hw/pxa2xx_dma.c

   1 /*
   2  * Intel XScale PXA255/270 DMA controller.
   3  *
   4  * Copyright (c) 2006 Openedhand Ltd.
   5  * Copyright (c) 2006 Thorsten Zitterell
   6  * Written by Andrzej Zaborowski <balrog@zabor.org>
   7  *
   8  * This code is licenced under the GPL.
   9  */
  10
  11 #include "hw.h"
  12 #include "pxa.h"
  13
  14 typedef struct {
  15     target_phys_addr_t descr;
  16     target_phys_addr_t src;
  17     target_phys_addr_t dest;
  18     uint32_t cmd;
  19     uint32_t state;
  20     int request;
  21 } PXA2xxDMAChannel;
  22
  23 /* Allow the DMA to be used as a PIC.  */
  24 typedef void (*pxa2xx_dma_handler_t)(void *opaque, int irq, int level);
  25
  26 struct PXA2xxDMAState {
  27     pxa2xx_dma_handler_t handler;
  28     qemu_irq irq;
  29
  30     uint32_t stopintr;
  31     uint32_t eorintr;
  32     uint32_t rasintr;
  33     uint32_t startintr;
  34     uint32_t endintr;
  35
  36     uint32_t align;
  37     uint32_t pio;
  38
  39     int channels;
  40     PXA2xxDMAChannel *chan;
  41
  42     uint8_t *req;
  43
  44     /* Flag to avoid recursive DMA invocations.  */
  45     int running;
  46 };
  47
  48 #define PXA255_DMA_NUM_CHANNELS 16
  49 #define PXA27X_DMA_NUM_CHANNELS 32
  50
  51 #define PXA2XX_DMA_NUM_REQUESTS 75
  52
  53 #define DCSR0   0x0000  /* DMA Control / Status register for Channel 0 */
  54 #define DCSR31  0x007c  /* DMA Control / Status register for Channel 31 */
  55 #define DALGN   0x00a0  /* DMA Alignment register */
  56 #define DPCSR   0x00a4  /* DMA Programmed I/O Control Status register */
  57 #define DRQSR0  0x00e0  /* DMA DREQ<0> Status register */
  58 #define DRQSR1  0x00e4  /* DMA DREQ<1> Status register */
  59 #define DRQSR2  0x00e8  /* DMA DREQ<2> Status register */
  60 #define DINT    0x00f0  /* DMA Interrupt register */
  61 #define DRCMR0  0x0100  /* Request to Channel Map register 0 */
  62 #define DRCMR63 0x01fc  /* Request to Channel Map register 63 */
  63 #define D_CH0   0x0200  /* Channel 0 Descriptor start */
  64 #define DRCMR64 0x1100  /* Request to Channel Map register 64 */
  65 #define DRCMR74 0x1128  /* Request to Channel Map register 74 */
  66
  67 /* Per-channel register */
  68 #define DDADR   0x00
  69 #define DSADR   0x01
  70 #define DTADR   0x02
  71 #define DCMD    0x03
  72
  73 /* Bit-field masks */
  74 #define DRCMR_CHLNUM            0x1f
  75 #define DRCMR_MAPVLD            (1 << 7)
  76 #define DDADR_STOP              (1 << 0)
  77 #define DDADR_BREN              (1 << 1)
  78 #define DCMD_LEN                0x1fff
  79 #define DCMD_WIDTH(x)           (1 << ((((x) >> 14) & 3) - 1))
  80 #define DCMD_SIZE(x)            (4 << (((x) >> 16) & 3))
  81 #define DCMD_FLYBYT             (1 << 19)
  82 #define DCMD_FLYBYS             (1 << 20)
  83 #define DCMD_ENDIRQEN           (1 << 21)
  84 #define DCMD_STARTIRQEN         (1 << 22)
  85 #define DCMD_CMPEN              (1 << 25)
  86 #define DCMD_FLOWTRG            (1 << 28)
  87 #define DCMD_FLOWSRC            (1 << 29)
  88 #define DCMD_INCTRGADDR         (1 << 30)
  89 #define DCMD_INCSRCADDR         (1 << 31)
  90 #define DCSR_BUSERRINTR         (1 << 0)
  91 #define DCSR_STARTINTR          (1 << 1)
  92 #define DCSR_ENDINTR            (1 << 2)
  93 #define DCSR_STOPINTR           (1 << 3)
  94 #define DCSR_RASINTR            (1 << 4)
  95 #define DCSR_REQPEND            (1 << 8)
  96 #define DCSR_EORINT             (1 << 9)
  97 #define DCSR_CMPST              (1 << 10)
  98 #define DCSR_MASKRUN            (1 << 22)
  99 #define DCSR_RASIRQEN           (1 << 23)
 100 #define DCSR_CLRCMPST           (1 << 24)
 101 #define DCSR_SETCMPST           (1 << 25)
 102 #define DCSR_EORSTOPEN          (1 << 26)
 103 #define DCSR_EORJMPEN           (1 << 27)
 104 #define DCSR_EORIRQEN           (1 << 28)
