hw/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.h"
  40 #include "isa.h"
  41 #include "mac_dbdma.h"
  42
  43 /* debug DBDMA */
  44 //#define DEBUG_DBDMA
  45
  46 #ifdef DEBUG_DBDMA
  47 #define DBDMA_DPRINTF(fmt, args...) \
  48 do { printf("DBDMA: " fmt , ##args); } while (0)
  49 #else
  50 #define DBDMA_DPRINTF(fmt, args...)
  51 #endif
  52
  53 /*
  54  */
  55
  56 /*
  57  * DBDMA control/status registers.  All little-endian.
  58  */
  59
  60 #define DBDMA_CONTROL         0x00
  61 #define DBDMA_STATUS          0x01
  62 #define DBDMA_CMDPTR_HI       0x02
  63 #define DBDMA_CMDPTR_LO       0x03
  64 #define DBDMA_INTR_SEL        0x04
  65 #define DBDMA_BRANCH_SEL      0x05
  66 #define DBDMA_WAIT_SEL        0x06
  67 #define DBDMA_XFER_MODE       0x07
  68 #define DBDMA_DATA2PTR_HI     0x08
  69 #define DBDMA_DATA2PTR_LO     0x09
  70 #define DBDMA_RES1            0x0A
  71 #define DBDMA_ADDRESS_HI      0x0B
  72 #define DBDMA_BRANCH_ADDR_HI  0x0C
  73 #define DBDMA_RES2            0x0D
  74 #define DBDMA_RES3            0x0E
  75 #define DBDMA_RES4            0x0F
  76
  77 #define DBDMA_REGS            16
  78 #define DBDMA_SIZE            (DBDMA_REGS * sizeof(uint32_t))
  79
  80 #define DBDMA_CHANNEL_SHIFT   7
  81 #define DBDMA_CHANNEL_SIZE    (1 << DBDMA_CHANNEL_SHIFT)
  82
  83 #define DBDMA_CHANNELS        (0x1000 >> DBDMA_CHANNEL_SHIFT)
  84
  85 /* Bits in control and status registers */
  86
  87 #define RUN     0x8000
  88 #define PAUSE   0x4000
  89 #define FLUSH   0x2000
  90 #define WAKE    0x1000
  91 #define DEAD    0x0800
  92 #define ACTIVE  0x0400
  93 #define BT      0x0100
  94 #define DEVSTAT 0x00ff
  95
  96 /*
  97  * DBDMA command structure.  These fields are all little-endian!
  98  */
  99
 100 typedef struct dbdma_cmd {
 101     uint16_t req_count;   /* requested byte transfer count */
 102     uint16_t command;     /* command word (has bit-fields) */
 103     uint32_t phy_addr;    /* physical data address */
 104     uint32_t cmd_dep;     /* command-dependent field */
 105     uint16_t res_count;   /* residual count after completion */
 106     uint16_t xfer_status; /* transfer status */
 107 } dbdma_cmd;
 108
 109 /* DBDMA command values in command field */
 110
 111 #define COMMAND_MASK    0xf000
 112 #define OUTPUT_MORE     0x0000  /* transfer memory data to stream */
 113 #define OUTPUT_LAST     0x1000  /* ditto followed by end marker */
 114 #define INPUT_MORE      0x2000  /* transfer stream data to memory */
 115 #define INPUT_LAST      0x3000  /* ditto, expect end marker */
 116 #define STORE_WORD      0x4000  /* write word (4 bytes) to device reg */
 117 #define LOAD_WORD       0x5000  /* read word (4 bytes) from device reg */
 118 #define DBDMA_NOP       0x6000  /* do nothing */
 119 #define DBDMA_STOP      0x7000  /* suspend processing */
 120
 121 /* Key values in command field */
 122
 123 #define KEY_MASK        0x0700
 124 #define KEY_STREAM0     0x0000  /* usual data stream */
 125 #define KEY_STREAM1     0x0100  /* control/status stream */
