ata(7D) 							      Devices								   ata(7D)

NAME

       ata - AT attachment disk driver

SYNOPSIS

       ide@unit-address

DESCRIPTION

       The  ata  driver  supports disk and ATAPI CD/DVD devices conforming to the AT Attachment specification including IDE interfaces. Support is
       provided for both parallel ATA (PATA) and serial ATA (SATA) interfaces.

       Refer to the Solaris x86 Hardware Compatibility List for a list of supported controllers.

PRECONFIGURE

       A PCI IDE controller can operate in compatibility mode or in PCI-native mode. If more than one controller is present in	the  system,  only
       one can operate in compatibility mode.

       If  two	PATA drives share the same controller, you must set one to master and the other to slave. If both a PATA disk drive and a PATA CD-
       ROM drive utilize the same controller, you can designate the disk drive as the master with the CD-ROM drive as the slave, although this	is
       not mandatory.

   Supported Settings
       Supported settings for the primary controller when in compatibility mode are:

	 o  IRQ Level: 14

	 o  I/O Address: 0x1F0

       Supported settings for the secondary controller when in compatibility mode are:

	 o  IRQ Level: 15

	 o  I/O Address: 0x170

       Note -  When in PCI-native mode, the IRQ and I/O address resources are configured by the system BIOS.

   Known Problems and Limitations
	 o  This driver does not support any RAID features present on a PATA/SATA controller. As a result, you should configure BIOS to select IDE
	    mode rather than RAID mode. Some systems may require updating BIOS to allow switching modes.

	 o  On some systems, the SATA controller must have option ROM enabled or BIOS will not consider SATA drives as bootable devices.

	 o  Panasonic LK-MC579B and the Mitsumi FX34005 IDE CD-ROM drives are not supported and cannot be used to install  the	Solaris  operating
	    environment.

	 o  CMD-604  is  unable  to handle simultaneous I/O on both IDE interfaces. This defect causes the Solaris software to hang if both inter-
	    faces are used. Use only the primary IDE interface at address 0x1F0.

	 o  The Solaris Volume Management software does not work with the Sony CDU-55E CD-ROM drive whether configured as device 0 or 1 (master or
	    slave). Comment out the following line in the /etc/vold.conf file to prevent vold from hanging the controller:

	    # use cdrom drive /dev/rdsk/c*s2 dev_cdrom.so cdrom%d

	 o  NEC CDR-260/CDR-260R/CDR-273 and Sony CDU-55E ATAPI CD-ROM drives might fail during installation.

	 o  Sony CDU-701 CD-ROM drives must be upgraded to use firmware version 1.0r or later to support booting from the CD.

CONFIGURATION

       The  ata  driver  properties are usually set in ata.conf. However, it may be convenient, or in some cases necessary, for you to set some of
       the DMA related properties as a system global boot environment property. You set or modify properties in the boot  environment  immediately
       prior  to  booting  the Solaris kernel by pressing ESC when prompted for the Solaris device configuration assistant.  You can also set boot
       environment properties using the eeprom(1M) command or by editing the bootenv.rc configuration file. If a  property  is	set  in  both  the
       driver's ata.conf file and the boot environment, the ata.conf property takes precedence.

       Property  modification  other  than  with  DCA are not effective until you reboot the system. If booting from hard disk or floppy disk, any
       property changes made with DCA will persist across future boots. If you boot from a CD/DVD, property changes persist to the installed  tar-
       get drive, but not to a subsequent boot of the CD/DVD.

       Direct  Memory  Access is enabled by default for disks and disabled for ATAPI CD/DVD devices.  If you are trying to enable DMA when booting
       from a CD/DVD, you must first set atapi-cd-dma-enabled to '1' using the DCA.

       ata-dma-enabled

	   This property is examined before the DMA properties	       discussed below. If it is set to '0,' DMA is  disabled  for  all  ATA/ATAPI
	   devices,  and  no  further  property  checks are made. If this property is absent or is set to '1,' DMA status is determined by further
	   examining one of the other properties listed below.

       ata-disk-dma-enabled

	   This property is examined only for ATA disk devices, and only if ata-dma-enabled is not set to '0.'

	   If ata-disk-dma-enabled set to '0,' DMA is disabled for all ATA disks in the system.  If this property is absent or set to '1,' DMA	is
	   enabled  for  all  ATA  disks  and no further property checks are made. If needed, this property should be created by the administrator
	   using the  DCA or the eeprom(1M) command.

       atapi-cd-dma-enabled

	   This property is examined only for ATAPI CD/DVD devices, and only if ata-dma-enabled is not set to '0.'

	   If atapi-cd-dma-enabled is absent or set to '0,' DMA is disabled for all ATAPI CD/DVD's. If set to '1,' DMA is enabled and  no  further
	   property checks are made.

