linux/drivers/cdrom/gdrom.c
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   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/mutex.h>
  38#include <linux/wait.h>
  39#include <linux/workqueue.h>
  40#include <linux/platform_device.h>
  41#include <scsi/scsi.h>
  42#include <asm/io.h>
  43#include <asm/dma.h>
  44#include <asm/delay.h>
  45#include <mach/dma.h>
  46#include <mach/sysasic.h>
  47
  48#define GDROM_DEV_NAME "gdrom"
  49#define GD_SESSION_OFFSET 150
  50
  51/* GD Rom commands */
  52#define GDROM_COM_SOFTRESET 0x08
  53#define GDROM_COM_EXECDIAG 0x90
  54#define GDROM_COM_PACKET 0xA0
  55#define GDROM_COM_IDDEV 0xA1
  56
  57/* GD Rom registers */
  58#define GDROM_BASE_REG                  0xA05F7000
  59#define GDROM_ALTSTATUS_REG             (GDROM_BASE_REG + 0x18)
  60#define GDROM_DATA_REG                  (GDROM_BASE_REG + 0x80)
  61#define GDROM_ERROR_REG         (GDROM_BASE_REG + 0x84)
  62#define GDROM_INTSEC_REG                (GDROM_BASE_REG + 0x88)
  63#define GDROM_SECNUM_REG                (GDROM_BASE_REG + 0x8C)
  64#define GDROM_BCL_REG                   (GDROM_BASE_REG + 0x90)
  65#define GDROM_BCH_REG                   (GDROM_BASE_REG + 0x94)
  66#define GDROM_DSEL_REG                  (GDROM_BASE_REG + 0x98)
  67#define GDROM_STATUSCOMMAND_REG (GDROM_BASE_REG + 0x9C)
  68#define GDROM_RESET_REG         (GDROM_BASE_REG + 0x4E4)
  69
  70#define GDROM_DMA_STARTADDR_REG (GDROM_BASE_REG + 0x404)
  71#define GDROM_DMA_LENGTH_REG            (GDROM_BASE_REG + 0x408)
  72#define GDROM_DMA_DIRECTION_REG (GDROM_BASE_REG + 0x40C)
  73#define GDROM_DMA_ENABLE_REG            (GDROM_BASE_REG + 0x414)
  74#define GDROM_DMA_STATUS_REG            (GDROM_BASE_REG + 0x418)
  75#define GDROM_DMA_WAIT_REG              (GDROM_BASE_REG + 0x4A0)
  76#define GDROM_DMA_ACCESS_CTRL_REG       (GDROM_BASE_REG + 0x4B8)
  77
  78#define GDROM_HARD_SECTOR       2048
  79#define BLOCK_LAYER_SECTOR      512
  80#define GD_TO_BLK               4
  81
  82#define GDROM_DEFAULT_TIMEOUT   (HZ * 7)
  83
  84static DEFINE_MUTEX(gdrom_mutex);
  85static const struct {
  86        int sense_key;
  87        const char * const text;
  88} sense_texts[] = {
  89        {NO_SENSE, "OK"},
  90        {RECOVERED_ERROR, "Recovered from error"},
  91        {NOT_READY, "Device not ready"},
  92        {MEDIUM_ERROR, "Disk not ready"},
  93        {HARDWARE_ERROR, "Hardware error"},
  94        {ILLEGAL_REQUEST, "Command has failed"},
  95        {UNIT_ATTENTION, "Device needs attention - disk may have been changed"},
  96        {DATA_PROTECT, "Data protection error"},
  97        {ABORTED_COMMAND, "Command aborted"},
  98};
  99
 100static struct platform_device *pd;
 101static int gdrom_major;
 102static DECLARE_WAIT_QUEUE_HEAD(command_queue);
 103static DECLARE_WAIT_QUEUE_HEAD(request_queue);
 104
 105static DEFINE_SPINLOCK(gdrom_lock);
 106static void gdrom_readdisk_dma(struct work_struct *work);
 107static DECLARE_WORK(work, gdrom_readdisk_dma);
 108static LIST_HEAD(gdrom_deferred);
 109
 110struct gdromtoc {
 111        unsigned int entry[99];
 112        unsigned int first, last;
 113        unsigned int leadout;
 114};
 115
 116static struct gdrom_unit {
 117        struct gendisk *disk;
 118        struct cdrom_device_info *cd_info;
 119        int status;
 120        int pending;
 121        int transfer;
 122        char disk_type;
 123        struct gdromtoc *toc;
 124        struct request_queue *gdrom_rq;
 125} gd;
 126
 127struct gdrom_id {
 128        char mid;
 129        char modid;
 130        char verid;
 131        char padA[13];
 132        char mname[16];
 133        char modname[16];
 134        char firmver[16];
 135        char padB[16];
 136};
 137
 138static int gdrom_getsense(short *bufstring);
 139static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
 140        struct packet_command *command);
 141static int gdrom_hardreset(struct cdrom_device_info *cd_info);
