src/gba/bios.c (view raw)
1/* Copyright (c) 2013-2015 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/bios.h>
7
8#include <mgba/internal/arm/isa-inlines.h>
9#include <mgba/internal/arm/macros.h>
10#include <mgba/internal/gba/gba.h>
11#include <mgba/internal/gba/io.h>
12#include <mgba/internal/gba/memory.h>
13
14const uint32_t GBA_BIOS_CHECKSUM = 0xBAAE187F;
15const uint32_t GBA_DS_BIOS_CHECKSUM = 0xBAAE1880;
16
17mLOG_DEFINE_CATEGORY(GBA_BIOS, "GBA BIOS", "gba.bios");
18
19static void _unLz77(struct GBA* gba, int width);
20static void _unHuffman(struct GBA* gba);
21static void _unRl(struct GBA* gba, int width);
22static void _unFilter(struct GBA* gba, int inwidth, int outwidth);
23static void _unBitPack(struct GBA* gba);
24
25static void _SoftReset(struct GBA* gba) {
26 struct ARMCore* cpu = gba->cpu;
27 ARMSetPrivilegeMode(cpu, MODE_IRQ);
28 cpu->spsr.packed = 0;
29 cpu->gprs[ARM_LR] = 0;
30 cpu->gprs[ARM_SP] = SP_BASE_IRQ;
31 ARMSetPrivilegeMode(cpu, MODE_SUPERVISOR);
32 cpu->spsr.packed = 0;
33 cpu->gprs[ARM_LR] = 0;
34 cpu->gprs[ARM_SP] = SP_BASE_SUPERVISOR;
35 ARMSetPrivilegeMode(cpu, MODE_SYSTEM);
36 cpu->gprs[ARM_LR] = 0;
37 cpu->gprs[ARM_SP] = SP_BASE_SYSTEM;
38 int8_t flag = ((int8_t*) gba->memory.iwram)[0x7FFA];
39 memset(((int8_t*) gba->memory.iwram) + SIZE_WORKING_IRAM - 0x200, 0, 0x200);
40 if (flag) {
41 cpu->gprs[ARM_PC] = BASE_WORKING_RAM;
42 } else {
43 cpu->gprs[ARM_PC] = BASE_CART0;
44 }
45 _ARMSetMode(cpu, MODE_ARM);
46 int currentCycles = 0;
47 ARM_WRITE_PC;
48}
49
50static void _RegisterRamReset(struct GBA* gba) {
51 uint32_t registers = gba->cpu->gprs[0];
52 struct ARMCore* cpu = gba->cpu;
53 cpu->memory.store16(cpu, BASE_IO | REG_DISPCNT, 0x0080, 0);
54 if (registers & 0x01) {
55 memset(gba->memory.wram, 0, SIZE_WORKING_RAM);
56 }
57 if (registers & 0x02) {
58 memset(gba->memory.iwram, 0, SIZE_WORKING_IRAM - 0x200);
59 }
60 if (registers & 0x04) {
61 memset(gba->video.palette, 0, SIZE_PALETTE_RAM);
62 }
63 if (registers & 0x08) {
64 memset(gba->video.renderer->vram, 0, SIZE_VRAM);
65 }
66 if (registers & 0x10) {
67 memset(gba->video.oam.raw, 0, SIZE_OAM);
68 }
69 if (registers & 0x20) {
70 cpu->memory.store16(cpu, BASE_IO | REG_SIOCNT, 0x0000, 0);
71 cpu->memory.store16(cpu, BASE_IO | REG_RCNT, RCNT_INITIAL, 0);
72 cpu->memory.store16(cpu, BASE_IO | REG_SIOMLT_SEND, 0, 0);
73 cpu->memory.store16(cpu, BASE_IO | REG_JOYCNT, 0, 0);
74 cpu->memory.store32(cpu, BASE_IO | REG_JOY_RECV_LO, 0, 0);
75 cpu->memory.store32(cpu, BASE_IO | REG_JOY_TRANS_LO, 0, 0);
76 }
77 if (registers & 0x40) {
78 cpu->memory.store16(cpu, BASE_IO | REG_SOUND1CNT_LO, 0, 0);
79 cpu->memory.store16(cpu, BASE_IO | REG_SOUND1CNT_HI, 0, 0);
80 cpu->memory.store16(cpu, BASE_IO | REG_SOUND1CNT_X, 0, 0);
81 cpu->memory.store16(cpu, BASE_IO | REG_SOUND2CNT_LO, 0, 0);
82 cpu->memory.store16(cpu, BASE_IO | REG_SOUND2CNT_HI, 0, 0);
83 cpu->memory.store16(cpu, BASE_IO | REG_SOUND3CNT_LO, 0, 0);
84 cpu->memory.store16(cpu, BASE_IO | REG_SOUND3CNT_HI, 0, 0);
85 cpu->memory.store16(cpu, BASE_IO | REG_SOUND3CNT_X, 0, 0);
86 cpu->memory.store16(cpu, BASE_IO | REG_SOUND4CNT_LO, 0, 0);
