src/gba/gba-bios.c (view raw)
1#include "gba-bios.h"
2
3#include "gba.h"
4#include "gba-io.h"
5#include "gba-memory.h"
6
7const uint32_t GBA_BIOS_CHECKSUM = 0xBAAE187F;
8const uint32_t GBA_DS_BIOS_CHECKSUM = 0xBAAE1880;
9
10static void _unLz77(struct GBAMemory* memory, uint32_t source, uint8_t* dest);
11static void _unHuffman(struct GBAMemory* memory, uint32_t source, uint32_t* dest);
12static void _unRl(struct GBAMemory* memory, uint32_t source, uint8_t* dest);
13
14static void _RegisterRamReset(struct GBA* gba) {
15 uint32_t registers = gba->cpu.gprs[0];
16 (void)(registers);
17 GBALog(gba, GBA_LOG_STUB, "RegisterRamReset unimplemented");
18}
19
20static void _CpuSet(struct GBA* gba) {
21 uint32_t source = gba->cpu.gprs[0];
22 uint32_t dest = gba->cpu.gprs[1];
23 uint32_t mode = gba->cpu.gprs[2];
24 int count = mode & 0x000FFFFF;
25 int fill = mode & 0x01000000;
26 int wordsize = (mode & 0x04000000) ? 4 : 2;
27 int i;
28 if (fill) {
29 if (wordsize == 4) {
30 source &= 0xFFFFFFFC;
31 dest &= 0xFFFFFFFC;
32 int32_t word = gba->memory.d.load32(&gba->memory.d, source, &gba->cpu.cycles);
33 for (i = 0; i < count; ++i) {
34 gba->memory.d.store32(&gba->memory.d, dest + (i << 2), word, &gba->cpu.cycles);
35 gba->board.d.processEvents(&gba->board.d);
36 }
37 } else {
38 source &= 0xFFFFFFFE;
39 dest &= 0xFFFFFFFE;
40 uint16_t word = gba->memory.d.load16(&gba->memory.d, source, &gba->cpu.cycles);
41 for (i = 0; i < count; ++i) {
42 gba->memory.d.store16(&gba->memory.d, dest + (i << 1), word, &gba->cpu.cycles);
43 gba->board.d.processEvents(&gba->board.d);
44 }
45 }
46 } else {
47 if (wordsize == 4) {
48 source &= 0xFFFFFFFC;
49 dest &= 0xFFFFFFFC;
50 for (i = 0; i < count; ++i) {
51 int32_t word = gba->memory.d.load32(&gba->memory.d, source + (i << 2), &gba->cpu.cycles);
52 gba->memory.d.store32(&gba->memory.d, dest + (i << 2), word, &gba->cpu.cycles);
53 gba->board.d.processEvents(&gba->board.d);
54 }
55 } else {
56 source &= 0xFFFFFFFE;
57 dest &= 0xFFFFFFFE;
58 for (i = 0; i < count; ++i) {
59 uint16_t word = gba->memory.d.load16(&gba->memory.d, source + (i << 1), &gba->cpu.cycles);
60 gba->memory.d.store16(&gba->memory.d, dest + (i << 1), word, &gba->cpu.cycles);
61 gba->board.d.processEvents(&gba->board.d);
62 }
63 }
64 }
65}
66
67static void _FastCpuSet(struct GBA* gba) {
68 uint32_t source = gba->cpu.gprs[0] & 0xFFFFFFFC;
69 uint32_t dest = gba->cpu.gprs[1] & 0xFFFFFFFC;
70 uint32_t mode = gba->cpu.gprs[2];
71 int count = mode & 0x000FFFFF;
72 int storeCycles = gba->memory.d.waitMultiple(&gba->memory.d, dest, 4);
73 count = ((count + 7) >> 3) << 3;
74 int i;
75 if (mode & 0x01000000) {
76 int32_t word = gba->memory.d.load32(&gba->memory.d, source, &gba->cpu.cycles);
77 for (i = 0; i < count; i += 4) {
78 gba->memory.d.store32(&gba->memory.d, dest + ((i + 0) << 2), word, 0);
79 gba->memory.d.store32(&gba->memory.d, dest + ((i + 1) << 2), word, 0);
80 gba->memory.d.store32(&gba->memory.d, dest + ((i + 2) << 2), word, 0);
81 gba->memory.d.store32(&gba->memory.d, dest + ((i + 3) << 2), word, 0);
82 gba->cpu.cycles += storeCycles;
83 gba->board.d.processEvents(&gba->board.d);
84 }
85 } else {
