drivers/cdrom/gdrom.c

   1 /* GD ROM driver for the SEGA Dreamcast
   2  * copyright Adrian McMenamin, 2007
   3  * With thanks to Marcus Comstedt and Nathan Keynes
   4  * for work in reversing PIO and DMA
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  */
  21
  22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/fs.h>
  27 #include <linux/kernel.h>
  28 #include <linux/list.h>
  29 #include <linux/slab.h>
  30 #include <linux/dma-mapping.h>
  31 #include <linux/cdrom.h>
  32 #include <linux/genhd.h>
  33 #include <linux/bio.h>
  34 #include <linux/blkdev.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/device.h>
  37 #include <linux/wait.h>
  38 #include <linux/workqueue.h>
  39 #include <linux/platform_device.h>
  40 #include <scsi/scsi.h>
  41 #include <asm/io.h>
  42 #include <asm/dma.h>
  43 #include <asm/delay.h>
  44 #include <mach/dma.h>
  45 #include <mach/sysasic.h>
  46
  47 #define GDROM_DEV_NAME "gdrom"
  48 #define GD_SESSION_OFFSET 150
  49
  50 /* GD Rom commands */
  51 #define GDROM_COM_SOFTRESET 0x08
  52 #define GDROM_COM_EXECDIAG 0x90
  53 #define GDROM_COM_PACKET 0xA0
  54 #define GDROM_COM_IDDEV 0xA1
  55
  56 /* GD Rom registers */
  57 #define GDROM_BASE_REG                  0xA05F7000
  58 #define GDROM_ALTSTATUS_REG             (GDROM_BASE_REG + 0x18)
  59 #define GDROM_DATA_REG                  (GDROM_BASE_REG + 0x80)
  60 #define GDROM_ERROR_REG         (GDROM_BASE_REG + 0x84)
  61 #define GDROM_INTSEC_REG                (GDROM_BASE_REG + 0x88)
  62 #define GDROM_SECNUM_REG                (GDROM_BASE_REG + 0x8C)
  63 #define GDROM_BCL_REG                   (GDROM_BASE_REG + 0x90)
  64 #define GDROM_BCH_REG                   (GDROM_BASE_REG + 0x94)
  65 #define GDROM_DSEL_REG                  (GDROM_BASE_REG + 0x98)
  66 #define GDROM_STATUSCOMMAND_REG (GDROM_BASE_REG + 0x9C)
  67 #define GDROM_RESET_REG         (GDROM_BASE_REG + 0x4E4)
  68
  69 #define GDROM_DMA_STARTADDR_REG (GDROM_BASE_REG + 0x404)
  70 #define GDROM_DMA_LENGTH_REG            (GDROM_BASE_REG + 0x408)
  71 #define GDROM_DMA_DIRECTION_REG (GDROM_BASE_REG + 0x40C)
  72 #define GDROM_DMA_ENABLE_REG            (GDROM_BASE_REG + 0x414)
  73 #define GDROM_DMA_STATUS_REG            (GDROM_BASE_REG + 0x418)
  74 #define GDROM_DMA_WAIT_REG              (GDROM_BASE_REG + 0x4A0)
  75 #define GDROM_DMA_ACCESS_CTRL_REG       (GDROM_BASE_REG + 0x4B8)
  76
  77 #define GDROM_HARD_SECTOR       2048
  78 #define BLOCK_LAYER_SECTOR      512
  79 #define GD_TO_BLK               4
  80
  81 #define GDROM_DEFAULT_TIMEOUT   (HZ * 7)
  82
  83 static const struct {
  84         int sense_key;
  85         const char * const text;
  86 } sense_texts[] = {
  87         {NO_SENSE, "OK"},
  88         {RECOVERED_ERROR, "Recovered from error"},
  89         {NOT_READY, "Device not ready"},
  90         {MEDIUM_ERROR, "Disk not ready"},
  91         {HARDWARE_ERROR, "Hardware error"},
  92         {ILLEGAL_REQUEST, "Command has failed"},
  93         {UNIT_ATTENTION, "Device needs attention - disk may have been changed"},
  94         {DATA_PROTECT, "Data protection error"},
  95         {ABORTED_COMMAND, "Command aborted"},
  96 };
  97
  98 static struct platform_device *pd;
  99 static int gdrom_major;
 100 static DECLARE_WAIT_QUEUE_HEAD(command_queue);
 101 static DECLARE_WAIT_QUEUE_HEAD(request_queue);
 102
 103 static DEFINE_SPINLOCK(gdrom_lock);
 104 static void gdrom_readdisk_dma(struct work_struct *work);
 105 static DECLARE_WORK(work, gdrom_readdisk_dma);
 106 static LIST_HEAD(gdrom_deferred);
 107
 108 struct gdromtoc {
 109         unsigned int entry[99];
 110         unsigned int first, last;
 111         unsigned int leadout;
 112 };
 113
 114 static struct gdrom_unit {
 115         struct gendisk *disk;
 116         struct cdrom_device_info *cd_info;
 117         int status;
 118         int pending;
 119         int transfer;
 120         char disk_type;
 121         struct gdromtoc *toc;
 122         struct request_queue *gdrom_rq;