 142
 143static bool gdrom_is_busy(void)
 144{
 145        return (__raw_readb(GDROM_ALTSTATUS_REG) & 0x80) != 0;
 146}
 147
 148static bool gdrom_data_request(void)
 149{
 150        return (__raw_readb(GDROM_ALTSTATUS_REG) & 0x88) == 8;
 151}
 152
 153static bool gdrom_wait_clrbusy(void)
 154{
 155        unsigned long timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 156        while ((__raw_readb(GDROM_ALTSTATUS_REG) & 0x80) &&
 157                (time_before(jiffies, timeout)))
 158                cpu_relax();
 159        return time_before(jiffies, timeout + 1);
 160}
 161
 162static bool gdrom_wait_busy_sleeps(void)
 163{
 164        unsigned long timeout;
 165        /* Wait to get busy first */
 166        timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 167        while (!gdrom_is_busy() && time_before(jiffies, timeout))
 168                cpu_relax();
 169        /* Now wait for busy to clear */
 170        return gdrom_wait_clrbusy();
 171}
 172
 173static void gdrom_identifydevice(void *buf)
 174{
 175        int c;
 176        short *data = buf;
 177        /* If the device won't clear it has probably
 178        * been hit by a serious failure - but we'll
 179        * try to return a sense key even so */
 180        if (!gdrom_wait_clrbusy()) {
 181                gdrom_getsense(NULL);
 182                return;
 183        }
 184        __raw_writeb(GDROM_COM_IDDEV, GDROM_STATUSCOMMAND_REG);
 185        if (!gdrom_wait_busy_sleeps()) {
 186                gdrom_getsense(NULL);
 187                return;
 188        }
 189        /* now read in the data */
 190        for (c = 0; c < 40; c++)
 191                data[c] = __raw_readw(GDROM_DATA_REG);
 192}
 193
 194static void gdrom_spicommand(void *spi_string, int buflen)
 195{
 196        short *cmd = spi_string;
 197        unsigned long timeout;
 198
 199        /* ensure IRQ_WAIT is set */
 200        __raw_writeb(0x08, GDROM_ALTSTATUS_REG);
 201        /* specify how many bytes we expect back */
 202        __raw_writeb(buflen & 0xFF, GDROM_BCL_REG);
 203        __raw_writeb((buflen >> 8) & 0xFF, GDROM_BCH_REG);
 204        /* other parameters */
 205        __raw_writeb(0, GDROM_INTSEC_REG);
 206        __raw_writeb(0, GDROM_SECNUM_REG);
 207        __raw_writeb(0, GDROM_ERROR_REG);
 208        /* Wait until we can go */
 209        if (!gdrom_wait_clrbusy()) {
 210                gdrom_getsense(NULL);
 211                return;
 212        }
 213        timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 214        __raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
 215        while (!gdrom_data_request() && time_before(jiffies, timeout))
 216                cpu_relax();
 217        if (!time_before(jiffies, timeout + 1)) {
 218                gdrom_getsense(NULL);
 219                return;
 220        }
 221        outsw(GDROM_DATA_REG, cmd, 6);
 222}
 223
 224
 225/* gdrom_command_executediagnostic:
 226 * Used to probe for presence of working GDROM
 227 * Restarts GDROM device and then applies standard ATA 3
 228 * Execute Diagnostic Command: a return of '1' indicates device 0
 229 * present and device 1 absent
 230 */
 231static char gdrom_execute_diagnostic(void)
 232{
 233        gdrom_hardreset(gd.cd_info);
 234        if (!gdrom_wait_clrbusy())
 235                return 0;
 236        __raw_writeb(GDROM_COM_EXECDIAG, GDROM_STATUSCOMMAND_REG);
 237        if (!gdrom_wait_busy_sleeps())
 238                return 0;
 239        return __raw_readb(GDROM_ERROR_REG);
 240}
 241
 242/*
 243 * Prepare disk command
 244 * byte 0 = 0x70
 245 * byte 1 = 0x1f
 246 */
 247static int gdrom_preparedisk_cmd(void)
 248{
 249        struct packet_command *spin_command;
 250        spin_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 251        if (!spin_command)
 252                return -ENOMEM;
 253        spin_command->cmd[0] = 0x70;