 126 #define KEY_STREAM2     0x0200  /* device-dependent stream */
 127 #define KEY_STREAM3     0x0300  /* device-dependent stream */
 128 #define KEY_STREAM4     0x0400  /* reserved */
 129 #define KEY_REGS        0x0500  /* device register space */
 130 #define KEY_SYSTEM      0x0600  /* system memory-mapped space */
 131 #define KEY_DEVICE      0x0700  /* device memory-mapped space */
 132
 133 /* Interrupt control values in command field */
 134
 135 #define INTR_MASK       0x0030
 136 #define INTR_NEVER      0x0000  /* don't interrupt */
 137 #define INTR_IFSET      0x0010  /* intr if condition bit is 1 */
 138 #define INTR_IFCLR      0x0020  /* intr if condition bit is 0 */
 139 #define INTR_ALWAYS     0x0030  /* always interrupt */
 140
 141 /* Branch control values in command field */
 142
 143 #define BR_MASK         0x000c
 144 #define BR_NEVER        0x0000  /* don't branch */
 145 #define BR_IFSET        0x0004  /* branch if condition bit is 1 */
 146 #define BR_IFCLR        0x0008  /* branch if condition bit is 0 */
 147 #define BR_ALWAYS       0x000c  /* always branch */
 148
 149 /* Wait control values in command field */
 150
 151 #define WAIT_MASK       0x0003
 152 #define WAIT_NEVER      0x0000  /* don't wait */
 153 #define WAIT_IFSET      0x0001  /* wait if condition bit is 1 */
 154 #define WAIT_IFCLR      0x0002  /* wait if condition bit is 0 */
 155 #define WAIT_ALWAYS     0x0003  /* always wait */
 156
 157 typedef struct DBDMA_channel {
 158     int channel;
 159     uint32_t regs[DBDMA_REGS];
 160     qemu_irq irq;
 161     DBDMA_io io;
 162     DBDMA_rw rw;
 163     DBDMA_flush flush;
 164     dbdma_cmd current;
 165     int processing;
 166 } DBDMA_channel;
 167
 168 #ifdef DEBUG_DBDMA
 169 static void dump_dbdma_cmd(dbdma_cmd *cmd)
 170 {
 171     printf("dbdma_cmd %p\n", cmd);
 172     printf("    req_count 0x%04x\n", le16_to_cpu(cmd->req_count));
 173     printf("    command 0x%04x\n", le16_to_cpu(cmd->command));
 174     printf("    phy_addr 0x%08x\n", le32_to_cpu(cmd->phy_addr));
 175     printf("    cmd_dep 0x%08x\n", le32_to_cpu(cmd->cmd_dep));
 176     printf("    res_count 0x%04x\n", le16_to_cpu(cmd->res_count));
 177     printf("    xfer_status 0x%04x\n", le16_to_cpu(cmd->xfer_status));
 178 }
 179 #else
 180 static void dump_dbdma_cmd(dbdma_cmd *cmd)
 181 {
 182 }
 183 #endif
 184 static void dbdma_cmdptr_load(DBDMA_channel *ch)
 185 {
 186     DBDMA_DPRINTF("dbdma_cmdptr_load 0x%08x\n",
 187                   be32_to_cpu(ch->regs[DBDMA_CMDPTR_LO]));
 188     cpu_physical_memory_read(be32_to_cpu(ch->regs[DBDMA_CMDPTR_LO]),
 189                              (uint8_t*)&ch->current, sizeof(dbdma_cmd));
 190 }
 191
 192 static void dbdma_cmdptr_save(DBDMA_channel *ch)
 193 {
 194     DBDMA_DPRINTF("dbdma_cmdptr_save 0x%08x\n",
 195                   be32_to_cpu(ch->regs[DBDMA_CMDPTR_LO]));
 196     DBDMA_DPRINTF("xfer_status 0x%08x res_count 0x%04x\n",
 197                   le16_to_cpu(ch->current.xfer_status),
 198                   le16_to_cpu(ch->current.res_count));
 199     cpu_physical_memory_write(be32_to_cpu(ch->regs[DBDMA_CMDPTR_LO]),