 123 } gd;
 124
 125 struct gdrom_id {
 126         char mid;
 127         char modid;
 128         char verid;
 129         char padA[13];
 130         char mname[16];
 131         char modname[16];
 132         char firmver[16];
 133         char padB[16];
 134 };
 135
 136 static int gdrom_getsense(short *bufstring);
 137 static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
 138         struct packet_command *command);
 139 static int gdrom_hardreset(struct cdrom_device_info *cd_info);
 140
 141 static bool gdrom_is_busy(void)
 142 {
 143         return (ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) != 0;
 144 }
 145
 146 static bool gdrom_data_request(void)
 147 {
 148         return (ctrl_inb(GDROM_ALTSTATUS_REG) & 0x88) == 8;
 149 }
 150
 151 static bool gdrom_wait_clrbusy(void)
 152 {
 153         unsigned long timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 154         while ((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) &&
 155                 (time_before(jiffies, timeout)))
 156                 cpu_relax();
 157         return time_before(jiffies, timeout + 1);
 158 }
 159
 160 static bool gdrom_wait_busy_sleeps(void)
 161 {
 162         unsigned long timeout;
 163         /* Wait to get busy first */
 164         timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 165         while (!gdrom_is_busy() && time_before(jiffies, timeout))
 166                 cpu_relax();
 167         /* Now wait for busy to clear */
 168         return gdrom_wait_clrbusy();
 169 }
 170
 171 static void gdrom_identifydevice(void *buf)
 172 {
 173         int c;
 174         short *data = buf;
 175         /* If the device won't clear it has probably
 176         * been hit by a serious failure - but we'll
 177         * try to return a sense key even so */
 178         if (!gdrom_wait_clrbusy()) {
 179                 gdrom_getsense(NULL);
 180                 return;
 181         }
 182         ctrl_outb(GDROM_COM_IDDEV, GDROM_STATUSCOMMAND_REG);
 183         if (!gdrom_wait_busy_sleeps()) {
 184                 gdrom_getsense(NULL);
 185                 return;
 186         }
 187         /* now read in the data */
 188         for (c = 0; c < 40; c++)
 189                 data[c] = ctrl_inw(GDROM_DATA_REG);
 190 }
 191
 192 static void gdrom_spicommand(void *spi_string, int buflen)
 193 {
 194         short *cmd = spi_string;
 195         unsigned long timeout;
 196
 197         /* ensure IRQ_WAIT is set */
 198         ctrl_outb(0x08, GDROM_ALTSTATUS_REG);
 199         /* specify how many bytes we expect back */
 200         ctrl_outb(buflen & 0xFF, GDROM_BCL_REG);
 201         ctrl_outb((buflen >> 8) & 0xFF, GDROM_BCH_REG);
 202         /* other parameters */
 203         ctrl_outb(0, GDROM_INTSEC_REG);
 204         ctrl_outb(0, GDROM_SECNUM_REG);
 205         ctrl_outb(0, GDROM_ERROR_REG);
 206         /* Wait until we can go */
 207         if (!gdrom_wait_clrbusy()) {
 208                 gdrom_getsense(NULL);
 209                 return;
 210         }
 211         timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 212         ctrl_outb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
 213         while (!gdrom_data_request() && time_before(jiffies, timeout))
 214                 cpu_relax();
 215         if (!time_before(jiffies, timeout + 1)) {
 216                 gdrom_getsense(NULL);
 217                 return;
 218         }
 219         outsw(GDROM_DATA_REG, cmd, 6);
 220 }
 221
 222
 223 /* gdrom_command_executediagnostic:
 224  * Used to probe for presence of working GDROM
 225  * Restarts GDROM device and then applies standard ATA 3
 226  * Execute Diagnostic Command: a return of '1' indicates device 0
 227  * present and device 1 absent
 228  */
 229 static char gdrom_execute_diagnostic(void)
 230 {
 231         gdrom_hardreset(gd.cd_info);
 232         if (!gdrom_wait_clrbusy())
 233                 return 0;
 234         ctrl_outb(GDROM_COM_EXECDIAG, GDROM_STATUSCOMMAND_REG);