 254        spin_command->cmd[2] = 0x1f;
 255        spin_command->buflen = 0;
 256        gd.pending = 1;
 257        gdrom_packetcommand(gd.cd_info, spin_command);
 258        /* 60 second timeout */
 259        wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 260                GDROM_DEFAULT_TIMEOUT);
 261        gd.pending = 0;
 262        kfree(spin_command);
 263        if (gd.status & 0x01) {
 264                /* log an error */
 265                gdrom_getsense(NULL);
 266                return -EIO;
 267        }
 268        return 0;
 269}
 270
 271/*
 272 * Read TOC command
 273 * byte 0 = 0x14
 274 * byte 1 = session
 275 * byte 3 = sizeof TOC >> 8  ie upper byte
 276 * byte 4 = sizeof TOC & 0xff ie lower byte
 277 */
 278static int gdrom_readtoc_cmd(struct gdromtoc *toc, int session)
 279{
 280        int tocsize;
 281        struct packet_command *toc_command;
 282        int err = 0;
 283
 284        toc_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 285        if (!toc_command)
 286                return -ENOMEM;
 287        tocsize = sizeof(struct gdromtoc);
 288        toc_command->cmd[0] = 0x14;
 289        toc_command->cmd[1] = session;
 290        toc_command->cmd[3] = tocsize >> 8;
 291        toc_command->cmd[4] = tocsize & 0xff;
 292        toc_command->buflen = tocsize;
 293        if (gd.pending) {
 294                err = -EBUSY;
 295                goto cleanup_readtoc_final;
 296        }
 297        gd.pending = 1;
 298        gdrom_packetcommand(gd.cd_info, toc_command);
 299        wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 300                GDROM_DEFAULT_TIMEOUT);
 301        if (gd.pending) {
 302                err = -EINVAL;
 303                goto cleanup_readtoc;
 304        }
 305        insw(GDROM_DATA_REG, toc, tocsize/2);
 306        if (gd.status & 0x01)
 307                err = -EINVAL;
 308
 309cleanup_readtoc:
 310        gd.pending = 0;
 311cleanup_readtoc_final:
 312        kfree(toc_command);
 313        return err;
 314}
 315
 316/* TOC helpers */
 317static int get_entry_lba(int track)
 318{
 319        return (cpu_to_be32(track & 0xffffff00) - GD_SESSION_OFFSET);
 320}
 321
 322static int get_entry_q_ctrl(int track)
 323{
 324        return (track & 0x000000f0) >> 4;
 325}
 326
 327static int get_entry_track(int track)
 328{
 329        return (track & 0x0000ff00) >> 8;
 330}
 331
 332static int gdrom_get_last_session(struct cdrom_device_info *cd_info,
 333        struct cdrom_multisession *ms_info)
 334{
 335        int fentry, lentry, track, data, tocuse, err;
 336        if (!gd.toc)
 337                return -ENOMEM;
 338        tocuse = 1;
 339        /* Check if GD-ROM */
 340        err = gdrom_readtoc_cmd(gd.toc, 1);
 341        /* Not a GD-ROM so check if standard CD-ROM */
 342        if (err) {
 343                tocuse = 0;
 344                err = gdrom_readtoc_cmd(gd.toc, 0);
 345                if (err) {
 346                        pr_info("Could not get CD table of contents\n");
 347                        return -ENXIO;
 348                }
 349        }
 350
 351        fentry = get_entry_track(gd.toc->first);
 352        lentry = get_entry_track(gd.toc->last);
 353        /* Find the first data track */
 354        track = get_entry_track(gd.toc->last);
 355        do {
 356                data = gd.toc->entry[track - 1];
 357                if (get_entry_q_ctrl(data))
 358                        break;  /* ie a real data track */
 359                track--;
 360        } while (track >= fentry);
 361
 362        if ((track > 100) || (track < get_entry_track(gd.toc->first))) {
 363                pr_info("No data on the last session of the CD\n");
 364                gdrom_getsense(NULL);
 365                return -ENXIO;
 366        }
 367
 368        ms_info->addr_format = CDROM_LBA;
 369        ms_info->addr.lba = get_entry_lba(data);
