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#include <linux/init.h>
  23#include <linux/module.h>
  24#include <linux/fs.h>
  25#include <linux/kernel.h>
  26#include <linux/list.h>
  27#include <linux/slab.h>
  28#include <linux/dma-mapping.h>
  29#include <linux/cdrom.h>
  30#include <linux/genhd.h>
  31#include <linux/bio.h>
  32#include <linux/blkdev.h>
  33#include <linux/interrupt.h>
  34#include <linux/device.h>
  35#include <linux/wait.h>
  36#include <linux/workqueue.h>
  37#include <linux/platform_device.h>
  38#include <scsi/scsi.h>
  39#include <asm/io.h>
  40#include <asm/dma.h>
  41#include <asm/delay.h>
  42#include <mach/dma.h>
  43#include <mach/sysasic.h>
  44
  45#define GDROM_DEV_NAME "gdrom"
  46#define GD_SESSION_OFFSET 150
  47
  48/* GD Rom commands */
  49#define GDROM_COM_SOFTRESET 0x08
  50#define GDROM_COM_EXECDIAG 0x90
  51#define GDROM_COM_PACKET 0xA0
  52#define GDROM_COM_IDDEV 0xA1
  53
  54/* GD Rom registers */
  55#define GDROM_BASE_REG                  0xA05F7000
  56#define GDROM_ALTSTATUS_REG             (GDROM_BASE_REG + 0x18)
  57#define GDROM_DATA_REG                  (GDROM_BASE_REG + 0x80)
  58#define GDROM_ERROR_REG         (GDROM_BASE_REG + 0x84)
  59#define GDROM_INTSEC_REG                (GDROM_BASE_REG + 0x88)
  60#define GDROM_SECNUM_REG                (GDROM_BASE_REG + 0x8C)
  61#define GDROM_BCL_REG                   (GDROM_BASE_REG + 0x90)
  62#define GDROM_BCH_REG                   (GDROM_BASE_REG + 0x94)
  63#define GDROM_DSEL_REG                  (GDROM_BASE_REG + 0x98)
  64#define GDROM_STATUSCOMMAND_REG (GDROM_BASE_REG + 0x9C)
  65#define GDROM_RESET_REG         (GDROM_BASE_REG + 0x4E4)
  66
  67#define GDROM_DMA_STARTADDR_REG (GDROM_BASE_REG + 0x404)
  68#define GDROM_DMA_LENGTH_REG            (GDROM_BASE_REG + 0x408)
  69#define GDROM_DMA_DIRECTION_REG (GDROM_BASE_REG + 0x40C)
  70#define GDROM_DMA_ENABLE_REG            (GDROM_BASE_REG + 0x414)
  71#define GDROM_DMA_STATUS_REG            (GDROM_BASE_REG + 0x418)
  72#define GDROM_DMA_WAIT_REG              (GDROM_BASE_REG + 0x4A0)
  73#define GDROM_DMA_ACCESS_CTRL_REG       (GDROM_BASE_REG + 0x4B8)
  74
  75#define GDROM_HARD_SECTOR       2048
  76#define BLOCK_LAYER_SECTOR      512
  77#define GD_TO_BLK               4
  78
  79#define GDROM_DEFAULT_TIMEOUT   (HZ * 7)
  80
  81static const struct {
  82        int sense_key;
  83        const char * const text;
  84} sense_texts[] = {
  85        {NO_SENSE, "OK"},
  86        {RECOVERED_ERROR, "Recovered from error"},
  87        {NOT_READY, "Device not ready"},
  88        {MEDIUM_ERROR, "Disk not ready"},
  89        {HARDWARE_ERROR, "Hardware error"},
  90        {ILLEGAL_REQUEST, "Command has failed"},
  91        {UNIT_ATTENTION, "Device needs attention - disk may have been changed"},
  92        {DATA_PROTECT, "Data protection error"},
  93        {ABORTED_COMMAND, "Command aborted"},
  94};
  95
  96static struct platform_device *pd;
  97static int gdrom_major;
  98static DECLARE_WAIT_QUEUE_HEAD(command_queue);
  99static DECLARE_WAIT_QUEUE_HEAD(request_queue);
 100
 101static DEFINE_SPINLOCK(gdrom_lock);
 102static void gdrom_readdisk_dma(struct work_struct *work);
 103static DECLARE_WORK(work, gdrom_readdisk_dma);
 104static LIST_HEAD(gdrom_deferred);
 105
 106struct gdromtoc {
 107        unsigned int entry[99];
 108        unsigned int first, last;
 109        unsigned int leadout;
 110};
 111
 112static struct gdrom_unit {
 113        struct gendisk *disk;
 114        struct cdrom_device_info *cd_info;
 115        int status;
 116        int pending;
 117        int transfer;
 118        char disk_type;
 119        struct gdromtoc *toc;
 120        struct request_queue *gdrom_rq;
 121} gd;
 122
 123struct gdrom_id {
 124        char mid;
 125        char modid;
 126        char verid;