 235         if (!gdrom_wait_busy_sleeps())
 236                 return 0;
 237         return ctrl_inb(GDROM_ERROR_REG);
 238 }
 239
 240 /*
 241  * Prepare disk command
 242  * byte 0 = 0x70
 243  * byte 1 = 0x1f
 244  */
 245 static int gdrom_preparedisk_cmd(void)
 246 {
 247         struct packet_command *spin_command;
 248         spin_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 249         if (!spin_command)
 250                 return -ENOMEM;
 251         spin_command->cmd[0] = 0x70;
 252         spin_command->cmd[2] = 0x1f;
 253         spin_command->buflen = 0;
 254         gd.pending = 1;
 255         gdrom_packetcommand(gd.cd_info, spin_command);
 256         /* 60 second timeout */
 257         wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 258                 GDROM_DEFAULT_TIMEOUT);
 259         gd.pending = 0;
 260         kfree(spin_command);
 261         if (gd.status & 0x01) {
 262                 /* log an error */
 263                 gdrom_getsense(NULL);
 264                 return -EIO;
 265         }
 266         return 0;
 267 }
 268
 269 /*
 270  * Read TOC command
 271  * byte 0 = 0x14
 272  * byte 1 = session
 273  * byte 3 = sizeof TOC >> 8  ie upper byte
 274  * byte 4 = sizeof TOC & 0xff ie lower byte
 275  */
 276 static int gdrom_readtoc_cmd(struct gdromtoc *toc, int session)
 277 {
 278         int tocsize;
 279         struct packet_command *toc_command;
 280         int err = 0;
 281
 282         toc_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 283         if (!toc_command)
 284                 return -ENOMEM;
 285         tocsize = sizeof(struct gdromtoc);
 286         toc_command->cmd[0] = 0x14;
 287         toc_command->cmd[1] = session;
 288         toc_command->cmd[3] = tocsize >> 8;
 289         toc_command->cmd[4] = tocsize & 0xff;
 290         toc_command->buflen = tocsize;
 291         if (gd.pending) {
 292                 err = -EBUSY;
 293                 goto cleanup_readtoc_final;
 294         }
 295         gd.pending = 1;
 296         gdrom_packetcommand(gd.cd_info, toc_command);
 297         wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 298                 GDROM_DEFAULT_TIMEOUT);
 299         if (gd.pending) {
 300                 err = -EINVAL;
 301                 goto cleanup_readtoc;
 302         }
 303         insw(GDROM_DATA_REG, toc, tocsize/2);
 304         if (gd.status & 0x01)
 305                 err = -EINVAL;
 306
 307 cleanup_readtoc:
 308         gd.pending = 0;
 309 cleanup_readtoc_final:
 310         kfree(toc_command);
 311         return err;
 312 }
 313
 314 /* TOC helpers */
 315 static int get_entry_lba(int track)
 316 {
 317         return (cpu_to_be32(track & 0xffffff00) - GD_SESSION_OFFSET);
 318 }
 319
 320 static int get_entry_q_ctrl(int track)
 321 {
 322         return (track & 0x000000f0) >> 4;
 323 }
 324
 325 static int get_entry_track(int track)
 326 {
 327         return (track & 0x0000ff00) >> 8;
 328 }
 329
 330 static int gdrom_get_last_session(struct cdrom_device_info *cd_info,
 331         struct cdrom_multisession *ms_info)
 332 {
 333         int fentry, lentry, track, data, tocuse, err;
 334         if (!gd.toc)
 335                 return -ENOMEM;
 336         tocuse = 1;
 337         /* Check if GD-ROM */
 338         err = gdrom_readtoc_cmd(gd.toc, 1);
 339         /* Not a GD-ROM so check if standard CD-ROM */
 340         if (err) {
 341                 tocuse = 0;
 342                 err = gdrom_readtoc_cmd(gd.toc, 0);
 343                 if (err) {
 344                         pr_info("Could not get CD table of contents\n");
 345                         return -ENXIO;
 346                 }
 347         }
 348
 349         fentry = get_entry_track(gd.toc->first);
 350         lentry = get_entry_track(gd.toc->last);
 351         /* Find the first data track */
 352         track = get_entry_track(gd.toc->last);
 353         do {
 354                 data = gd.toc->entry[track - 1];