 370        ms_info->xa_flag = 1;
 371        return 0;
 372}
 373
 374static int gdrom_open(struct cdrom_device_info *cd_info, int purpose)
 375{
 376        /* spin up the disk */
 377        return gdrom_preparedisk_cmd();
 378}
 379
 380/* this function is required even if empty */
 381static void gdrom_release(struct cdrom_device_info *cd_info)
 382{
 383}
 384
 385static int gdrom_drivestatus(struct cdrom_device_info *cd_info, int ignore)
 386{
 387        /* read the sense key */
 388        char sense = __raw_readb(GDROM_ERROR_REG);
 389        sense &= 0xF0;
 390        if (sense == 0)
 391                return CDS_DISC_OK;
 392        if (sense == 0x20)
 393                return CDS_DRIVE_NOT_READY;
 394        /* default */
 395        return CDS_NO_INFO;
 396}
 397
 398static unsigned int gdrom_check_events(struct cdrom_device_info *cd_info,
 399                                       unsigned int clearing, int ignore)
 400{
 401        /* check the sense key */
 402        return (__raw_readb(GDROM_ERROR_REG) & 0xF0) == 0x60 ?
 403                DISK_EVENT_MEDIA_CHANGE : 0;
 404}
 405
 406/* reset the G1 bus */
 407static int gdrom_hardreset(struct cdrom_device_info *cd_info)
 408{
 409        int count;
 410        __raw_writel(0x1fffff, GDROM_RESET_REG);
 411        for (count = 0xa0000000; count < 0xa0200000; count += 4)
 412                __raw_readl(count);
 413        return 0;
 414}
 415
 416/* keep the function looking like the universal
 417 * CD Rom specification  - returning int */
 418static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
 419        struct packet_command *command)
 420{
 421        gdrom_spicommand(&command->cmd, command->buflen);
 422        return 0;
 423}
 424
 425/* Get Sense SPI command
 426 * From Marcus Comstedt
 427 * cmd = 0x13
 428 * cmd + 4 = length of returned buffer
 429 * Returns 5 16 bit words
 430 */
 431static int gdrom_getsense(short *bufstring)
 432{
 433        struct packet_command *sense_command;
 434        short sense[5];
 435        int sense_key;
 436        int err = -EIO;
 437
 438        sense_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 439        if (!sense_command)
 440                return -ENOMEM;
 441        sense_command->cmd[0] = 0x13;
 442        sense_command->cmd[4] = 10;
 443        sense_command->buflen = 10;
 444        /* even if something is pending try to get
 445        * the sense key if possible */
 446        if (gd.pending && !gdrom_wait_clrbusy()) {
 447                err = -EBUSY;
 448                goto cleanup_sense_final;
 449        }
 450        gd.pending = 1;
 451        gdrom_packetcommand(gd.cd_info, sense_command);
 452        wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 453                GDROM_DEFAULT_TIMEOUT);
 454        if (gd.pending)
 455                goto cleanup_sense;
 456        insw(GDROM_DATA_REG, &sense, sense_command->buflen/2);
 457        if (sense[1] & 40) {
 458                pr_info("Drive not ready - command aborted\n");
 459                goto cleanup_sense;
 460        }
 461        sense_key = sense[1] & 0x0F;
 462        if (sense_key < ARRAY_SIZE(sense_texts))
 463                pr_info("%s\n", sense_texts[sense_key].text);
 464        else
 465                pr_err("Unknown sense key: %d\n", sense_key);
 466        if (bufstring) /* return addional sense data */
 467                memcpy(bufstring, &sense[4], 2);
 468        if (sense_key < 2)
 469                err = 0;
 470
 471cleanup_sense:
 472        gd.pending = 0;
 473cleanup_sense_final:
 474        kfree(sense_command);
 475        return err;
 476}
 477
 478static int gdrom_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
 479                             void *arg)
 480{
 481        return -EINVAL;
 482}
 483
 484static struct cdrom_device_ops gdrom_ops = {
 485        .open                   = gdrom_open,
 486        .release                = gdrom_release,