 127        char padA[13];
 128        char mname[16];
 129        char modname[16];
 130        char firmver[16];
 131        char padB[16];
 132};
 133
 134static int gdrom_getsense(short *bufstring);
 135static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
 136        struct packet_command *command);
 137static int gdrom_hardreset(struct cdrom_device_info *cd_info);
 138
 139static bool gdrom_is_busy(void)
 140{
 141        return (ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) != 0;
 142}
 143
 144static bool gdrom_data_request(void)
 145{
 146        return (ctrl_inb(GDROM_ALTSTATUS_REG) & 0x88) == 8;
 147}
 148
 149static bool gdrom_wait_clrbusy(void)
 150{
 151        unsigned long timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 152        while ((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) &&
 153                (time_before(jiffies, timeout)))
 154                cpu_relax();
 155        return time_before(jiffies, timeout + 1);
 156}
 157
 158static bool gdrom_wait_busy_sleeps(void)
 159{
 160        unsigned long timeout;
 161        /* Wait to get busy first */
 162        timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 163        while (!gdrom_is_busy() && time_before(jiffies, timeout))
 164                cpu_relax();
 165        /* Now wait for busy to clear */
 166        return gdrom_wait_clrbusy();
 167}
 168
 169static void gdrom_identifydevice(void *buf)
 170{
 171        int c;
 172        short *data = buf;
 173        /* If the device won't clear it has probably
 174        * been hit by a serious failure - but we'll
 175        * try to return a sense key even so */
 176        if (!gdrom_wait_clrbusy()) {
 177                gdrom_getsense(NULL);
 178                return;
 179        }
 180        ctrl_outb(GDROM_COM_IDDEV, GDROM_STATUSCOMMAND_REG);
 181        if (!gdrom_wait_busy_sleeps()) {
 182                gdrom_getsense(NULL);
 183                return;
 184        }
 185        /* now read in the data */
 186        for (c = 0; c < 40; c++)
 187                data[c] = ctrl_inw(GDROM_DATA_REG);
 188}
 189
 190static void gdrom_spicommand(void *spi_string, int buflen)
 191{
 192        short *cmd = spi_string;
 193        unsigned long timeout;
 194
 195        /* ensure IRQ_WAIT is set */
 196        ctrl_outb(0x08, GDROM_ALTSTATUS_REG);
 197        /* specify how many bytes we expect back */
 198        ctrl_outb(buflen & 0xFF, GDROM_BCL_REG);
 199        ctrl_outb((buflen >> 8) & 0xFF, GDROM_BCH_REG);
 200        /* other parameters */
 201        ctrl_outb(0, GDROM_INTSEC_REG);
 202        ctrl_outb(0, GDROM_SECNUM_REG);
 203        ctrl_outb(0, GDROM_ERROR_REG);
 204        /* Wait until we can go */
 205        if (!gdrom_wait_clrbusy()) {
 206                gdrom_getsense(NULL);
 207                return;
 208        }
 209        timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
 210        ctrl_outb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
 211        while (!gdrom_data_request() && time_before(jiffies, timeout))
 212                cpu_relax();
 213        if (!time_before(jiffies, timeout + 1)) {
 214                gdrom_getsense(NULL);
 215                return;
 216        }
 217        outsw(PHYSADDR(GDROM_DATA_REG), cmd, 6);
 218}
 219
 220
 221/* gdrom_command_executediagnostic:
 222 * Used to probe for presence of working GDROM
 223 * Restarts GDROM device and then applies standard ATA 3
 224 * Execute Diagnostic Command: a return of '1' indicates device 0
 225 * present and device 1 absent
 226 */
 227static char gdrom_execute_diagnostic(void)
 228{
 229        gdrom_hardreset(gd.cd_info);
 230        if (!gdrom_wait_clrbusy())
 231                return 0;
 232        ctrl_outb(GDROM_COM_EXECDIAG, GDROM_STATUSCOMMAND_REG);
 233        if (!gdrom_wait_busy_sleeps())
