Add support for GD-Rom device [LWN.net] (original) (raw)

| From: | | "Adrian McMenamin" lkmladrian@gmail.com | | ----------------- | | ------------------------------------------------------------------------------------------------------------------------- | | To: | | linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org, "Paul Mundt" lethal@linux-sh.org, axboe@kernel.dk | | Subject: | | [PATCH - SH/Dreamcast] Add support for GD-Rom device | | Date: | | Thu, 20 Dec 2007 23:59:52 +0000 | | Message-ID: | | 8b67d60712201559h5dbb2a17q8f16223b26b88006@mail.gmail.com | | Archive‑link: | | Article |

This patch adds support for the CD Rom device (called a "GD Rom") on the SEGA Dreamcast.This device has a command block similar to a standard ATA-3 device, though implements Sega's proprietary packet interface - the so-called "Sega Packet Interface".

There have been previous GD Rom drivers for Linux knocking about (though never anywhere near the mainline), though this is a new driver and most importantly uses DMA and not PIO for reads. It also directly supports the SEGA proprietary GD-Rom format.

This is the second posting and I think I've taken on board all or almost all the suggestions/change requests made last time. But grateful for all comments.

This is targetted at Paul Mundt's 2.6.25 queue, but should also compile against 2.6.24-rc5

I am using it play mp3s off CD even as I write this and it seems to work pretty well :)

Signed-off by: Adrian McMenamin adrian@mcmen.demon.co.uk

diff -ruN linux-2.6-orig/drivers/block/Kconfig linux-2.6/drivers/block/Kconfig --- linux-2.6-orig/drivers/block/Kconfig 2007-12-15 22:23:47.000000000 +0000 +++ linux-2.6/drivers/block/Kconfig 2007-12-20 23:36:15.000000000 +0000 @@ -105,6 +105,18 @@ "MicroSolutions backpack protocol", "DataStor Commuter protocol" etc.).

+config GDROM + tristate "SEGA Dreamcast GD-ROM drive" + depends on SH_DREAMCAST + help + A standard SEGA Dreamcast comes with a modified CD ROM drive called a + "GD-ROM" by SEGA to signify it is capable of reading special disks + with up to 1 GB of data. This drive will also read standard CD ROM + disks. Select this option to access any disks in your GD ROM drive.

•      Most users will want to say "Y" here.

•  You can also build this as a module - which will be called gdrom.ko

• source "drivers/block/paride/Kconfig"

  config BLK_CPQ_DA

@@ -425,10 +437,4 @@ block device driver. It communicates with a back-end driver in another domain which drives the actual block device.

-config VIRTIO_BLK - tristate "Virtio block driver (EXPERIMENTAL)" - depends on EXPERIMENTAL && VIRTIO - ---help--- - This is the virtual block driver for lguest. Say Y or M.

endif # BLK_DEV diff -ruN linux-2.6-orig/drivers/cdrom/gdrom.c linux-2.6/drivers/cdrom/gdrom.c --- linux-2.6-orig/drivers/cdrom/gdrom.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6/drivers/cdrom/gdrom.c 2007-12-20 23:36:15.000000000 +0000 @@ -0,0 +1,810 @@ +/* GD ROM driver for the SEGA Dreamcast

• • copyright Adrian McMenamin, 2007
• • With thanks to Marcus Comstedt and Nathan Keynes
• • for work in reversing PIO and DMA
• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License as published by
• • the Free Software Foundation; either version 2 of the License, or
• • (at your option) any later version.
• • This program is distributed in the hope that it will be useful,
• • but WITHOUT ANY WARRANTY; without even the implied warranty of
• • MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
• • GNU General Public License for more details.
• • You should have received a copy of the GNU General Public License along
• • with this program; if not, write to the Free Software Foundation, Inc.,
• • 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
• */
• +#include <linux/init.h>