 487        .drive_status           = gdrom_drivestatus,
 488        .check_events           = gdrom_check_events,
 489        .get_last_session       = gdrom_get_last_session,
 490        .reset                  = gdrom_hardreset,
 491        .audio_ioctl            = gdrom_audio_ioctl,
 492        .capability             = CDC_MULTI_SESSION | CDC_MEDIA_CHANGED |
 493                                  CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R,
 494        .n_minors               = 1,
 495};
 496
 497static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
 498{
 499        int ret;
 500        mutex_lock(&gdrom_mutex);
 501        ret = cdrom_open(gd.cd_info, bdev, mode);
 502        mutex_unlock(&gdrom_mutex);
 503        return ret;
 504}
 505
 506static int gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
 507{
 508        mutex_lock(&gdrom_mutex);
 509        cdrom_release(gd.cd_info, mode);
 510        mutex_unlock(&gdrom_mutex);
 511        return 0;
 512}
 513
 514static unsigned int gdrom_bdops_check_events(struct gendisk *disk,
 515                                             unsigned int clearing)
 516{
 517        return cdrom_check_events(gd.cd_info, clearing);
 518}
 519
 520static int gdrom_bdops_ioctl(struct block_device *bdev, fmode_t mode,
 521        unsigned cmd, unsigned long arg)
 522{
 523        int ret;
 524
 525        mutex_lock(&gdrom_mutex);
 526        ret = cdrom_ioctl(gd.cd_info, bdev, mode, cmd, arg);
 527        mutex_unlock(&gdrom_mutex);
 528
 529        return ret;
 530}
 531
 532static const struct block_device_operations gdrom_bdops = {
 533        .owner                  = THIS_MODULE,
 534        .open                   = gdrom_bdops_open,
 535        .release                = gdrom_bdops_release,
 536        .check_events           = gdrom_bdops_check_events,
 537        .ioctl                  = gdrom_bdops_ioctl,
 538};
 539
 540static irqreturn_t gdrom_command_interrupt(int irq, void *dev_id)
 541{
 542        gd.status = __raw_readb(GDROM_STATUSCOMMAND_REG);
 543        if (gd.pending != 1)
 544                return IRQ_HANDLED;
 545        gd.pending = 0;
 546        wake_up_interruptible(&command_queue);
 547        return IRQ_HANDLED;
 548}
 549
 550static irqreturn_t gdrom_dma_interrupt(int irq, void *dev_id)
 551{
 552        gd.status = __raw_readb(GDROM_STATUSCOMMAND_REG);
 553        if (gd.transfer != 1)
 554                return IRQ_HANDLED;
 555        gd.transfer = 0;
 556        wake_up_interruptible(&request_queue);
 557        return IRQ_HANDLED;
 558}
 559
 560static int __devinit gdrom_set_interrupt_handlers(void)
 561{
 562        int err;
 563
 564        err = request_irq(HW_EVENT_GDROM_CMD, gdrom_command_interrupt,
 565                IRQF_DISABLED, "gdrom_command", &gd);
 566        if (err)
 567                return err;
 568        err = request_irq(HW_EVENT_GDROM_DMA, gdrom_dma_interrupt,
 569                IRQF_DISABLED, "gdrom_dma", &gd);
 570        if (err)
 571                free_irq(HW_EVENT_GDROM_CMD, &gd);
 572        return err;
 573}
 574
 575/* Implement DMA read using SPI command
 576 * 0 -> 0x30
 577 * 1 -> mode
 578 * 2 -> block >> 16
 579 * 3 -> block >> 8
 580 * 4 -> block
 581 * 8 -> sectors >> 16
 582 * 9 -> sectors >> 8
 583 * 10 -> sectors
 584 */
 585static void gdrom_readdisk_dma(struct work_struct *work)
 586{
 587        int err, block, block_cnt;
 588        struct packet_command *read_command;
 589        struct list_head *elem, *next;
 590        struct request *req;
 591        unsigned long timeout;
 592
 593        if (list_empty(&gdrom_deferred))
 594                return;
 595        read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 596        if (!read_command)
 597                return; /* get more memory later? */
 598        read_command->cmd[0] = 0x30;
 599        read_command->cmd[1] = 0x20;
