all repos — mgba @ 3cf9446ba17e5fe7b0de4eff60fa063c55d7c6b2

mGBA Game Boy Advance Emulator

src/ds/ds.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 "ds.h"
  7
  8#include "arm/decoder.h"
  9#include "arm/debugger/debugger.h"
 10#include "arm/isa-inlines.h"
 11#include "ds/bios.h"
 12
 13#include "util/crc32.h"
 14#include "util/memory.h"
 15#include "util/math.h"
 16#include "util/vfs.h"
 17
 18mLOG_DEFINE_CATEGORY(DS, "DS");
 19
 20const uint32_t DS_ARM946ES_FREQUENCY = 0x1FF61FE;
 21const uint32_t DS_ARM7TDMI_FREQUENCY = 0xFFB0FF;
 22const uint32_t DS_COMPONENT_MAGIC = 0x1FF61FE;
 23
 24static const size_t DS_ROM_MAGIC_OFFSET = 0x15C;
 25static const uint8_t DS_ROM_MAGIC[] = { 0x56, 0xCF };
 26
 27enum {
 28	DS7_SP_BASE = 0x380FD80,
 29	DS7_SP_BASE_IRQ = 0x380FF80,
 30	DS7_SP_BASE_SVC = 0x380FFC0,
 31
 32	DS9_SP_BASE = 0x3002F7C,
 33	DS9_SP_BASE_IRQ = 0x3003F80,
 34	DS9_SP_BASE_SVC = 0x3003FC0,
 35};
 36
 37static void DSInit(void* cpu, struct mCPUComponent* component);
 38
 39static void DS7Reset(struct ARMCore* cpu);
 40static void DS7InterruptHandlerInit(struct ARMInterruptHandler* irqh);
 41
 42static void DS9Reset(struct ARMCore* cpu);
 43static void DS9InterruptHandlerInit(struct ARMInterruptHandler* irqh);
 44
 45static void DSProcessEvents(struct ARMCore* cpu);
 46static void DSHitStub(struct ARMCore* cpu, uint32_t opcode);
 47static void DSIllegal(struct ARMCore* cpu, uint32_t opcode);
 48static void DSBreakpoint(struct ARMCore* cpu, int immediate);
 49
 50void DSCreate(struct DS* ds) {
 51	ds->d.id = DS_COMPONENT_MAGIC;
 52	ds->d.init = DSInit;
 53	ds->d.deinit = NULL;
 54	ds->arm7 = NULL;
 55	ds->arm9 = NULL;
 56}
 57
 58static void DSInit(void* cpu, struct mCPUComponent* component) {
 59	struct DS* ds = (struct DS*) component;
 60	struct ARMCore* core = cpu;
 61	if (!ds->arm7) {
 62		// The ARM7 must get initialized first
 63		ds->arm7 = core;
 64		ds->debugger = 0;
 65		ds->sync = 0;
 66		return;
 67	}
 68	ds->arm9 = cpu;
 69
 70	ds->arm9->cp15.r1.c0 = ARMControlRegFillVE(0);
 71
 72	DS7InterruptHandlerInit(&ds->arm7->irqh);
 73	DS9InterruptHandlerInit(&ds->arm9->irqh);
 74	DSMemoryInit(ds);
 75
 76	ds->video.p = ds;
 77
 78	ds->springIRQ7 = 0;
 79	ds->springIRQ9 = 0;
 80	ds->keySource = NULL;
 81	ds->rtcSource = NULL;
 82	ds->rumble = NULL;
 83
 84	ds->romVf = NULL;
 85
 86	ds->keyCallback = NULL;
 87}
 88
 89void DSUnloadROM(struct DS* ds) {
 90	if (ds->romVf) {
 91		ds->romVf->close(ds->romVf);
 92		ds->romVf = NULL;
 93	}
 94}
 95
 96void DSDestroy(struct DS* ds) {
 97	DSUnloadROM(ds);
 98	DSMemoryDeinit(ds);
 99}
100
101void DS7InterruptHandlerInit(struct ARMInterruptHandler* irqh) {
102	irqh->reset = DS7Reset;