87 cpu->memory.store16(cpu, BASE_IO | REG_SOUND4CNT_HI, 0, 0);
88 cpu->memory.store16(cpu, BASE_IO | REG_SOUNDCNT_LO, 0, 0);
89 cpu->memory.store16(cpu, BASE_IO | REG_SOUNDCNT_HI, 0, 0);
90 cpu->memory.store16(cpu, BASE_IO | REG_SOUNDCNT_X, 0, 0);
91 cpu->memory.store16(cpu, BASE_IO | REG_SOUNDBIAS, 0x200, 0);
92 memset(gba->audio.psg.ch3.wavedata32, 0, sizeof(gba->audio.psg.ch3.wavedata32));
93 }
94 if (registers & 0x80) {
95 cpu->memory.store16(cpu, BASE_IO | 0x04, 0, 0);
96 cpu->memory.store16(cpu, BASE_IO | 0x06, 0, 0);
97 cpu->memory.store16(cpu, BASE_IO | 0x08, 0, 0);
98 cpu->memory.store16(cpu, BASE_IO | 0x0A, 0, 0);
99 cpu->memory.store16(cpu, BASE_IO | 0x0C, 0, 0);
100 cpu->memory.store16(cpu, BASE_IO | 0x0E, 0, 0);
101 cpu->memory.store16(cpu, BASE_IO | 0x10, 0, 0);
102 cpu->memory.store16(cpu, BASE_IO | 0x12, 0, 0);
103 cpu->memory.store16(cpu, BASE_IO | 0x14, 0, 0);
104 cpu->memory.store16(cpu, BASE_IO | 0x16, 0, 0);
105 cpu->memory.store16(cpu, BASE_IO | 0x18, 0, 0);
106 cpu->memory.store16(cpu, BASE_IO | 0x1A, 0, 0);
107 cpu->memory.store16(cpu, BASE_IO | 0x1C, 0, 0);
108 cpu->memory.store16(cpu, BASE_IO | 0x1E, 0, 0);
109 cpu->memory.store16(cpu, BASE_IO | REG_BG2PA, 0x100, 0);
110 cpu->memory.store16(cpu, BASE_IO | REG_BG2PB, 0, 0);
111 cpu->memory.store16(cpu, BASE_IO | REG_BG2PC, 0, 0);
112 cpu->memory.store16(cpu, BASE_IO | REG_BG2PD, 0x100, 0);
113 cpu->memory.store32(cpu, BASE_IO | 0x28, 0, 0);
114 cpu->memory.store32(cpu, BASE_IO | 0x2C, 0, 0);
115 cpu->memory.store16(cpu, BASE_IO | REG_BG3PA, 0x100, 0);
116 cpu->memory.store16(cpu, BASE_IO | REG_BG3PB, 0, 0);
117 cpu->memory.store16(cpu, BASE_IO | REG_BG3PC, 0, 0);
118 cpu->memory.store16(cpu, BASE_IO | REG_BG3PD, 0x100, 0);
119 cpu->memory.store32(cpu, BASE_IO | 0x38, 0, 0);
120 cpu->memory.store32(cpu, BASE_IO | 0x3C, 0, 0);
121 cpu->memory.store16(cpu, BASE_IO | 0x40, 0, 0);
122 cpu->memory.store16(cpu, BASE_IO | 0x42, 0, 0);
123 cpu->memory.store16(cpu, BASE_IO | 0x44, 0, 0);
124 cpu->memory.store16(cpu, BASE_IO | 0x46, 0, 0);
125 cpu->memory.store16(cpu, BASE_IO | 0x48, 0, 0);
126 cpu->memory.store16(cpu, BASE_IO | 0x4A, 0, 0);
127 cpu->memory.store16(cpu, BASE_IO | 0x4C, 0, 0);
128 cpu->memory.store16(cpu, BASE_IO | 0x50, 0, 0);
129 cpu->memory.store16(cpu, BASE_IO | 0x52, 0, 0);
130 cpu->memory.store16(cpu, BASE_IO | 0x54, 0, 0);
131 cpu->memory.store16(cpu, BASE_IO | 0xB0, 0, 0);
132 cpu->memory.store16(cpu, BASE_IO | 0xB2, 0, 0);
133 cpu->memory.store16(cpu, BASE_IO | 0xB4, 0, 0);
134 cpu->memory.store16(cpu, BASE_IO | 0xB6, 0, 0);
135 cpu->memory.store16(cpu, BASE_IO | 0xB8, 0, 0);
136 cpu->memory.store16(cpu, BASE_IO | 0xBA, 0, 0);
137 cpu->memory.store16(cpu, BASE_IO | 0xBC, 0, 0);
138 cpu->memory.store16(cpu, BASE_IO | 0xBE, 0, 0);
139 cpu->memory.store16(cpu, BASE_IO | 0xC0, 0, 0);
140 cpu->memory.store16(cpu, BASE_IO | 0xC2, 0, 0);
141 cpu->memory.store16(cpu, BASE_IO | 0xC4, 0, 0);
142 cpu->memory.store16(cpu, BASE_IO | 0xC6, 0, 0);
143 cpu->memory.store16(cpu, BASE_IO | 0xC8, 0, 0);
144 cpu->memory.store16(cpu, BASE_IO | 0xCA, 0, 0);
