main.c

   1 /*
   2  * TeensyTAS, TAS input player for MegaDrive
   3  * Copyright (c) 2014 notaz
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining
   6  * a copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sublicense, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be
  14  * included in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  20  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  21  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE.
  24  */
  25
  26 #include <stdint.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include "teensy3/core_pins.h"
  30 #include "teensy3/usb_seremu.h"
  31 #include "teensy3/usb_rawhid.h"
  32 #include "pkts.h"
  33
  34 #define noinline __attribute__((noinline))
  35
  36 // use power of 2
  37 #define STREAM_BUF_SIZE 512
  38 #define STREAM_BUF_MASK (512 - 1)
  39
  40 /* ?0SA 00DU, ?1CB RLDU */
  41 #define STREAM_EL_SZ 2
  42
  43 static struct {
  44         uint8_t stream_to[STREAM_BUF_SIZE][STREAM_EL_SZ];
  45         uint8_t stream_from[STREAM_BUF_SIZE][STREAM_EL_SZ];
  46         union {
  47                 uint8_t fixed_state[4];
  48                 uint32_t fixed_state32;
  49         };
  50         union {
  51                 uint8_t pending_state[4];
  52                 uint32_t pending_state32;
  53         };
  54         uint32_t stream_enable_to:1;
  55         uint32_t stream_enable_from:1;
  56         uint32_t stream_started:1;
  57         uint32_t stream_ended:1;
  58         uint32_t use_readinc:1;
  59         uint32_t use_pending:1;
  60         uint32_t frame_cnt;
  61         uint32_t edge_cnt;
  62         uint32_t t_i;
  63         uint32_t t_o;
  64         uint32_t f_i;
  65         uint32_t f_o;
  66 } g;
  67
  68 ssize_t _write(int fd, const void *buf, size_t nbyte)
  69 {
  70         char tbuf[64];
  71         int ret;
  72
  73         if (fd != 1 && fd != 2) {
  74                 snprintf(tbuf, sizeof(tbuf), "write to fd %d\n", fd);
  75                 usb_seremu_write(tbuf, strlen(tbuf));
  76         }
  77
  78         ret = usb_seremu_write(buf, nbyte);
  79         return ret < 0 ? ret : nbyte;
  80 }
  81
  82 void yield(void)
  83 {
  84 }
  85
  86 /* portb handles TH */
  87 static void portb_isr_fixed(void)
  88 {
  89         uint32_t isfr, th;
  90
  91         isfr = PORTB_ISFR;
  92         PORTB_ISFR = isfr;
  93         th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
  94
  95         GPIOD_PDOR = g.fixed_state[th];
  96         g.edge_cnt++;
  97 }
  98
  99 static noinline void do_to_step(void)
 100 {
 101         g.frame_cnt++;
 102
 103         g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
 104         if (g.t_o == g.t_i)
 105                 // done
 106                 attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
 107 }
 108
 109 static void portb_isr_do_to_inc(void)
 110 {
 111         uint32_t isfr, th;
 112
 113         isfr = PORTB_ISFR;
 114         PORTB_ISFR = isfr;
 115         th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
 116
 117         GPIOD_PDOR = g.stream_to[g.t_o][th];
 118         if (th)
 119                 do_to_step();
 120 }
 121
 122 static void portb_isr_do_to(void)
 123 {
 124         uint32_t isfr, th;
 125
 126         isfr = PORTB_ISFR;
 127         PORTB_ISFR = isfr;
 128         th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
 129
 130         GPIOD_PDOR = g.stream_to[g.t_o][th];
 131         g.edge_cnt++;
 132 }
 133
 134 static void portc_isr_nop(void)
 135 {
 136         uint32_t isfr;
 137
 138         isfr = PORTC_ISFR;
 139         PORTC_ISFR = isfr;
 140 }
 141
 142 // /vsync starts at line 235/259 (ntsc/pal), just as vcounter jumps back
 143 // we care when it comes out (/vsync goes high) after 3 lines at 238/262
 144 static void portc_isr_frameinc(void)
 145 {
 146         uint32_t isfr;
 147
 148         isfr = PORTC_ISFR;
 149         PORTC_ISFR = isfr;
 150
 151         g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
 152         if (g.t_o == g.t_i) {
 153                 attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
 154                 attachInterruptVector(IRQ_PORTC, portc_isr_nop);
 155         }
 156         g.frame_cnt++;
 157 }
 158
 159 /* "recording" data */
 160 static noinline void do_from_step(void)
 161 {
 162         uint32_t s;
 163
 164         // should hopefully give atomic fixed_state read..