 234                return 0;
 235        return ctrl_inb(GDROM_ERROR_REG);
 236}
 237
 238/*
 239 * Prepare disk command
 240 * byte 0 = 0x70
 241 * byte 1 = 0x1f
 242 */
 243static int gdrom_preparedisk_cmd(void)
 244{
 245        struct packet_command *spin_command;
 246        spin_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 247        if (!spin_command)
 248                return -ENOMEM;
 249        spin_command->cmd[0] = 0x70;
 250        spin_command->cmd[2] = 0x1f;
 251        spin_command->buflen = 0;
 252        gd.pending = 1;
 253        gdrom_packetcommand(gd.cd_info, spin_command);
 254        /* 60 second timeout */
 255        wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 256                GDROM_DEFAULT_TIMEOUT);
 257        gd.pending = 0;
 258        kfree(spin_command);
 259        if (gd.status & 0x01) {
 260                /* log an error */
 261                gdrom_getsense(NULL);
 262                return -EIO;
 263        }
 264        return 0;
 265}
 266
 267/*
 268 * Read TOC command
 269 * byte 0 = 0x14
 270 * byte 1 = session
 271 * byte 3 = sizeof TOC >> 8  ie upper byte
 272 * byte 4 = sizeof TOC & 0xff ie lower byte
 273 */
 274static int gdrom_readtoc_cmd(struct gdromtoc *toc, int session)
 275{
 276        int tocsize;
 277        struct packet_command *toc_command;
 278        int err = 0;
 279
 280        toc_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
 281        if (!toc_command)
 282                return -ENOMEM;
 283        tocsize = sizeof(struct gdromtoc);
 284        toc_command->cmd[0] = 0x14;
 285        toc_command->cmd[1] = session;
 286        toc_command->cmd[3] = tocsize >> 8;
 287        toc_command->cmd[4] = tocsize & 0xff;
 288        toc_command->buflen = tocsize;
 289        if (gd.pending) {
 290                err = -EBUSY;
 291                goto cleanup_readtoc_final;
 292        }
 293        gd.pending = 1;
 294        gdrom_packetcommand(gd.cd_info, toc_command);
 295        wait_event_interruptible_timeout(command_queue, gd.pending == 0,
 296                GDROM_DEFAULT_TIMEOUT);
 297        if (gd.pending) {
 298                err = -EINVAL;
 299                goto cleanup_readtoc;
 300        }
 301        insw(PHYSADDR(GDROM_DATA_REG), toc, tocsize/2);
 302        if (gd.status & 0x01)
 303                err = -EINVAL;
 304
 305cleanup_readtoc:
 306        gd.pending = 0;
 307cleanup_readtoc_final:
 308        kfree(toc_command);
 309        return err;
 310}
 311
 312/* TOC helpers */
 313static int get_entry_lba(int track)
 314{
 315        return (cpu_to_be32(track & 0xffffff00) - GD_SESSION_OFFSET);
 316}
 317
 318static int get_entry_q_ctrl(int track)
 319{
 320        return (track & 0x000000f0) >> 4;
 321}
 322
 323static int get_entry_track(int track)
 324{
 325        return (track & 0x0000ff00) >> 8;
 326}
 327
 328static int gdrom_get_last_session(struct cdrom_device_info *cd_info,
 329        struct cdrom_multisession *ms_info)
 330{
 331        int fentry, lentry, track, data, tocuse, err;
 332        if (!gd.toc)
 333                return -ENOMEM;
 334        tocuse = 1;
 335        /* Check if GD-ROM */
 336        err = gdrom_readtoc_cmd(gd.toc, 1);
 337        /* Not a GD-ROM so check if standard CD-ROM */
 338        if (err) {
 339                tocuse = 0;
 340                err = gdrom_readtoc_cmd(gd.toc, 0);
 341                if (err) {
 342                        printk(KERN_INFO "GDROM: Could not get CD "
 343                                "table of contents\n");
 344                        return -ENXIO;
 345                }
 346        }
 347
 348        fentry = get_entry_track(gd.toc->first);
 349        lentry = get_entry_track(gd.toc->last);
 350        /* Find the first data track */
 351        track = get_entry_track(gd.toc->last);