145 cpu->memory.store16(cpu, BASE_IO | 0xCC, 0, 0);
146 cpu->memory.store16(cpu, BASE_IO | 0xCE, 0, 0);
147 cpu->memory.store16(cpu, BASE_IO | 0xD0, 0, 0);
148 cpu->memory.store16(cpu, BASE_IO | 0xD2, 0, 0);
149 cpu->memory.store16(cpu, BASE_IO | 0xD4, 0, 0);
150 cpu->memory.store16(cpu, BASE_IO | 0xD6, 0, 0);
151 cpu->memory.store16(cpu, BASE_IO | 0xD8, 0, 0);
152 cpu->memory.store16(cpu, BASE_IO | 0xDA, 0, 0);
153 cpu->memory.store16(cpu, BASE_IO | 0xDC, 0, 0);
154 cpu->memory.store16(cpu, BASE_IO | 0xDE, 0, 0);
155 cpu->memory.store16(cpu, BASE_IO | 0x100, 0, 0);
156 cpu->memory.store16(cpu, BASE_IO | 0x102, 0, 0);
157 cpu->memory.store16(cpu, BASE_IO | 0x104, 0, 0);
158 cpu->memory.store16(cpu, BASE_IO | 0x106, 0, 0);
159 cpu->memory.store16(cpu, BASE_IO | 0x108, 0, 0);
160 cpu->memory.store16(cpu, BASE_IO | 0x10A, 0, 0);
161 cpu->memory.store16(cpu, BASE_IO | 0x10C, 0, 0);
162 cpu->memory.store16(cpu, BASE_IO | 0x10E, 0, 0);
163 cpu->memory.store16(cpu, BASE_IO | 0x200, 0, 0);
164 cpu->memory.store16(cpu, BASE_IO | 0x202, 0xFFFF, 0);
165 cpu->memory.store16(cpu, BASE_IO | 0x204, 0, 0);
166 cpu->memory.store16(cpu, BASE_IO | 0x208, 0, 0);
167 }
168}
169
170static void _BgAffineSet(struct GBA* gba) {
171 struct ARMCore* cpu = gba->cpu;
172 int i = cpu->gprs[2];
173 float ox, oy;
174 float cx, cy;
175 float sx, sy;
176 float theta;
177 int offset = cpu->gprs[0];
178 int destination = cpu->gprs[1];
179 float a, b, c, d;
180 float rx, ry;
181 while (i--) {
182 // [ sx 0 0 ] [ cos(theta) -sin(theta) 0 ] [ 1 0 cx - ox ] [ A B rx ]
183 // [ 0 sy 0 ] * [ sin(theta) cos(theta) 0 ] * [ 0 1 cy - oy ] = [ C D ry ]
184 // [ 0 0 1 ] [ 0 0 1 ] [ 0 0 1 ] [ 0 0 1 ]
185 ox = (int32_t) cpu->memory.load32(cpu, offset, 0) / 256.f;
186 oy = (int32_t) cpu->memory.load32(cpu, offset + 4, 0) / 256.f;
187 cx = (int16_t) cpu->memory.load16(cpu, offset + 8, 0);
188 cy = (int16_t) cpu->memory.load16(cpu, offset + 10, 0);
189 sx = (int16_t) cpu->memory.load16(cpu, offset + 12, 0) / 256.f;
190 sy = (int16_t) cpu->memory.load16(cpu, offset + 14, 0) / 256.f;
191 theta = (cpu->memory.load16(cpu, offset + 16, 0) >> 8) / 128.f * M_PI;
192 offset += 20;
193 // Rotation
194 a = d = cosf(theta);
195 b = c = sinf(theta);
196 // Scale
197 a *= sx;
198 b *= -sx;
199 c *= sy;
200 d *= sy;
201 // Translate
202 rx = ox - (a * cx + b * cy);
203 ry = oy - (c * cx + d * cy);
204 cpu->memory.store16(cpu, destination, a * 256, 0);
205 cpu->memory.store16(cpu, destination + 2, b * 256, 0);
206 cpu->memory.store16(cpu, destination + 4, c * 256, 0);
207 cpu->memory.store16(cpu, destination + 6, d * 256, 0);
208 cpu->memory.store32(cpu, destination + 8, rx * 256, 0);
209 cpu->memory.store32(cpu, destination + 12, ry * 256, 0);
210 destination += 16;
211 }
212}
213
214static void _ObjAffineSet(struct GBA* gba) {
215 struct ARMCore* cpu = gba->cpu;
216 int i = cpu->gprs[2];
217 float sx, sy;
218 float theta;
219 int offset = cpu->gprs[0];
220 int destination = cpu->gprs[1];
221 int diff = cpu->gprs[3];
222 float a, b, c, d;
223 while (i--) {
224 // [ sx 0 ] [ cos(theta) -sin(theta) ] [ A B ]
225 // [ 0 sy ] * [ sin(theta) cos(theta) ] = [ C D ]