86 int loadCycles = gba->memory.d.waitMultiple(&gba->memory.d, source, 4);
87 for (i = 0; i < count; i += 4) {
88 int32_t word0 = gba->memory.d.load32(&gba->memory.d, source + ((i + 0) << 2), 0);
89 int32_t word1 = gba->memory.d.load32(&gba->memory.d, source + ((i + 1) << 2), 0);
90 int32_t word2 = gba->memory.d.load32(&gba->memory.d, source + ((i + 2) << 2), 0);
91 int32_t word3 = gba->memory.d.load32(&gba->memory.d, source + ((i + 3) << 2), 0);
92 gba->cpu.cycles += loadCycles;
93 gba->board.d.processEvents(&gba->board.d);
94 gba->memory.d.store32(&gba->memory.d, dest + ((i + 0) << 2), word0, 0);
95 gba->memory.d.store32(&gba->memory.d, dest + ((i + 1) << 2), word1, 0);
96 gba->memory.d.store32(&gba->memory.d, dest + ((i + 2) << 2), word2, 0);
97 gba->memory.d.store32(&gba->memory.d, dest + ((i + 3) << 2), word3, 0);
98 gba->cpu.cycles += storeCycles;
99 gba->board.d.processEvents(&gba->board.d);
100 }
101 }
102}
103
104static void _BgAffineSet(struct GBA* gba) {
105 int i = gba->cpu.gprs[2];
106 float ox, oy;
107 float cx, cy;
108 float sx, sy;
109 float theta;
110 int offset = gba->cpu.gprs[0];
111 int destination = gba->cpu.gprs[1];
112 int diff = gba->cpu.gprs[3];
113 (void)(diff); // Are we supposed to use this?
114 float a, b, c, d;
115 float rx, ry;
116 while (i--) {
117 // [ sx 0 0 ] [ cos(theta) -sin(theta) 0 ] [ 1 0 cx - ox ] [ A B rx ]
118 // [ 0 sy 0 ] * [ sin(theta) cos(theta) 0 ] * [ 0 1 cy - oy ] = [ C D ry ]
119 // [ 0 0 1 ] [ 0 0 1 ] [ 0 0 1 ] [ 0 0 1 ]
120 ox = gba->memory.d.load32(&gba->memory.d, offset, 0) / 256.f;
121 oy = gba->memory.d.load32(&gba->memory.d, offset + 4, 0) / 256.f;
122 cx = gba->memory.d.load16(&gba->memory.d, offset + 8, 0);
123 cy = gba->memory.d.load16(&gba->memory.d, offset + 10, 0);
124 sx = gba->memory.d.load16(&gba->memory.d, offset + 12, 0) / 256.f;
125 sy = gba->memory.d.load16(&gba->memory.d, offset + 14, 0) / 256.f;
126 theta = (gba->memory.d.loadU16(&gba->memory.d, offset + 16, 0) >> 8) / 128.f * M_PI;
127 offset += 20;
128 // Rotation
129 a = d = cosf(theta);
130 b = c = sinf(theta);
131 // Scale
132 a *= sx;
133 b *= -sx;
134 c *= sy;
135 d *= sy;
136 // Translate
137 rx = ox - (a * cx + b * cy);
138 ry = oy - (c * cx + d * cy);
139 gba->memory.d.store16(&gba->memory.d, destination, a * 256, 0);
140 gba->memory.d.store16(&gba->memory.d, destination + 2, b * 256, 0);
141 gba->memory.d.store16(&gba->memory.d, destination + 4, c * 256, 0);
142 gba->memory.d.store16(&gba->memory.d, destination + 6, d * 256, 0);
143 gba->memory.d.store32(&gba->memory.d, destination + 8, rx * 256, 0);
144 gba->memory.d.store32(&gba->memory.d, destination + 12, ry * 256, 0);
145 destination += 16;
146 }
147}
148
149static void _ObjAffineSet(struct GBA* gba) {
150 int i = gba->cpu.gprs[2];
151 float sx, sy;
152 float theta;
153 int offset = gba->cpu.gprs[0];
154 int destination = gba->cpu.gprs[1];
155 int diff = gba->cpu.gprs[3];
156 float a, b, c, d;
157 while (i--) {
158 // [ sx 0 ] [ cos(theta) -sin(theta) ] [ A B ]
159 // [ 0 sy ] * [ sin(theta) cos(theta) ] = [ C D ]
160 sx = gba->memory.d.load16(&gba->memory.d, offset, 0) / 256.f;
161 sy = gba->memory.d.load16(&gba->memory.d, offset + 2, 0) / 256.f;
