all repos — mgba @ 0a52f44fa822539200f5ae6aad1fe5f5a6a3ab0e

mGBA Game Boy Advance Emulator

src/gba/serialize.c (view raw)

  1/* Copyright (c) 2013-2016 Jeffrey Pfau
  2 *
  3 * This Source Code Form is subject to the terms of the Mozilla Public
  4 * License, v. 2.0. If a copy of the MPL was not distributed with this
  5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  6#include <mgba/internal/gba/serialize.h>
  7
  8#include <mgba/internal/arm/macros.h>
  9#include <mgba/internal/gba/bios.h>
 10#include <mgba/internal/gba/io.h>
 11
 12#include <mgba-util/memory.h>
 13#include <mgba-util/vfs.h>
 14
 15#include <fcntl.h>
 16
 17const uint32_t GBA_SAVESTATE_MAGIC = 0x01000000;
 18const uint32_t GBA_SAVESTATE_VERSION = 0x00000003;
 19
 20mLOG_DEFINE_CATEGORY(GBA_STATE, "GBA Savestate", "gba.serialize");
 21
 22struct GBABundledState {
 23	struct GBASerializedState* state;
 24	struct mStateExtdata* extdata;
 25};
 26
 27void GBASerialize(struct GBA* gba, struct GBASerializedState* state) {
 28	STORE_32(GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION, 0, &state->versionMagic);
 29	STORE_32(gba->biosChecksum, 0, &state->biosChecksum);
 30	STORE_32(gba->romCrc32, 0, &state->romCrc32);
 31	STORE_32(gba->timing.masterCycles, 0, &state->masterCycles);
 32	STORE_64LE(gba->timing.globalCycles, 0, &state->globalCycles);
 33
 34	if (gba->memory.rom) {
 35		state->id = ((struct GBACartridge*) gba->memory.rom)->id;
 36		memcpy(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title));
 37	} else {
 38		state->id = 0;
 39		memset(state->title, 0, sizeof(state->title));
 40	}
 41
 42	int i;
 43	for (i = 0; i < 16; ++i) {
 44		STORE_32(gba->cpu->gprs[i], i * sizeof(state->cpu.gprs[0]), state->cpu.gprs);
 45	}
 46	STORE_32(gba->cpu->cpsr.packed, 0, &state->cpu.cpsr.packed);
 47	STORE_32(gba->cpu->spsr.packed, 0, &state->cpu.spsr.packed);
 48	STORE_32(gba->cpu->cycles, 0, &state->cpu.cycles);
 49	STORE_32(gba->cpu->nextEvent, 0, &state->cpu.nextEvent);
 50	for (i = 0; i < 6; ++i) {
 51		int j;
 52		for (j = 0; j < 7; ++j) {
 53			STORE_32(gba->cpu->bankedRegisters[i][j], (i * 7 + j) * sizeof(gba->cpu->bankedRegisters[0][0]), state->cpu.bankedRegisters);
 54		}
 55		STORE_32(gba->cpu->bankedSPSRs[i], i * sizeof(gba->cpu->bankedSPSRs[0]), state->cpu.bankedSPSRs);
 56	}
 57
 58	STORE_32(gba->memory.biosPrefetch, 0, &state->biosPrefetch);
 59	STORE_32(gba->cpu->prefetch[0], 0, state->cpuPrefetch);
 60	STORE_32(gba->cpu->prefetch[1], 4, state->cpuPrefetch);
 61	STORE_32(gba->memory.lastPrefetchedPc, 0, &state->lastPrefetchedPc);
 62
 63	GBASerializedMiscFlags miscFlags = 0;
 64	miscFlags = GBASerializedMiscFlagsSetHalted(miscFlags, gba->cpu->halted);
 65	miscFlags = GBASerializedMiscFlagsSetPOSTFLG(miscFlags, gba->memory.io[REG_POSTFLG >> 1] & 1);
 66	if (mTimingIsScheduled(&gba->timing, &gba->irqEvent)) {
 67		miscFlags = GBASerializedMiscFlagsFillIrqPending(miscFlags);
 68		STORE_32(gba->irqEvent.when - mTimingCurrentTime(&gba->timing), 0, &state->nextIrq);
 69	}