 105 #define DCSR_STOPIRQEN          (1 << 29)
 106 #define DCSR_NODESCFETCH        (1 << 30)
 107 #define DCSR_RUN                (1 << 31)
 108
 109 static inline void pxa2xx_dma_update(PXA2xxDMAState *s, int ch)
 110 {
 111     if (ch >= 0) {
 112         if ((s->chan[ch].state & DCSR_STOPIRQEN) &&
 113                 (s->chan[ch].state & DCSR_STOPINTR))
 114             s->stopintr |= 1 << ch;
 115         else
 116             s->stopintr &= ~(1 << ch);
 117
 118         if ((s->chan[ch].state & DCSR_EORIRQEN) &&
 119                 (s->chan[ch].state & DCSR_EORINT))
 120             s->eorintr |= 1 << ch;
 121         else
 122             s->eorintr &= ~(1 << ch);
 123
 124         if ((s->chan[ch].state & DCSR_RASIRQEN) &&
 125                 (s->chan[ch].state & DCSR_RASINTR))
 126             s->rasintr |= 1 << ch;
 127         else
 128             s->rasintr &= ~(1 << ch);
 129
 130         if (s->chan[ch].state & DCSR_STARTINTR)
 131             s->startintr |= 1 << ch;
 132         else
 133             s->startintr &= ~(1 << ch);
 134
 135         if (s->chan[ch].state & DCSR_ENDINTR)
 136             s->endintr |= 1 << ch;
 137         else
 138             s->endintr &= ~(1 << ch);
 139     }
 140
 141     if (s->stopintr | s->eorintr | s->rasintr | s->startintr | s->endintr)
 142         qemu_irq_raise(s->irq);
 143     else
 144         qemu_irq_lower(s->irq);
 145 }
 146
 147 static inline void pxa2xx_dma_descriptor_fetch(
 148                 PXA2xxDMAState *s, int ch)
 149 {
 150     uint32_t desc[4];
 151     target_phys_addr_t daddr = s->chan[ch].descr & ~0xf;
 152     if ((s->chan[ch].descr & DDADR_BREN) && (s->chan[ch].state & DCSR_CMPST))
 153         daddr += 32;
 154
 155     cpu_physical_memory_read(daddr, (uint8_t *) desc, 16);
 156     s->chan[ch].descr = desc[DDADR];
 157     s->chan[ch].src = desc[DSADR];
 158     s->chan[ch].dest = desc[DTADR];
 159     s->chan[ch].cmd = desc[DCMD];
 160
 161     if (s->chan[ch].cmd & DCMD_FLOWSRC)
 162         s->chan[ch].src &= ~3;
 163     if (s->chan[ch].cmd & DCMD_FLOWTRG)
 164         s->chan[ch].dest &= ~3;
 165
 166     if (s->chan[ch].cmd & (DCMD_CMPEN | DCMD_FLYBYS | DCMD_FLYBYT))
 167         printf("%s: unsupported mode in channel %i\n", __FUNCTION__, ch);
 168
 169     if (s->chan[ch].cmd & DCMD_STARTIRQEN)
 170         s->chan[ch].state |= DCSR_STARTINTR;
 171 }
 172
 173 static void pxa2xx_dma_run(PXA2xxDMAState *s)
 174 {
 175     int c, srcinc, destinc;
 176     uint32_t n, size;
 177     uint32_t width;
 178     uint32_t length;
 179     uint8_t buffer[32];
 180     PXA2xxDMAChannel *ch;
 181
 182     if (s->running ++)
 183         return;
 184
 185     while (s->running) {
 186         s->running = 1;
 187         for (c = 0; c < s->channels; c ++) {
 188             ch = &s->chan[c];
 189
 190             while ((ch->state & DCSR_RUN) && !(ch->state & DCSR_STOPINTR)) {
 191                 /* Test for pending requests */
 192                 if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) && !ch->request)
 193                     break;
 194
 195                 length = ch->cmd & DCMD_LEN;
 196                 size = DCMD_SIZE(ch->cmd);
 197                 width = DCMD_WIDTH(ch->cmd);
 198
 199                 srcinc = (ch->cmd & DCMD_INCSRCADDR) ? width : 0;
 200                 destinc = (ch->cmd & DCMD_INCTRGADDR) ? width : 0;
 201
 202                 while (length) {
 203                     size = MIN(length, size);
 204
 205                     for (n = 0; n < size; n += width) {
 206                         cpu_physical_memory_read(ch->src, buffer + n, width);
 207                         ch->src += srcinc;
 208                     }
 209
 210                     for (n = 0; n < size; n += width) {