 600        spin_lock(&gdrom_lock);
 601        list_for_each_safe(elem, next, &gdrom_deferred) {
 602                req = list_entry(elem, struct request, queuelist);
 603                spin_unlock(&gdrom_lock);
 604                block = blk_rq_pos(req)/GD_TO_BLK + GD_SESSION_OFFSET;
 605                block_cnt = blk_rq_sectors(req)/GD_TO_BLK;
 606                __raw_writel(virt_to_phys(req->buffer), GDROM_DMA_STARTADDR_REG);
 607                __raw_writel(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);
 608                __raw_writel(1, GDROM_DMA_DIRECTION_REG);
 609                __raw_writel(1, GDROM_DMA_ENABLE_REG);
 610                read_command->cmd[2] = (block >> 16) & 0xFF;
 611                read_command->cmd[3] = (block >> 8) & 0xFF;
 612                read_command->cmd[4] = block & 0xFF;
 613                read_command->cmd[8] = (block_cnt >> 16) & 0xFF;
 614                read_command->cmd[9] = (block_cnt >> 8) & 0xFF;
 615                read_command->cmd[10] = block_cnt & 0xFF;
 616                /* set for DMA */
 617                __raw_writeb(1, GDROM_ERROR_REG);
 618                /* other registers */
 619                __raw_writeb(0, GDROM_SECNUM_REG);
 620                __raw_writeb(0, GDROM_BCL_REG);
 621                __raw_writeb(0, GDROM_BCH_REG);
 622                __raw_writeb(0, GDROM_DSEL_REG);
 623                __raw_writeb(0, GDROM_INTSEC_REG);
 624                /* Wait for registers to reset after any previous activity */
 625                timeout = jiffies + HZ / 2;
 626                while (gdrom_is_busy() && time_before(jiffies, timeout))
 627                        cpu_relax();
 628                __raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
 629                timeout = jiffies + HZ / 2;
 630                /* Wait for packet command to finish */
 631                while (gdrom_is_busy() && time_before(jiffies, timeout))
 632                        cpu_relax();
 633                gd.pending = 1;
 634                gd.transfer = 1;
 635                outsw(GDROM_DATA_REG, &read_command->cmd, 6);
 636                timeout = jiffies + HZ / 2;
 637                /* Wait for any pending DMA to finish */
 638                while (__raw_readb(GDROM_DMA_STATUS_REG) &&
 639                        time_before(jiffies, timeout))
 640                        cpu_relax();
 641                /* start transfer */
 642                __raw_writeb(1, GDROM_DMA_STATUS_REG);
 643                wait_event_interruptible_timeout(request_queue,
 644                        gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
 645                err = gd.transfer ? -EIO : 0;
 646                gd.transfer = 0;
 647                gd.pending = 0;
 648                /* now seek to take the request spinlock
 649                * before handling ending the request */
 650                spin_lock(&gdrom_lock);
 651                list_del_init(&req->queuelist);
 652                __blk_end_request_all(req, err);
 653        }
 654        spin_unlock(&gdrom_lock);
 655        kfree(read_command);
 656}
 657
 658static void gdrom_request(struct request_queue *rq)
 659{
 660        struct request *req;
 661
 662        while ((req = blk_fetch_request(rq)) != NULL) {
 663                if (req->cmd_type != REQ_TYPE_FS) {
 664                        printk(KERN_DEBUG "gdrom: Non-fs request ignored\n");
 665                        __blk_end_request_all(req, -EIO);
 666                        continue;
 667                }
 668                if (rq_data_dir(req) != READ) {
 669                        pr_notice("Read only device - write request ignored\n");
 670                        __blk_end_request_all(req, -EIO);
 671                        continue;
 672                }
 673
 674                /*
 675                 * Add to list of deferred work and then schedule
 676                 * workqueue.