 70	miscFlags = GBASerializedMiscFlagsSetBlocked(miscFlags, gba->cpuBlocked);
 71	STORE_32(miscFlags, 0, &state->miscFlags);
 72	STORE_32(gba->biosStall, 0, &state->biosStall);
 73
 74	GBAMemorySerialize(&gba->memory, state);
 75	GBAIOSerialize(gba, state);
 76	GBAVideoSerialize(&gba->video, state);
 77	GBAAudioSerialize(&gba->audio, state);
 78	GBASavedataSerialize(&gba->memory.savedata, state);
 79}
 80
 81bool GBADeserialize(struct GBA* gba, const struct GBASerializedState* state) {
 82	bool error = false;
 83	int32_t check;
 84	uint32_t ucheck;
 85	LOAD_32(ucheck, 0, &state->versionMagic);
 86	if (ucheck > GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION) {
 87		mLOG(GBA_STATE, WARN, "Invalid or too new savestate: expected %08X, got %08X", GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION, ucheck);
 88		error = true;
 89	} else if (ucheck < GBA_SAVESTATE_MAGIC) {
 90		mLOG(GBA_STATE, WARN, "Invalid savestate: expected %08X, got %08X", GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION, ucheck);
 91		error = true;
 92	} else if (ucheck < GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION) {
 93		mLOG(GBA_STATE, WARN, "Old savestate: expected %08X, got %08X, continuing anyway", GBA_SAVESTATE_MAGIC + GBA_SAVESTATE_VERSION, ucheck);
 94	}
 95	LOAD_32(ucheck, 0, &state->biosChecksum);
 96	if (ucheck != gba->biosChecksum) {
 97		mLOG(GBA_STATE, WARN, "Savestate created using a different version of the BIOS: expected %08X, got %08X", gba->biosChecksum, ucheck);
 98		uint32_t pc;
 99		LOAD_32(pc, ARM_PC * sizeof(state->cpu.gprs[0]), state->cpu.gprs);
100		if ((ucheck == GBA_BIOS_CHECKSUM || gba->biosChecksum == GBA_BIOS_CHECKSUM) && pc < SIZE_BIOS && pc >= 0x20) {
101			error = true;
102		}
103	}
104	if (gba->memory.rom && (state->id != ((struct GBACartridge*) gba->memory.rom)->id || memcmp(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title)))) {
105		mLOG(GBA_STATE, WARN, "Savestate is for a different game");
106		error = true;
107	} else if (!gba->memory.rom && state->id != 0) {
108		mLOG(GBA_STATE, WARN, "Savestate is for a game, but no game loaded");
109		error = true;
110	}
111	LOAD_32(ucheck, 0, &state->romCrc32);
112	if (ucheck != gba->romCrc32) {
113		mLOG(GBA_STATE, WARN, "Savestate is for a different version of the game");
114	}
115	LOAD_32(check, 0, &state->cpu.cycles);
116	if (check < 0) {
117		mLOG(GBA_STATE, WARN, "Savestate is corrupted: CPU cycles are negative");
118		error = true;
119	}
120	if (check >= (int32_t) GBA_ARM7TDMI_FREQUENCY) {
121		mLOG(GBA_STATE, WARN, "Savestate is corrupted: CPU cycles are too high");
122		error = true;
123	}
124	LOAD_32(check, ARM_PC * sizeof(state->cpu.gprs[0]), state->cpu.gprs);
125	int region = (check >> BASE_OFFSET);
126	if ((region == REGION_CART0 || region == REGION_CART1 || region == REGION_CART2) && ((check - WORD_SIZE_ARM) & SIZE_CART0) >= gba->memory.romSize - WORD_SIZE_ARM) {
127		mLOG(GBA_STATE, WARN, "Savestate created using a differently sized version of the ROM");
128		error = true;
