, #0 mov r5, #0
mcr p15, 0, r0, c7, c5, 0 @ flush I-cache mcr p15, 0, r5, c7, c5, 0 @ flush I-cache
mcr p15, 0, r0, c7, c6, 0 @ flush D-cache mcr p15, 0, r5, c7, c6, 0 @ flush D-cache
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer mcr p15, 0, r5, c7, c10, 4 @ drain write buffer
@ Fix mounting of SDMC @ Fixes mounting of SDMC
ldr r0, =0x10000020 ldr r0, =0x10000020
mov r1, #0x340 mov r1, #0x340
str r1, [r0] str r1, [r0]