hw/misc/macio/mac_dbdma.c

   1 /*
   2  * PowerMac descriptor-based DMA emulation
   3  *
   4  * Copyright (c) 2005-2007 Fabrice Bellard
   5  * Copyright (c) 2007 Jocelyn Mayer
   6  * Copyright (c) 2009 Laurent Vivier
   7  *
   8  * some parts from linux-2.6.28, arch/powerpc/include/asm/dbdma.h
   9  *
  10  *   Definitions for using the Apple Descriptor-Based DMA controller
  11  *   in Power Macintosh computers.
  12  *
  13  *   Copyright (C) 1996 Paul Mackerras.
  14  *
  15  * some parts from mol 0.9.71
  16  *
  17  *   Descriptor based DMA emulation
  18  *
  19  *   Copyright (C) 1998-2004 Samuel Rydh (samuel@ibrium.se)
  20  *
  21  * Permission is hereby granted, free of charge, to any person obtaining a copy
  22  * of this software and associated documentation files (the "Software"), to deal
  23  * in the Software without restriction, including without limitation the rights
  24  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  25  * copies of the Software, and to permit persons to whom the Software is
  26  * furnished to do so, subject to the following conditions:
  27  *
  28  * The above copyright notice and this permission notice shall be included in
  29  * all copies or substantial portions of the Software.
  30  *
  31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  32  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  33  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  34  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  35  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  36  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  37  * THE SOFTWARE.
  38  */
  39 #include "hw/hw.h"
  40 #include "hw/isa/isa.h"
  41 #include "hw/ppc/mac_dbdma.h"
  42 #include "qemu/main-loop.h"
  43
  44 /* debug DBDMA */
  45 //#define DEBUG_DBDMA
  46
  47 #ifdef DEBUG_DBDMA
  48 #define DBDMA_DPRINTF(fmt, ...)                                 \
  49     do { printf("DBDMA: " fmt , ## __VA_ARGS__); } while (0)
  50 #else
  51 #define DBDMA_DPRINTF(fmt, ...)
  52 #endif
  53
  54 /*
  55  */
  56
  57 /*
  58  * DBDMA control/status registers.  All little-endian.
  59  */
  60
  61 #define DBDMA_CONTROL         0x00
  62 #define DBDMA_STATUS          0x01
  63 #define DBDMA_CMDPTR_HI       0x02
  64 #define DBDMA_CMDPTR_LO       0x03
  65 #define DBDMA_INTR_SEL        0x04
  66 #define DBDMA_BRANCH_SEL      0x05
  67 #define DBDMA_WAIT_SEL        0x06
  68 #define DBDMA_XFER_MODE       0x07
  69 #define DBDMA_DATA2PTR_HI     0x08
  70 #define DBDMA_DATA2PTR_LO     0x09
  71 #define DBDMA_RES1            0x0A
  72 #define DBDMA_ADDRESS_HI      0x0B
  73 #define DBDMA_BRANCH_ADDR_HI  0x0C
  74 #define DBDMA_RES2            0x0D
  75 #define DBDMA_RES3            0x0E
  76 #define DBDMA_RES4            0x0F
  77
  78 #define DBDMA_REGS            16
  79 #define DBDMA_SIZE            (DBDMA_REGS * sizeof(uint32_t))
  80
  81 #define DBDMA_CHANNEL_SHIFT   7
  82 #define DBDMA_CHANNEL_SIZE    (1 << DBDMA_CHANNEL_SHIFT)
  83
  84 #define DBDMA_CHANNELS        (0x1000 >> DBDMA_CHANNEL_SHIFT)
  85
  86 /* Bits in control and status registers */
  87
  88 #define RUN     0x8000
  89 #define PAUSE   0x4000
  90 #define FLUSH   0x2000
  91 #define WAKE    0x1000
  92 #define DEAD    0x0800
  93 #define ACTIVE  0x0400
  94 #define BT      0x0100
  95 #define DEVSTAT 0x00ff
  96
  97 /*
  98  * DBDMA command structure.  These fields are all little-endian!