+#include <linux/module.h> +#include <linux/fs.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/dma-mapping.h> +#include <linux/cdrom.h> +#include <linux/genhd.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/interrupt.h> +#include <linux/device.h> +#include <linux/wait.h> +#include <linux/workqueue.h> +#include <linux/platform_device.h> +#include <asm/io.h> +#include <asm/dma.h> +#include <asm/delay.h> +#include <asm/mach/dma.h> +#include <asm/mach/sysasic.h> + +#define GDROM_DEV_NAME "gdrom" +#define GD_SESSION_OFFSET 150 + +/* GD Rom commands / +#define GDROM_COM_SOFTRESET 0x08 +#define GDROM_COM_EXECDIAG 0x90 +#define GDROM_COM_PACKET 0xA0 +#define GDROM_COM_IDDEV 0xA1 + +/ GD Rom registers */ +#define GDROM_BASE_REG 0xA05F7000 +#define GDROM_ALTSTATUS_REG (GDROM_BASE_REG + 0x18) +#define GDROM_DATA_REG (GDROM_BASE_REG + 0x80) +#define GDROM_ERROR_REG (GDROM_BASE_REG + 0x84) +#define GDROM_INTSEC_REG (GDROM_BASE_REG + 0x88) +#define GDROM_SECNUM_REG (GDROM_BASE_REG + 0x8C) +#define GDROM_BCL_REG (GDROM_BASE_REG + 0x90) +#define GDROM_BCH_REG (GDROM_BASE_REG + 0x94) +#define GDROM_DSEL_REG (GDROM_BASE_REG + 0x98) +#define GDROM_STATUSCOMMAND_REG (GDROM_BASE_REG + 0x9C) +#define GDROM_RESET_REG (GDROM_BASE_REG + 0x4E4) + +#define GDROM_DMA_STARTADDR_REG (GDROM_BASE_REG + 0x404) +#define GDROM_DMA_LENGTH_REG (GDROM_BASE_REG + 0x408) +#define GDROM_DMA_DIRECTION_REG (GDROM_BASE_REG + 0x40C) +#define GDROM_DMA_ENABLE_REG (GDROM_BASE_REG + 0x414) +#define GDROM_DMA_STATUS_REG (GDROM_BASE_REG + 0x418) +#define GDROM_DMA_WAIT_REG (GDROM_BASE_REG + 0x4A0) +#define GDROM_DMA_ACCESS_CTRL_REG (GDROM_BASE_REG + 0x4B8) + +#define GDROM_HARD_SECTOR 2048 +#define BLOCK_LAYER_SECTOR 512 +#define GD_TO_BLK 4 + +static struct platform_device *pd; +static int gdrom_major; +static wait_queue_head_t command_queue; +static wait_queue_head_t request_queue; + +static DEFINE_SPINLOCK(gdrom_lock); +static void gdrom_readdisk_dma(struct work_struct *work); +static DECLARE_WORK(work, gdrom_readdisk_dma); +static LIST_HEAD(gdrom_deferred); + +struct gdromtoc { + unsigned int entry[99]; + unsigned int first, last; + unsigned int leadout; +}; + +static struct gdrom_unit { + struct gendisk *disk; + struct cdrom_device_info *cd_info; + int status; + int pending; + int transfer; + char disk_type; + struct gdromtoc *toc; + struct request_queue *gdrom_rq; +} gd; + +struct gdrom_id { + char mid; + char modid; + char verid; + char padA[13]; + char mname[16]; + char modname[16]; + char firmver[16]; + char padB[16]; +}; + +static int gdrom_getsense(short *bufstring); +static int gdrom_packetcommand(struct cdrom_device_info * cd_info, struct packet_command *command); +static int gdrom_hardreset(struct cdrom_device_info cd_info); + +static void gdrom_wait_clrbusy(void) +{ + / long timeouts - typical for a CD Rom / + unsigned long timeout = jiffies + HZ * 60; + while ((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) && (time_before(jiffies, timeout))) + cpu_relax(); +} + +static void gdrom_wait_busy_sleeps(void) +{ + unsigned long timeout; + / Wait to get busy first / + timeout = jiffies + HZ * 60; + while (((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) == 0) && (time_before(jiffies, timeout))) + cpu_relax(); + / Now wait for busy to clear */ + gdrom_wait_clrbusy(); +} + +static void gdrom_identifydevice(void *buf) +{ + int c; + short data = buf; + gdrom_wait_clrbusy(); + ctrl_outb(GDROM_COM_IDDEV, GDROM_STATUSCOMMAND_REG); + gdrom_wait_busy_sleeps(); + / now read in the data / + for (c = 0; c < 40; c++) + data[c] = ctrl_inw(GDROM_DATA_REG); +} + +static void gdrom_spicommand(void *spi_string, int buflen) +{ + short *cmd = spi_string; + /* ensure IRQ_WAIT is set */ + ctrl_outb(0x08, GDROM_ALTSTATUS_REG); + /* specify how many bytes we expect back */ + ctrl_outb(buflen & 0xFF, GDROM_BCL_REG); + ctrl_outb((buflen >> 8) & 0xFF, GDROM_BCH_REG); + / other parameters / + ctrl_outb(0, GDROM_INTSEC_REG); + ctrl_outb(0, GDROM_SECNUM_REG); + ctrl_outb(0, GDROM_ERROR_REG); + / Wait until we can go / + gdrom_wait_clrbusy(); + ctrl_outb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG); + while ((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x88) != 8) + ; / wait for DRQ to be set to 1 / + outsw(PHYSADDR(GDROM_DATA_REG), cmd, 6); +} + +/ gdrom_command_executediagnostic:

• • Used to probe for presence of working GDROM
• • Restarts GDROM device and then applies standard ATA 3
• • Execute Diagnostic Command: a return of '1' indicates device 0
• • present and device 1 absent
• */ +static char gdrom_execute_diagnostic(void) +{
• gdrom_hardreset(gd.cd_info);
• gdrom_wait_clrbusy();
• ctrl_outb(GDROM_COM_EXECDIAG, GDROM_STATUSCOMMAND_REG);
• gdrom_wait_busy_sleeps();
• return ctrl_inb(GDROM_ERROR_REG); +}
• +/*
• • Prepare disk command
• • byte 0 = 0x70
• • byte 1 = 0x1f
• */ +static int gdrom_preparedisk_cmd(void) +{
• struct packet_command *spin_command;
• spin_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
• if (!spin_command)

•   return -ENOMEM;

• spin_command->cmd[0] = 0x70;
• spin_command->cmd[2] = 0x1f;
• spin_command->buflen = 0;
• gd.pending = 1;
• gdrom_packetcommand(gd.cd_info, spin_command);
• /* 60 second timeout */
• wait_event_interruptible_timeout(command_queue, gd.pending == 0, HZ * 60);
• gd.pending = 0;
• kfree(spin_command);
• if ((gd.status & 0x01) != 0) {

•   /* log an error */

•   gdrom_getsense(NULL);

•   return -EIO;

• }
• return 0; +}
• +/*
• • Read TOC command
• • byte 0 = 0x14
• • byte 1 = session
• • byte 3 = sizeof TOC >> 8 ie upper byte
• • byte 4 = sizeof TOC & 0xff ie lower byte
• */ +static int gdrom_readtoc_cmd(struct gdromtoc *toc, int session) +{
• int tocsize;
• struct packet_command *toc_command;
• toc_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
• if (!toc_command)

•   return -ENOMEM;

• tocsize = sizeof(struct gdromtoc);
• toc_command->cmd[0] = 0x14;
• toc_command->cmd[1] = session;
• toc_command->cmd[3] = tocsize >> 8;
• toc_command->cmd[4] = tocsize & 0xff;
• toc_command->buflen = tocsize;
• gd.pending = 1;
• gdrom_packetcommand(gd.cd_info, toc_command);
• wait_event_interruptible_timeout(command_queue, gd.pending == 0, HZ * 60);
• gd.pending = 0;
• insw(PHYSADDR(GDROM_DATA_REG), toc, tocsize/2);
• kfree(toc_command);
• if ((gd.status & 0x01) != 0)

•   return -EINVAL;