 165         s = g.fixed_state32;
 166         g.fixed_state32 = g.pending_state32;
 167         g.stream_from[g.f_i][0] = s;
 168         g.stream_from[g.f_i][1] = s >> 8;
 169         g.f_i = (g.f_i + 1) & STREAM_BUF_MASK;
 170 }
 171
 172 static void portb_isr_fixed_do_from(void)
 173 {
 174         uint32_t isfr, th;
 175
 176         isfr = PORTB_ISFR;
 177         PORTB_ISFR = isfr;
 178         th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
 179
 180         GPIOD_PDOR = g.fixed_state[th];
 181         if (th)
 182                 do_from_step();
 183         g.edge_cnt++;
 184 }
 185
 186 static void portc_isr_frameinc_do_from(void)
 187 {
 188         uint32_t isfr;
 189
 190         isfr = PORTC_ISFR;
 191         PORTC_ISFR = isfr;
 192
 193         do_from_step();
 194         g.frame_cnt++;
 195 }
 196
 197 static void choose_isrs(void)
 198 {
 199         if (g.stream_enable_to) {
 200                 if (g.use_readinc) {
 201                         attachInterruptVector(IRQ_PORTB, portb_isr_do_to_inc);
 202                         attachInterruptVector(IRQ_PORTC, portc_isr_nop);
 203                 }
 204                 else {
 205                         attachInterruptVector(IRQ_PORTB, portb_isr_do_to);
 206                         attachInterruptVector(IRQ_PORTC, portc_isr_frameinc);
 207                 }
 208         }
 209         else if (g.stream_enable_from) {
 210                 g.use_pending = 1;
 211                 if (g.use_readinc) {
 212                         attachInterruptVector(IRQ_PORTB,
 213                                                 portb_isr_fixed_do_from);
 214                         attachInterruptVector(IRQ_PORTC, portc_isr_nop);
 215                 }
 216                 else {
 217                         attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
 218                         attachInterruptVector(IRQ_PORTC,
 219                                               portc_isr_frameinc_do_from);
 220                 }
 221         }
 222 }
 223
 224 static void udelay(uint32_t us)
 225 {
 226         uint32_t start = micros();
 227
 228         while ((micros() - start) < us) {
 229                 asm volatile("nop; nop; nop; nop");
 230                 yield();
 231         }
 232 }
 233
 234 static void do_start_seq(void)
 235 {
 236         uint32_t edge_cnt_last;
 237         uint32_t edge_cnt;
 238         uint32_t start, t1, t2;
 239         int tout;
 240
 241         start = micros();
 242         edge_cnt = g.edge_cnt;
 243
 244         /* magic value */
 245         g.fixed_state[0] =
 246         g.fixed_state[1] = 0x25;
 247
 248         for (tout = 10000; tout > 0; tout--) {
 249                 edge_cnt_last = edge_cnt;
 250                 udelay(100);
 251                 edge_cnt = g.edge_cnt;
 252
 253                 if (edge_cnt != edge_cnt_last)
 254                         continue;
 255                 if (!(GPIOB_PDIR & CORE_PIN0_BITMASK))
 256                         break;
 257         }
 258
 259         g.fixed_state[0] = 0x33;
 260         g.fixed_state[1] = 0x3f;
 261         GPIOD_PDOR = 0x33;
 262
 263         t1 = micros();
 264         if (tout == 0) {
 265                 printf("start_seq timeout1, t=%u\n", t1 - start);
 266                 return;
 267         }
 268
 269         for (tout = 100000; tout > 0; tout--) {
 270                 udelay(1);
 271
 272                 if (GPIOB_PDIR & CORE_PIN0_BITMASK)
 273                         break;
 274         }
 275
 276         t2 = micros();
 277         if (tout == 0) {
 278                 printf("start_seq timeout2, t1=%u, t2=%u\n",
 279                         t1 - start, t2 - t1);
 280                 return;
 281         }
 282
 283         //printf(" t1=%u, t2=%u\n", t1 - start, t2 - t1);
 284
 285         if (g.stream_started) {
 286                 printf("got start_seq when already started\n");
 287                 return;
 288         }
 289
 290         if (!g.stream_enable_to && !g.stream_enable_from) {
 291                 printf("got start_seq, without enable from USB\n");
 292                 return;
 293         }
 294
 295         if (g.stream_enable_to && g.t_i == g.t_o) {
 296                 printf("got start_seq while stream_to is empty\n");
 297                 return;
 298         }
 299
 300         if (g.stream_enable_from && g.f_i != g.f_o) {
 301                 printf("got start_seq while stream_from is not empty\n");
 302                 return;
 303         }
 304
 305         __disable_irq();
 306         choose_isrs();
 307         g.stream_started = 1;
 308         __enable_irq();