226 sx = (int16_t) cpu->memory.load16(cpu, offset, 0) / 256.f;
227 sy = (int16_t) cpu->memory.load16(cpu, offset + 2, 0) / 256.f;
228 theta = (cpu->memory.load16(cpu, offset + 4, 0) >> 8) / 128.f * M_PI;
229 offset += 8;
230 // Rotation
231 a = d = cosf(theta);
232 b = c = sinf(theta);
233 // Scale
234 a *= sx;
235 b *= -sx;
236 c *= sy;
237 d *= sy;
238 cpu->memory.store16(cpu, destination, a * 256, 0);
239 cpu->memory.store16(cpu, destination + diff, b * 256, 0);
240 cpu->memory.store16(cpu, destination + diff * 2, c * 256, 0);
241 cpu->memory.store16(cpu, destination + diff * 3, d * 256, 0);
242 destination += diff * 4;
243 }
244}
245
246static void _MidiKey2Freq(struct GBA* gba) {
247 struct ARMCore* cpu = gba->cpu;
248
249 int oldRegion = gba->memory.activeRegion;
250 gba->memory.activeRegion = REGION_BIOS;
251 uint32_t key = cpu->memory.load32(cpu, cpu->gprs[0] + 4, 0);
252 gba->memory.activeRegion = oldRegion;
253
254 cpu->gprs[0] = key / powf(2, (180.f - cpu->gprs[1] - cpu->gprs[2] / 256.f) / 12.f);
255}
256
257static void _Div(struct GBA* gba, int32_t num, int32_t denom) {
258 struct ARMCore* cpu = gba->cpu;
259 if (denom != 0) {
260 div_t result = div(num, denom);
261 cpu->gprs[0] = result.quot;
262 cpu->gprs[1] = result.rem;
263 cpu->gprs[3] = abs(result.quot);
264 } else {
265 mLOG(GBA_BIOS, GAME_ERROR, "Attempting to divide %i by zero!", num);
266 // If abs(num) > 1, this should hang, but that would be painful to
267 // emulate in HLE, and no game will get into a state where it hangs...
268 cpu->gprs[0] = (num < 0) ? -1 : 1;
269 cpu->gprs[1] = num;
270 cpu->gprs[3] = 1;
271 }
272}
273
274static int16_t _ArcTan(int32_t i) {
275 int32_t a = -((i * i) >> 14);
276 int32_t b = ((0xA9 * a) >> 14) + 0x390;
277 b = ((b * a) >> 14) + 0x91C;
278 b = ((b * a) >> 14) + 0xFB6;
279 b = ((b * a) >> 14) + 0x16AA;
280 b = ((b * a) >> 14) + 0x2081;
281 b = ((b * a) >> 14) + 0x3651;
282 b = ((b * a) >> 14) + 0xA2F9;
283 return (i * b) >> 16;
284}
285
286static int16_t _ArcTan2(int32_t x, int32_t y) {
287 if (!y) {
288 if (x >= 0) {
289 return 0;
290 }
291 return 0x8000;
292 }
293 if (!x) {
294 if (y >= 0) {
295 return 0x4000;
296 }
297 return 0xC000;
298 }
299 if (y >= 0) {
300 if (x >= 0) {
301 if (x >= y) {
302 return _ArcTan((y << 14) / x);
303 }
304 } else if (-x >= y) {
305 return _ArcTan((y << 14) / x) + 0x8000;
306 }
307 return 0x4000 - _ArcTan((x << 14) / y);
308 } else {
309 if (x <= 0) {
310 if (-x > -y) {
311 return _ArcTan((y << 14) / x) + 0x8000;
312 }
313 } else if (x >= -y) {
314 return _ArcTan((y << 14) / x) + 0x10000;
315 }
316 return 0xC000 - _ArcTan((x << 14) / y);
317 }
318}
319
320void GBASwi16(struct ARMCore* cpu, int immediate) {
321 struct GBA* gba = (struct GBA*) cpu->master;
322 mLOG(GBA_BIOS, DEBUG, "SWI: %02X r0: %08X r1: %08X r2: %08X r3: %08X",
323 immediate, cpu->gprs[0], cpu->gprs[1], cpu->gprs[2], cpu->gprs[3]);
324
325 if (gba->memory.fullBios) {
326 ARMRaiseSWI(cpu);
327 return;
328 }
329 switch (immediate) {
330 case 0x0:
331 _SoftReset(gba);
332 break;
333 case 0x1:
334 _RegisterRamReset(gba);
335 break;