  99  */
 100
 101 typedef struct dbdma_cmd {
 102     uint16_t req_count;   /* requested byte transfer count */
 103     uint16_t command;     /* command word (has bit-fields) */
 104     uint32_t phy_addr;    /* physical data address */
 105     uint32_t cmd_dep;     /* command-dependent field */
 106     uint16_t res_count;   /* residual count after completion */
 107     uint16_t xfer_status; /* transfer status */
 108 } dbdma_cmd;
 109
 110 /* DBDMA command values in command field */
 111
 112 #define COMMAND_MASK    0xf000
 113 #define OUTPUT_MORE     0x0000  /* transfer memory data to stream */
 114 #define OUTPUT_LAST     0x1000  /* ditto followed by end marker */
 115 #define INPUT_MORE      0x2000  /* transfer stream data to memory */
 116 #define INPUT_LAST      0x3000  /* ditto, expect end marker */
 117 #define STORE_WORD      0x4000  /* write word (4 bytes) to device reg */
 118 #define LOAD_WORD       0x5000  /* read word (4 bytes) from device reg */
 119 #define DBDMA_NOP       0x6000  /* do nothing */
 120 #define DBDMA_STOP      0x7000  /* suspend processing */
 121
 122 /* Key values in command field */
 123
 124 #define KEY_MASK        0x0700
 125 #define KEY_STREAM0     0x0000  /* usual data stream */
 126 #define KEY_STREAM1     0x0100  /* control/status stream */
 127 #define KEY_STREAM2     0x0200  /* device-dependent stream */
 128 #define KEY_STREAM3     0x0300  /* device-dependent stream */
 129 #define KEY_STREAM4     0x0400  /* reserved */
 130 #define KEY_REGS        0x0500  /* device register space */
 131 #define KEY_SYSTEM      0x0600  /* system memory-mapped space */
 132 #define KEY_DEVICE      0x0700  /* device memory-mapped space */
 133
 134 /* Interrupt control values in command field */
 135
 136 #define INTR_MASK       0x0030
 137 #define INTR_NEVER      0x0000  /* don't interrupt */
 138 #define INTR_IFSET      0x0010  /* intr if condition bit is 1 */
 139 #define INTR_IFCLR      0x0020  /* intr if condition bit is 0 */
 140 #define INTR_ALWAYS     0x0030  /* always interrupt */
 141
 142 /* Branch control values in command field */
 143
 144 #define BR_MASK         0x000c
 145 #define BR_NEVER        0x0000  /* don't branch */
 146 #define BR_IFSET        0x0004  /* branch if condition bit is 1 */
 147 #define BR_IFCLR        0x0008  /* branch if condition bit is 0 */
 148 #define BR_ALWAYS       0x000c  /* always branch */
 149
 150 /* Wait control values in command field */
 151
 152 #define WAIT_MASK       0x0003
 153 #define WAIT_NEVER      0x0000  /* don't wait */
 154 #define WAIT_IFSET      0x0001  /* wait if condition bit is 1 */
 155 #define WAIT_IFCLR      0x0002  /* wait if condition bit is 0 */
 156 #define WAIT_ALWAYS     0x0003  /* always wait */
 157
 158 typedef struct DBDMA_channel {
 159     int channel;
 160     uint32_t regs[DBDMA_REGS];
 161     qemu_irq irq;
 162     DBDMA_io io;
 163     DBDMA_rw rw;
 164     DBDMA_flush flush;
 165     dbdma_cmd current;
 166     int processing;
 167 } DBDMA_channel;
 168
 169 typedef struct {
 170     MemoryRegion mem;
 171     DBDMA_channel channels[DBDMA_CHANNELS];
 172 } DBDMAState;
 173
 174 #ifdef DEBUG_DBDMA
 175 static void dump_dbdma_cmd(dbdma_cmd *cmd)
 176 {
 177     printf("dbdma_cmd %p\n", cmd);