 211                         cpu_physical_memory_write(ch->dest, buffer + n, width);
 212                         ch->dest += destinc;
 213                     }
 214
 215                     length -= size;
 216
 217                     if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) &&
 218                             !ch->request) {
 219                         ch->state |= DCSR_EORINT;
 220                         if (ch->state & DCSR_EORSTOPEN)
 221                             ch->state |= DCSR_STOPINTR;
 222                         if ((ch->state & DCSR_EORJMPEN) &&
 223                                         !(ch->state & DCSR_NODESCFETCH))
 224                             pxa2xx_dma_descriptor_fetch(s, c);
 225                         break;
 226                     }
 227                 }
 228
 229                 ch->cmd = (ch->cmd & ~DCMD_LEN) | length;
 230
 231                 /* Is the transfer complete now? */
 232                 if (!length) {
 233                     if (ch->cmd & DCMD_ENDIRQEN)
 234                         ch->state |= DCSR_ENDINTR;
 235
 236                     if ((ch->state & DCSR_NODESCFETCH) ||
 237                                 (ch->descr & DDADR_STOP) ||
 238                                 (ch->state & DCSR_EORSTOPEN)) {
 239                         ch->state |= DCSR_STOPINTR;
 240                         ch->state &= ~DCSR_RUN;
 241
 242                         break;
 243                     }
 244
 245                     ch->state |= DCSR_STOPINTR;
 246                     break;
 247                 }
 248             }
 249         }
 250
 251         s->running --;
 252     }
 253 }
 254
 255 static uint32_t pxa2xx_dma_read(void *opaque, target_phys_addr_t offset)
 256 {
 257     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
 258     unsigned int channel;
 259
 260     switch (offset) {
 261     case DRCMR64 ... DRCMR74:
 262         offset -= DRCMR64 - DRCMR0 - (64 << 2);
 263         /* Fall through */
 264     case DRCMR0 ... DRCMR63:
 265         channel = (offset - DRCMR0) >> 2;
 266         return s->req[channel];
 267
 268     case DRQSR0:
 269     case DRQSR1:
 270     case DRQSR2:
 271         return 0;
 272
 273     case DCSR0 ... DCSR31:
 274         channel = offset >> 2;
 275         if (s->chan[channel].request)
 276             return s->chan[channel].state | DCSR_REQPEND;
 277         return s->chan[channel].state;
 278
 279     case DINT:
 280         return s->stopintr | s->eorintr | s->rasintr |
 281                 s->startintr | s->endintr;
 282
 283     case DALGN:
 284         return s->align;
 285
 286     case DPCSR:
 287         return s->pio;
 288     }
 289
 290     if (offset >= D_CH0 && offset < D_CH0 + (s->channels << 4)) {
 291         channel = (offset - D_CH0) >> 4;
 292         switch ((offset & 0x0f) >> 2) {
 293         case DDADR:
 294             return s->chan[channel].descr;
 295         case DSADR:
 296             return s->chan[channel].src;
 297         case DTADR:
 298             return s->chan[channel].dest;
 299         case DCMD:
 300             return s->chan[channel].cmd;
 301         }
 302     }
 303
 304     hw_error("%s: Bad offset 0x" TARGET_FMT_plx "\n", __FUNCTION__, offset);
 305     return 7;
 306 }
 307
 308 static void pxa2xx_dma_write(void *opaque,
 309                  target_phys_addr_t offset, uint32_t value)
 310 {
 311     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
 312     unsigned int channel;
 313
 314     switch (offset) {
 315     case DRCMR64 ... DRCMR74:
 316         offset -= DRCMR64 - DRCMR0 - (64 << 2);
 317         /* Fall through */
 318     case DRCMR0 ... DRCMR63:
 319         channel = (offset - DRCMR0) >> 2;
 320
 321         if (value & DRCMR_MAPVLD)
 322             if ((value & DRCMR_CHLNUM) > s->channels)