162 theta = (gba->memory.d.loadU16(&gba->memory.d, offset + 4, 0) >> 8) / 128.f * M_PI;
163 offset += 6;
164 // Rotation
165 a = d = cosf(theta);
166 b = c = sinf(theta);
167 // Scale
168 a *= sx;
169 b *= -sx;
170 c *= sy;
171 d *= sy;
172 gba->memory.d.store16(&gba->memory.d, destination, a * 256, 0);
173 gba->memory.d.store16(&gba->memory.d, destination + diff, b * 256, 0);
174 gba->memory.d.store16(&gba->memory.d, destination + diff * 2, c * 256, 0);
175 gba->memory.d.store16(&gba->memory.d, destination + diff * 3, d * 256, 0);
176 destination += diff * 4;
177 }
178}
179
180static void _MidiKey2Freq(struct GBA* gba) {
181 uint32_t key = gba->memory.d.load32(&gba->memory.d, gba->cpu.gprs[0] + 4, 0);
182 gba->cpu.gprs[0] = key / powf(2, (180.f - gba->cpu.gprs[1] - gba->cpu.gprs[2] / 256.f) / 12.f);
183}
184
185void GBASwi16(struct ARMBoard* board, int immediate) {
186 struct GBA* gba = ((struct GBABoard*) board)->p;
187 if (gba->memory.fullBios) {
188 ARMRaiseSWI(&gba->cpu);
189 return;
190 }
191 switch (immediate) {
192 case 0x1:
193 _RegisterRamReset(gba);
194 break;
195 case 0x2:
196 GBAHalt(gba);
197 break;
198 case 0x05:
199 // VBlankIntrWait
200 gba->cpu.gprs[0] = 1;
201 gba->cpu.gprs[1] = 1;
202 // Fall through:
203 case 0x04:
204 // IntrWait
205 gba->memory.io[REG_IME >> 1] = 1;
206 if (!gba->cpu.gprs[0] && gba->memory.io[REG_IF >> 1] & gba->cpu.gprs[1]) {
207 break;
208 }
209 gba->memory.io[REG_IF >> 1] = 0;
210 ARMRaiseSWI(&gba->cpu);
211 break;
212 case 0x6:
213 {
214 div_t result = div(gba->cpu.gprs[0], gba->cpu.gprs[1]);
215 gba->cpu.gprs[0] = result.quot;
216 gba->cpu.gprs[1] = result.rem;
217 gba->cpu.gprs[3] = abs(result.quot);
218 }
219 break;
220 case 0x7:
221 {
222 div_t result = div(gba->cpu.gprs[1], gba->cpu.gprs[0]);
223 gba->cpu.gprs[0] = result.quot;
224 gba->cpu.gprs[1] = result.rem;
225 gba->cpu.gprs[3] = abs(result.quot);
226 }
227 break;
228 case 0x8:
229 gba->cpu.gprs[0] = sqrt(gba->cpu.gprs[0]);
230 break;
231 case 0xA:
232 gba->cpu.gprs[0] = atan2f(gba->cpu.gprs[1] / 16384.f, gba->cpu.gprs[0] / 16384.f) / (2 * M_PI) * 0x10000;
233 break;
234 case 0xB:
235 _CpuSet(gba);
236 break;
237 case 0xC:
238 _FastCpuSet(gba);
239 break;
240 case 0xD:
241 gba->cpu.gprs[0] = GBAChecksum(gba->memory.bios, SIZE_BIOS);
242 case 0xE:
243 _BgAffineSet(gba);
244 break;
245 case 0xF:
246 _ObjAffineSet(gba);
247 break;
248 case 0x11:
249 case 0x12:
250 if (gba->cpu.gprs[0] < BASE_WORKING_RAM) {
251 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad LZ77 source");
252 break;
253 }
254 switch (gba->cpu.gprs[1] >> BASE_OFFSET) {
255 case REGION_WORKING_RAM:
256 _unLz77(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.wram)[(gba->cpu.gprs[1] & (SIZE_WORKING_RAM - 1))]);
257 break;
258 case REGION_WORKING_IRAM:
259 _unLz77(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.iwram)[(gba->cpu.gprs[1] & (SIZE_WORKING_IRAM - 1))]);
260 break;
261 case REGION_VRAM:
262 _unLz77(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->video.renderer->vram)[(gba->cpu.gprs[1] & 0x0001FFFF)]);
263 break;
264 default:
265 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad LZ77 destination");
266 break;
267 }