 178     printf("    req_count 0x%04x\n", le16_to_cpu(cmd->req_count));
 179     printf("    command 0x%04x\n", le16_to_cpu(cmd->command));
 180     printf("    phy_addr 0x%08x\n", le32_to_cpu(cmd->phy_addr));
 181     printf("    cmd_dep 0x%08x\n", le32_to_cpu(cmd->cmd_dep));
 182     printf("    res_count 0x%04x\n", le16_to_cpu(cmd->res_count));
 183     printf("    xfer_status 0x%04x\n", le16_to_cpu(cmd->xfer_status));
 184 }
 185 #else
 186 static void dump_dbdma_cmd(dbdma_cmd *cmd)
 187 {
 188 }
 189 #endif
 190 static void dbdma_cmdptr_load(DBDMA_channel *ch)
 191 {
 192     DBDMA_DPRINTF("dbdma_cmdptr_load 0x%08x\n",
 193                   ch->regs[DBDMA_CMDPTR_LO]);
 194     cpu_physical_memory_read(ch->regs[DBDMA_CMDPTR_LO],
 195                              &ch->current, sizeof(dbdma_cmd));
 196 }
 197
 198 static void dbdma_cmdptr_save(DBDMA_channel *ch)
 199 {
 200     DBDMA_DPRINTF("dbdma_cmdptr_save 0x%08x\n",
 201                   ch->regs[DBDMA_CMDPTR_LO]);
 202     DBDMA_DPRINTF("xfer_status 0x%08x res_count 0x%04x\n",
 203                   le16_to_cpu(ch->current.xfer_status),
 204                   le16_to_cpu(ch->current.res_count));
 205     cpu_physical_memory_write(ch->regs[DBDMA_CMDPTR_LO],
 206                               &ch->current, sizeof(dbdma_cmd));
 207 }
 208
 209 static void kill_channel(DBDMA_channel *ch)
 210 {
 211     DBDMA_DPRINTF("kill_channel\n");
 212
 213     ch->regs[DBDMA_STATUS] |= DEAD;
 214     ch->regs[DBDMA_STATUS] &= ~ACTIVE;
 215
 216     qemu_irq_raise(ch->irq);
 217 }
 218
 219 static void conditional_interrupt(DBDMA_channel *ch)
 220 {
 221     dbdma_cmd *current = &ch->current;
 222     uint16_t intr;
 223     uint16_t sel_mask, sel_value;
 224     uint32_t status;
 225     int cond;
 226
 227     DBDMA_DPRINTF("conditional_interrupt\n");
 228
 229     intr = le16_to_cpu(current->command) & INTR_MASK;
 230
 231     switch(intr) {
 232     case INTR_NEVER:  /* don't interrupt */
 233         return;
 234     case INTR_ALWAYS: /* always interrupt */
 235         qemu_irq_raise(ch->irq);
 236         return;
 237     }
 238
 239     status = ch->regs[DBDMA_STATUS] & DEVSTAT;
 240
 241     sel_mask = (ch->regs[DBDMA_INTR_SEL] >> 16) & 0x0f;
 242     sel_value = ch->regs[DBDMA_INTR_SEL] & 0x0f;
 243
 244     cond = (status & sel_mask) == (sel_value & sel_mask);
 245
 246     switch(intr) {
 247     case INTR_IFSET:  /* intr if condition bit is 1 */
 248         if (cond)
 249             qemu_irq_raise(ch->irq);
 250         return;
 251     case INTR_IFCLR:  /* intr if condition bit is 0 */
 252         if (!cond)
 253             qemu_irq_raise(ch->irq);
 254         return;
 255     }
 256 }
 257
 258 static int conditional_wait(DBDMA_channel *ch)
 259 {
 260     dbdma_cmd *current = &ch->current;
 261     uint16_t wait;
 262     uint16_t sel_mask, sel_value;
 263     uint32_t status;
 264     int cond;
 265
 266     DBDMA_DPRINTF("conditional_wait\n");
 267
 268     wait = le16_to_cpu(current->command) & WAIT_MASK;
 269
 270     switch(wait) {
 271     case WAIT_NEVER:  /* don't wait */
 272         return 0;
 273     case WAIT_ALWAYS: /* always wait */
 274         return 1;
 275     }
 276
 277     status = ch->regs[DBDMA_STATUS] & DEVSTAT;