 309 }
 310
 311 // callers must disable IRQs
 312 static void clear_state(void)
 313 {
 314         g.stream_enable_to = 0;
 315         g.stream_enable_from = 0;
 316         g.stream_started = 0;
 317         g.stream_ended = 0;
 318         g.use_readinc = 0;
 319         g.use_pending = 0;
 320         g.t_i = g.t_o = 0;
 321         g.f_i = g.f_o = 0;
 322         g.frame_cnt = 0;
 323         attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
 324         attachInterruptVector(IRQ_PORTC, portc_isr_nop);
 325 }
 326
 327 static int get_space_to(void)
 328 {
 329         return STREAM_BUF_SIZE - ((g.t_i - g.t_o) & STREAM_BUF_MASK);
 330 }
 331
 332 static int get_used_from(void)
 333 {
 334         return (g.f_i - g.f_o) & STREAM_BUF_MASK;
 335 }
 336
 337 static void do_usb(void *buf)
 338 {
 339         struct tas_pkt *pkt = buf;
 340         uint32_t t_i, i;
 341         int space;
 342
 343         switch (pkt->type) {
 344         case PKT_FIXED_STATE:
 345                 memcpy(&i, pkt->data, sizeof(i));
 346                 if (g.use_pending)
 347                         g.pending_state32 = i;
 348                 else
 349                         g.fixed_state32 = i;
 350                 break;
 351         case PKT_STREAM_ENABLE:
 352                 __disable_irq();
 353                 clear_state();
 354                 /* wait for start from MD */
 355                 g.stream_enable_to = pkt->enable.stream_to;
 356                 g.stream_enable_from = pkt->enable.stream_from;
 357                 g.use_readinc = pkt->enable.use_readinc;
 358                 if (pkt->enable.no_start_seq) {
 359                         GPIOD_PDOR = 0x3f;
 360                         choose_isrs();
 361                         g.stream_started = 1;
 362                 }
 363                 __enable_irq();
 364                 break;
 365         case PKT_STREAM_ABORT:
 366                 __disable_irq();
 367                 clear_state();
 368                 __enable_irq();
 369                 break;
 370         case PKT_STREAM_END:
 371                 g.stream_ended = 1;
 372                 printf("end of stream\n");
 373                 break;
 374         case PKT_STREAM_DATA_TO:
 375                 t_i = g.t_i;
 376                 space = get_space_to();
 377                 if (space <= pkt->size / STREAM_EL_SZ) {
 378                         printf("got data pkt while space=%d\n", space);
 379                         return;
 380                 }
 381                 for (i = 0; i < pkt->size / STREAM_EL_SZ; i++) {
 382                         memcpy(&g.stream_to[t_i++],
 383                                pkt->data + i * STREAM_EL_SZ,
 384                                STREAM_EL_SZ);
 385                         t_i &= STREAM_BUF_MASK;
 386                 }
 387                 g.t_i = t_i;
 388                 break;
 389         default:
 390                 printf("got unknown pkt type: %04x\n", pkt->type);
 391                 break;
 392         }
 393 }
 394
 395 int main(void)
 396 {
 397         uint32_t led_time = 0;
 398         uint32_t scheck_time = 0;
 399         uint32_t edge_cnt_last;
 400         uint32_t edge_cnt;
 401         uint8_t buf[64];
 402         int ret;
 403
 404         delay(1000); // wait for usb..
 405
 406         /* ?0SA 00DU, ?1CB RLDU */
 407         g.fixed_state[0] = 0x33;
 408         g.fixed_state[1] = 0x3f;
 409
 410         printf("starting, rawhid: %d\n", usb_rawhid_available());
 411
 412         // md pin   th tr tl  r  l  d  u vsync
 413         // md bit*   6  5  4  3  2  1  0
 414         // t bit   b16 d5 d4 d3 d2 d1 d0    c6
 415         // t pin     0 20  6  8  7 14  2    11
 416         // * - note: tl/tr mixed in most docs
 417         pinMode(0, INPUT);
 418         attachInterrupt(0, portb_isr_fixed, CHANGE);
 419         attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
 420         pinMode(11, INPUT);
 421         attachInterrupt(11, portc_isr_nop, RISING);
 422         attachInterruptVector(IRQ_PORTC, portc_isr_nop);
 423
 424         NVIC_SET_PRIORITY(IRQ_PORTB, 0);
 425         NVIC_SET_PRIORITY(IRQ_PORTC, 16);
 426         SCB_SHPR1 = SCB_SHPR2 = SCB_SHPR3 = 0x10101010;
 427
 428         pinMode( 2, OUTPUT);
 429         pinMode(14, OUTPUT);
 430         pinMode( 7, OUTPUT);
 431         pinMode( 8, OUTPUT);
 432         pinMode( 6, OUTPUT);
 433         pinMode(20, OUTPUT);
 434
 435         // led
 436         pinMode(13, OUTPUT);
 437
 438         // CORE_PIN0_PORTSET CORE_PIN0_BITMASK PORTB_PCR16
 439         printf("GPIOB PDDR, PDIR: %08x %08x\n", GPIOB_PDIR, GPIOB_PDDR);
