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Implement RLUnCompWram/RLUnCompVram

This commit is contained in:
Jeffrey Pfau 2013-05-11 18:22:23 -07:00
parent a6d87bbfb9
commit f7ddc3a2b6
1 changed files with 55 additions and 0 deletions
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55
src/gba/gba-bios.c
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@ -8,6 +8,7 @@
#include <stdlib.h>
static void _unLz77(struct GBAMemory* memory, uint32_t source, uint8_t* dest);
static void _unRl(struct GBAMemory* memory, uint32_t source, uint8_t* dest);
static void _RegisterRamReset(struct GBA* gba) {
uint32_t registers = gba->cpu.gprs[0];
@ -233,6 +234,23 @@ void GBASwi16(struct ARMBoard* board, int immediate) {
break;
}
break;
case 0x14:
case 0x15:
switch (gba->cpu.gprs[1] >> BASE_OFFSET) {
case REGION_WORKING_RAM:
_unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.wram)[(gba->cpu.gprs[1] & (SIZE_WORKING_RAM - 1))]);
break;
case REGION_WORKING_IRAM:
_unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.iwram)[(gba->cpu.gprs[1] & (SIZE_WORKING_IRAM - 1))]);
break;
case REGION_VRAM:
_unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->video.renderer->vram)[(gba->cpu.gprs[1] & 0x0001FFFF)]);
break;
default:
GBALog(GBA_LOG_WARN, "Bad RL destination");
break;
}
break;
case 0x1F:
_MidiKey2Freq(gba);
break;
@ -283,3 +301,40 @@ static void _unLz77(struct GBAMemory* memory, uint32_t source, uint8_t* dest) {
}
}
}
static void _unRl(struct GBAMemory* memory, uint32_t source, uint8_t* dest) {
source = source & 0xFFFFFFFC;
int remaining = (GBALoad32(&memory->d, source, 0) & 0xFFFFFF00) >> 8;
int padding = (4 - remaining) & 0x3;
// We assume the signature byte (0x30) is correct
int blockheader;
int block;
uint32_t sPointer = source + 4;
uint8_t* dPointer = dest;
while (remaining > 0) {
blockheader = GBALoadU8(&memory->d, sPointer++, 0);
if (blockheader & 0x80) {
// Compressed
blockheader &= 0x7F;
blockheader += 3;
block = GBALoadU8(&memory->d, sPointer++, 0);
while (blockheader-- && remaining) {
--remaining;
*dPointer = block;
++dPointer;
}
} else {
// Uncompressed
blockheader++;
while (blockheader-- && remaining) {
--remaining;
*dPointer = GBALoadU8(&memory->d, sPointer++, 0);
++dPointer;
}
}
}
while (padding--) {
*dPointer = 0;
++dPointer;
}
}