ATA(4)							   BSD Kernel Interfaces Manual 						    ATA(4)

NAME

     ata, ar, acd, ad, afd, ast -- generic ATA/ATAPI disk controller driver

SYNOPSIS

     For ISA based ATA/ATAPI support:
     device isa
     device ata

     In /boot/device.hints:
     hint.ata.0.at="isa"
     hint.ata.0.port="0x1f0"
     hint.ata.0.irq="14"
     hint.ata.1.at="isa"
     hint.ata.1.port="0x170"
     hint.ata.1.irq="15"

     For PC98 based ATA/ATAPI support:
     device isa
     device ata

     In /boot/device.hints:
     hint.atacbus.0.at="isa"
     hint.atacbus.0.port="0x640"
     hint.atacbus.0.irq="9"

     For PCI based ATA/ATAPI support:
     device pci
     device ata

     To support ATA compliant disk drives:
     device atadisk

     To support ATA software RAID's:
     device ataraid

     To support ATAPI CDROM, DVD and CD/DVD burner drives:
     device atapicd

     To support ATAPI floppy drives:
     device atapifd

     To support ATAPI tape drives:
     device atapist

     To turn ata(4) subsystem controller drivers into cam(4) interface modules (disables all native ata(4) APIs and periperal drivers):
     options ATA_CAM

     The following tunables are settable from the loader:

     hw.ata.ata_dma
     set to 1 for DMA access, 0 for PIO (default is DMA).

     hw.ata.ata_dma_check_80pin
     set to 0 to disable the 80pin cable check (default is 1, check the cable)

     hw.ata.atapi_dma
     set to 1 for DMA access, 0 for PIO (default is DMA).

     hw.ata.wc
     set to 1 to enable Write Caching, 0 to disable (default is enabled).  WARNING: can cause data loss on power failures and crashes.

     hint.atapci.X.msi
     set to 1 to allow Message Signalled Interrupts (MSI) to be used by specified PCI ATA controller, if supported.

     hint.ata.X.devX.mode
     limits initial ATA mode for specified device on specified channel.

     hint.ata.X.mode
     limits initial ATA mode for every device on specified channel.

     hint.ata.X.pm_level
     controls SATA interface Power Management for specified channel, allowing to save some power by the cost of additional command latency.  Pos-
     sible values:
     0		   interface Power Management is disabled, default value.
     1		   device is allowed to initiate PM state change, host is passive.
     2		   host initiates PARTIAL PM state transition every time port becomes idle.
     3		   host initiates SLUMBER PM state transition every time port becomes idle.
     Modes 2 and 3 are implemented only for AHCI driver now.

DESCRIPTION

     The ata driver provides access to ATA (IDE) and SerialATA disk drives, ATAPI CDROM/DVD drives, ZIP/LS120 ATAPI drives and ATAPI tape drives
     connected to controllers according to the ATA/ATAPI standards.

     The currently supported ATA/SATA controller chips are:

     Acard:	     ATP850P, ATP860A, ATP860R, ATP865A, ATP865R.
     ALI:	     M5228, M5229, M5281, M5283, M5287, M5288, M5289.
     AMD:	     AMD756, AMD766, AMD768, AMD8111, CS5536.
     ATI:	     IXP200, IXP300, IXP400, IXP600, IXP700, IXP800.
     CMD:	     CMD646, CMD646U2, CMD648, CMD649.
     Cypress:	     Cypress 82C693.
     Cyrix:	     Cyrix 5530.
     HighPoint:      HPT302, HPT366, HPT368, HPT370, HPT371, HPT372, HPT372N, HPT374.
     Intel:	     6300ESB, 31244, PIIX, PIIX3, PIIX4, ESB2, ICH, ICH0, ICH2, ICH3, ICH4, ICH5, ICH6, ICH7, ICH8, ICH9, ICH10, SCH, PCH.
     ITE:	     IT8211F, IT8212F, IT8213F.
     JMicron:	     JMB360, JMB361, JMB363, JMB365, JMB366, JMB368.
     Marvell	     88SX5040, 88SX5041, 88SX5080, 88SX5081, 88SX6041, 88SX6042, 88SX6081, 88SX6101, 88SX6102, 88SX6111, 88SX6121, 88SX6141,
		     88SX6145, 88SX7042.
     National:	     SC1100.
     NetCell:	     NC3000, NC5000.
     nVidia:	     nForce, nForce2, nForce2 MCP, nForce3, nForce3 MCP, nForce3 Pro, nForce4, MCP51, MCP55, MCP61, MCP65, MCP67, MCP73, MCP77,
		     MCP79, MCP89.
     Promise:	     PDC20246, PDC20262, PDC20263, PDC20265, PDC20267, PDC20268, PDC20269, PDC20270, PDC20271, PDC20275, PDC20276, PDC20277,
		     PDC20318, PDC20319, PDC20371, PDC20375, PDC20376, PDC20377, PDC20378, PDC20379, PDC20571, PDC20575, PDC20579, PDC20580,
		     PDC20617, PDC20618, PDC20619, PDC20620, PDC20621, PDC20622, PDC40518, PDC40519, PDC40718, PDC40719.
     ServerWorks:    HT1000, ROSB4, CSB5, CSB6, K2, Frodo4, Frodo8.
     Silicon Image:  SiI0680, SiI3112, SiI3114, SiI3124, SiI3132, SiI3512.
     SiS:	     SIS180, SIS181, SIS182, SIS5513, SIS530, SIS540, SIS550, SIS620, SIS630, SIS630S, SIS633, SIS635, SIS730, SIS733, SIS735,
		     SIS745, SIS961, SIS962, SIS963, SIS964, SIS965.
     VIA:	     VT6410, VT6420, VT6421, VT82C586, VT82C586B, VT82C596, VT82C596B, VT82C686, VT82C686A, VT82C686B, VT8231, VT8233, VT8233A,
		     VT8233C, VT8235, VT8237, VT8237A, VT8237S, VT8251, CX700, VX800, VX855, VX900.

     Unknown ATA chipsets are supported in PIO modes, and if the standard busmaster DMA registers are present and contain valid setup, DMA is also
     enabled, although the max mode is limited to UDMA33, as it is not known what the chipset can do and how to program it.

     The ata driver can change the transfer mode and various other parameters when the system is up and running.  See atacontrol(8).

     The ata driver sets the maximum transfer mode supported by the hardware as default.  However the ata driver sometimes warns: ``DMA limited to
     UDMA33, non-ATA66 cable or device''.  This means that the ata driver has detected that the required 80 conductor cable is not present or
     could not be detected properly, or that one of the devices on the channel only accepts up to UDMA2/ATA33.	The hw.ata.ata_dma_check_80pin
     tunable can be set to 0 to disable this check.

     Unknown ATAPI devices are initialized to DMA mode if the hw.ata.atapi_dma tunable is set to 1 and they support at least UDMA33 transfers.
     Otherwise they are set to PIO mode because severe DMA problems are common even if the device capabilities indicate support.  You can always
     try to set DMA mode on an ATAPI device using atacontrol(8), but be aware that your hardware might not support it and can potentially hang the
     entire system causing data loss.

FILES

     /dev/ad*		     ATA disk device nodes
     /dev/ar*		     ATA RAID device nodes
     /dev/acd*		     ATAPI CD-ROM device nodes
     /dev/afd*		     ATAPI floppy drive device nodes
     /dev/ast*		     ATAPI tape drive device nodes
     /sys/i386/conf/GENERIC  sample generic kernel config file for ata based systems

NOTES

     Please remember that in order to use UDMA4/ATA66 and above modes you must use 80 conductor cables.  Please assure that ribbon cables are no
     longer than 45cm.	In case of rounded ATA cables, the length depends on the quality of the cables.  SATA cables can be up to 1m long accord-
     ing to the specification.

     Static device numbering (enabled with the ATA_STATIC_ID kernel option) reserves a number for each possibly connected disk, even when not
     present.  This is useful in hotswap scenarios where disks should always show up as the same numbered device, and not depend on attach order.

     Native Command Queuing (NCQ) on SATA drives is not yet supported.

SEE ALSO

     ahci(4), cam(4), ataraid(4), atacontrol(8), burncd(8), siis(4)

HISTORY

     The ata driver first appeared in FreeBSD 4.0.

AUTHORS

     Soren Schmidt <sos@FreeBSD.org>.

BSD
								   July 3, 2010 							       BSD