• return 0; +}
• +/* TOC helpers */ +static int get_entry_lba(int track) +{
• return (cpu_to_be32(track & 0xffffff00) - GD_SESSION_OFFSET); +}
• +static int get_entry_q_ctrl(int track) +{
• return (track & 0x000000f0) >> 4; +}
• +static int get_entry_track(int track) +{
• return (track & 0x0000ff00) >> 8; +}
• +static int gdrom_get_last_session(struct cdrom_device_info *cd_info, struct cdrom_multisession *ms_info) +{
• struct gdromtoc *tocA, *tocB;
• int fentry, lentry, track, data, tocuse;
• int err = -ENOMEM;
• tocA = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
• if (!tocA)

•   goto exit;	

• tocB = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
• if (!tocB)

•   goto clean_tocA;

• tocuse = 1;
• err = gdrom_readtoc_cmd(tocB, 1);
• if (err) {

•   tocuse = 0;

•   err = gdrom_readtoc_cmd(tocA, 0);

•   if (err) {

•      err = -ENXIO;

•      printk(KERN_INFO "Could not get CD table of contents\n");

•      goto clean_tocB;

•   }	

• } else

•   printk(KERN_DEBUG "Disk is GDROM\n");

• kfree(gd.toc);
• if (tocuse) {

•   gd.toc = tocB;

•   kfree(tocA);

• } else {

•   gd.toc = tocA;

•   kfree(tocB);

• }
• fentry = get_entry_track(gd.toc->first);
• lentry = get_entry_track(gd.toc->last);
• /* Find the first data track */
• track = get_entry_track(gd.toc->last);
• do {

•   data = gd.toc->entry[track - 1];

•   if (get_entry_q_ctrl(data))

•      break;	/* ie a real data track */

•   track--;

• } while (track >= fentry);
• if ((track > 100) || (track < get_entry_track(gd.toc->first))) {

•   gdrom_getsense(NULL);

•   printk(KERN_INFO "GDROM: No data on the last session of the CD\n");

•   return -ENXIO;

• }
• ms_info->addr_format = CDROM_LBA;
• ms_info->addr.lba = get_entry_lba(data);
• ms_info->xa_flag = 1;
• return 0;
• +clean_tocB:
• kfree(tocB); +clean_tocA:
• kfree(tocA); +exit:
• return err; +}
• +static int gdrom_open(struct cdrom_device_info *cd_info, int purpose) +{
• /* spin up the disk */
• return gdrom_preparedisk_cmd(); +}
• +/* this function is required even if empty */ +static void gdrom_release(struct cdrom_device_info *cd_info) +{ +}
• +static int gdrom_drivestatus(struct cdrom_device_info *cd_info, int ignore) +{
• /* read the sense key */
• char sense = ctrl_inb(GDROM_ERROR_REG);
• sense &=0xF0;
• if (sense == 0)

•   return CDS_DISC_OK;

• if (sense == 0x20)

•   return CDS_DRIVE_NOT_READY;

• /* default */
• return CDS_NO_INFO; +}
• +static int gdrom_mediachanged(struct cdrom_device_info *cd_info, int ignore) +{
• /* check the sense key */
• return ((ctrl_inb(GDROM_ERROR_REG) & 0xF0) == 0x60); +}
• +/* reset the G1 bus */ +static int gdrom_hardreset(struct cdrom_device_info * cd_info) +{
• int count;
• ctrl_outl(0x1fffff, GDROM_RESET_REG);
• for (count = 0xa0000000; count < 0xa0200000; count += 4)

•   ctrl_inl(count);

• return 0; +}
• +static int gdrom_packetcommand(struct cdrom_device_info * cd_info, struct packet_command *command) +{
• gdrom_spicommand(&command->cmd, command->buflen);
• /* keep the function like the universal CD Rom one

•  * though the return value is meaningless */	

• return 0; +}
• +/* Get Sense SPI command
• • From Marcus Comstedt
• • cmd = 0x13
• • cmd + 4 = length of returned buffer
• • Returns 5 16 bit words
• */ +static int gdrom_getsense(short *bufstring) +{
• struct packet_command *sense_command;
• short sense[5];
• char sense_key;
• if (gd.pending)

•   return -EIO;

• /* allocate command and buffer */
• sense_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
• if (!sense_command)

•   return -ENOMEM;