 440         printf("GPIOC PDDR, PDIR: %08x %08x\n", GPIOC_PDIR, GPIOC_PDDR);
 441         printf("GPIOD PDDR, PDIR: %08x %08x\n", GPIOD_PDIR, GPIOD_PDDR);
 442         printf("PORTB_PCR16: %08x\n", PORTB_PCR16);
 443         printf("PORTC_PCR6:  %08x\n", PORTC_PCR6);
 444         printf("PORTD_PCR0:  %08x\n", PORTD_PCR0);
 445
 446         asm("mrs %0, BASEPRI" : "=r"(ret));
 447         printf("BASEPRI: %d, SHPR: %08x %08x %08x\n",
 448                 ret, SCB_SHPR1, SCB_SHPR2, SCB_SHPR3);
 449
 450         edge_cnt_last = g.edge_cnt;
 451
 452         while (1) {
 453                 struct tas_pkt pkt;
 454                 uint32_t now;
 455
 456                 while (g.stream_enable_to && !g.stream_ended
 457                   && get_space_to() > sizeof(pkt.data) / STREAM_EL_SZ)
 458                 {
 459                         if (g.t_i == g.t_o && g.frame_cnt != 0) {
 460                                 printf("underflow detected\n");
 461                                 g.stream_enable_to = 0;
 462                                 break;
 463                         }
 464
 465                         pkt.type = PKT_STREAM_REQ;
 466                         pkt.req.frame = g.frame_cnt;
 467
 468                         ret = usb_rawhid_send(&pkt, 1000);
 469                         if (ret != sizeof(pkt)) {
 470                                 printf("send STREAM_REQ: %d\n", ret);
 471                                 break;
 472                         }
 473
 474                         ret = usb_rawhid_recv(buf, 1000);
 475                         if (ret != 64)
 476                                 printf("usb_rawhid_recv/s: %d\n", ret);
 477                         else
 478                                 do_usb(buf);
 479                 }
 480
 481                 while (g.stream_enable_from && !g.stream_ended
 482                   && get_used_from() >= sizeof(pkt.data) / STREAM_EL_SZ)
 483                 {
 484                         uint32_t f_o;
 485                         int i;
 486
 487                         f_o = g.f_o;
 488                         for (i = 0; i < sizeof(pkt.data); i += STREAM_EL_SZ) {
 489                                 memcpy(pkt.data + i, &g.stream_from[f_o++],
 490                                         STREAM_EL_SZ);
 491                                 f_o &= STREAM_BUF_MASK;
 492                         }
 493                         g.f_o = f_o;
 494
 495                         pkt.type = PKT_STREAM_DATA_FROM;
 496                         pkt.size = i;
 497
 498                         ret = usb_rawhid_send(&pkt, 1000);
 499                         if (ret != sizeof(pkt)) {
 500                                 printf("send DATA_FROM: %d\n", ret);
 501                                 break;
 502                         }
 503                 }
 504
 505                 now = millis();
 506
 507                 // start condition check
 508                 if (now - scheck_time > 1000) {
 509                         edge_cnt = g.edge_cnt;
 510                         //printf("e: %d th: %d\n", edge_cnt - edge_cnt_last,
 511                         //      (GPIOB_PDIR >> CORE_PIN0_BIT) & 1);
 512                         if ((g.stream_enable_to || g.stream_enable_from)
 513                             && !g.stream_started
 514                             && edge_cnt - edge_cnt_last > 10000)
 515                         {
 516                                 do_start_seq();
 517                                 edge_cnt = g.edge_cnt;
 518                         }
 519                         edge_cnt_last = edge_cnt;
 520                         scheck_time = now;
 521                 }
 522
 523                 // led?
 524                 if (CORE_PIN13_PORTREG & CORE_PIN13_BITMASK) {
 525                         if ((int)(now - led_time) > 10)
 526                                 CORE_PIN13_PORTCLEAR = CORE_PIN13_BITMASK;
 527                 }
 528
 529                 // something on rawhid?
 530                 if (usb_rawhid_available() > 0)
 531                 {
 532                         ret = usb_rawhid_recv(buf, 20);
 533                         if (ret == 64) {
 534                                 led_time = millis();
 535                                 CORE_PIN13_PORTSET = CORE_PIN13_BITMASK;
 536
 537                                 do_usb(buf);
 538                         }
 539                         else {
 540                                 printf("usb_rawhid_recv: %d\n", ret);
 541                         }
 542                 }
 543         }
 544
 545         return 0;
 546 }