336 case 0x2:
337 GBAHalt(gba);
338 break;
339 case 0x3:
340 GBAStop(gba);
341 break;
342 case 0x05:
343 // VBlankIntrWait
344 // Fall through:
345 case 0x04:
346 // IntrWait
347 ARMRaiseSWI(cpu);
348 break;
349 case 0x6:
350 _Div(gba, cpu->gprs[0], cpu->gprs[1]);
351 break;
352 case 0x7:
353 _Div(gba, cpu->gprs[1], cpu->gprs[0]);
354 break;
355 case 0x8:
356 cpu->gprs[0] = sqrt((uint32_t) cpu->gprs[0]);
357 break;
358 case 0x9:
359 cpu->gprs[0] = _ArcTan(cpu->gprs[0]);
360 break;
361 case 0xA:
362 cpu->gprs[0] = (uint16_t) _ArcTan2(cpu->gprs[0], cpu->gprs[1]);
363 cpu->gprs[3] = 0x170;
364 break;
365 case 0xB:
366 case 0xC:
367 if (cpu->gprs[0] >> BASE_OFFSET < REGION_WORKING_RAM) {
368 mLOG(GBA_BIOS, GAME_ERROR, "Cannot CpuSet from BIOS");
369 break;
370 }
371 if (cpu->gprs[0] & (cpu->gprs[2] & (1 << 26) ? 3 : 1)) {
372 mLOG(GBA_BIOS, GAME_ERROR, "Misaligned CpuSet source");
373 }
374 if (cpu->gprs[1] & (cpu->gprs[2] & (1 << 26) ? 3 : 1)) {
375 mLOG(GBA_BIOS, GAME_ERROR, "Misaligned CpuSet destination");
376 }
377 ARMRaiseSWI(cpu);
378 break;
379 case 0xD:
380 cpu->gprs[0] = GBA_BIOS_CHECKSUM;
381 cpu->gprs[1] = 1;
382 cpu->gprs[3] = SIZE_BIOS;
383 break;
384 case 0xE:
385 _BgAffineSet(gba);
386 break;
387 case 0xF:
388 _ObjAffineSet(gba);
389 break;
390 case 0x10:
391 if (cpu->gprs[0] < BASE_WORKING_RAM) {
392 mLOG(GBA_BIOS, GAME_ERROR, "Bad BitUnPack source");
393 break;
394 }
395 switch (cpu->gprs[1] >> BASE_OFFSET) {
396 default:
397 mLOG(GBA_BIOS, GAME_ERROR, "Bad BitUnPack destination");
398 // Fall through
399 case REGION_WORKING_RAM:
400 case REGION_WORKING_IRAM:
401 case REGION_VRAM:
402 _unBitPack(gba);
403 break;
404 }
405 break;
406 case 0x11:
407 case 0x12:
408 if (cpu->gprs[0] < BASE_WORKING_RAM) {
409 mLOG(GBA_BIOS, GAME_ERROR, "Bad LZ77 source");
410 break;
411 }
412 switch (cpu->gprs[1] >> BASE_OFFSET) {
413 default:
414 mLOG(GBA_BIOS, GAME_ERROR, "Bad LZ77 destination");
415 // Fall through
416 case REGION_WORKING_RAM:
417 case REGION_WORKING_IRAM:
418 case REGION_VRAM:
419 _unLz77(gba, immediate == 0x11 ? 1 : 2);
420 break;
421 }
422 break;
423 case 0x13:
424 if (cpu->gprs[0] < BASE_WORKING_RAM) {
425 mLOG(GBA_BIOS, GAME_ERROR, "Bad Huffman source");
426 break;
427 }
428 switch (cpu->gprs[1] >> BASE_OFFSET) {
429 default:
430 mLOG(GBA_BIOS, GAME_ERROR, "Bad Huffman destination");
431 // Fall through
432 case REGION_WORKING_RAM:
433 case REGION_WORKING_IRAM:
434 case REGION_VRAM:
435 _unHuffman(gba);
436 break;
437 }
438 break;
439 case 0x14:
440 case 0x15:
441 if (cpu->gprs[0] < BASE_WORKING_RAM) {
442 mLOG(GBA_BIOS, GAME_ERROR, "Bad RL source");
443 break;
444 }
445 switch (cpu->gprs[1] >> BASE_OFFSET) {
446 default:
447 mLOG(GBA_BIOS, GAME_ERROR, "Bad RL destination");
448 // Fall through
449 case REGION_WORKING_RAM:
450 case REGION_WORKING_IRAM:
451 case REGION_VRAM:
452 _unRl(gba, immediate == 0x14 ? 1 : 2);
453 break;
454 }
455 break;
456 case 0x16:
457 case 0x17:
458 case 0x18:
459 if (cpu->gprs[0] < BASE_WORKING_RAM) {
460 mLOG(GBA_BIOS, GAME_ERROR, "Bad UnFilter source");
461 break;
462 }
463 switch (cpu->gprs[1] >> BASE_OFFSET) {