 323                 hw_error("%s: Bad DMA channel %i\n",
 324                          __FUNCTION__, value & DRCMR_CHLNUM);
 325
 326         s->req[channel] = value;
 327         break;
 328
 329     case DRQSR0:
 330     case DRQSR1:
 331     case DRQSR2:
 332         /* Nothing to do */
 333         break;
 334
 335     case DCSR0 ... DCSR31:
 336         channel = offset >> 2;
 337         s->chan[channel].state &= 0x0000071f & ~(value &
 338                         (DCSR_EORINT | DCSR_ENDINTR |
 339                          DCSR_STARTINTR | DCSR_BUSERRINTR));
 340         s->chan[channel].state |= value & 0xfc800000;
 341
 342         if (s->chan[channel].state & DCSR_STOPIRQEN)
 343             s->chan[channel].state &= ~DCSR_STOPINTR;
 344
 345         if (value & DCSR_NODESCFETCH) {
 346             /* No-descriptor-fetch mode */
 347             if (value & DCSR_RUN) {
 348                 s->chan[channel].state &= ~DCSR_STOPINTR;
 349                 pxa2xx_dma_run(s);
 350             }
 351         } else {
 352             /* Descriptor-fetch mode */
 353             if (value & DCSR_RUN) {
 354                 s->chan[channel].state &= ~DCSR_STOPINTR;
 355                 pxa2xx_dma_descriptor_fetch(s, channel);
 356                 pxa2xx_dma_run(s);
 357             }
 358         }
 359
 360         /* Shouldn't matter as our DMA is synchronous.  */
 361         if (!(value & (DCSR_RUN | DCSR_MASKRUN)))
 362             s->chan[channel].state |= DCSR_STOPINTR;
 363
 364         if (value & DCSR_CLRCMPST)
 365             s->chan[channel].state &= ~DCSR_CMPST;
 366         if (value & DCSR_SETCMPST)
 367             s->chan[channel].state |= DCSR_CMPST;
 368
 369         pxa2xx_dma_update(s, channel);
 370         break;
 371
 372     case DALGN:
 373         s->align = value;
 374         break;
 375
 376     case DPCSR:
 377         s->pio = value & 0x80000001;
 378         break;
 379
 380     default:
 381         if (offset >= D_CH0 && offset < D_CH0 + (s->channels << 4)) {
 382             channel = (offset - D_CH0) >> 4;
 383             switch ((offset & 0x0f) >> 2) {
 384             case DDADR:
 385                 s->chan[channel].descr = value;
 386                 break;
 387             case DSADR:
 388                 s->chan[channel].src = value;
 389                 break;
 390             case DTADR:
 391                 s->chan[channel].dest = value;
 392                 break;
 393             case DCMD:
 394                 s->chan[channel].cmd = value;
 395                 break;
 396             default:
 397                 goto fail;
 398             }
 399
 400             break;
 401         }
 402     fail:
 403         hw_error("%s: Bad offset " TARGET_FMT_plx "\n", __FUNCTION__, offset);
 404     }
 405 }
 406
 407 static uint32_t pxa2xx_dma_readbad(void *opaque, target_phys_addr_t offset)
 408 {
 409     hw_error("%s: Bad access width\n", __FUNCTION__);
 410     return 5;
 411 }
 412
 413 static void pxa2xx_dma_writebad(void *opaque,
 414                  target_phys_addr_t offset, uint32_t value)
 415 {
 416     hw_error("%s: Bad access width\n", __FUNCTION__);
 417 }
 418
 419 static CPUReadMemoryFunc * const pxa2xx_dma_readfn[] = {
 420     pxa2xx_dma_readbad,
 421     pxa2xx_dma_readbad,
 422     pxa2xx_dma_read
 423 };
 424
 425 static CPUWriteMemoryFunc * const pxa2xx_dma_writefn[] = {
 426     pxa2xx_dma_writebad,
 427     pxa2xx_dma_writebad,
 428     pxa2xx_dma_write
 429 };
 430
 431 static void pxa2xx_dma_save(QEMUFile *f, void *opaque)
 432 {
 433     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
 434     int i;
 435
 436     qemu_put_be32(f, s->channels);
 437
 438     qemu_put_be32s(f, &s->stopintr);
 439     qemu_put_be32s(f, &s->eorintr);
