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