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GB: Clean up BIOS detection

This commit is contained in:
Jeffrey Pfau 2016-09-17 10:37:05 -07:00
parent f8f75c4c91
commit f658bc00d9
3 changed files with 45 additions and 28 deletions
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16
src/gb/core.c
View File

@ -214,9 +214,19 @@ static void _GBCoreReset(struct mCore* core) {
}
#if !defined(MINIMAL_CORE) || MINIMAL_CORE < 2
struct VFile* bios = 0;
struct VFile* bios = NULL;
if (core->opts.useBios) {
if (!core->opts.bios) {
bool found = false;
if (core->opts.bios) {
bios = VFileOpen(core->opts.bios, O_RDONLY);
if (bios && GBIsBIOS(bios)) {
found = true;
} else if (bios) {
bios->close(bios);
bios = NULL;
}
}
if (!found) {
char path[PATH_MAX];
GBDetectModel(gb);
mCoreConfigDirectory(path, PATH_MAX);
@ -233,8 +243,6 @@ static void _GBCoreReset(struct mCore* core) {
break;
};
bios = VFileOpen(path, O_RDONLY);
} else {
bios = VFileOpen(core->opts.bios, O_RDONLY);
}
}
if (bios) {

54
src/gb/gb.c
View File

@ -23,6 +23,9 @@ const uint32_t SGB_LR35902_FREQUENCY = 0x418B1E;
const uint32_t GB_COMPONENT_MAGIC = 0x400000;
const uint32_t DMG_2_BIOS_CHECKSUM = 0x59C8598E;
const uint32_t CGB_BIOS_CHECKSUM = 0x41884E46;
mLOG_DEFINE_CATEGORY(GB, "GB");
static void GBInit(void* cpu, struct mCPUComponent* component);
@ -290,28 +293,38 @@ void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh) {
irqh->halt = GBHalt;
}
static uint32_t _GBBiosCRC32(struct VFile* vf) {
ssize_t size = vf->size(vf);
if (size <= 0 || size > GB_SIZE_CART_BANK0) {
return 0;
}
void* bios = vf->map(vf, size, MAP_READ);
uint32_t biosCrc = doCrc32(bios, size);
vf->unmap(vf, bios, size);
return biosCrc;
}
bool GBIsBIOS(struct VFile* vf) {
switch (_GBBiosCRC32(vf)) {
case DMG_2_BIOS_CHECKSUM:
case CGB_BIOS_CHECKSUM:
return true;
default:
return false;
}
}
void GBReset(struct LR35902Core* cpu) {
struct GB* gb = (struct GB*) cpu->master;
GBDetectModel(gb);
if (gb->biosVf) {
if (!GBIsBIOS(gb->biosVf)) {
gb->biosVf->close(gb->biosVf);
gb->biosVf = NULL;
} else {
gb->biosVf->seek(gb->biosVf, 0, SEEK_SET);
gb->memory.romBase = malloc(GB_SIZE_CART_BANK0);
ssize_t size = gb->biosVf->read(gb->biosVf, gb->memory.romBase, GB_SIZE_CART_BANK0);
uint32_t biosCrc = doCrc32(gb->memory.romBase, size);
switch (biosCrc) {
case 0x59C8598E:
break;
case 0x41884E46:
break;
default:
gb->biosVf->close(gb->biosVf);
gb->biosVf = NULL;
free(gb->memory.romBase);
gb->memory.romBase = gb->memory.rom;
break;
}
if (gb->biosVf) {
memcpy(&gb->memory.romBase[size], &gb->memory.rom[size], GB_SIZE_CART_BANK0 - size);
if (size > 0x100) {
memcpy(&gb->memory.romBase[0x100], &gb->memory.rom[0x100], sizeof(struct GBCartridge));
@ -386,22 +399,17 @@ void GBDetectModel(struct GB* gb) {
return;
}
if (gb->biosVf) {
gb->biosVf->seek(gb->biosVf, 0, SEEK_SET);
void* bios = malloc(GB_SIZE_CART_BANK0);
ssize_t size = gb->biosVf->read(gb->biosVf, bios, GB_SIZE_CART_BANK0);
uint32_t biosCrc = doCrc32(gb->memory.romBase, size);
switch (biosCrc) {
case 0x59C8598E:
switch (_GBBiosCRC32(gb->biosVf)) {
case DMG_2_BIOS_CHECKSUM:
gb->model = GB_MODEL_DMG;
break;
case 0x41884E46:
case CGB_BIOS_CHECKSUM:
gb->model = GB_MODEL_CGB;
break;
default:
gb->biosVf->close(gb->biosVf);
gb->biosVf = NULL;
}
free(bios);
}
if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];

1
src/gb/gb.h
View File

@ -116,6 +116,7 @@ bool GBLoadSave(struct GB* gb, struct VFile* vf);
void GBYankROM(struct GB* gb);
void GBUnloadROM(struct GB* gb);
bool GBIsBIOS(struct VFile* vf);
void GBLoadBIOS(struct GB* gb, struct VFile* vf);
void GBSramClean(struct GB* gb, uint32_t frameCount);