464 default:
465 mLOG(GBA_BIOS, GAME_ERROR, "Bad UnFilter destination");
466 // Fall through
467 case REGION_WORKING_RAM:
468 case REGION_WORKING_IRAM:
469 case REGION_VRAM:
470 _unFilter(gba, immediate == 0x18 ? 2 : 1, immediate == 0x16 ? 1 : 2);
471 break;
472 }
473 break;
474 case 0x19:
475 // SoundBias is mostly meaningless here
476 mLOG(GBA_BIOS, STUB, "Stub software interrupt: SoundBias (19)");
477 break;
478 case 0x1F:
479 _MidiKey2Freq(gba);
480 break;
481 default:
482 mLOG(GBA_BIOS, STUB, "Stub software interrupt: %02X", immediate);
483 }
484 gba->memory.biosPrefetch = 0xE3A02004;
485}
486
487void GBASwi32(struct ARMCore* cpu, int immediate) {
488 GBASwi16(cpu, immediate >> 16);
489}
490
491uint32_t GBAChecksum(uint32_t* memory, size_t size) {
492 size_t i;
493 uint32_t sum = 0;
494 for (i = 0; i < size; i += 4) {
495 sum += memory[i >> 2];
496 }
497 return sum;
498}
499
500static void _unLz77(struct GBA* gba, int width) {
501 struct ARMCore* cpu = gba->cpu;
502 uint32_t source = cpu->gprs[0];
503 uint32_t dest = cpu->gprs[1];
504 int remaining = (cpu->memory.load32(cpu, source, 0) & 0xFFFFFF00) >> 8;
505 // We assume the signature byte (0x10) is correct
506 int blockheader = 0; // Some compilers warn if this isn't set, even though it's trivially provably always set
507 source += 4;
508 int blocksRemaining = 0;
509 uint32_t disp;
510 int bytes;
511 int byte;
512 int halfword = 0;
513 while (remaining > 0) {
514 if (blocksRemaining) {
515 if (blockheader & 0x80) {
516 // Compressed
517 int block = cpu->memory.load8(cpu, source + 1, 0) | (cpu->memory.load8(cpu, source, 0) << 8);
518 source += 2;
519 disp = dest - (block & 0x0FFF) - 1;
520 bytes = (block >> 12) + 3;
521 while (bytes-- && remaining) {
522 --remaining;
523 if (width == 2) {
524 byte = (int16_t) cpu->memory.load16(cpu, disp & ~1, 0);
525 if (dest & 1) {
526 byte >>= (disp & 1) * 8;
527 halfword |= byte << 8;
528 cpu->memory.store16(cpu, dest ^ 1, halfword, 0);
529 } else {
530 byte >>= (disp & 1) * 8;
531 halfword = byte & 0xFF;
532 }
533 } else {
534 byte = cpu->memory.load8(cpu, disp, 0);
535 cpu->memory.store8(cpu, dest, byte, 0);
536 }
537 ++disp;
538 ++dest;
539 }
540 } else {
541 // Uncompressed
542 byte = cpu->memory.load8(cpu, source, 0);
543 ++source;
544 if (width == 2) {
545 if (dest & 1) {
546 halfword |= byte << 8;
547 cpu->memory.store16(cpu, dest ^ 1, halfword, 0);
548 } else {
549 halfword = byte;
550 }
551 } else {
552 cpu->memory.store8(cpu, dest, byte, 0);
553 }
554 ++dest;
555 --remaining;
556 }
557 blockheader <<= 1;
558 --blocksRemaining;
559 } else {
560 blockheader = cpu->memory.load8(cpu, source, 0);
561 ++source;
562 blocksRemaining = 8;
563 }
564 }
565 cpu->gprs[0] = source;
566 cpu->gprs[1] = dest;
567 cpu->gprs[3] = 0;
568}
569
570DECL_BITFIELD(HuffmanNode, uint8_t);
571DECL_BITS(HuffmanNode, Offset, 0, 6);
572DECL_BIT(HuffmanNode, RTerm, 6);
573DECL_BIT(HuffmanNode, LTerm, 7);
574
575static void _unHuffman(struct GBA* gba) {
576 struct ARMCore* cpu = gba->cpu;
577 uint32_t source = cpu->gprs[0] & 0xFFFFFFFC;
578 uint32_t dest = cpu->gprs[1];