 355                 if (get_entry_q_ctrl(data))
 356                         break;  /* ie a real data track */
 357                 track--;
 358         } while (track >= fentry);
 359
 360         if ((track > 100) || (track < get_entry_track(gd.toc->first))) {
 361                 pr_info("No data on the last session of the CD\n");
 362                 gdrom_getsense(NULL);
 363                 return -ENXIO;
 364         }
 365
 366         ms_info->addr_format = CDROM_LBA;
 367         ms_info->addr.lba = get_entry_lba(data);
 368         ms_info->xa_flag = 1;
 369         return 0;
 370 }
 371
 372 static int gdrom_open(struct cdrom_device_info *cd_info, int purpose)
 373 {
 374         /* spin up the disk */
 375         return gdrom_preparedisk_cmd();
 376 }
 377
 378 /* this function is required even if empty */
 379 static void gdrom_release(struct cdrom_device_info *cd_info)
 380 {
 381 }
 382
 383 static int gdrom_drivestatus(struct cdrom_device_info *cd_info, int ignore)
 384 {
 385         /* read the sense key */
 386         char sense = ctrl_inb(GDROM_ERROR_REG);
 387         sense &= 0xF0;
 388         if (sense == 0)
 389                 return CDS_DISC_OK;
 390         if (sense == 0x20)
 391                 return CDS_DRIVE_NOT_READY;
 392         /* default */
 393         return CDS_NO_INFO;
 394 }
 395
 396 static int gdrom_mediachanged(struct cdrom_device_info *cd_info, int ignore)
 397 {
 398         /* check the sense key */
 399         return (ctrl_inb(GDROM_ERROR_REG) & 0xF0) == 0x60;
 400 }
 401
 402 /* reset the G1 bus */
 403 static int gdrom_hardreset(struct cdrom_device_info *cd_info)
 404 {
 405         int count;
 406         ctrl_outl(0x1fffff, GDROM_RESET_REG);
 407         for (count = 0xa0000000; count < 0xa0200000; count += 4)
 408                 ctrl_inl(count);
 409         return 0;
 410 }
 411
 412 /* keep the function looking like the universal
 413  * CD Rom specification  - returning int */
 414 static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
 415         struct packet_command *command)
 416 {
 417         gdrom_spicommand(&command->cmd, command->buflen);
 418         return 0;
 419 }
 420
 421 /* Get Sense SPI command
 422  * From Marcus Comstedt
 423  * cmd = 0x13
 424  * cmd + 4 = length of returned buffer
 425  * Returns 5 16 bit words
 426  */
 427 static int gdrom_getsense(short *bufstring)
 428 {
 429         struct packet_command *sense_command;
 430         short sense[5];
 431         int sense_key;
 432         int err = -EIO;
 433
 434         sense_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 435         if (!sense_command)
 436                 return -ENOMEM;
 437         sense_command->cmd[0] = 0x13;
 438         sense_command->cmd[4] = 10;
 439         sense_command->buflen = 10;
 440         /* even if something is pending try to get
 441         * the sense key if possible */
 442         if (gd.pending && !gdrom_wait_clrbusy()) {
 443                 err = -EBUSY;
 444                 goto cleanup_sense_final;
 445         }
 446         gd.pending = 1;
 447         gdrom_packetcommand(gd.cd_info, sense_command);
 448         wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 449                 GDROM_DEFAULT_TIMEOUT);
 450         if (gd.pending)
 451                 goto cleanup_sense;
 452         insw(GDROM_DATA_REG, &sense, sense_command->buflen/2);
 453         if (sense[1] & 40) {
 454                 pr_info("Drive not ready - command aborted\n");
 455                 goto cleanup_sense;
 456         }
 457         sense_key = sense[1] & 0x0F;
 458         if (sense_key < ARRAY_SIZE(sense_texts))
 459                 pr_info("%s\n", sense_texts[sense_key].text);
 460         else
 461                 pr_err("Unknown sense key: %d\n", sense_key);
 462         if (bufstring) /* return addional sense data */
 463                 memcpy(bufstring, &sense[4], 2);
 464         if (sense_key < 2)
 465                 err = 0;
 466
 467 cleanup_sense:
 468         gd.pending = 0;
 469 cleanup_sense_final:
 470         kfree(sense_command);
 471         return err;
 472 }
 473
 474 static int gdrom_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
 475                              void *arg)
 476 {
 477         return -EINVAL;
 478 }
 479
 480 static struct cdrom_device_ops gdrom_ops = {
 481         .open                   = gdrom_open,
 482         .release                = gdrom_release,
 483         .drive_status           = gdrom_drivestatus,
 484         .media_changed          = gdrom_mediachanged,
 485         .get_last_session       = gdrom_get_last_session,
 486         .reset                  = gdrom_hardreset,
 487         .audio_ioctl            = gdrom_audio_ioctl,
 488         .capability             = CDC_MULTI_SESSION | CDC_MEDIA_CHANGED |
 489                                   CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R,
 490         .n_minors               = 1,
 491 };
 492
 493 static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
 494 {
 495         return cdrom_open(gd.cd_info, bdev, mode);
 496 }
 497
 498 static int gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
 499 {
 500         cdrom_release(gd.cd_info, mode);
 501         return 0;
 502 }
 503
 504 static int gdrom_bdops_mediachanged(struct gendisk *disk)
 505 {
 506         return cdrom_media_changed(gd.cd_info);
 507 }
 508
 509 static int gdrom_bdops_ioctl(struct block_device *bdev, fmode_t mode,
 510         unsigned cmd, unsigned long arg)
 511 {
 512         return cdrom_ioctl(gd.cd_info, bdev, mode, cmd, arg);
 513 }
 514
 515 static const struct block_device_operations gdrom_bdops = {
 516         .owner                  = THIS_MODULE,
 517         .open                   = gdrom_bdops_open,
 518         .release                = gdrom_bdops_release,
 519         .media_changed          = gdrom_bdops_mediachanged,
 520         .locked_ioctl           = gdrom_bdops_ioctl,
 521 };
 522
 523 static irqreturn_t gdrom_command_interrupt(int irq, void *dev_id)
 524 {
 525         gd.status = ctrl_inb(GDROM_STATUSCOMMAND_REG);
 526         if (gd.pending != 1)
 527                 return IRQ_HANDLED;
 528         gd.pending = 0;
 529         wake_up_interruptible(&command_queue);
 530         return IRQ_HANDLED;
 531 }
 532
 533 static irqreturn_t gdrom_dma_interrupt(int irq, void *dev_id)
 534 {
 535         gd.status = ctrl_inb(GDROM_STATUSCOMMAND_REG);
 536         if (gd.transfer != 1)
 537                 return IRQ_HANDLED;
 538         gd.transfer = 0;
 539         wake_up_interruptible(&request_queue);
 540         return IRQ_HANDLED;
 541 }
 542
 543 static int __devinit gdrom_set_interrupt_handlers(void)
 544 {
 545         int err;
 546
 547         err = request_irq(HW_EVENT_GDROM_CMD, gdrom_command_interrupt,
 548                 IRQF_DISABLED, "gdrom_command", &gd);
 549         if (err)
 550                 return err;
 551         err = request_irq(HW_EVENT_GDROM_DMA, gdrom_dma_interrupt,
 552                 IRQF_DISABLED, "gdrom_dma", &gd);
 553         if (err)
 554                 free_irq(HW_EVENT_GDROM_CMD, &gd);
 555         return err;
 556 }
 557
 558 /* Implement DMA read using SPI command
 559  * 0 -> 0x30
 560  * 1 -> mode
 561  * 2 -> block >> 16
 562  * 3 -> block >> 8
 563  * 4 -> block
 564  * 8 -> sectors >> 16
 565  * 9 -> sectors >> 8
 566  * 10 -> sectors
 567  */
 568 static void gdrom_readdisk_dma(struct work_struct *work)
 569 {
 570         int err, block, block_cnt;
 571         struct packet_command *read_command;
 572         struct list_head *elem, *next;
 573         struct request *req;
 574         unsigned long timeout;
 575
 576         if (list_empty(&gdrom_deferred))
 577                 return;
 578         read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 579         if (!read_command)
 580                 return; /* get more memory later? */
 581         read_command->cmd[0] = 0x30;
 582         read_command->cmd[1] = 0x20;