103	irqh->processEvents = DSProcessEvents;
104	irqh->swi16 = NULL;
105	irqh->swi32 = NULL;
106	irqh->hitIllegal = DSIllegal;
107	irqh->readCPSR = NULL;
108	irqh->hitStub = DSHitStub;
109	irqh->bkpt16 = DSBreakpoint;
110	irqh->bkpt32 = DSBreakpoint;
111}
112
113void DS9InterruptHandlerInit(struct ARMInterruptHandler* irqh) {
114	irqh->reset = DS9Reset;
115	irqh->processEvents = DSProcessEvents;
116	irqh->swi16 = NULL;
117	irqh->swi32 = NULL;
118	irqh->hitIllegal = DSIllegal;
119	irqh->readCPSR = NULL;
120	irqh->hitStub = DSHitStub;
121	irqh->bkpt16 = DSBreakpoint;
122	irqh->bkpt32 = DSBreakpoint;
123}
124
125void DS7Reset(struct ARMCore* cpu) {
126	ARMSetPrivilegeMode(cpu, MODE_IRQ);
127	cpu->gprs[ARM_SP] = DS7_SP_BASE_IRQ;
128	ARMSetPrivilegeMode(cpu, MODE_SUPERVISOR);
129	cpu->gprs[ARM_SP] = DS7_SP_BASE_SVC;
130	ARMSetPrivilegeMode(cpu, MODE_SYSTEM);
131	cpu->gprs[ARM_SP] = DS7_SP_BASE;
132}
133
134void DS9Reset(struct ARMCore* cpu) {
135	ARMSetPrivilegeMode(cpu, MODE_IRQ);
136	cpu->gprs[ARM_SP] = DS9_SP_BASE_IRQ;
137	ARMSetPrivilegeMode(cpu, MODE_SUPERVISOR);
138	cpu->gprs[ARM_SP] = DS9_SP_BASE_SVC;
139	ARMSetPrivilegeMode(cpu, MODE_SYSTEM);
140	cpu->gprs[ARM_SP] = DS9_SP_BASE;
141
142	struct DS* ds = (struct DS*) cpu->master;
143	DSMemoryReset(ds);
144}
145
146static void DSProcessEvents(struct ARMCore* cpu) {
147	struct DS* ds = (struct DS*) cpu->master;
148
149	if (ds->springIRQ7) {
150		ARMRaiseIRQ(cpu);
151		ds->springIRQ7 = 0;
152	}
153
154	do {
155		int32_t cycles = cpu->nextEvent;
156		int32_t nextEvent = INT_MAX;
157#ifndef NDEBUG
158		if (cycles < 0) {
159			mLOG(DS, FATAL, "Negative cycles passed: %i", cycles);
160		}
161#endif
162
163		cpu->cycles -= cycles;
164		cpu->nextEvent = nextEvent;
165
166		if (cpu->halted) {
167			cpu->cycles = cpu->nextEvent;
168		}
169	} while (cpu->cycles >= cpu->nextEvent);
170}
171
172void DSAttachDebugger(struct DS* ds, struct mDebugger* debugger) {
173	ds->debugger = (struct ARMDebugger*) debugger->platform;
174	ds->arm7->components[CPU_COMPONENT_DEBUGGER] = &debugger->d;
175	ds->arm9->components[CPU_COMPONENT_DEBUGGER] = &debugger->d;
176	ARMHotplugAttach(ds->arm7, CPU_COMPONENT_DEBUGGER);
177	ARMHotplugAttach(ds->arm9, CPU_COMPONENT_DEBUGGER);
178}
179
180
181void DSDetachDebugger(struct DS* ds) {
182	ds->debugger = NULL;
183	ARMHotplugDetach(ds->arm7, CPU_COMPONENT_DEBUGGER);
184	ARMHotplugDetach(ds->arm9, CPU_COMPONENT_DEBUGGER);
185	ds->arm7->components[CPU_COMPONENT_DEBUGGER] = NULL;
186	ds->arm9->components[CPU_COMPONENT_DEBUGGER] = NULL;
187}
188
189bool DSLoadROM(struct DS* ds, struct VFile* vf) {
190	DSUnloadROM(ds);
191	ds->romVf = vf;
192	// TODO: Checksum?