 278
 279     sel_mask = (ch->regs[DBDMA_WAIT_SEL] >> 16) & 0x0f;
 280     sel_value = ch->regs[DBDMA_WAIT_SEL] & 0x0f;
 281
 282     cond = (status & sel_mask) == (sel_value & sel_mask);
 283
 284     switch(wait) {
 285     case WAIT_IFSET:  /* wait if condition bit is 1 */
 286         if (cond)
 287             return 1;
 288         return 0;
 289     case WAIT_IFCLR:  /* wait if condition bit is 0 */
 290         if (!cond)
 291             return 1;
 292         return 0;
 293     }
 294     return 0;
 295 }
 296
 297 static void next(DBDMA_channel *ch)
 298 {
 299     uint32_t cp;
 300
 301     ch->regs[DBDMA_STATUS] &= ~BT;
 302
 303     cp = ch->regs[DBDMA_CMDPTR_LO];
 304     ch->regs[DBDMA_CMDPTR_LO] = cp + sizeof(dbdma_cmd);
 305     dbdma_cmdptr_load(ch);
 306 }
 307
 308 static void branch(DBDMA_channel *ch)
 309 {
 310     dbdma_cmd *current = &ch->current;
 311
 312     ch->regs[DBDMA_CMDPTR_LO] = current->cmd_dep;
 313     ch->regs[DBDMA_STATUS] |= BT;
 314     dbdma_cmdptr_load(ch);
 315 }
 316
 317 static void conditional_branch(DBDMA_channel *ch)
 318 {
 319     dbdma_cmd *current = &ch->current;
 320     uint16_t br;
 321     uint16_t sel_mask, sel_value;
 322     uint32_t status;
 323     int cond;
 324
 325     DBDMA_DPRINTF("conditional_branch\n");
 326
 327     /* check if we must branch */
 328
 329     br = le16_to_cpu(current->command) & BR_MASK;
 330
 331     switch(br) {
 332     case BR_NEVER:  /* don't branch */
 333         next(ch);
 334         return;
 335     case BR_ALWAYS: /* always branch */
 336         branch(ch);
 337         return;
 338     }
 339
 340     status = ch->regs[DBDMA_STATUS] & DEVSTAT;
 341
 342     sel_mask = (ch->regs[DBDMA_BRANCH_SEL] >> 16) & 0x0f;
 343     sel_value = ch->regs[DBDMA_BRANCH_SEL] & 0x0f;
 344
 345     cond = (status & sel_mask) == (sel_value & sel_mask);
 346
 347     switch(br) {
 348     case BR_IFSET:  /* branch if condition bit is 1 */
 349         if (cond)
 350             branch(ch);
 351         else
 352             next(ch);
 353         return;
 354     case BR_IFCLR:  /* branch if condition bit is 0 */
 355         if (!cond)
 356             branch(ch);
 357         else
 358             next(ch);
 359         return;
 360     }
 361 }
 362
 363 static QEMUBH *dbdma_bh;
 364 static void channel_run(DBDMA_channel *ch);
 365
 366 static void dbdma_end(DBDMA_io *io)
 367 {
 368     DBDMA_channel *ch = io->channel;
 369     dbdma_cmd *current = &ch->current;
 370
 371     if (conditional_wait(ch))
 372         goto wait;
 373
 374     current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
 375     current->res_count = cpu_to_le16(io->len);
 376     dbdma_cmdptr_save(ch);
 377     if (io->is_last)
 378         ch->regs[DBDMA_STATUS] &= ~FLUSH;
 379
 380     conditional_interrupt(ch);
 381     conditional_branch(ch);
 382
 383 wait:
 384     ch->processing = 0;
 385     if ((ch->regs[DBDMA_STATUS] & RUN) &&
 386         (ch->regs[DBDMA_STATUS] & ACTIVE))
 387         channel_run(ch);
 388 }
 389
 390 static void start_output(DBDMA_channel *ch, int key, uint32_t addr,
 391                         uint16_t req_count, int is_last)
 392 {
 393     DBDMA_DPRINTF("start_output\n");
 394
 395     /* KEY_REGS, KEY_DEVICE and KEY_STREAM