• sense_command->cmd[0] = 0x13;
• sense_command->cmd[4] = 10;
• sense_command->buflen = 10;
• gd.pending = 1;
• gdrom_packetcommand(gd.cd_info, sense_command);
• /* 60 second timeout */
• wait_event_interruptible_timeout(command_queue, gd.pending == 0, HZ * 60);
• gd.pending = 0;
• kfree(sense_command);
• insw(PHYSADDR(GDROM_DATA_REG), &sense, 5);
• if (sense[1] & 40) {

•   printk(KERN_INFO "GDROM: Drive not ready - command aborted\n");

•   return -EIO;

• }
• sense_key = sense[1] & 0x0F;
• switch (sense_key){
• case 0xB:

•   printk(KERN_INFO "GDROM: Command aborted\n");

•   break;

• case 0x7:

•   printk(KERN_INFO "GDROM: Data protection error\n");

•   break;

• case 0x6:

•   printk(KERN_NOTICE "GDROM: Unit needs attention - possible disk switch\n");

•   break;

• case 0x5:

•   printk(KERN_INFO "GDROM: Illegal request - command has failed\n");

•   break;

• case 0x4:

•   printk(KERN_CRIT "GDROM: Hardware error\n");

•   break;

• case 0x3:

•   printk(KERN_WARNING "GDROM: Disk read error\n");

•   break;

• case 0x2:

•   printk(KERN_INFO "GDROM: Not ready\n");

•   break;

• case 0x1:

•   printk(KERN_DEBUG "GDROM: Recovered from error\n");

•   break;

• case 0x0:

•   /*success - stay silent*/

•   break;

• default:

•   printk(KERN_INFO "GDROM: Unknown error\n");

• }
• if (bufstring)

•   memcpy(bufstring, &sense[4], 2); /* return additional sense data */

• if (sense_key < 2)

•   return 0;

• return -EIO; +}
• +static struct cdrom_device_ops gdrom_ops = {
• .open = gdrom_open,
• .release = gdrom_release,
• .drive_status = gdrom_drivestatus,
• .media_changed = gdrom_mediachanged,
• .get_last_session = gdrom_get_last_session,
• .reset = gdrom_hardreset,
• .capability = CDC_MULTI_SESSION | CDC_MEDIA_CHANGED |

•           CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R,

• .n_minors = 1, +};
• +static int gdrom_bdops_open(struct inode *inode, struct file *file) +{
• return cdrom_open(gd.cd_info, inode, file); +}
• +static int gdrom_bdops_release(struct inode *inode, struct file *file) +{
• return cdrom_release(gd.cd_info, file); +}
• +static int gdrom_bdops_mediachanged(struct gendisk *disk) +{
• return cdrom_media_changed(gd.cd_info); +}
• +static int gdrom_bdops_ioctl(struct inode *inode, struct file *file, unsigned cmd, unsigned long arg) +{
• return cdrom_ioctl(file, gd.cd_info, inode, cmd, arg); +}
• +static struct block_device_operations gdrom_bdops = {
• .owner = THIS_MODULE,
• .open = gdrom_bdops_open,
• .release = gdrom_bdops_release,
• .media_changed = gdrom_bdops_mediachanged,
• .ioctl = gdrom_bdops_ioctl, +};
• +static irqreturn_t gdrom_command_interrupt(int irq, void *dev_id) +{
• gd.status = ctrl_inb(GDROM_STATUSCOMMAND_REG);
• if (gd.pending != 1)

•   return IRQ_HANDLED;

• gd.pending = 0;
• wake_up_interruptible(&command_queue);
• return IRQ_HANDLED; +}
• +static irqreturn_t gdrom_dma_interrupt(int irq, void *dev_id) +{
• gd.status = ctrl_inb(GDROM_STATUSCOMMAND_REG);
• if (gd.transfer != 1)

•   return IRQ_HANDLED;