 352        do {
 353                data = gd.toc->entry[track - 1];
 354                if (get_entry_q_ctrl(data))
 355                        break;  /* ie a real data track */
 356                track--;
 357        } while (track >= fentry);
 358
 359        if ((track > 100) || (track < get_entry_track(gd.toc->first))) {
 360                printk(KERN_INFO "GDROM: No data on the last "
 361                        "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
 372static 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 */
 379static void gdrom_release(struct cdrom_device_info *cd_info)
 380{
 381}
 382
 383static 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
 396static 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 */
 403static 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 */
 414static 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 */
 427static 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(PHYSADDR(GDROM_DATA_REG), &sense, sense_command->buflen/2);
 453        if (sense[1] & 40) {
 454                printk(KERN_INFO "GDROM: 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                printk(KERN_INFO "GDROM: %s\n", sense_texts[sense_key].text);
 460        else
 461                printk(KERN_ERR "GDROM: 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
 467cleanup_sense:
 468        gd.pending = 0;
 469cleanup_sense_final:
 470        kfree(sense_command);
 471        return err;
 472}
 473
 474static int gdrom_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
 475                             void *arg)
 476{
 477        return -EINVAL;
 478}
 479
 480static 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
 493static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
 494{
 495        return cdrom_open(gd.cd_info, bdev, mode);
 496}
 497
 498static int gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
 499{
 500        cdrom_release(gd.cd_info, mode);
 501        return 0;
 502}
 503
 504static int gdrom_bdops_mediachanged(struct gendisk *disk)
 505{
 506        return cdrom_media_changed(gd.cd_info);
 507}
 508
 509static 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
 515static 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
 523static 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
 533static 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
 543static 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 */
 568static 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 = req->sector/GD_TO_BLK + GD_SESSION_OFFSET;
 588                block_cnt = req->nr_sectors/GD_TO_BLK;
 589                ctrl_outl(PHYSADDR(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(PHYSADDR(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(req, err, blk_rq_bytes(req));
 636        }
 637        spin_unlock(&gdrom_lock);
 638        kfree(read_command);
 639}
 640
 641static void gdrom_request_handler_dma(struct request *req)
 642{
 643        /* dequeue, add to list of deferred work
 644        * and then schedule workqueue */
 645        blkdev_dequeue_request(req);
 646        list_add_tail(&req->queuelist, &gdrom_deferred);
 647        schedule_work(&work);
 648}
 649
 650static void gdrom_request(struct request_queue *rq)
 651{
 652        struct request *req;
 653
 654        while ((req = elv_next_request(rq)) != NULL) {
 655                if (!blk_fs_request(req)) {
 656                        printk(KERN_DEBUG "GDROM: Non-fs request ignored\n");
 657                        end_request(req, 0);
 658                }
 659                if (rq_data_dir(req) != READ) {
 660                        printk(KERN_NOTICE "GDROM: Read only device -");
 661                        printk(" write request ignored\n");
 662                        end_request(req, 0);