 396      * are not implemented in the mac-io chip
 397      */
 398
 399     DBDMA_DPRINTF("addr 0x%x key 0x%x\n", addr, key);
 400     if (!addr || key > KEY_STREAM3) {
 401         kill_channel(ch);
 402         return;
 403     }
 404
 405     ch->io.addr = addr;
 406     ch->io.len = req_count;
 407     ch->io.is_last = is_last;
 408     ch->io.dma_end = dbdma_end;
 409     ch->io.is_dma_out = 1;
 410     ch->processing = 1;
 411     if (ch->rw) {
 412         ch->rw(&ch->io);
 413     }
 414 }
 415
 416 static void start_input(DBDMA_channel *ch, int key, uint32_t addr,
 417                        uint16_t req_count, int is_last)
 418 {
 419     DBDMA_DPRINTF("start_input\n");
 420
 421     /* KEY_REGS, KEY_DEVICE and KEY_STREAM
 422      * are not implemented in the mac-io chip
 423      */
 424
 425     if (!addr || key > KEY_STREAM3) {
 426         kill_channel(ch);
 427         return;
 428     }
 429
 430     ch->io.addr = addr;
 431     ch->io.len = req_count;
 432     ch->io.is_last = is_last;
 433     ch->io.dma_end = dbdma_end;
 434     ch->io.is_dma_out = 0;
 435     ch->processing = 1;
 436     if (ch->rw) {
 437         ch->rw(&ch->io);
 438     }
 439 }
 440
 441 static void load_word(DBDMA_channel *ch, int key, uint32_t addr,
 442                      uint16_t len)
 443 {
 444     dbdma_cmd *current = &ch->current;
 445     uint32_t val;
 446
 447     DBDMA_DPRINTF("load_word\n");
 448
 449     /* only implements KEY_SYSTEM */
 450
 451     if (key != KEY_SYSTEM) {
 452         printf("DBDMA: LOAD_WORD, unimplemented key %x\n", key);
 453         kill_channel(ch);
 454         return;
 455     }
 456
 457     cpu_physical_memory_read(addr, &val, len);
 458
 459     if (len == 2)
 460         val = (val << 16) | (current->cmd_dep & 0x0000ffff);
 461     else if (len == 1)
 462         val = (val << 24) | (current->cmd_dep & 0x00ffffff);
 463
 464     current->cmd_dep = val;
 465
 466     if (conditional_wait(ch))
 467         goto wait;
 468
 469     current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
 470     dbdma_cmdptr_save(ch);
 471     ch->regs[DBDMA_STATUS] &= ~FLUSH;
 472
 473     conditional_interrupt(ch);
 474     next(ch);
 475
 476 wait:
 477     qemu_bh_schedule(dbdma_bh);
 478 }
 479
 480 static void store_word(DBDMA_channel *ch, int key, uint32_t addr,
 481                       uint16_t len)
 482 {
 483     dbdma_cmd *current = &ch->current;
 484     uint32_t val;
 485
 486     DBDMA_DPRINTF("store_word\n");
 487
 488     /* only implements KEY_SYSTEM */
 489
 490     if (key != KEY_SYSTEM) {
 491         printf("DBDMA: STORE_WORD, unimplemented key %x\n", key);
 492         kill_channel(ch);
 493         return;
 494     }
 495
 496     val = current->cmd_dep;
 497     if (len == 2)
 498         val >>= 16;
 499     else if (len == 1)
 500         val >>= 24;
 501
 502     cpu_physical_memory_write(addr, &val, len);
 503
 504     if (conditional_wait(ch))
 505         goto wait;
 506
 507     current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
 508     dbdma_cmdptr_save(ch);
 509     ch->regs[DBDMA_STATUS] &= ~FLUSH;
 510
 511     conditional_interrupt(ch);
 512     next(ch);
 513
 514 wait:
 515     qemu_bh_schedule(dbdma_bh);
 516 }
 517