579 uint32_t header = cpu->memory.load32(cpu, source, 0);
580 int remaining = header >> 8;
581 unsigned bits = header & 0xF;
582 if (bits == 0) {
583 mLOG(GBA_BIOS, GAME_ERROR, "Invalid Huffman bits");
584 bits = 8;
585 }
586 if (32 % bits || bits == 1) {
587 mLOG(GBA_BIOS, STUB, "Unimplemented unaligned Huffman");
588 return;
589 }
590 // We assume the signature byte (0x20) is correct
591 int treesize = (cpu->memory.load8(cpu, source + 4, 0) << 1) + 1;
592 int block = 0;
593 uint32_t treeBase = source + 5;
594 source += 5 + treesize;
595 uint32_t nPointer = treeBase;
596 HuffmanNode node;
597 int bitsRemaining;
598 int readBits;
599 int bitsSeen = 0;
600 node = cpu->memory.load8(cpu, nPointer, 0);
601 while (remaining > 0) {
602 uint32_t bitstream = cpu->memory.load32(cpu, source, 0);
603 source += 4;
604 for (bitsRemaining = 32; bitsRemaining > 0 && remaining > 0; --bitsRemaining, bitstream <<= 1) {
605 uint32_t next = (nPointer & ~1) + HuffmanNodeGetOffset(node) * 2 + 2;
606 if (bitstream & 0x80000000) {
607 // Go right
608 if (HuffmanNodeIsRTerm(node)) {
609 readBits = cpu->memory.load8(cpu, next + 1, 0);
610 } else {
611 nPointer = next + 1;
612 node = cpu->memory.load8(cpu, nPointer, 0);
613 continue;
614 }
615 } else {
616 // Go left
617 if (HuffmanNodeIsLTerm(node)) {
618 readBits = cpu->memory.load8(cpu, next, 0);
619 } else {
620 nPointer = next;
621 node = cpu->memory.load8(cpu, nPointer, 0);
622 continue;
623 }
624 }
625
626 block |= (readBits & ((1 << bits) - 1)) << bitsSeen;
627 bitsSeen += bits;
628 nPointer = treeBase;
629 node = cpu->memory.load8(cpu, nPointer, 0);
630 if (bitsSeen == 32) {
631 bitsSeen = 0;
632 cpu->memory.store32(cpu, dest, block, 0);
633 dest += 4;
634 remaining -= 4;
635 block = 0;
636 }
637 }
638 }
639 cpu->gprs[0] = source;
640 cpu->gprs[1] = dest;
641}
642
643static void _unRl(struct GBA* gba, int width) {
644 struct ARMCore* cpu = gba->cpu;
645 uint32_t source = cpu->gprs[0];
646 int remaining = (cpu->memory.load32(cpu, source & 0xFFFFFFFC, 0) & 0xFFFFFF00) >> 8;
647 int padding = (4 - remaining) & 0x3;
648 // We assume the signature byte (0x30) is correct
649 int blockheader;
650 int block;
651 source += 4;
652 uint32_t dest = cpu->gprs[1];
653 int halfword = 0;
654 while (remaining > 0) {
655 blockheader = cpu->memory.load8(cpu, source, 0);
656 ++source;
657 if (blockheader & 0x80) {
658 // Compressed
659 blockheader &= 0x7F;
660 blockheader += 3;
661 block = cpu->memory.load8(cpu, source, 0);
662 ++source;
663 while (blockheader-- && remaining) {
664 --remaining;
665 if (width == 2) {
666 if (dest & 1) {
667 halfword |= block << 8;
668 cpu->memory.store16(cpu, dest ^ 1, halfword, 0);
669 } else {
670 halfword = block;
671 }
672 } else {
673 cpu->memory.store8(cpu, dest, block, 0);
674 }
675 ++dest;
676 }
677 } else {
678 // Uncompressed
679 blockheader++;
680 while (blockheader-- && remaining) {
681 --remaining;
682 int byte = cpu->memory.load8(cpu, source, 0);
683 ++source;
684 if (width == 2) {
685 if (dest & 1) {
686 halfword |= byte << 8;
687 cpu->memory.store16(cpu, dest ^ 1, halfword, 0);
688 } else {