 677                 */
 678                list_add_tail(&req->queuelist, &gdrom_deferred);
 679                schedule_work(&work);
 680        }
 681}
 682
 683/* Print string identifying GD ROM device */
 684static int __devinit gdrom_outputversion(void)
 685{
 686        struct gdrom_id *id;
 687        char *model_name, *manuf_name, *firmw_ver;
 688        int err = -ENOMEM;
 689
 690        /* query device ID */
 691        id = kzalloc(sizeof(struct gdrom_id), GFP_KERNEL);
 692        if (!id)
 693                return err;
 694        gdrom_identifydevice(id);
 695        model_name = kstrndup(id->modname, 16, GFP_KERNEL);
 696        if (!model_name)
 697                goto free_id;
 698        manuf_name = kstrndup(id->mname, 16, GFP_KERNEL);
 699        if (!manuf_name)
 700                goto free_model_name;
 701        firmw_ver = kstrndup(id->firmver, 16, GFP_KERNEL);
 702        if (!firmw_ver)
 703                goto free_manuf_name;
 704        pr_info("%s from %s with firmware %s\n",
 705                model_name, manuf_name, firmw_ver);
 706        err = 0;
 707        kfree(firmw_ver);
 708free_manuf_name:
 709        kfree(manuf_name);
 710free_model_name:
 711        kfree(model_name);
 712free_id:
 713        kfree(id);
 714        return err;
 715}
 716
 717/* set the default mode for DMA transfer */
 718static int __devinit gdrom_init_dma_mode(void)
 719{
 720        __raw_writeb(0x13, GDROM_ERROR_REG);
 721        __raw_writeb(0x22, GDROM_INTSEC_REG);
 722        if (!gdrom_wait_clrbusy())
 723                return -EBUSY;
 724        __raw_writeb(0xEF, GDROM_STATUSCOMMAND_REG);
 725        if (!gdrom_wait_busy_sleeps())
 726                return -EBUSY;
 727        /* Memory protection setting for GDROM DMA
 728        * Bits 31 - 16 security: 0x8843
 729        * Bits 15 and 7 reserved (0)
 730        * Bits 14 - 8 start of transfer range in 1 MB blocks OR'ed with 0x80
 731        * Bits 6 - 0 end of transfer range in 1 MB blocks OR'ed with 0x80
 732        * (0x40 | 0x80) = start range at 0x0C000000
 733        * (0x7F | 0x80) = end range at 0x0FFFFFFF */
 734        __raw_writel(0x8843407F, GDROM_DMA_ACCESS_CTRL_REG);
 735        __raw_writel(9, GDROM_DMA_WAIT_REG); /* DMA word setting */
 736        return 0;
 737}
 738
 739static void __devinit probe_gdrom_setupcd(void)
 740{
 741        gd.cd_info->ops = &gdrom_ops;
 742        gd.cd_info->capacity = 1;
 743        strcpy(gd.cd_info->name, GDROM_DEV_NAME);
 744        gd.cd_info->mask = CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|
 745                CDC_SELECT_DISC;
 746}
 747
 748static void __devinit probe_gdrom_setupdisk(void)
 749{
 750        gd.disk->major = gdrom_major;
 751        gd.disk->first_minor = 1;
 752        gd.disk->minors = 1;
 753        strcpy(gd.disk->disk_name, GDROM_DEV_NAME);
 754}
 755
 756static int __devinit probe_gdrom_setupqueue(void)
 757{
 758        blk_queue_logical_block_size(gd.gdrom_rq, GDROM_HARD_SECTOR);
 759        /* using DMA so memory will need to be contiguous */
 760        blk_queue_max_segments(gd.gdrom_rq, 1);
 761        /* set a large max size to get most from DMA */
 762        blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);
 763        gd.disk->queue = gd.gdrom_rq;
 764        return gdrom_init_dma_mode();
 765}
 766
 767/*
 768 * register this as a block device and as compliant with the
 769 * universal CD Rom driver interface
 770 */
 771static int __devinit probe_gdrom(struct platform_device *devptr)
 772{
 773        int err;
 774        /* Start the device */
 775        if (gdrom_execute_diagnostic() != 1) {
 776                pr_warning("ATA Probe for GDROM failed\n");
 777                return -ENODEV;
 778        }