 518 static void nop(DBDMA_channel *ch)
 519 {
 520     dbdma_cmd *current = &ch->current;
 521
 522     if (conditional_wait(ch))
 523         goto wait;
 524
 525     current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
 526     dbdma_cmdptr_save(ch);
 527
 528     conditional_interrupt(ch);
 529     conditional_branch(ch);
 530
 531 wait:
 532     qemu_bh_schedule(dbdma_bh);
 533 }
 534
 535 static void stop(DBDMA_channel *ch)
 536 {
 537     ch->regs[DBDMA_STATUS] &= ~(ACTIVE|DEAD|FLUSH);
 538
 539     /* the stop command does not increment command pointer */
 540 }
 541
 542 static void channel_run(DBDMA_channel *ch)
 543 {
 544     dbdma_cmd *current = &ch->current;
 545     uint16_t cmd, key;
 546     uint16_t req_count;
 547     uint32_t phy_addr;
 548
 549     DBDMA_DPRINTF("channel_run\n");
 550     dump_dbdma_cmd(current);
 551
 552     /* clear WAKE flag at command fetch */
 553
 554     ch->regs[DBDMA_STATUS] &= ~WAKE;
 555
 556     cmd = le16_to_cpu(current->command) & COMMAND_MASK;
 557
 558     switch (cmd) {
 559     case DBDMA_NOP:
 560         nop(ch);
 561         return;
 562
 563     case DBDMA_STOP:
 564         stop(ch);
 565         return;
 566     }
 567
 568     key = le16_to_cpu(current->command) & 0x0700;
 569     req_count = le16_to_cpu(current->req_count);
 570     phy_addr = le32_to_cpu(current->phy_addr);
 571
 572     if (key == KEY_STREAM4) {
 573         printf("command %x, invalid key 4\n", cmd);
 574         kill_channel(ch);
 575         return;
 576     }
 577
 578     switch (cmd) {
 579     case OUTPUT_MORE:
 580         start_output(ch, key, phy_addr, req_count, 0);
 581         return;
 582
 583     case OUTPUT_LAST:
 584         start_output(ch, key, phy_addr, req_count, 1);
 585         return;
 586
 587     case INPUT_MORE:
 588         start_input(ch, key, phy_addr, req_count, 0);
 589         return;
 590
 591     case INPUT_LAST:
 592         start_input(ch, key, phy_addr, req_count, 1);
 593         return;
 594     }
 595
 596     if (key < KEY_REGS) {
 597         printf("command %x, invalid key %x\n", cmd, key);
 598         key = KEY_SYSTEM;
 599     }
 600
 601     /* for LOAD_WORD and STORE_WORD, req_count is on 3 bits
 602      * and BRANCH is invalid
 603      */
 604
 605     req_count = req_count & 0x0007;
 606     if (req_count & 0x4) {
 607         req_count = 4;
 608         phy_addr &= ~3;
 609     } else if (req_count & 0x2) {
 610         req_count = 2;
 611         phy_addr &= ~1;
 612     } else
 613         req_count = 1;
 614
 615     switch (cmd) {
 616     case LOAD_WORD:
 617         load_word(ch, key, phy_addr, req_count);
 618         return;
 619
 620     case STORE_WORD:
 621         store_word(ch, key, phy_addr, req_count);
 622         return;
 623     }
 624 }
 625
 626 static void DBDMA_run(DBDMAState *s)
 627 {
 628     int channel;
 629
 630     for (channel = 0; channel < DBDMA_CHANNELS; channel++) {
 631         DBDMA_channel *ch = &s->channels[channel];
 632         uint32_t status = ch->regs[DBDMA_STATUS];
 633         if (!ch->processing && (status & RUN) && (status & ACTIVE)) {
 634             channel_run(ch);
 635         }
 636     }
 637 }
 638
 639 static void DBDMA_run_bh(void *opaque)
 640 {
