GBA: Refine multiboot detection (fixes #2192)

This commit is contained in:
Vicki Pfau 2022-02-20 21:05:12 -08:00
parent 5b26099eac
commit 91911fe092
2 changed files with 21 additions and 1 deletions

View File

@ -47,6 +47,7 @@ Misc:
- Debugger: Save and restore CLI history
- GB Video: Add default SGB border
- GBA: Automatically skip BIOS if ROM has invalid logo
- GBA: Refine multiboot detection (fixes mgba.io/i/2192)
- GBA DMA: Enhanced logging (closes mgba.io/i/2454)
- GBA Video: Implement layer placement for OpenGL renderer (fixes mgba.io/i/1962)
- mGUI: Add margin to right-aligned menu text (fixes mgba.io/i/871)

View File

@ -672,6 +672,10 @@ bool GBAIsMB(struct VFile* vf) {
}
uint32_t pc = GBA_MB_MAGIC_OFFSET;
int wramAddrs = 0;
int wramLoads = 0;
int romAddrs = 0;
int romLoads = 0;
int i;
for (i = 0; i < 80; ++i) {
if (vf->read(vf, &signature, sizeof(signature)) != sizeof(signature)) {
@ -679,6 +683,12 @@ bool GBAIsMB(struct VFile* vf) {
}
pc += 4;
LOAD_32(opcode, 0, &signature);
if ((opcode & ~0x7FF) == BASE_WORKING_RAM) {
++wramAddrs;
}
if ((opcode & ~0x7FF) == BASE_CART0) {
++romAddrs;
}
ARMDecodeARM(opcode, &info);
if (info.mnemonic != ARM_MN_LDR) {
continue;
@ -700,10 +710,19 @@ bool GBAIsMB(struct VFile* vf) {
break;
}
if ((immediate & ~0x7FF) == BASE_WORKING_RAM) {
++wramLoads;
}
if ((immediate & ~0x7FF) == BASE_CART0) {
++romLoads;
}
}
}
if (romLoads + romAddrs > 2) {
return false;
}
if (wramLoads + wramAddrs) {
return true;
}
}
}
// Found a libgba-linked cart...these are a bit harder to detect.
return false;
}