268 break;
269 case 0x13:
270 if (gba->cpu.gprs[0] < BASE_WORKING_RAM) {
271 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad Huffman source");
272 break;
273 }
274 switch (gba->cpu.gprs[1] >> BASE_OFFSET) {
275 case REGION_WORKING_RAM:
276 _unHuffman(&gba->memory, gba->cpu.gprs[0], &((uint32_t*) gba->memory.wram)[(gba->cpu.gprs[1] & (SIZE_WORKING_RAM - 3)) >> 2]);
277 break;
278 case REGION_WORKING_IRAM:
279 _unHuffman(&gba->memory, gba->cpu.gprs[0], &((uint32_t*) gba->memory.iwram)[(gba->cpu.gprs[1] & (SIZE_WORKING_IRAM - 3)) >> 2]);
280 break;
281 case REGION_VRAM:
282 _unHuffman(&gba->memory, gba->cpu.gprs[0], &((uint32_t*) gba->video.renderer->vram)[(gba->cpu.gprs[1] & 0x0001FFFC) >> 2]);
283 break;
284 default:
285 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad Huffman destination");
286 break;
287 }
288 break;
289 case 0x14:
290 case 0x15:
291 if (gba->cpu.gprs[0] < BASE_WORKING_RAM) {
292 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad RL source");
293 break;
294 }
295 switch (gba->cpu.gprs[1] >> BASE_OFFSET) {
296 case REGION_WORKING_RAM:
297 _unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.wram)[(gba->cpu.gprs[1] & (SIZE_WORKING_RAM - 1))]);
298 break;
299 case REGION_WORKING_IRAM:
300 _unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->memory.iwram)[(gba->cpu.gprs[1] & (SIZE_WORKING_IRAM - 1))]);
301 break;
302 case REGION_VRAM:
303 _unRl(&gba->memory, gba->cpu.gprs[0], &((uint8_t*) gba->video.renderer->vram)[(gba->cpu.gprs[1] & 0x0001FFFF)]);
304 break;
305 default:
306 GBALog(gba, GBA_LOG_GAME_ERROR, "Bad RL destination");
307 break;
308 }
309 break;
310 case 0x1F:
311 _MidiKey2Freq(gba);
312 break;
313 default:
314 GBALog(gba, GBA_LOG_STUB, "Stub software interrupt: %02x", immediate);
315 }
316}
317
318void GBASwi32(struct ARMBoard* board, int immediate) {
319 GBASwi16(board, immediate >> 16);
320}
321
322uint32_t GBAChecksum(uint32_t* memory, size_t size) {
323 size_t i;
324 uint32_t sum = 0;
325 for (i = 0; i < size; i += 4) {
326 sum += memory[i >> 2];
327 }
328 return sum;
329}
330
331static void _unLz77(struct GBAMemory* memory, uint32_t source, uint8_t* dest) {
332 int remaining = (memory->d.load32(&memory->d, source, 0) & 0xFFFFFF00) >> 8;
333 // We assume the signature byte (0x10) is correct
334 int blockheader;
335 uint32_t sPointer = source + 4;
336 uint8_t* dPointer = dest;
337 int blocksRemaining = 0;
338 int block;
339 uint8_t* disp;
340 int bytes;
341 while (remaining > 0) {
342 if (blocksRemaining) {
343 if (blockheader & 0x80) {
344 // Compressed
345 block = memory->d.loadU8(&memory->d, sPointer, 0) | (memory->d.loadU8(&memory->d, sPointer + 1, 0) << 8);
346 sPointer += 2;
347 disp = dPointer - (((block & 0x000F) << 8) | ((block & 0xFF00) >> 8)) - 1;
348 bytes = ((block & 0x00F0) >> 4) + 3;
349 while (bytes-- && remaining) {
350 --remaining;
351 *dPointer = *disp;
352 ++disp;
353 ++dPointer;
354 }
355 } else {
356 // Uncompressed
357 *dPointer = memory->d.loadU8(&memory->d, sPointer++, 0);
358 ++dPointer;
359 --remaining;
360 }
361 blockheader <<= 1;
362 --blocksRemaining;
363 } else {
364 blockheader = memory->d.loadU8(&memory->d, sPointer++, 0);
