diff options
author | mrb0nk500 <b0nk@b0nk.xyz> | 2023-01-28 09:31:59 -0400 |
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committer | mrb0nk500 <b0nk@b0nk.xyz> | 2023-01-28 19:04:05 -0400 |
commit | a88ef2fde041e5d733b5cbe2728b15ca149d1671 (patch) | |
tree | b4b01c75a640810f6549c485a382242d25a19a97 /src/Dolphin/os/__start.c |
Initial commit
Diffstat (limited to 'src/Dolphin/os/__start.c')
-rw-r--r-- | src/Dolphin/os/__start.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/Dolphin/os/__start.c b/src/Dolphin/os/__start.c new file mode 100644 index 0000000..1113e15 --- /dev/null +++ b/src/Dolphin/os/__start.c @@ -0,0 +1,163 @@ +// This file was taken from the Metroid Prime decompilation project. +// https://github.com/PrimeDecomp/prime/blob/main/src/Dolphin/os/__start.c +#include "dolphin/__start.h" +#include "__ppc_eabi_linker.h" + +void __check_pad3(void) { + if ((Pad3Button & 0x0eef) == 0x0eef) { + OSResetSystem(OS_RESET_RESTART, 0, FALSE); + } + return; +} + +__declspec(weak) asm void __start(void) { + // clang-format off + nofralloc + bl __init_registers + bl __init_hardware + li r0, -1 + stwu r1, -8(r1) + stw r0, 4(r1) + stw r0, 0(r1) + bl __init_data + li r0, 0 + lis r6, EXCEPTIONMASK_ADDR@ha + addi r6, r6, EXCEPTIONMASK_ADDR@l + stw r0, 0(r6) + lis r6, BOOTINFO2_ADDR@ha + addi r6, r6, BOOTINFO2_ADDR@l + lwz r6, 0(r6) + +_check_TRK: + cmplwi r6, 0 + beq _load_lomem_debug_flag + lwz r7, OS_BI2_DEBUGFLAG_OFFSET(r6) + b _check_debug_flag + +_load_lomem_debug_flag: + lis r5, ARENAHI_ADDR@ha + addi r5, r5, ARENAHI_ADDR@l + lwz r5, 0(r5) + cmplwi r5, 0 + beq _goto_main + lis r7, DEBUGFLAG_ADDR@ha + addi r7, r7, DEBUGFLAG_ADDR@l + lwz r7, 0(r7) + +_check_debug_flag: + li r5, 0 + cmplwi r7, 2 + beq _goto_inittrk + cmplwi r7, 3 + bne _goto_main + li r5, 1 + +_goto_inittrk: + lis r6, InitMetroTRK@ha + addi r6, r6, InitMetroTRK@l + mtlr r6 + blrl + +_goto_main: + lis r6, BOOTINFO2_ADDR@ha + addi r6, r6, BOOTINFO2_ADDR@l + lwz r5, 0(r6) + cmplwi r5, 0 + beq+ _no_args + lwz r6, 8(r5) + cmplwi r6, 0 + beq+ _no_args + add r6, r5, r6 + lwz r14, 0(r6) + cmplwi r14, 0 + beq _no_args + addi r15, r6, 4 + mtctr r14 + +_loop: + addi r6, r6, 4 + lwz r7, 0(r6) + add r7, r7, r5 + stw r7, 0(r6) + bdnz _loop + lis r5, ARENAHI_ADDR@ha + addi r5, r5, ARENAHI_ADDR@l + rlwinm r7, r15, 0, 0, 0x1a + stw r7, 0(r5) + b _end_of_parseargs + +_no_args: + li r14, 0 + li r15, 0 + +_end_of_parseargs: + bl DBInit + bl OSInit + lis r4, DVD_DEVICECODE_ADDR@ha + addi r4, r4, DVD_DEVICECODE_ADDR@l + lhz r3, 0(r4) + andi. r5, r3, 0x8000 + beq _check_pad3 + andi. r3, r3, 0x7fff + cmplwi r3, 1 + bne _goto_skip_init_bba + +_check_pad3: + bl __check_pad3 + +_goto_skip_init_bba: + bl __init_user + mr r3, r14 + mr r4, r15 + bl main + b exit + // clang-format on +} + +asm static void __init_registers(void) { + // clang-format off + nofralloc + lis r1, _stack_addr@h + ori r1, r1, _stack_addr@l + lis r2, _SDA2_BASE_@h + ori r2, r2, _SDA2_BASE_@l + lis r13, _SDA_BASE_@h + ori r13, r13, _SDA_BASE_@l + blr + // clang-format on +} + +inline static void __copy_rom_section(void* dst, const void* src, unsigned long size) { + if (size && (dst != src)) { + memcpy(dst, src, size); + __flush_cache(dst, size); + } +} + +inline static void __init_bss_section(void* dst, unsigned long size) { + if (size) { + memset(dst, 0, size); + } +} + +#pragma scheduling off +void __init_data(void) { + __rom_copy_info* dci; + __bss_init_info* bii; + + dci = _rom_copy_info; + while (TRUE) { + if (dci->size == 0) + break; + __copy_rom_section(dci->addr, dci->rom, dci->size); + dci++; + } + + bii = _bss_init_info; + while (TRUE) { + if (bii->size == 0) + break; + __init_bss_section(bii->addr, bii->size); + bii++; + } +} |