 779        /* Print out firmware ID */
 780        if (gdrom_outputversion())
 781                return -ENOMEM;
 782        /* Register GDROM */
 783        gdrom_major = register_blkdev(0, GDROM_DEV_NAME);
 784        if (gdrom_major <= 0)
 785                return gdrom_major;
 786        pr_info("Registered with major number %d\n",
 787                gdrom_major);
 788        /* Specify basic properties of drive */
 789        gd.cd_info = kzalloc(sizeof(struct cdrom_device_info), GFP_KERNEL);
 790        if (!gd.cd_info) {
 791                err = -ENOMEM;
 792                goto probe_fail_no_mem;
 793        }
 794        probe_gdrom_setupcd();
 795        gd.disk = alloc_disk(1);
 796        if (!gd.disk) {
 797                err = -ENODEV;
 798                goto probe_fail_no_disk;
 799        }
 800        probe_gdrom_setupdisk();
 801        if (register_cdrom(gd.cd_info)) {
 802                err = -ENODEV;
 803                goto probe_fail_cdrom_register;
 804        }
 805        gd.disk->fops = &gdrom_bdops;
 806        /* latch on to the interrupt */
 807        err = gdrom_set_interrupt_handlers();
 808        if (err)
 809                goto probe_fail_cmdirq_register;
 810        gd.gdrom_rq = blk_init_queue(gdrom_request, &gdrom_lock);
 811        if (!gd.gdrom_rq)
 812                goto probe_fail_requestq;
 813
 814        err = probe_gdrom_setupqueue();
 815        if (err)
 816                goto probe_fail_toc;
 817
 818        gd.toc = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
 819        if (!gd.toc)
 820                goto probe_fail_toc;
 821        add_disk(gd.disk);
 822        return 0;
 823
 824probe_fail_toc:
 825        blk_cleanup_queue(gd.gdrom_rq);
 826probe_fail_requestq:
 827        free_irq(HW_EVENT_GDROM_DMA, &gd);
 828        free_irq(HW_EVENT_GDROM_CMD, &gd);
 829probe_fail_cmdirq_register:
 830probe_fail_cdrom_register:
 831        del_gendisk(gd.disk);
 832probe_fail_no_disk:
 833        kfree(gd.cd_info);
 834        unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 835        gdrom_major = 0;
 836probe_fail_no_mem:
 837        pr_warning("Probe failed - error is 0x%X\n", err);
 838        return err;
 839}
 840
 841static int __devexit remove_gdrom(struct platform_device *devptr)
 842{
 843        flush_work_sync(&work);
 844        blk_cleanup_queue(gd.gdrom_rq);
 845        free_irq(HW_EVENT_GDROM_CMD, &gd);
 846        free_irq(HW_EVENT_GDROM_DMA, &gd);
 847        del_gendisk(gd.disk);
 848        if (gdrom_major)
 849                unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 850        unregister_cdrom(gd.cd_info);
 851
 852        return 0;
 853}
 854
 855static struct platform_driver gdrom_driver = {
 856        .probe = probe_gdrom,
 857        .remove = __devexit_p(remove_gdrom),
 858        .driver = {
 859                        .name = GDROM_DEV_NAME,
 860        },
 861};
 862
 863static int __init init_gdrom(void)
 864{
 865        int rc;
 866        gd.toc = NULL;
 867        rc = platform_driver_register(&gdrom_driver);
 868        if (rc)
 869                return rc;
 870        pd = platform_device_register_simple(GDROM_DEV_NAME, -1, NULL, 0);
 871        if (IS_ERR(pd)) {
 872                platform_driver_unregister(&gdrom_driver);
 873                return PTR_ERR(pd);
 874        }
 875        return 0;
 876}
 877
 878static void __exit exit_gdrom(void)
 879{
 880        platform_device_unregister(pd);
 881        platform_driver_unregister(&gdrom_driver);
 882        kfree(gd.toc);
 883}
 884
 885module_init(init_gdrom);
 886module_exit(exit_gdrom);
 887MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
 888MODULE_DESCRIPTION("SEGA Dreamcast GD-ROM Driver");
 889MODULE_LICENSE("GPL");
 890