SR(4S) — DEVICES AND NETWORK INTERFACES

NAME

sr − driver for CDROM SCSI controller

CONFIG — SOLBOURNE SERIES 4, 5, 5E, 6

controller si0 at kbio ? csr ? priority 2
disk sr0 at si0 drive 0x06

CONFIG — SOLBOURNE S4000

controller si0 at obio ? csr 0x20 priority 4
disk sr0 at si0 drive 0x06

All SCSI devices in a Solbourne system use a three layer device driver scheme. The top layer supports a specific type of device (for example disk sd(4s), or cdrom sr(4s)), the middle layer contains common code (scsi(4)), and the lower layer supports specific host adaptor hardware (for example SCSI IOASIC si(4), or SCSI VMEbus sv(4s)). This man page describes the top layer operations for SCSI CDROM. It provides a standard interface ( see cdromio(4)) to CDROM devices on the SCSI bus.

The controller lines above specify SCSI host adaptors on a Solbourne system (see si(4S)). The disk lines specify the CDROM drive on each controller.

The drive value is calculated using the formula:

16∗lun+target

where target is the SCSI target, and lun is the SCSI logical unit.

Bit 0 of flags may be SET to specify that the device does NOT support disconnect/reconnect on the SCSI bus. Bit 1 of flags may be SET to specify that the driver should negotiate with the device for synchronous SCSI transfers. Bit 2 of flags may be SET to specify that the device does NOT support parity on the SCSI bus. Bit 3 of flags may be SET to specify that standard commands that are going to transfer a small amount of data can, if nothing else is active, avoid doing a disconnect. Bit 4 of flags may be set to specify the device supports multiple luns active simultaneously. Bit 5 of flags may be set to specify the device supports only simple (COMMAND_COMPLETE) SCSI messages. Bit 6 of flags may be set to specify that command combining optimizations can be performed.

DESCRIPTION

CDROM is a removable read-only direct-access device connected to the system’s SCSI bus. CDROM drives are designed to work with any disc that meets the Sony-Philips “red-book” or “yellow-book” documents. They can read CDROM data discs, digital audio discs (Audio CD’s) or combined-mode discs (that is, some tracks are audio, some tracks are data). A CDROM disc is singled sided containing approximately 540 mega-bytes of data or 74 minutes of audio.

The CDROM drive controller is set up as SCSI target 6. There is only a single logical unit number 0; therefore, the minor device number is always 0.

Since all the other SCSI target ids has been reserved by the system, the standard system only supports one CDROM drive. The device names are /dev/sr0 for block device and /dev/rsr0 for character device.

The device driver supports open(2V), read(2V), close(2V) function calls through its block device and character device interface. In addition, it supports ioctl function call through the character device interface. When the device is first opened, the CDROM drive’s eject button will be disabled (which prevents the manual removal of the disc) until the last close(2V) is called.

CDROM Drive Support

This driver supports the SONY CDU-8012 drive controller, the TOSHIBA drive controller, and other CDROM drives which have implemented the SCSI-2 command set. The type of CDROM drive is determined using the SCSI inquiry command.

There is no volume label stored on the CDROM. The disc geometry and partitioning information is always the same. If the CDROM is in ISO 9660 or High Sierra Disk format, it can be mounted as a file system.

FILES

/dev/sr0 block files

/dev/rsr0 raw files

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