 663                }
 664                if (req->nr_sectors)
 665                        gdrom_request_handler_dma(req);
 666                else
 667                        end_request(req, 0);
 668        }
 669}
 670
 671/* Print string identifying GD ROM device */
 672static int __devinit gdrom_outputversion(void)
 673{
 674        struct gdrom_id *id;
 675        char *model_name, *manuf_name, *firmw_ver;
 676        int err = -ENOMEM;
 677
 678        /* query device ID */
 679        id = kzalloc(sizeof(struct gdrom_id), GFP_KERNEL);
 680        if (!id)
 681                return err;
 682        gdrom_identifydevice(id);
 683        model_name = kstrndup(id->modname, 16, GFP_KERNEL);
 684        if (!model_name)
 685                goto free_id;
 686        manuf_name = kstrndup(id->mname, 16, GFP_KERNEL);
 687        if (!manuf_name)
 688                goto free_model_name;
 689        firmw_ver = kstrndup(id->firmver, 16, GFP_KERNEL);
 690        if (!firmw_ver)
 691                goto free_manuf_name;
 692        printk(KERN_INFO "GDROM: %s from %s with firmware %s\n",
 693                model_name, manuf_name, firmw_ver);
 694        err = 0;
 695        kfree(firmw_ver);
 696free_manuf_name:
 697        kfree(manuf_name);
 698free_model_name:
 699        kfree(model_name);
 700free_id:
 701        kfree(id);
 702        return err;
 703}
 704
 705/* set the default mode for DMA transfer */
 706static int __devinit gdrom_init_dma_mode(void)
 707{
 708        ctrl_outb(0x13, GDROM_ERROR_REG);
 709        ctrl_outb(0x22, GDROM_INTSEC_REG);
 710        if (!gdrom_wait_clrbusy())
 711                return -EBUSY;
 712        ctrl_outb(0xEF, GDROM_STATUSCOMMAND_REG);
 713        if (!gdrom_wait_busy_sleeps())
 714                return -EBUSY;
 715        /* Memory protection setting for GDROM DMA
 716        * Bits 31 - 16 security: 0x8843
 717        * Bits 15 and 7 reserved (0)
 718        * Bits 14 - 8 start of transfer range in 1 MB blocks OR'ed with 0x80
 719        * Bits 6 - 0 end of transfer range in 1 MB blocks OR'ed with 0x80
 720        * (0x40 | 0x80) = start range at 0x0C000000
 721        * (0x7F | 0x80) = end range at 0x0FFFFFFF */
 722        ctrl_outl(0x8843407F, GDROM_DMA_ACCESS_CTRL_REG);
 723        ctrl_outl(9, GDROM_DMA_WAIT_REG); /* DMA word setting */
 724        return 0;
 725}
 726
 727static void __devinit probe_gdrom_setupcd(void)
 728{
 729        gd.cd_info->ops = &gdrom_ops;
 730        gd.cd_info->capacity = 1;
 731        strcpy(gd.cd_info->name, GDROM_DEV_NAME);
 732        gd.cd_info->mask = CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|
 733                CDC_SELECT_DISC;
 734}
 735
 736static void __devinit probe_gdrom_setupdisk(void)
 737{
 738        gd.disk->major = gdrom_major;
 739        gd.disk->first_minor = 1;
 740        gd.disk->minors = 1;
 741        strcpy(gd.disk->disk_name, GDROM_DEV_NAME);
 742}
 743
 744static int __devinit probe_gdrom_setupqueue(void)
 745{
 746        blk_queue_hardsect_size(gd.gdrom_rq, GDROM_HARD_SECTOR);
 747        /* using DMA so memory will need to be contiguous */
 748        blk_queue_max_hw_segments(gd.gdrom_rq, 1);
 749        /* set a large max size to get most from DMA */
 750        blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);
 751        gd.disk->queue = gd.gdrom_rq;
 752        return gdrom_init_dma_mode();
 753}
 754
 755/*
 756 * register this as a block device and as compliant with the
 757 * universal CD Rom driver interface
 758 */
 759static int __devinit probe_gdrom(struct platform_device *devptr)
 760{
 761        int err;
 762        /* Start the device */
 763        if (gdrom_execute_diagnostic() != 1) {
 764                printk(KERN_WARNING "GDROM: ATA Probe for GDROM failed.\n");
 765                return -ENODEV;