 200                               (uint8_t*)&ch->current, sizeof(dbdma_cmd));
 201 }
 202
 203 static void kill_channel(DBDMA_channel *ch)
 204 {
 205     DBDMA_DPRINTF("kill_channel\n");
 206
 207     ch->regs[DBDMA_STATUS] |= cpu_to_be32(DEAD);
 208     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~ACTIVE);
 209
 210     qemu_irq_raise(ch->irq);
 211 }
 212
 213 static void conditional_interrupt(DBDMA_channel *ch)
 214 {
 215     dbdma_cmd *current = &ch->current;
 216     uint16_t intr;
 217     uint16_t sel_mask, sel_value;
 218     uint32_t status;
 219     int cond;
 220
 221     DBDMA_DPRINTF("conditional_interrupt\n");
 222
 223     intr = le16_to_cpu(current->command) & INTR_MASK;
 224
 225     switch(intr) {
 226     case INTR_NEVER:  /* don't interrupt */
 227         return;
 228     case INTR_ALWAYS: /* always interrupt */
 229         qemu_irq_raise(ch->irq);
 230         return;
 231     }
 232
 233     status = be32_to_cpu(ch->regs[DBDMA_STATUS]) & DEVSTAT;
 234
 235     sel_mask = (be32_to_cpu(ch->regs[DBDMA_INTR_SEL]) >> 16) & 0x0f;
 236     sel_value = be32_to_cpu(ch->regs[DBDMA_INTR_SEL]) & 0x0f;
 237
 238     cond = (status & sel_mask) == (sel_value & sel_mask);
 239
 240     switch(intr) {
 241     case INTR_IFSET:  /* intr if condition bit is 1 */
 242         if (cond)
 243             qemu_irq_raise(ch->irq);
 244         return;
 245     case INTR_IFCLR:  /* intr if condition bit is 0 */
 246         if (!cond)
 247             qemu_irq_raise(ch->irq);
 248         return;
 249     }
 250 }
 251
 252 static int conditional_wait(DBDMA_channel *ch)
 253 {
 254     dbdma_cmd *current = &ch->current;
 255     uint16_t wait;
 256     uint16_t sel_mask, sel_value;
 257     uint32_t status;
 258     int cond;
 259
 260     DBDMA_DPRINTF("conditional_wait\n");
 261
 262     wait = le16_to_cpu(current->command) & WAIT_MASK;
 263
 264     switch(wait) {
 265     case WAIT_NEVER:  /* don't wait */
 266         return 0;
 267     case WAIT_ALWAYS: /* always wait */
 268         return 1;
 269     }
 270
 271     status = be32_to_cpu(ch->regs[DBDMA_STATUS]) & DEVSTAT;
 272
 273     sel_mask = (be32_to_cpu(ch->regs[DBDMA_WAIT_SEL]) >> 16) & 0x0f;
 274     sel_value = be32_to_cpu(ch->regs[DBDMA_WAIT_SEL]) & 0x0f;
 275
 276     cond = (status & sel_mask) == (sel_value & sel_mask);
 277
 278     switch(wait) {
 279     case WAIT_IFSET:  /* wait if condition bit is 1 */
 280         if (cond)
 281             return 1;
 282         return 0;
 283     case WAIT_IFCLR:  /* wait if condition bit is 0 */
 284         if (!cond)
 285             return 1;
 286         return 0;
 287     }
 288     return 0;
 289 }
 290
 291 static void next(DBDMA_channel *ch)
 292 {
 293     uint32_t cp;
 294
 295     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~BT);
 296
 297     cp = be32_to_cpu(ch->regs[DBDMA_CMDPTR_LO]);
 298     ch->regs[DBDMA_CMDPTR_LO] = cpu_to_be32(cp + sizeof(dbdma_cmd));
 299     dbdma_cmdptr_load(ch);
 300 }
 301
 302 static void branch(DBDMA_channel *ch)
 303 {