193	// TODO: error check
194	return true;
195}
196
197bool DSIsROM(struct VFile* vf) {
198	if (vf->seek(vf, DS_ROM_MAGIC_OFFSET, SEEK_SET) < 0) {
199		return false;
200	}
201	uint8_t signature[sizeof(DS_ROM_MAGIC)];
202	if (vf->read(vf, &signature, sizeof(signature)) != sizeof(signature)) {
203		return false;
204	}
205	return memcmp(signature, DS_ROM_MAGIC, sizeof(signature)) == 0;
206}
207
208bool DSLoadBIOS(struct DS* ds, struct VFile* vf) {
209	size_t size = vf->size(vf);
210	void* data = NULL;
211	uint32_t crc;
212	if (size == DS7_SIZE_BIOS) {
213		data = vf->map(vf, size, MAP_READ);
214	} else if (size == 0x1000) {
215		data = vf->map(vf, size, MAP_READ);
216	}
217	if (!data) {
218		return false;
219	}
220	crc = doCrc32(data, size);
221	if (crc == DS7_BIOS_CHECKSUM) {
222		ds->bios7Vf = vf;
223		ds->memory.bios7 = data;
224		mLOG(DS, INFO, "Official DS ARM7 BIOS detected");
225	} else if (crc == DS9_BIOS_CHECKSUM) {
226		ds->bios9Vf = vf;
227		ds->memory.bios9 = data;
228		mLOG(DS, INFO, "Official DS ARM9 BIOS detected");
229	} else {
230		mLOG(DS, WARN, "BIOS checksum incorrect");
231		vf->unmap(vf, data, size);
232		return false;
233	}
234	return true;
235}
236
237void DSGetGameCode(struct DS* ds, char* out) {
238	memset(out, 0, 8);
239	if (!ds->romVf) {
240		return;
241	}
242
243	struct DSCartridge* cart = ds->romVf->map(ds->romVf, sizeof(*cart), MAP_READ);
244	memcpy(out, "NTR-", 4);
245	memcpy(&out[4], &cart->id, 4);
246	ds->romVf->unmap(ds->romVf, cart, sizeof(*cart));
247}
248
249void DSGetGameTitle(struct DS* ds, char* out) {
250	memset(out, 0, 12);
251	if (!ds->romVf) {
252		return;
253	}
254
255	struct DSCartridge* cart = ds->romVf->map(ds->romVf, sizeof(*cart), MAP_READ);
256	memcpy(out, &cart->title, 4);
257	ds->romVf->unmap(ds->romVf, cart, sizeof(*cart));
258}
259
260void DSHitStub(struct ARMCore* cpu, uint32_t opcode) {
261	struct DS* ds = (struct DS*) cpu->master;
262	if (ds->debugger) {
263		struct mDebuggerEntryInfo info = {
264			.address = _ARMPCAddress(cpu),
265			.opcode = opcode
266		};
267		mDebuggerEnter(ds->debugger->d.p, DEBUGGER_ENTER_ILLEGAL_OP, &info);
268	}
269	// TODO: More sensible category?
270	mLOG(DS, ERROR, "Stub opcode: %08x", opcode);
271}
272
273void DSIllegal(struct ARMCore* cpu, uint32_t opcode) {
274	struct DS* ds = (struct DS*) cpu->master;
275	if (ds->debugger) {
276		struct mDebuggerEntryInfo info = {
277			.address = _ARMPCAddress(cpu),
278			.opcode = opcode
279		};
280		mDebuggerEnter(ds->debugger->d.p, DEBUGGER_ENTER_ILLEGAL_OP, &info);
281	} else {
282		ARMRaiseUndefined(cpu);
283	}
284}
285
286void DSBreakpoint(struct ARMCore* cpu, int immediate) {
287	struct DS* ds = (struct DS*) cpu->master;
288	if (immediate >= CPU_COMPONENT_MAX) {
289		return;
290	}
291	switch (immediate) {
292	case CPU_COMPONENT_DEBUGGER:
293		if (ds->debugger) {
294			struct mDebuggerEntryInfo info = {
295				.address = _ARMPCAddress(cpu)
296			};
297			mDebuggerEnter(ds->debugger->d.p, DEBUGGER_ENTER_BREAKPOINT, &info);
298		}
299		break;
300	default:
301		break;
302	}
303}