 583         spin_lock(&gdrom_lock);
 584         list_for_each_safe(elem, next, &gdrom_deferred) {
 585                 req = list_entry(elem, struct request, queuelist);
 586                 spin_unlock(&gdrom_lock);
 587                 block = blk_rq_pos(req)/GD_TO_BLK + GD_SESSION_OFFSET;
 588                 block_cnt = blk_rq_sectors(req)/GD_TO_BLK;
 589                 ctrl_outl(virt_to_phys(req->buffer), GDROM_DMA_STARTADDR_REG);
 590                 ctrl_outl(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);
 591                 ctrl_outl(1, GDROM_DMA_DIRECTION_REG);
 592                 ctrl_outl(1, GDROM_DMA_ENABLE_REG);
 593                 read_command->cmd[2] = (block >> 16) & 0xFF;
 594                 read_command->cmd[3] = (block >> 8) & 0xFF;
 595                 read_command->cmd[4] = block & 0xFF;
 596                 read_command->cmd[8] = (block_cnt >> 16) & 0xFF;
 597                 read_command->cmd[9] = (block_cnt >> 8) & 0xFF;
 598                 read_command->cmd[10] = block_cnt & 0xFF;
 599                 /* set for DMA */
 600                 ctrl_outb(1, GDROM_ERROR_REG);
 601                 /* other registers */
 602                 ctrl_outb(0, GDROM_SECNUM_REG);
 603                 ctrl_outb(0, GDROM_BCL_REG);
 604                 ctrl_outb(0, GDROM_BCH_REG);
 605                 ctrl_outb(0, GDROM_DSEL_REG);
 606                 ctrl_outb(0, GDROM_INTSEC_REG);
 607                 /* Wait for registers to reset after any previous activity */
 608                 timeout = jiffies + HZ / 2;
 609                 while (gdrom_is_busy() && time_before(jiffies, timeout))
 610                         cpu_relax();
 611                 ctrl_outb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
 612                 timeout = jiffies + HZ / 2;
 613                 /* Wait for packet command to finish */
 614                 while (gdrom_is_busy() && time_before(jiffies, timeout))
 615                         cpu_relax();
 616                 gd.pending = 1;
 617                 gd.transfer = 1;
 618                 outsw(GDROM_DATA_REG, &read_command->cmd, 6);
 619                 timeout = jiffies + HZ / 2;
 620                 /* Wait for any pending DMA to finish */
 621                 while (ctrl_inb(GDROM_DMA_STATUS_REG) &&
 622                         time_before(jiffies, timeout))
 623                         cpu_relax();
 624                 /* start transfer */
 625                 ctrl_outb(1, GDROM_DMA_STATUS_REG);
 626                 wait_event_interruptible_timeout(request_queue,
 627                         gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
 628                 err = gd.transfer ? -EIO : 0;
 629                 gd.transfer = 0;
 630                 gd.pending = 0;
 631                 /* now seek to take the request spinlock
 632                 * before handling ending the request */
 633                 spin_lock(&gdrom_lock);
 634                 list_del_init(&req->queuelist);
 635                 __blk_end_request_all(req, err);
 636         }
 637         spin_unlock(&gdrom_lock);
 638         kfree(read_command);
 639 }
 640
 641 static void gdrom_request(struct request_queue *rq)
 642 {
 643         struct request *req;
 644
 645         while ((req = blk_fetch_request(rq)) != NULL) {
 646                 if (req->cmd_type != REQ_TYPE_FS) {
 647                         printk(KERN_DEBUG "gdrom: Non-fs request ignored\n");
 648                         __blk_end_request_all(req, -EIO);
 649                         continue;
 650                 }
 651                 if (rq_data_dir(req) != READ) {
 652                         pr_notice("Read only device - write request ignored\n");
 653                         __blk_end_request_all(req, -EIO);
 654                         continue;
 655                 }
 656
 657                 /*
 658                  * Add to list of deferred work and then schedule
 659                  * workqueue.