 304     dbdma_cmd *current = &ch->current;
 305
 306     ch->regs[DBDMA_CMDPTR_LO] = current->cmd_dep;
 307     ch->regs[DBDMA_STATUS] |= cpu_to_be32(BT);
 308     dbdma_cmdptr_load(ch);
 309 }
 310
 311 static void conditional_branch(DBDMA_channel *ch)
 312 {
 313     dbdma_cmd *current = &ch->current;
 314     uint16_t br;
 315     uint16_t sel_mask, sel_value;
 316     uint32_t status;
 317     int cond;
 318
 319     DBDMA_DPRINTF("conditional_branch\n");
 320
 321     /* check if we must branch */
 322
 323     br = le16_to_cpu(current->command) & BR_MASK;
 324
 325     switch(br) {
 326     case BR_NEVER:  /* don't branch */
 327         next(ch);
 328         return;
 329     case BR_ALWAYS: /* always branch */
 330         branch(ch);
 331         return;
 332     }
 333
 334     status = be32_to_cpu(ch->regs[DBDMA_STATUS]) & DEVSTAT;
 335
 336     sel_mask = (be32_to_cpu(ch->regs[DBDMA_BRANCH_SEL]) >> 16) & 0x0f;
 337     sel_value = be32_to_cpu(ch->regs[DBDMA_BRANCH_SEL]) & 0x0f;
 338
 339     cond = (status & sel_mask) == (sel_value & sel_mask);
 340
 341     switch(br) {
 342     case BR_IFSET:  /* branch if condition bit is 1 */
 343         if (cond)
 344             branch(ch);
 345         else
 346             next(ch);
 347         return;
 348     case BR_IFCLR:  /* branch if condition bit is 0 */
 349         if (!cond)
 350             branch(ch);
 351         else
 352             next(ch);
 353         return;
 354     }
 355 }
 356
 357 static QEMUBH *dbdma_bh;
 358 static void channel_run(DBDMA_channel *ch);
 359
 360 static void dbdma_end(DBDMA_io *io)
 361 {
 362     DBDMA_channel *ch = io->channel;
 363     dbdma_cmd *current = &ch->current;
 364
 365     if (conditional_wait(ch))
 366         goto wait;
 367
 368     current->xfer_status = cpu_to_le16(be32_to_cpu(ch->regs[DBDMA_STATUS]));
 369     current->res_count = cpu_to_le16(be32_to_cpu(io->len));
 370     dbdma_cmdptr_save(ch);
 371     if (io->is_last)
 372         ch->regs[DBDMA_STATUS] &= cpu_to_be32(~FLUSH);
 373
 374     conditional_interrupt(ch);
 375     conditional_branch(ch);
 376
 377 wait:
 378     ch->processing = 0;
 379     if ((ch->regs[DBDMA_STATUS] & cpu_to_be32(RUN)) &&
 380         (ch->regs[DBDMA_STATUS] & cpu_to_be32(ACTIVE)))
 381         channel_run(ch);
 382 }
 383
 384 static void start_output(DBDMA_channel *ch, int key, uint32_t addr,
 385                         uint16_t req_count, int is_last)
 386 {
 387     DBDMA_DPRINTF("start_output\n");
 388
 389     /* KEY_REGS, KEY_DEVICE and KEY_STREAM
 390      * are not implemented in the mac-io chip
 391      */
 392
 393     DBDMA_DPRINTF("addr 0x%x key 0x%x\n", addr, key);
 394     if (!addr || key > KEY_STREAM3) {
 395         kill_channel(ch);
 396         return;
 397     }
 398
 399     ch->io.addr = addr;
 400     ch->io.len = req_count;
 401     ch->io.is_last = is_last;
 402     ch->io.dma_end = dbdma_end;
 403     ch->io.is_dma_out = 1;
 404     ch->processing = 1;
 405     ch->rw(&ch->io);
 406 }
 407
 408 static void start_input(DBDMA_channel *ch, int key, uint32_t addr,