• gd.transfer = 0;
• wake_up_interruptible(&request_queue);
• return IRQ_HANDLED; +}
• +static int gdrom_set_command_interrupt_handler(void) +{
• /* need a queue to wait in */
• init_waitqueue_head(&command_queue);
• return request_irq(HW_EVENT_GDROM_CMD, gdrom_command_interrupt, IRQF_DISABLED, "gdrom_command", &gd); +}
• +static int gdrom_set_dma_interrupt_handler(void) +{
• init_waitqueue_head(&request_queue);
• return request_irq(HW_EVENT_GDROM_DMA, gdrom_dma_interrupt, IRQF_DISABLED, "gdrom_dma", &gd); +}
• +/* Implement DMA read using SPI command
• • 0 -> 0x30
• • 1 -> mode
• • 2 -> block >> 16
• • 3 -> block >> 8
• • 4 -> block
• • 8 -> sectors >> 16
• • 9 -> sectors >> 8
• • 10 -> sectors
• */ +static void gdrom_readdisk_dma(struct work_struct *work) +{
• int err, block, block_cnt;
• struct packet_command *read_command;
• struct list_head *elem, *next;
• struct request *req;
• unsigned long timeout;
• if (list_empty(&gdrom_deferred))

•   return;

• list_for_each_safe(elem, next, &gdrom_deferred) {

•   req = list_entry(elem, struct request, queuelist);

•   block = req->sector/GD_TO_BLK + GD_SESSION_OFFSET;

•   block_cnt = req->nr_sectors/GD_TO_BLK;

•   ctrl_outl(PHYSADDR(req->buffer), GDROM_DMA_STARTADDR_REG);

•   ctrl_outl(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);

•   ctrl_outl(1, GDROM_DMA_DIRECTION_REG);

•   ctrl_outl(1, GDROM_DMA_ENABLE_REG);

•   /* send command */

•   read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);

•   if (!read_command) {

•      err = -ENOMEM;

•      goto end_request;

•   }		

•   read_command->cmd[0] = 0x30;

•   read_command->cmd[1] = 0x20;

•   read_command->cmd[2] = (block >> 16) & 0xFF;

•   read_command->cmd[3] = (block >> 8) & 0xFF;

•   read_command->cmd[4] = block & 0xFF;

•   read_command->cmd[8] = (block_cnt >> 16) & 0xFF;

•   read_command->cmd[9] = (block_cnt >> 8) & 0xFF;

•   read_command->cmd[10] = block_cnt & 0xFF;

•   /* set for DMA */

•   ctrl_outb(1, GDROM_ERROR_REG);

•   /* other parameters */

•   ctrl_outb(0, GDROM_SECNUM_REG);

•   ctrl_outb(0, GDROM_BCL_REG);

•   ctrl_outb(0, GDROM_BCH_REG);

•   ctrl_outb(0, GDROM_DSEL_REG);

•   ctrl_outb(0, GDROM_INTSEC_REG);

•   /* In multiple DMA transfers need to wait */

•   timeout = jiffies + HZ / 2;

•   while ((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x80) &&

(time_before(jiffies, timeout))) + cpu_relax(); + ctrl_outb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG); + timeout = jiffies + HZ / 2; + while (((ctrl_inb(GDROM_ALTSTATUS_REG) & 0x88) != 8) && (time_before(jiffies, timeout))) + cpu_relax(); /* wait for DRQ to be set to 1 / + gd.pending = 1; + gd.transfer = 1; + outsw(PHYSADDR(GDROM_DATA_REG), &read_command->cmd, 6); + timeout = jiffies + HZ / 2; + while ((ctrl_inb(GDROM_DMA_STATUS_REG)) && (time_before(jiffies, timeout))) + cpu_relax(); + ctrl_outb(1, GDROM_DMA_STATUS_REG); + / 5 second error margin here seems more reasonable / + wait_event_interruptible_timeout(request_queue, gd.transfer == 0, HZ * 5); + err = ctrl_inb(GDROM_DMA_STATUS_REG); + err = gd.transfer; + gd.transfer = 0; + gd.pending = 0; + kfree(read_command); + / now seek to take the request spinlock

•      * before handling ending the request	*/

  +end_request:

•   spin_lock(&gdrom_lock);

•   list_del_init(&req->queuelist);

•   blk_requeue_request(gd.gdrom_rq, req);

•   if (err)

•      end_request(req, 0);

•   else

•      end_request(req, 1);