 766        }
 767        /* Print out firmware ID */
 768        if (gdrom_outputversion())
 769                return -ENOMEM;
 770        /* Register GDROM */
 771        gdrom_major = register_blkdev(0, GDROM_DEV_NAME);
 772        if (gdrom_major <= 0)
 773                return gdrom_major;
 774        printk(KERN_INFO "GDROM: Registered with major number %d\n",
 775                gdrom_major);
 776        /* Specify basic properties of drive */
 777        gd.cd_info = kzalloc(sizeof(struct cdrom_device_info), GFP_KERNEL);
 778        if (!gd.cd_info) {
 779                err = -ENOMEM;
 780                goto probe_fail_no_mem;
 781        }
 782        probe_gdrom_setupcd();
 783        gd.disk = alloc_disk(1);
 784        if (!gd.disk) {
 785                err = -ENODEV;
 786                goto probe_fail_no_disk;
 787        }
 788        probe_gdrom_setupdisk();
 789        if (register_cdrom(gd.cd_info)) {
 790                err = -ENODEV;
 791                goto probe_fail_cdrom_register;
 792        }
 793        gd.disk->fops = &gdrom_bdops;
 794        /* latch on to the interrupt */
 795        err = gdrom_set_interrupt_handlers();
 796        if (err)
 797                goto probe_fail_cmdirq_register;
 798        gd.gdrom_rq = blk_init_queue(gdrom_request, &gdrom_lock);
 799        if (!gd.gdrom_rq)
 800                goto probe_fail_requestq;
 801
 802        err = probe_gdrom_setupqueue();
 803        if (err)
 804                goto probe_fail_toc;
 805
 806        gd.toc = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
 807        if (!gd.toc)
 808                goto probe_fail_toc;
 809        add_disk(gd.disk);
 810        return 0;
 811
 812probe_fail_toc:
 813        blk_cleanup_queue(gd.gdrom_rq);
 814probe_fail_requestq:
 815        free_irq(HW_EVENT_GDROM_DMA, &gd);
 816        free_irq(HW_EVENT_GDROM_CMD, &gd);
 817probe_fail_cmdirq_register:
 818probe_fail_cdrom_register:
 819        del_gendisk(gd.disk);
 820probe_fail_no_disk:
 821        kfree(gd.cd_info);
 822        unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 823        gdrom_major = 0;
 824probe_fail_no_mem:
 825        printk(KERN_WARNING "GDROM: Probe failed - error is 0x%X\n", err);
 826        return err;
 827}
 828
 829static int __devexit remove_gdrom(struct platform_device *devptr)
 830{
 831        flush_scheduled_work();
 832        blk_cleanup_queue(gd.gdrom_rq);
 833        free_irq(HW_EVENT_GDROM_CMD, &gd);
 834        free_irq(HW_EVENT_GDROM_DMA, &gd);
 835        del_gendisk(gd.disk);
 836        if (gdrom_major)
 837                unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 838        unregister_cdrom(gd.cd_info);
 839
 840        return 0;
 841}
 842
 843static struct platform_driver gdrom_driver = {
 844        .probe = probe_gdrom,
 845        .remove = __devexit_p(remove_gdrom),
 846        .driver = {
 847                        .name = GDROM_DEV_NAME,
 848        },
 849};
 850
 851static int __init init_gdrom(void)
 852{
 853        int rc;
 854        gd.toc = NULL;
 855        rc = platform_driver_register(&gdrom_driver);
 856        if (rc)
 857                return rc;
 858        pd = platform_device_register_simple(GDROM_DEV_NAME, -1, NULL, 0);
 859        if (IS_ERR(pd)) {
 860                platform_driver_unregister(&gdrom_driver);
 861                return PTR_ERR(pd);
 862        }
 863        return 0;
 864}
 865
 866static void __exit exit_gdrom(void)
 867{
 868        platform_device_unregister(pd);
 869        platform_driver_unregister(&gdrom_driver);
 870        kfree(gd.toc);
 871}
 872
 873module_init(init_gdrom);
 874module_exit(exit_gdrom);
 875MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
 876MODULE_DESCRIPTION("SEGA Dreamcast GD-ROM Driver");
 877MODULE_LICENSE("GPL");
 878