 409                        uint16_t req_count, int is_last)
 410 {
 411     DBDMA_DPRINTF("start_input\n");
 412
 413     /* KEY_REGS, KEY_DEVICE and KEY_STREAM
 414      * are not implemented in the mac-io chip
 415      */
 416
 417     if (!addr || key > KEY_STREAM3) {
 418         kill_channel(ch);
 419         return;
 420     }
 421
 422     ch->io.addr = addr;
 423     ch->io.len = req_count;
 424     ch->io.is_last = is_last;
 425     ch->io.dma_end = dbdma_end;
 426     ch->io.is_dma_out = 0;
 427     ch->processing = 1;
 428     ch->rw(&ch->io);
 429 }
 430
 431 static void load_word(DBDMA_channel *ch, int key, uint32_t addr,
 432                      uint16_t len)
 433 {
 434     dbdma_cmd *current = &ch->current;
 435     uint32_t val;
 436
 437     DBDMA_DPRINTF("load_word\n");
 438
 439     /* only implements KEY_SYSTEM */
 440
 441     if (key != KEY_SYSTEM) {
 442         printf("DBDMA: LOAD_WORD, unimplemented key %x\n", key);
 443         kill_channel(ch);
 444         return;
 445     }
 446
 447     cpu_physical_memory_read(addr, (uint8_t*)&val, len);
 448
 449     if (len == 2)
 450         val = (val << 16) | (current->cmd_dep & 0x0000ffff);
 451     else if (len == 1)
 452         val = (val << 24) | (current->cmd_dep & 0x00ffffff);
 453
 454     current->cmd_dep = val;
 455
 456     if (conditional_wait(ch))
 457         goto wait;
 458
 459     current->xfer_status = cpu_to_le16(be32_to_cpu(ch->regs[DBDMA_STATUS]));
 460     dbdma_cmdptr_save(ch);
 461     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~FLUSH);
 462
 463     conditional_interrupt(ch);
 464     next(ch);
 465
 466 wait:
 467     qemu_bh_schedule(dbdma_bh);
 468 }
 469
 470 static void store_word(DBDMA_channel *ch, int key, uint32_t addr,
 471                       uint16_t len)
 472 {
 473     dbdma_cmd *current = &ch->current;
 474     uint32_t val;
 475
 476     DBDMA_DPRINTF("store_word\n");
 477
 478     /* only implements KEY_SYSTEM */
 479
 480     if (key != KEY_SYSTEM) {
 481         printf("DBDMA: STORE_WORD, unimplemented key %x\n", key);
 482         kill_channel(ch);
 483         return;
 484     }
 485
 486     val = current->cmd_dep;
 487     if (len == 2)
 488         val >>= 16;
 489     else if (len == 1)
 490         val >>= 24;
 491
 492     cpu_physical_memory_write(addr, (uint8_t*)&val, len);
 493
 494     if (conditional_wait(ch))
 495         goto wait;
 496
 497     current->xfer_status = cpu_to_le16(be32_to_cpu(ch->regs[DBDMA_STATUS]));
 498     dbdma_cmdptr_save(ch);
 499     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~FLUSH);
 500
 501     conditional_interrupt(ch);
 502     next(ch);
 503
 504 wait:
 505     qemu_bh_schedule(dbdma_bh);
 506 }
 507
 508 static void nop(DBDMA_channel *ch)
 509 {
 510     dbdma_cmd *current = &ch->current;
 511
 512     if (conditional_wait(ch))
 513         goto wait;
 514
 515     current->xfer_status = cpu_to_le16(be32_to_cpu(ch->regs[DBDMA_STATUS]));
 516     dbdma_cmdptr_save(ch);
 517
 518     conditional_interrupt(ch);
 519     conditional_branch(ch);
 520