 440     qemu_put_be32s(f, &s->rasintr);
 441     qemu_put_be32s(f, &s->startintr);
 442     qemu_put_be32s(f, &s->endintr);
 443     qemu_put_be32s(f, &s->align);
 444     qemu_put_be32s(f, &s->pio);
 445
 446     qemu_put_buffer(f, s->req, PXA2XX_DMA_NUM_REQUESTS);
 447     for (i = 0; i < s->channels; i ++) {
 448         qemu_put_betl(f, s->chan[i].descr);
 449         qemu_put_betl(f, s->chan[i].src);
 450         qemu_put_betl(f, s->chan[i].dest);
 451         qemu_put_be32s(f, &s->chan[i].cmd);
 452         qemu_put_be32s(f, &s->chan[i].state);
 453         qemu_put_be32(f, s->chan[i].request);
 454     };
 455 }
 456
 457 static int pxa2xx_dma_load(QEMUFile *f, void *opaque, int version_id)
 458 {
 459     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
 460     int i;
 461
 462     if (qemu_get_be32(f) != s->channels)
 463         return -EINVAL;
 464
 465     qemu_get_be32s(f, &s->stopintr);
 466     qemu_get_be32s(f, &s->eorintr);
 467     qemu_get_be32s(f, &s->rasintr);
 468     qemu_get_be32s(f, &s->startintr);
 469     qemu_get_be32s(f, &s->endintr);
 470     qemu_get_be32s(f, &s->align);
 471     qemu_get_be32s(f, &s->pio);
 472
 473     qemu_get_buffer(f, s->req, PXA2XX_DMA_NUM_REQUESTS);
 474     for (i = 0; i < s->channels; i ++) {
 475         s->chan[i].descr = qemu_get_betl(f);
 476         s->chan[i].src = qemu_get_betl(f);
 477         s->chan[i].dest = qemu_get_betl(f);
 478         qemu_get_be32s(f, &s->chan[i].cmd);
 479         qemu_get_be32s(f, &s->chan[i].state);
 480         s->chan[i].request = qemu_get_be32(f);
 481     };
 482
 483     return 0;
 484 }
 485
 486 static PXA2xxDMAState *pxa2xx_dma_init(target_phys_addr_t base,
 487                 qemu_irq irq, int channels)
 488 {
 489     int i, iomemtype;
 490     PXA2xxDMAState *s;
 491     s = (PXA2xxDMAState *)
 492             qemu_mallocz(sizeof(PXA2xxDMAState));
 493
 494     s->channels = channels;
 495     s->chan = qemu_mallocz(sizeof(PXA2xxDMAChannel) * s->channels);
 496     s->irq = irq;
 497     s->handler = (pxa2xx_dma_handler_t) pxa2xx_dma_request;
 498     s->req = qemu_mallocz(sizeof(uint8_t) * PXA2XX_DMA_NUM_REQUESTS);
 499
 500     memset(s->chan, 0, sizeof(PXA2xxDMAChannel) * s->channels);
 501     for (i = 0; i < s->channels; i ++)
 502         s->chan[i].state = DCSR_STOPINTR;
 503
 504     memset(s->req, 0, sizeof(uint8_t) * PXA2XX_DMA_NUM_REQUESTS);
 505
 506     iomemtype = cpu_register_io_memory(pxa2xx_dma_readfn,
 507                     pxa2xx_dma_writefn, s);
 508     cpu_register_physical_memory(base, 0x00010000, iomemtype);
 509
 510     register_savevm("pxa2xx_dma", 0, 0, pxa2xx_dma_save, pxa2xx_dma_load, s);
 511
 512     return s;
 513 }
 514
 515 PXA2xxDMAState *pxa27x_dma_init(target_phys_addr_t base,
 516                 qemu_irq irq)
 517 {
 518     return pxa2xx_dma_init(base, irq, PXA27X_DMA_NUM_CHANNELS);
 519 }
 520
 521 PXA2xxDMAState *pxa255_dma_init(target_phys_addr_t base,
 522                 qemu_irq irq)
 523 {
 524     return pxa2xx_dma_init(base, irq, PXA255_DMA_NUM_CHANNELS);
 525 }
 526
 527 void pxa2xx_dma_request(PXA2xxDMAState *s, int req_num, int on)
 528 {
 529     int ch;
 530     if (req_num < 0 || req_num >= PXA2XX_DMA_NUM_REQUESTS)
 531         hw_error("%s: Bad DMA request %i\n", __FUNCTION__, req_num);
 532
 533     if (!(s->req[req_num] & DRCMR_MAPVLD))
 534         return;
 535     ch = s->req[req_num] & DRCMR_CHLNUM;
 536
 537     if (!s->chan[ch].request && on)
 538         s->chan[ch].state |= DCSR_RASINTR;
 539     else
 540         s->chan[ch].state &= ~DCSR_RASINTR;
 541     if (s->chan[ch].request && !on)
 542         s->chan[ch].state |= DCSR_EORINT;
 543
 544     s->chan[ch].request = on;
 545     if (on) {
 546         pxa2xx_dma_run(s);
 547         pxa2xx_dma_update(s, ch);
 548     }
 549 }