•   spin_unlock(&gdrom_lock);

• } +}

• +static void gdrom_request_handler_dma(struct request *req) +{

• /* dequeue, add to list of deferred work

•  * and then schedule workqueue */

• blkdev_dequeue_request(req);

• list_add_tail(&req->queuelist, &gdrom_deferred);

• schedule_work(&work); +}

• +static void gdrom_request(struct request_queue *rq) +{

• struct request *req;

• unsigned long pages;

• pages = rq->backing_dev_info.ra_pages;

• while ((req = elv_next_request(rq)) != NULL) {

•   if (! blk_fs_request(req)) {

•      printk(KERN_DEBUG "GDROM: Non-fs request ignored\n");

•      end_request(req, 0);

•   }

•   if (rq_data_dir(req) != READ) {

•      printk(KERN_NOTICE "GDROM: Read only device - write request ignored\n");

•      end_request(req, 0);

•   }

•   if (req->nr_sectors)

•      gdrom_request_handler_dma(req);

•   else

•      end_request(req, 0);

• } +}

• +/* Print string identifying GD ROM device */ +static int gdrom_outputversion(void) +{

• struct gdrom_id *id;

• char *model_name, *manuf_name, *firmw_ver;

• int err = -ENOMEM;

• /* query device ID */

• id = kzalloc(sizeof(struct gdrom_id), GFP_KERNEL);

• if (!id)

•   return err;

• gdrom_identifydevice(id);

• model_name = kstrndup(id->modname, 16, GFP_KERNEL);

• if (!model_name)

•   goto free_id;

• manuf_name = kstrndup(id->mname, 16, GFP_KERNEL);

• if (!manuf_name)

•   goto free_model_name;

• firmw_ver = kstrndup(id->firmver, 16, GFP_KERNEL);

• if (!firmw_ver)

•   goto free_manuf_name;

• printk(KERN_INFO "GDROM: %s from %s with firmware %s\n", model_name, manuf_name, firmw_ver);

• err = 0;

• kfree(firmw_ver); +free_manuf_name:

• kfree(manuf_name); +free_model_name:

• kfree(model_name); +free_id:

• kfree(id);

• return err; +}

• +/* set the default mode for DMA transfer */ +static void __init gdrom_init_dma_mode(void) +{

• ctrl_outb(0x13, GDROM_ERROR_REG);

• ctrl_outb(0x22, GDROM_INTSEC_REG);

• gdrom_wait_clrbusy();

• ctrl_outb(0xEF, GDROM_STATUSCOMMAND_REG);

• gdrom_wait_busy_sleeps();

• ctrl_outl(0x8843407F, GDROM_DMA_ACCESS_CTRL_REG); /* memory setting */

• ctrl_outl(9, GDROM_DMA_WAIT_REG); /* DMA word setting */ +}

• +/*

• • register this as a block device and as compliant with the
• • universal CD Rom driver interface

• */ +static int __init probe_gdrom(struct platform_device *devptr) +{

• char err;

• gd.toc = NULL;

• err = gdrom_execute_diagnostic();

• if (err == 1){

•   if (gdrom_outputversion())

•      return -ENOMEM;

• } else {

•   printk(KERN_WARNING "Probe for GDROM failed with error 0x%X\n", err);

•   return -ENODEV;

• }

• gdrom_major = register_blkdev(0, GDROM_DEV_NAME);

• if (gdrom_major <= 0)

•   return gdrom_major;

• printk(KERN_INFO "GDROM: Block device is registered with major number %d\n", gdrom_major);

• gd.cd_info = kzalloc(sizeof(struct cdrom_device_info), GFP_KERNEL);

• if (!gd.cd_info) {

•   err = -ENOMEM;

•   goto probe_fail_no_mem;

• }

• gd.cd_info->ops = &gdrom_ops;

• gd.cd_info->capacity = 1;

• sprintf(gd.cd_info->name, GDROM_DEV_NAME);

• gd.cd_info->mask = CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|CDC_SELECT_DISC;

• gd.disk = alloc_disk(1);

• if (!gd.disk) {

•   err = -ENODEV;

•   goto probe_fail_no_disk;