 521 wait:
 522     qemu_bh_schedule(dbdma_bh);
 523 }
 524
 525 static void stop(DBDMA_channel *ch)
 526 {
 527     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~(ACTIVE|DEAD|FLUSH));
 528
 529     /* the stop command does not increment command pointer */
 530 }
 531
 532 static void channel_run(DBDMA_channel *ch)
 533 {
 534     dbdma_cmd *current = &ch->current;
 535     uint16_t cmd, key;
 536     uint16_t req_count;
 537     uint32_t phy_addr;
 538
 539     DBDMA_DPRINTF("channel_run\n");
 540     dump_dbdma_cmd(current);
 541
 542     /* clear WAKE flag at command fetch */
 543
 544     ch->regs[DBDMA_STATUS] &= cpu_to_be32(~WAKE);
 545
 546     cmd = le16_to_cpu(current->command) & COMMAND_MASK;
 547
 548     switch (cmd) {
 549     case DBDMA_NOP:
 550         nop(ch);
 551         return;
 552
 553     case DBDMA_STOP:
 554         stop(ch);
 555         return;
 556     }
 557
 558     key = le16_to_cpu(current->command) & 0x0700;
 559     req_count = le16_to_cpu(current->req_count);
 560     phy_addr = le32_to_cpu(current->phy_addr);
 561
 562     if (key == KEY_STREAM4) {
 563         printf("command %x, invalid key 4\n", cmd);
 564         kill_channel(ch);
 565         return;
 566     }
 567
 568     switch (cmd) {
 569     case OUTPUT_MORE:
 570         start_output(ch, key, phy_addr, req_count, 0);
 571         return;
 572
 573     case OUTPUT_LAST:
 574         start_output(ch, key, phy_addr, req_count, 1);
 575         return;
 576
 577     case INPUT_MORE:
 578         start_input(ch, key, phy_addr, req_count, 0);
 579         return;
 580
 581     case INPUT_LAST:
 582         start_input(ch, key, phy_addr, req_count, 1);
 583         return;
 584     }
 585
 586     if (key < KEY_REGS) {
 587         printf("command %x, invalid key %x\n", cmd, key);
 588         key = KEY_SYSTEM;
 589     }
 590
 591     /* for LOAD_WORD and STORE_WORD, req_count is on 3 bits
 592      * and BRANCH is invalid
 593      */
 594
 595     req_count = req_count & 0x0007;
 596     if (req_count & 0x4) {
 597         req_count = 4;
 598         phy_addr &= ~3;
 599     } else if (req_count & 0x2) {
 600         req_count = 2;
 601         phy_addr &= ~1;
 602     } else
 603         req_count = 1;
 604
 605     switch (cmd) {
 606     case LOAD_WORD:
 607         load_word(ch, key, phy_addr, req_count);
 608         return;
 609
 610     case STORE_WORD:
 611         store_word(ch, key, phy_addr, req_count);
 612         return;
 613     }
 614 }
 615
 616 static void DBDMA_run (DBDMA_channel *ch)
 617 {
 618     int channel;
 619
 620     for (channel = 0; channel < DBDMA_CHANNELS; channel++, ch++) {
 621             uint32_t status = be32_to_cpu(ch->regs[DBDMA_STATUS]);
 622             if (!ch->processing && (status & RUN) && (status & ACTIVE))
 623                 channel_run(ch);
 624     }
 625 }
 626
 627 static void DBDMA_run_bh(void *opaque)
 628 {
 629     DBDMA_channel *ch = opaque;
 630
 631     DBDMA_DPRINTF("DBDMA_run_bh\n");
 632
 633     DBDMA_run(ch);
 634 }
 635
 636 void DBDMA_register_channel(void *dbdma, int nchan, qemu_irq irq,