689 halfword = byte;
690 }
691 } else {
692 cpu->memory.store8(cpu, dest, byte, 0);
693 }
694 ++dest;
695 }
696 }
697 }
698 if (width == 2) {
699 if (dest & 1) {
700 --padding;
701 ++dest;
702 }
703 for (; padding > 0; padding -= 2, dest += 2) {
704 cpu->memory.store16(cpu, dest, 0, 0);
705 }
706 } else {
707 while (padding--) {
708 cpu->memory.store8(cpu, dest, 0, 0);
709 ++dest;
710 }
711 }
712 cpu->gprs[0] = source;
713 cpu->gprs[1] = dest;
714}
715
716static void _unFilter(struct GBA* gba, int inwidth, int outwidth) {
717 struct ARMCore* cpu = gba->cpu;
718 uint32_t source = cpu->gprs[0] & 0xFFFFFFFC;
719 uint32_t dest = cpu->gprs[1];
720 uint32_t header = cpu->memory.load32(cpu, source, 0);
721 int remaining = header >> 8;
722 // We assume the signature nybble (0x8) is correct
723 uint16_t halfword = 0;
724 uint16_t old = 0;
725 source += 4;
726 while (remaining > 0) {
727 uint16_t new;
728 if (inwidth == 1) {
729 new = cpu->memory.load8(cpu, source, 0);
730 } else {
731 new = cpu->memory.load16(cpu, source, 0);
732 }
733 new += old;
734 if (outwidth > inwidth) {
735 halfword >>= 8;
736 halfword |= (new << 8);
737 if (source & 1) {
738 cpu->memory.store16(cpu, dest, halfword, 0);
739 dest += outwidth;
740 remaining -= outwidth;
741 }
742 } else if (outwidth == 1) {
743 cpu->memory.store8(cpu, dest, new, 0);
744 dest += outwidth;
745 remaining -= outwidth;
746 } else {
747 cpu->memory.store16(cpu, dest, new, 0);
748 dest += outwidth;
749 remaining -= outwidth;
750 }
751 old = new;
752 source += inwidth;
753 }
754 cpu->gprs[0] = source;
755 cpu->gprs[1] = dest;
756}
757
758static void _unBitPack(struct GBA* gba) {
759 struct ARMCore* cpu = gba->cpu;
760 uint32_t source = cpu->gprs[0];
761 uint32_t dest = cpu->gprs[1];
762 uint32_t info = cpu->gprs[2];
763 unsigned sourceLen = cpu->memory.load16(cpu, info, 0);
764 unsigned sourceWidth = cpu->memory.load8(cpu, info + 2, 0);
765 unsigned destWidth = cpu->memory.load8(cpu, info + 3, 0);
766 switch (sourceWidth) {
767 case 1:
768 case 2:
769 case 4:
770 case 8:
771 break;
772 default:
773 mLOG(GBA_BIOS, GAME_ERROR, "Bad BitUnPack source width: %u", sourceWidth);
774 return;
775 }
776 switch (destWidth) {
777 case 1:
778 case 2:
779 case 4:
780 case 8:
781 case 16:
782 case 32:
783 break;
784 default:
785 mLOG(GBA_BIOS, GAME_ERROR, "Bad BitUnPack destination width: %u", destWidth);
786 return;
787 }
788 uint32_t bias = cpu->memory.load32(cpu, info + 4, 0);
789 uint8_t in = 0;
790 uint32_t out = 0;
791 int bitsRemaining = 0;
792 int bitsEaten = 0;
793 while (sourceLen > 0) {
794 if (!bitsRemaining) {
795 in = cpu->memory.load8(cpu, source, 0);
796 bitsRemaining = 8;
797 ++source;
798 --sourceLen;
799 }
800 unsigned scaled = in & ((1 << sourceWidth) - 1);
801 in >>= sourceWidth;
802 if (scaled || bias & 0x80000000) {
803 scaled += bias & 0x7FFFFFFF;
804 scaled &= (1 << destWidth) - 1;
805 }
806 bitsRemaining -= sourceWidth;
807 out |= scaled << bitsEaten;
808 bitsEaten += destWidth;
809 if (bitsEaten == 32) {
810 cpu->memory.store32(cpu, dest, out, 0);
811 bitsEaten = 0;
812 out = 0;
813 dest += 4;
814 }
815 }
816}