365 blocksRemaining = 8;
366 }
367 }
368}
369
370static void _unHuffman(struct GBAMemory* memory, uint32_t source, uint32_t* dest) {
371 source = source & 0xFFFFFFFC;
372 uint32_t header = memory->d.load32(&memory->d, source, 0);
373 int remaining = header >> 8;
374 int bits = header & 0xF;
375 if (32 % bits) {
376 GBALog(memory->p, GBA_LOG_STUB, "Unimplemented unaligned Huffman");
377 return;
378 }
379 int padding = (4 - remaining) & 0x3;
380 remaining &= 0xFFFFFFFC;
381 // We assume the signature byte (0x20) is correct
382 //var tree = [];
383 int treesize = (memory->d.loadU8(&memory->d, source + 4, 0) << 1) + 1;
384 int block = 0;
385 uint32_t treeBase = source + 5;
386 uint32_t sPointer = source + 5 + treesize;
387 uint32_t* dPointer = dest;
388 uint32_t nPointer = treeBase;
389 union HuffmanNode {
390 struct {
391 unsigned offset : 6;
392 unsigned rTerm : 1;
393 unsigned lTerm : 1;
394 };
395 uint8_t packed;
396 } node;
397 int bitsRemaining;
398 int readBits;
399 int bitsSeen = 0;
400 node.packed = memory->d.load8(&memory->d, nPointer, 0);
401 while (remaining > 0) {
402 uint32_t bitstream = memory->d.load32(&memory->d, sPointer, 0);
403 sPointer += 4;
404 for (bitsRemaining = 32; bitsRemaining > 0; --bitsRemaining, bitstream <<= 1) {
405 uint32_t next = (nPointer & ~1) + node.offset * 2 + 2;
406 if (bitstream & 0x80000000) {
407 // Go right
408 if (node.rTerm) {
409 readBits = memory->d.load8(&memory->d, next + 1, 0);
410 } else {
411 nPointer = next + 1;
412 node.packed = memory->d.load8(&memory->d, nPointer, 0);
413 continue;
414 }
415 } else {
416 // Go left
417 if (node.lTerm) {
418 readBits = memory->d.load8(&memory->d, next, 0);
419 } else {
420 nPointer = next;
421 node.packed = memory->d.load8(&memory->d, nPointer, 0);
422 continue;
423 }
424 }
425
426 block |= (readBits & ((1 << bits) - 1)) << bitsSeen;
427 bitsSeen += bits;
428 nPointer = treeBase;
429 node.packed = memory->d.load8(&memory->d, nPointer, 0);
430 if (bitsSeen == 32) {
431 bitsSeen = 0;
432 *dPointer = block;
433 ++dPointer;
434 remaining -= 4;
435 block = 0;
436 }
437 }
438
439 }
440 if (padding) {
441 *dPointer = block;
442 }
443}
444
445static void _unRl(struct GBAMemory* memory, uint32_t source, uint8_t* dest) {
446 source = source & 0xFFFFFFFC;
447 int remaining = (memory->d.load32(&memory->d, source, 0) & 0xFFFFFF00) >> 8;
448 int padding = (4 - remaining) & 0x3;
449 // We assume the signature byte (0x30) is correct
450 int blockheader;
451 int block;
452 uint32_t sPointer = source + 4;
453 uint8_t* dPointer = dest;
454 while (remaining > 0) {
455 blockheader = memory->d.loadU8(&memory->d, sPointer++, 0);
456 if (blockheader & 0x80) {
457 // Compressed
458 blockheader &= 0x7F;
459 blockheader += 3;
460 block = memory->d.loadU8(&memory->d, sPointer++, 0);
461 while (blockheader-- && remaining) {
462 --remaining;
463 *dPointer = block;
464 ++dPointer;
465 }
466 } else {
467 // Uncompressed
468 blockheader++;
469 while (blockheader-- && remaining) {
470 --remaining;
471 *dPointer = memory->d.loadU8(&memory->d, sPointer++, 0);
472 ++dPointer;
473 }
474 }
475 }
476 while (padding--) {
477 *dPointer = 0;
478 ++dPointer;
479 }
480}