 637                             DBDMA_rw rw, DBDMA_flush flush,
 638                             void *opaque)
 639 {
 640     DBDMA_channel *ch = ( DBDMA_channel *)dbdma + nchan;
 641
 642     DBDMA_DPRINTF("DBDMA_register_channel 0x%x\n", nchan);
 643
 644     ch->irq = irq;
 645     ch->channel = nchan;
 646     ch->rw = rw;
 647     ch->flush = flush;
 648     ch->io.opaque = opaque;
 649     ch->io.channel = ch;
 650 }
 651
 652 void DBDMA_schedule(void)
 653 {
 654     qemu_notify_event();
 655 }
 656
 657 static void
 658 dbdma_control_write(DBDMA_channel *ch)
 659 {
 660     uint16_t mask, value;
 661     uint32_t status;
 662
 663     mask = (be32_to_cpu(ch->regs[DBDMA_CONTROL]) >> 16) & 0xffff;
 664     value = be32_to_cpu(ch->regs[DBDMA_CONTROL]) & 0xffff;
 665
 666     value &= (RUN | PAUSE | FLUSH | WAKE | DEVSTAT);
 667
 668     status = be32_to_cpu(ch->regs[DBDMA_STATUS]);
 669
 670     status = (value & mask) | (status & ~mask);
 671
 672     if (status & WAKE)
 673         status |= ACTIVE;
 674     if (status & RUN) {
 675         status |= ACTIVE;
 676         status &= ~DEAD;
 677     }
 678     if (status & PAUSE)
 679         status &= ~ACTIVE;
 680     if ((be32_to_cpu(ch->regs[DBDMA_STATUS]) & RUN) && !(status & RUN)) {
 681         /* RUN is cleared */
 682         status &= ~(ACTIVE|DEAD);
 683     }
 684
 685     DBDMA_DPRINTF("    status 0x%08x\n", status);
 686
 687     ch->regs[DBDMA_STATUS] = cpu_to_be32(status);
 688
 689     if (status & ACTIVE)
 690         qemu_bh_schedule(dbdma_bh);
 691     if (status & FLUSH)
 692         ch->flush(&ch->io);
 693 }
 694
 695 static void dbdma_writel (void *opaque,
 696                           target_phys_addr_t addr, uint32_t value)
 697 {
 698     int channel = addr >> DBDMA_CHANNEL_SHIFT;
 699     DBDMA_channel *ch = (DBDMA_channel *)opaque + channel;
 700     int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
 701
 702     DBDMA_DPRINTF("writel 0x" TARGET_FMT_plx " <= 0x%08x\n", addr, value);
 703     DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
 704                   (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
 705
 706     /* cmdptr cannot be modified if channel is RUN or ACTIVE */
 707
 708     if (reg == DBDMA_CMDPTR_LO &&
 709         (ch->regs[DBDMA_STATUS] & cpu_to_be32(RUN | ACTIVE)))
 710         return;
 711
 712     ch->regs[reg] = value;
 713
 714     switch(reg) {
 715     case DBDMA_CONTROL:
 716         dbdma_control_write(ch);
 717         break;
 718     case DBDMA_CMDPTR_LO:
 719         /* 16-byte aligned */
 720         ch->regs[DBDMA_CMDPTR_LO] &= cpu_to_be32(~0xf);
 721         dbdma_cmdptr_load(ch);
 722         break;
 723     case DBDMA_STATUS:
 724     case DBDMA_INTR_SEL:
 725     case DBDMA_BRANCH_SEL:
 726     case DBDMA_WAIT_SEL:
 727         /* nothing to do */
 728         break;
 729     case DBDMA_XFER_MODE:
 730     case DBDMA_CMDPTR_HI:
 731     case DBDMA_DATA2PTR_HI:
 732     case DBDMA_DATA2PTR_LO:
 733     case DBDMA_ADDRESS_HI:
 734     case DBDMA_BRANCH_ADDR_HI:
 735     case DBDMA_RES1:
 736     case DBDMA_RES2:
 737     case DBDMA_RES3:
 738     case DBDMA_RES4:
 739         /* unused */
 740         break;
 741     }
 742 }
 743
 744 static uint32_t dbdma_readl (void *opaque, target_phys_addr_t addr)
 745 {
 746     uint32_t value;
 747     int channel = addr >> DBDMA_CHANNEL_SHIFT;
 748     DBDMA_channel *ch = (DBDMA_channel *)opaque + channel;
 749     int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
 750
 751     value = ch->regs[reg];
 752
 753     DBDMA_DPRINTF("readl 0x" TARGET_FMT_plx " => 0x%08x\n", addr, value);
 754     DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
 755                   (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
 756
 757     switch(reg) {
 758     case DBDMA_CONTROL:
 759         value = 0;
 760         break;
 761     case DBDMA_STATUS:
 762     case DBDMA_CMDPTR_LO:
 763     case DBDMA_INTR_SEL:
 764     case DBDMA_BRANCH_SEL:
 765     case DBDMA_WAIT_SEL:
 766         /* nothing to do */
 767         break;
 768     case DBDMA_XFER_MODE:
 769     case DBDMA_CMDPTR_HI:
 770     case DBDMA_DATA2PTR_HI:
 771     case DBDMA_DATA2PTR_LO:
 772     case DBDMA_ADDRESS_HI:
 773     case DBDMA_BRANCH_ADDR_HI:
 774         /* unused */
 775         value = 0;
 776         break;
 777     case DBDMA_RES1:
 778     case DBDMA_RES2:
 779     case DBDMA_RES3:
 780     case DBDMA_RES4:
 781         /* reserved */
 782         break;
 783     }
 784
 785     return value;
 786 }
 787
 788 static CPUWriteMemoryFunc *dbdma_write[] = {
 789     NULL,
 790     NULL,
 791     dbdma_writel,
 792 };
 793
 794 static CPUReadMemoryFunc *dbdma_read[] = {
 795     NULL,
 796     NULL,
 797     dbdma_readl,
 798 };
 799
 800 static void dbdma_save(QEMUFile *f, void *opaque)
 801 {
 802     DBDMA_channel *s = opaque;
 803     unsigned int i, j;
 804
 805     for (i = 0; i < DBDMA_CHANNELS; i++)
 806         for (j = 0; j < DBDMA_REGS; j++)
 807             qemu_put_be32s(f, &s[i].regs[j]);
 808 }
 809
 810 static int dbdma_load(QEMUFile *f, void *opaque, int version_id)
 811 {
 812     DBDMA_channel *s = opaque;
 813     unsigned int i, j;
 814
 815     if (version_id != 2)
 816         return -EINVAL;
 817
 818     for (i = 0; i < DBDMA_CHANNELS; i++)
 819         for (j = 0; j < DBDMA_REGS; j++)
 820             qemu_get_be32s(f, &s[i].regs[j]);
 821
 822     return 0;
 823 }
 824
 825 static void dbdma_reset(void *opaque)
 826 {
 827     DBDMA_channel *s = opaque;
 828     int i;
 829
 830     for (i = 0; i < DBDMA_CHANNELS; i++)
 831         memset(s[i].regs, 0, DBDMA_SIZE);
 832 }
 833
 834 void* DBDMA_init (int *dbdma_mem_index)
 835 {
 836     DBDMA_channel *s;
 837
 838     s = qemu_mallocz(sizeof(DBDMA_channel) * DBDMA_CHANNELS);
 839
 840     *dbdma_mem_index = cpu_register_io_memory(0, dbdma_read, dbdma_write, s);
 841     register_savevm("dbdma", -1, 1, dbdma_save, dbdma_load, s);
 842     qemu_register_reset(dbdma_reset, s);
 843     dbdma_reset(s);
 844
 845     dbdma_bh = qemu_bh_new(DBDMA_run_bh, s);
 846
 847     return s;
 848 }