129	}
130	if (error) {
131		return false;
132	}
133	mTimingClear(&gba->timing);
134	LOAD_32(gba->timing.masterCycles, 0, &state->masterCycles);
135	LOAD_64LE(gba->timing.globalCycles, 0, &state->globalCycles);
136
137	size_t i;
138	for (i = 0; i < 16; ++i) {
139		LOAD_32(gba->cpu->gprs[i], i * sizeof(gba->cpu->gprs[0]), state->cpu.gprs);
140	}
141	LOAD_32(gba->cpu->cpsr.packed, 0, &state->cpu.cpsr.packed);
142	LOAD_32(gba->cpu->spsr.packed, 0, &state->cpu.spsr.packed);
143	LOAD_32(gba->cpu->cycles, 0, &state->cpu.cycles);
144	LOAD_32(gba->cpu->nextEvent, 0, &state->cpu.nextEvent);
145	for (i = 0; i < 6; ++i) {
146		int j;
147		for (j = 0; j < 7; ++j) {
148			LOAD_32(gba->cpu->bankedRegisters[i][j], (i * 7 + j) * sizeof(gba->cpu->bankedRegisters[0][0]), state->cpu.bankedRegisters);
149		}
150		LOAD_32(gba->cpu->bankedSPSRs[i], i * sizeof(gba->cpu->bankedSPSRs[0]), state->cpu.bankedSPSRs);
151	}
152	gba->cpu->privilegeMode = gba->cpu->cpsr.priv;
153	gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
154	if (state->biosPrefetch) {
155		LOAD_32(gba->memory.biosPrefetch, 0, &state->biosPrefetch);
156	}
157	LOAD_32(gba->memory.lastPrefetchedPc, 0, &state->lastPrefetchedPc);
158	if (gba->cpu->cpsr.t) {
159		gba->cpu->executionMode = MODE_THUMB;
160		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
161			LOAD_32(gba->cpu->prefetch[0], 0, state->cpuPrefetch);
162			LOAD_32(gba->cpu->prefetch[1], 4, state->cpuPrefetch);
163			gba->cpu->prefetch[0] &= 0xFFFF;
164			gba->cpu->prefetch[1] &= 0xFFFF;
165		} else {
166			// Maintain backwards compat
167			LOAD_16(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
168			LOAD_16(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
169		}
170	} else {
171		gba->cpu->executionMode = MODE_ARM;
172		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
173			LOAD_32(gba->cpu->prefetch[0], 0, state->cpuPrefetch);
174			LOAD_32(gba->cpu->prefetch[1], 4, state->cpuPrefetch);
175		} else {
176			// Maintain backwards compat
177			LOAD_32(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
178			LOAD_32(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
179		}
180	}
181	GBASerializedMiscFlags miscFlags = 0;
182	LOAD_32(miscFlags, 0, &state->miscFlags);
183	gba->cpu->halted = GBASerializedMiscFlagsGetHalted(miscFlags);
184	gba->memory.io[REG_POSTFLG >> 1] = GBASerializedMiscFlagsGetPOSTFLG(miscFlags);
185	if (GBASerializedMiscFlagsIsIrqPending(miscFlags)) {
186		int32_t when;
187		LOAD_32(when, 0, &state->nextIrq);
188		mTimingSchedule(&gba->timing, &gba->irqEvent, when);		
189	}
190	gba->cpuBlocked = GBASerializedMiscFlagsGetBlocked(miscFlags);
191	LOAD_32(gba->biosStall, 0, &state->biosStall);
192
193	GBAVideoDeserialize(&gba->video, state);
194	GBAMemoryDeserialize(&gba->memory, state);
195	GBAIODeserialize(gba, state);
196	GBAAudioDeserialize(&gba->audio, state);
197	GBASavedataDeserialize(&gba->memory.savedata, state);
198
199	gba->timing.reroot = gba->timing.root;
200	gba->timing.root = NULL;
201
202	return true;
203}