• }

• gd.disk->major = gdrom_major;

• gd.disk->first_minor = 1;

• gd.disk->minors = 1;

• sprintf(gd.disk->disk_name, GDROM_DEV_NAME);

• if (register_cdrom(gd.cd_info)){

•   err = -ENODEV;

•   goto probe_fail_cdrom_register;

• }

• gd.disk->fops = &gdrom_bdops;

• /* latch on to the interrupt */

• err = gdrom_set_command_interrupt_handler();

• if (err)

•   goto probe_fail_cmdirq_register;

• err = gdrom_set_dma_interrupt_handler();

• if (err)

•   goto probe_fail_dmairq_register;

• gd.gdrom_rq = blk_init_queue(gdrom_request, &gdrom_lock);

• if (!gd.gdrom_rq)

•   goto probe_fail_requestq;

• blk_queue_hardsect_size(gd.gdrom_rq, GDROM_HARD_SECTOR);

• /* using DMA so memory will need to be contiguous */

• blk_queue_max_hw_segments(gd.gdrom_rq, 1);

• /* set a large max size to get most from DMA */

• blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);

• gd.disk->queue = gd.gdrom_rq;

• gdrom_init_dma_mode();

• add_disk(gd.disk);

• return 0;

• +probe_fail_requestq:

• free_irq(HW_EVENT_GDROM_DMA, &gd); +probe_fail_dmairq_register:

• free_irq(HW_EVENT_GDROM_CMD, &gd); +probe_fail_cmdirq_register: +probe_fail_cdrom_register:

• del_gendisk(gd.disk); +probe_fail_no_disk:

• kfree(gd.cd_info);

• unregister_blkdev(gdrom_major, GDROM_DEV_NAME);

• gdrom_major = 0; +probe_fail_no_mem:

• printk(KERN_WARNING "GDROM: Could not probe for device - error is 0x%X\n", err);

• return err; +}

• +static int remove_gdrom(struct platform_device *devptr) +{

• blk_cleanup_queue(gd.gdrom_rq);

• free_irq(HW_EVENT_GDROM_CMD, &gd);

• free_irq(HW_EVENT_GDROM_DMA, &gd);

• del_gendisk(gd.disk);

• if (gdrom_major)

•   unregister_blkdev(gdrom_major, GDROM_DEV_NAME);

• return unregister_cdrom(gd.cd_info); +}

• +static struct platform_driver gdrom_driver = {

• .probe = probe_gdrom,

• .remove = remove_gdrom,

• .driver = {

•      .name = GDROM_DEV_NAME,

• }, +};

• +static int __init init_gdrom(void) +{

• int rc;

• rc = platform_driver_register(&gdrom_driver);

• if (rc) {

•   printk(KERN_INFO "Could not register GDROM driver - error 0x%X\n", rc);

•   return -EPERM;

• }

• pd = platform_device_register_simple(GDROM_DEV_NAME, -1, NULL, 0);

• if (IS_ERR(pd)) {

•   platform_driver_unregister(&gdrom_driver);

•   return -ENODEV;

• }

• return 0; +}

• +static void __exit exit_gdrom(void) +{

• platform_device_unregister(pd);

• platform_driver_unregister(&gdrom_driver);

• kfree(gd.toc); +}

• +module_init(init_gdrom); +module_exit(exit_gdrom); +MODULE_AUTHOR("Adrian McMenamin adrian@mcmen.demon.co.uk"); +MODULE_DESCRIPTION("SEGA Dreamcast GD-ROM Driver"); +MODULE_LICENSE("GPL"); diff -ruN linux-2.6-orig/drivers/cdrom/Makefile linux-2.6/drivers/cdrom/Makefile --- linux-2.6-orig/drivers/cdrom/Makefile 2007-12-15 22:23:47.000000000 +0000 +++ linux-2.6/drivers/cdrom/Makefile 2007-12-20 23:36:15.000000000 +0000 @@ -11,3 +11,4 @@ obj-$(CONFIG_CDROM_PKTCDVD) += cdrom.o

  obj-$(CONFIG_VIOCD) += viocd.o cdrom.o

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