 660                  */
 661                 list_add_tail(&req->queuelist, &gdrom_deferred);
 662                 schedule_work(&work);
 663         }
 664 }
 665
 666 /* Print string identifying GD ROM device */
 667 static int __devinit gdrom_outputversion(void)
 668 {
 669         struct gdrom_id *id;
 670         char *model_name, *manuf_name, *firmw_ver;
 671         int err = -ENOMEM;
 672
 673         /* query device ID */
 674         id = kzalloc(sizeof(struct gdrom_id), GFP_KERNEL);
 675         if (!id)
 676                 return err;
 677         gdrom_identifydevice(id);
 678         model_name = kstrndup(id->modname, 16, GFP_KERNEL);
 679         if (!model_name)
 680                 goto free_id;
 681         manuf_name = kstrndup(id->mname, 16, GFP_KERNEL);
 682         if (!manuf_name)
 683                 goto free_model_name;
 684         firmw_ver = kstrndup(id->firmver, 16, GFP_KERNEL);
 685         if (!firmw_ver)
 686                 goto free_manuf_name;
 687         pr_info("%s from %s with firmware %s\n",
 688                 model_name, manuf_name, firmw_ver);
 689         err = 0;
 690         kfree(firmw_ver);
 691 free_manuf_name:
 692         kfree(manuf_name);
 693 free_model_name:
 694         kfree(model_name);
 695 free_id:
 696         kfree(id);
 697         return err;
 698 }
 699
 700 /* set the default mode for DMA transfer */
 701 static int __devinit gdrom_init_dma_mode(void)
 702 {
 703         ctrl_outb(0x13, GDROM_ERROR_REG);
 704         ctrl_outb(0x22, GDROM_INTSEC_REG);
 705         if (!gdrom_wait_clrbusy())
 706                 return -EBUSY;
 707         ctrl_outb(0xEF, GDROM_STATUSCOMMAND_REG);
 708         if (!gdrom_wait_busy_sleeps())
 709                 return -EBUSY;
 710         /* Memory protection setting for GDROM DMA
 711         * Bits 31 - 16 security: 0x8843
 712         * Bits 15 and 7 reserved (0)
 713         * Bits 14 - 8 start of transfer range in 1 MB blocks OR'ed with 0x80
 714         * Bits 6 - 0 end of transfer range in 1 MB blocks OR'ed with 0x80
 715         * (0x40 | 0x80) = start range at 0x0C000000
 716         * (0x7F | 0x80) = end range at 0x0FFFFFFF */
 717         ctrl_outl(0x8843407F, GDROM_DMA_ACCESS_CTRL_REG);
 718         ctrl_outl(9, GDROM_DMA_WAIT_REG); /* DMA word setting */
 719         return 0;
 720 }
 721
 722 static void __devinit probe_gdrom_setupcd(void)
 723 {
 724         gd.cd_info->ops = &gdrom_ops;
 725         gd.cd_info->capacity = 1;
 726         strcpy(gd.cd_info->name, GDROM_DEV_NAME);
 727         gd.cd_info->mask = CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|
 728                 CDC_SELECT_DISC;
 729 }
 730
 731 static void __devinit probe_gdrom_setupdisk(void)
 732 {
 733         gd.disk->major = gdrom_major;
 734         gd.disk->first_minor = 1;
 735         gd.disk->minors = 1;
 736         strcpy(gd.disk->disk_name, GDROM_DEV_NAME);
 737 }
 738
 739 static int __devinit probe_gdrom_setupqueue(void)
 740 {
 741         blk_queue_logical_block_size(gd.gdrom_rq, GDROM_HARD_SECTOR);
 742         /* using DMA so memory will need to be contiguous */
 743         blk_queue_max_segments(gd.gdrom_rq, 1);
 744         /* set a large max size to get most from DMA */
 745         blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);
 746         gd.disk->queue = gd.gdrom_rq;
 747         return gdrom_init_dma_mode();
 748 }
 749
 750 /*
 751  * register this as a block device and as compliant with the
 752  * universal CD Rom driver interface
 753  */
 754 static int __devinit probe_gdrom(struct platform_device *devptr)
 755 {
 756         int err;
 757         /* Start the device */
 758         if (gdrom_execute_diagnostic() != 1) {
 759                 pr_warning("ATA Probe for GDROM failed\n");
 760                 return -ENODEV;
 761         }