 641     DBDMAState *s = opaque;
 642
 643     DBDMA_DPRINTF("DBDMA_run_bh\n");
 644
 645     DBDMA_run(s);
 646 }
 647
 648 void DBDMA_register_channel(void *dbdma, int nchan, qemu_irq irq,
 649                             DBDMA_rw rw, DBDMA_flush flush,
 650                             void *opaque)
 651 {
 652     DBDMAState *s = dbdma;
 653     DBDMA_channel *ch = &s->channels[nchan];
 654
 655     DBDMA_DPRINTF("DBDMA_register_channel 0x%x\n", nchan);
 656
 657     ch->irq = irq;
 658     ch->channel = nchan;
 659     ch->rw = rw;
 660     ch->flush = flush;
 661     ch->io.opaque = opaque;
 662     ch->io.channel = ch;
 663 }
 664
 665 static void
 666 dbdma_control_write(DBDMA_channel *ch)
 667 {
 668     uint16_t mask, value;
 669     uint32_t status;
 670
 671     mask = (ch->regs[DBDMA_CONTROL] >> 16) & 0xffff;
 672     value = ch->regs[DBDMA_CONTROL] & 0xffff;
 673
 674     value &= (RUN | PAUSE | FLUSH | WAKE | DEVSTAT);
 675
 676     status = ch->regs[DBDMA_STATUS];
 677
 678     status = (value & mask) | (status & ~mask);
 679
 680     if (status & WAKE)
 681         status |= ACTIVE;
 682     if (status & RUN) {
 683         status |= ACTIVE;
 684         status &= ~DEAD;
 685     }
 686     if (status & PAUSE)
 687         status &= ~ACTIVE;
 688     if ((ch->regs[DBDMA_STATUS] & RUN) && !(status & RUN)) {
 689         /* RUN is cleared */
 690         status &= ~(ACTIVE|DEAD);
 691         if ((status & FLUSH) && ch->flush) {
 692             ch->flush(&ch->io);
 693             status &= ~FLUSH;
 694         }
 695     }
 696
 697     DBDMA_DPRINTF("    status 0x%08x\n", status);
 698
 699     ch->regs[DBDMA_STATUS] = status;
 700
 701     if (status & ACTIVE)
 702         qemu_bh_schedule(dbdma_bh);
 703     if ((status & FLUSH) && ch->flush)
 704         ch->flush(&ch->io);
 705 }
 706
 707 static void dbdma_write(void *opaque, hwaddr addr,
 708                         uint64_t value, unsigned size)
 709 {
 710     int channel = addr >> DBDMA_CHANNEL_SHIFT;
 711     DBDMAState *s = opaque;
 712     DBDMA_channel *ch = &s->channels[channel];
 713     int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
 714
 715     DBDMA_DPRINTF("writel 0x" TARGET_FMT_plx " <= 0x%08x\n", addr, value);
 716     DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
 717                   (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
 718
 719     /* cmdptr cannot be modified if channel is RUN or ACTIVE */
 720
 721     if (reg == DBDMA_CMDPTR_LO &&
 722         (ch->regs[DBDMA_STATUS] & (RUN | ACTIVE)))
 723         return;
 724
 725     ch->regs[reg] = value;
 726
 727     switch(reg) {
 728     case DBDMA_CONTROL:
 729         dbdma_control_write(ch);
 730         break;
 731     case DBDMA_CMDPTR_LO:
 732         /* 16-byte aligned */
 733         ch->regs[DBDMA_CMDPTR_LO] &= ~0xf;
 734         dbdma_cmdptr_load(ch);
 735         break;
 736     case DBDMA_STATUS:
 737     case DBDMA_INTR_SEL:
 738     case DBDMA_BRANCH_SEL:
 739     case DBDMA_WAIT_SEL:
 740         /* nothing to do */
 741         break;
 742     case DBDMA_XFER_MODE:
 743     case DBDMA_CMDPTR_HI:
 744     case DBDMA_DATA2PTR_HI:
 745     case DBDMA_DATA2PTR_LO:
 746     case DBDMA_ADDRESS_HI:
 747     case DBDMA_BRANCH_ADDR_HI:
 748     case DBDMA_RES1:
 749     case DBDMA_RES2:
 750     case DBDMA_RES3:
 751     case DBDMA_RES4:
 752         /* unused */
 753         break;
 754     }
 755 }
 756
 757 static uint64_t dbdma_read(void *opaque, hwaddr addr,
 758                            unsigned size)
 759 {
 760     uint32_t value;
 761     int channel = addr >> DBDMA_CHANNEL_SHIFT;
 762     DBDMAState *s = opaque;
 763     DBDMA_channel *ch = &s->channels[channel];
 764     int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
 765
 766     value = ch->regs[reg];
 767
 768     DBDMA_DPRINTF("readl 0x" TARGET_FMT_plx " => 0x%08x\n", addr, value);
 769     DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
 770                   (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
 771
 772     switch(reg) {
 773     case DBDMA_CONTROL:
 774         value = 0;
 775         break;
 776     case DBDMA_STATUS:
 777     case DBDMA_CMDPTR_LO:
 778     case DBDMA_INTR_SEL:
 779     case DBDMA_BRANCH_SEL:
 780     case DBDMA_WAIT_SEL:
 781         /* nothing to do */
 782         break;
 783     case DBDMA_XFER_MODE:
 784     case DBDMA_CMDPTR_HI:
 785     case DBDMA_DATA2PTR_HI:
 786     case DBDMA_DATA2PTR_LO:
 787     case DBDMA_ADDRESS_HI:
 788     case DBDMA_BRANCH_ADDR_HI:
 789         /* unused */
 790         value = 0;
 791         break;
 792     case DBDMA_RES1:
 793     case DBDMA_RES2:
 794     case DBDMA_RES3:
 795     case DBDMA_RES4:
 796         /* reserved */
 797         break;
 798     }
 799
 800     return value;
 801 }
 802
 803 static const MemoryRegionOps dbdma_ops = {
 804     .read = dbdma_read,
 805     .write = dbdma_write,
 806     .endianness = DEVICE_LITTLE_ENDIAN,
 807     .valid = {
 808         .min_access_size = 4,
 809         .max_access_size = 4,
 810     },
 811 };
 812
 813 static const VMStateDescription vmstate_dbdma_channel = {
 814     .name = "dbdma_channel",
 815     .version_id = 0,
 816     .minimum_version_id = 0,
 817     .minimum_version_id_old = 0,
 818     .fields      = (VMStateField[]) {
 819         VMSTATE_UINT32_ARRAY(regs, struct DBDMA_channel, DBDMA_REGS),
 820         VMSTATE_END_OF_LIST()
 821     }
 822 };
 823
 824 static const VMStateDescription vmstate_dbdma = {
 825     .name = "dbdma",
 826     .version_id = 2,
 827     .minimum_version_id = 2,
 828     .minimum_version_id_old = 2,
 829     .fields      = (VMStateField[]) {
 830         VMSTATE_STRUCT_ARRAY(channels, DBDMAState, DBDMA_CHANNELS, 1,
 831                              vmstate_dbdma_channel, DBDMA_channel),
 832         VMSTATE_END_OF_LIST()
 833     }
 834 };
 835
 836 static void dbdma_reset(void *opaque)
 837 {
 838     DBDMAState *s = opaque;
 839     int i;
 840
 841     for (i = 0; i < DBDMA_CHANNELS; i++)
 842         memset(s->channels[i].regs, 0, DBDMA_SIZE);
 843 }
 844
 845 void* DBDMA_init (MemoryRegion **dbdma_mem)
 846 {
 847     DBDMAState *s;
 848
 849     s = g_malloc0(sizeof(DBDMAState));
 850
 851     memory_region_init_io(&s->mem, &dbdma_ops, s, "dbdma", 0x1000);
 852     *dbdma_mem = &s->mem;
 853     vmstate_register(NULL, -1, &vmstate_dbdma, s);
 854     qemu_register_reset(dbdma_reset, s);
 855
 856     dbdma_bh = qemu_bh_new(DBDMA_run_bh, s);
 857
 858     return s;
 859 }