	   The	Solaris installation program creates this property in the boot environment with a value of '0.'  It can be changed with the DCA or
	   eeprom(1M) as shown in the Example section of this manpage.

       atapi-other-dma-enabled

	   This property is examined only for non-CD/DVD ATAPI devices such as ATAPI tape drives, and only if ata-dma-enabled is not set to '0.'

	   If atapi-other-dma-enabled is set to '0,' DMA is disabled for all non-CD/DVD ATAPI devices. If this property is absent or set  to  '1,'
	   DMA is enabled and no further property checks are made.

	   If needed, this property should be created by the administrator using the  DCA or the eeprom(1M) command.

       drive0_block_factor
       drive1_block_factor

	   ATA	controllers  support  some amount of buffering (blocking). The purpose is to interrupt the host when an entire buffer full of data
	   has been read or written instead of using an interrupt for each sector. This reduces interrupt  overhead  and  significantly  increases
	   throughput. The driver interrogates the controller to find the buffer size. Some controllers hang when buffering is used, so the values
	   in the configuration file are used by the driver to reduce the effect of buffering (blocking). The values presented may be chosen  from
	   0x1, 0x2, 0x4, 0x8 and 0x10.

	   The values as shipped are set to 0x1, and they can be tuned to increase performance.

	   If your controller hangs when attempting to use higher block factors, you may be unable to reboot the system. For x86 based systems, it
	   is recommended that tuning be performed using a duplicate of the /platform/i86pc/kernel directory subtree. This ensures that a bootable
	   kernel subtree exists in the event of a failed test.

       ata-revert-to-defaults
       revert--<diskmodel>

	   When  rebooting or shutting down, the driver can set a feature which allows the drive to return to the power-on settings when the drive
	   receives a software reset (SRST) sequence. If this property is present and set to 1, the driver will  set  the  feature  to	revert	to
	   defaults  during  reset. Setting this property to 1 may prevent some systems from soft-rebooting and would require cycling the power to
	   boot the system. If this property is not present the system will not set the feature to revert to defaults during reset.

	   To determine the string to substitute for <diskmodel>, boot your system (you may have to press the reset  button  or  power-cycle)  and
	   then  view  /var/adm/messages.  Look for the string "IDE device at targ" or "ATAPI device at targ." The next line will contain the word
	   "model" followed by the model number and a comma. Ignore all characters except letters, digits, ".", "_",  and  "-".  Change  uppercase
	   letters to lower case. If the string revert-<diskmodel> is longer than 31 characters, use only the first 31 characters.

EXAMPLES

       Example 1: Sample ata Configuration File

       # for higher performance - set block factor to 16
	    drive0_block_factor=0x1 drive1_block_factor=0x1
	    max_transfer=0x100
	    flow_control="dmult" queue="qsort" disk="dadk" ;

       Example 2: Revert to defaults property

       revert-st320420a=1;

       Output of /var/adm/messages:

       Aug 17 06:49:43 caesar ata:[ID 640982 kern.info] IDE device at targ 0,
				  lun 0 lastlun 0x0
       Aug 17 06:49:43 caesar ata:[ID 521533 kern.info] model ST320420A, stat

       Example 3: Change DMA property within Solaris DCA

       To change one of the DMA properties within the Solaris Device Configuration Assistant:

       1.  Run the Solaris (x86 Edition) Device Configuration Assistant by pressing ESC when prompted soon after booting.

       2.  Press F2_Continue to scan for devices.

       3.  Press F2_Continue to display a list of  boot  devices on the Boot Solaris menu.

       4.  Go to the View/Edit Property Settings menu.

       5.  Press F4_Boot Tasks, select View/Edit Property  Settings, and press F2_Continue.

       6.  Select the property from the list and press F3_Change.

       7.  Type 0 or 1 and press F2_Continue.

       8.  Press F2_Back to return to the Boot Tasks menu.

       9.  Press F3_Back to return to the Boot Solaris menu.

       10. Select the device from which you want to boot and press F2_Continue.

       Example 4: Change DMA Property with eeprom(1M)

       To enable DMA for optical devices while the Solaris kernel is running with the eeprom(1M) system command:

       eeprom 'atapi-cd-dma-enabled=1'

FILES

       /platform/i86pc/kernel/drv/ata

	   Device driver.

       /platform/i86pc/kernel/drv/ata.conf

	   Configuration file.

       /boot/solaris/bootenv.rc

	   Boot environment variables file for Solaris x86. eeprom(1M) can be used to modify properties in this file.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |x86			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       eeprom(1M), attributes(5)

       INCITS T13 ATA/ATAPI-7 specifications

SunOS 5.10							    9 Oct 2004								   ata(7D)