 762         /* Print out firmware ID */
 763         if (gdrom_outputversion())
 764                 return -ENOMEM;
 765         /* Register GDROM */
 766         gdrom_major = register_blkdev(0, GDROM_DEV_NAME);
 767         if (gdrom_major <= 0)
 768                 return gdrom_major;
 769         pr_info("Registered with major number %d\n",
 770                 gdrom_major);
 771         /* Specify basic properties of drive */
 772         gd.cd_info = kzalloc(sizeof(struct cdrom_device_info), GFP_KERNEL);
 773         if (!gd.cd_info) {
 774                 err = -ENOMEM;
 775                 goto probe_fail_no_mem;
 776         }
 777         probe_gdrom_setupcd();
 778         gd.disk = alloc_disk(1);
 779         if (!gd.disk) {
 780                 err = -ENODEV;
 781                 goto probe_fail_no_disk;
 782         }
 783         probe_gdrom_setupdisk();
 784         if (register_cdrom(gd.cd_info)) {
 785                 err = -ENODEV;
 786                 goto probe_fail_cdrom_register;
 787         }
 788         gd.disk->fops = &gdrom_bdops;
 789         /* latch on to the interrupt */
 790         err = gdrom_set_interrupt_handlers();
 791         if (err)
 792                 goto probe_fail_cmdirq_register;
 793         gd.gdrom_rq = blk_init_queue(gdrom_request, &gdrom_lock);
 794         if (!gd.gdrom_rq)
 795                 goto probe_fail_requestq;
 796
 797         err = probe_gdrom_setupqueue();
 798         if (err)
 799                 goto probe_fail_toc;
 800
 801         gd.toc = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
 802         if (!gd.toc)
 803                 goto probe_fail_toc;
 804         add_disk(gd.disk);
 805         return 0;
 806
 807 probe_fail_toc:
 808         blk_cleanup_queue(gd.gdrom_rq);
 809 probe_fail_requestq:
 810         free_irq(HW_EVENT_GDROM_DMA, &gd);
 811         free_irq(HW_EVENT_GDROM_CMD, &gd);
 812 probe_fail_cmdirq_register:
 813 probe_fail_cdrom_register:
 814         del_gendisk(gd.disk);
 815 probe_fail_no_disk:
 816         kfree(gd.cd_info);
 817         unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 818         gdrom_major = 0;
 819 probe_fail_no_mem:
 820         pr_warning("Probe failed - error is 0x%X\n", err);
 821         return err;
 822 }
 823
 824 static int __devexit remove_gdrom(struct platform_device *devptr)
 825 {
 826         flush_scheduled_work();
 827         blk_cleanup_queue(gd.gdrom_rq);
 828         free_irq(HW_EVENT_GDROM_CMD, &gd);
 829         free_irq(HW_EVENT_GDROM_DMA, &gd);
 830         del_gendisk(gd.disk);
 831         if (gdrom_major)
 832                 unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 833         unregister_cdrom(gd.cd_info);
 834
 835         return 0;
 836 }
 837
 838 static struct platform_driver gdrom_driver = {
 839         .probe = probe_gdrom,
 840         .remove = __devexit_p(remove_gdrom),
 841         .driver = {
 842                         .name = GDROM_DEV_NAME,
 843         },
 844 };
 845
 846 static int __init init_gdrom(void)
 847 {
 848         int rc;
 849         gd.toc = NULL;
 850         rc = platform_driver_register(&gdrom_driver);
 851         if (rc)
 852                 return rc;
 853         pd = platform_device_register_simple(GDROM_DEV_NAME, -1, NULL, 0);
 854         if (IS_ERR(pd)) {
 855                 platform_driver_unregister(&gdrom_driver);
 856                 return PTR_ERR(pd);
 857         }
 858         return 0;
 859 }
 860
 861 static void __exit exit_gdrom(void)
 862 {
 863         platform_device_unregister(pd);
 864         platform_driver_unregister(&gdrom_driver);
 865         kfree(gd.toc);
 866 }
 867
 868 module_init(init_gdrom);
 869 module_exit(exit_gdrom);
 870 MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
 871 MODULE_DESCRIPTION("SEGA Dreamcast GD-ROM Driver");
 872 MODULE_LICENSE("GPL");