freebsd-nq/share/man/man4/ata.4

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.Dd November 4, 2003
.Dt ATA 4
.Os
.Sh NAME
.Nm ata ,
.Nm ar ,
.Nm acd ,
.Nm ad ,
.Nm afd ,
.Nm ast
.Nd generic ATA/ATAPI disk controller driver
.Sh SYNOPSIS
For ISA based ATA/ATAPI support:
.Cd device isa
.Cd device ata
.Pp
In
.Pa /boot/device.hints :
.Cd hint.ata.0.at="isa"
.Cd hint.ata.0.port="0x1f0"
.Cd hint.ata.0.irq="14"
.Cd hint.ata.1.at="isa"
.Cd hint.ata.1.port="0x170"
.Cd hint.ata.1.irq="15"
.Pp
For PC98 based ATA/ATAPI support:
.Cd device isa
.Cd device ata
.Pp
In
.Pa /boot/device.hints :
.Cd hint.atacbus.0.at="isa"
.Cd hint.atacbus.0.port="0x640"
.Cd hint.atacbus.0.irq="9"
.Pp
For PCI based ATA/ATAPI support:
.Cd device pci
.Cd device ata
.Pp
To support ATA compliant disk drives:
.Cd device atadisk
.Pp
To support ATA software RAID's:
.Cd device ataraid
.Pp
To support ATAPI CDROM, DVD and CD/DVD burner drives:
.Cd device atapicd
.Pp
To support ATAPI floppy drives:
.Cd device atapifd
.Pp
To support ATAPI tape drives:
.Cd device atapist
.Pp
The following tunables are settable from the loader:
.Bl -ohang
.It Va hw.ata.ata_dma
set to 1 for DMA access, 0 for PIO (default is DMA).
.It Va hw.ata.atapi_dma
set to 1 for DMA access, 0 for PIO (default is PIO).
.It Va hw.ata.wc
set to 1 to enable Write Caching, 0 to disable (default is enabled).
.Em WARNING :
can cause data loss on power failures.
.El
.Sh DESCRIPTION
The
.Nm
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. 
.Pp
The currently supported ATA/SATA controller chips are:
.Pp
.Bl -tag -width "Silicon Image:" -compact
.It Acard:
ATP850P, ATP860A, ATP860R, ATP865A, ATP865R
.It ALI:
Aladdin (ALi5229) compatible chips.
.It AMD:
AMD756, AMD766, AMD768, AMD8111.
.It CMD:
CMD646, CMD648, CMD649.
.It Cypress:
Cypress 82C693.
.It Cyrix:
Cyrix 5530.
.It HighPoint:
HPT302, HPT366, HPT366, HPT368, HPT370, HPT371, HPT372, HPT374.
.It Intel:
PIIX, PIIX3, PIIX4, ICH, ICH0, ICH2, ICH3, ICH4, ICH5.
.It National:
SC1100.
.It nVidia:
nForce, nForce2, nForce3.
.It Promise:
PDC20246, PDC20262, PDC20263, PDC20265, PDC20267, PDC20268, PDC20269, PDC20270, PDC20271, PDC20275, PDC20276, PDC20277, PDC20318, PDC20319, PDC20371, PDC20375, PDC20376, PDC20377, PDC20378, PDC20379, PDC20617, PDC20618, PDC20619, PDC20620.
.It ServerWorks:
ROSB4, CSB5, CSB6.
.It Silicon Image:
SiI0680, SiI3112, SiI3114, SiI3512.
.It SiS:
SIS5513, SIS530, SIS540, SIS550, SIS620, SIS630, SIS630S, SIS633, SIS635, SIS730, SIS733, SIS735, SIS745, SIS961, SIS962, SIS963, SIS964
.It VIA:
VT82C586, VT82C586B, VT82C596, VT82C596B, VT82C686, VT82C686A, VT82C686B, VT8231, VT8233, VT8233A, VT8233C, VT8235, VT8237.
.El
.Pp
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 limitted to UDMA33, as it is
not known what the chipset can do and how to program it.
.Pp
The
.Nm
driver can change the transfer mode and various other parameters
when the system is up and running.
See
.Xr atacontrol 8 .
.Pp
The
.nm
driver sets the maximum transfer mode supported by the hardware as default.
However the
.Nm
driver sometimes warns:
.Dq Sy "DMA limited to UDMA33, non-ATA66 cable or device".
This means that
the
.Nm
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.
.Pp
ATAPI devices are set to PIO mode by default 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
.Xr atacontrol 8 ,
but be aware that your hardware might
.Em not
support it and can potentially
.Em hang
the entire system causing data loss.
.Sh FILES
.Bl -tag -width ".Pa /sys/i386/conf/GENERIC" -compact
.It Pa /dev/ad*
ATA disk device nodes
.It Pa /dev/ar*
ATA RAID device nodes
.It Pa /dev/acd*
ATAPI CD-ROM device nodes
.It Pa /dev/afd*
ATAPI floppy drive device nodes
.It Pa /dev/ast*
ATAPI tape drive device nodes
.It Pa /sys/i386/conf/GENERIC
sample generic kernel config file for
.Nm
based systems
.El
.Sh NOTES
Please remember that in order to use UDMA4/ATA66 and above modes you
.Em 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 according to the specification.
.Pp
Static device numbering
(enabled with the
.Dv ATA_STATIC_ID
kernel option)
reserves a number for each possibly connected disk,
even when not present.
This is useful in hotswap senarios
where disks should always show up as the same numbered device,
and not depend on attach order.
.Pp
.Sh SEE ALSO
.Xr atacontrol 8 ,
.Xr burncd 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 4.0 .
.Sh AUTHORS
.An S\(/oren Schmidt
.Aq sos@FreeBSD.org .