FreeBSD Manual Pages
ATA(4) FreeBSD Kernel Interfaces Manual ATA(4) NAME ata, acd, ad, afd, ast -- generic ATA/ATAPI disk controller driver SYNOPSIS For ISA based ATA/ATAPI support: device isa device ata0 at isa? port IO_WD1 irq 14 device ata1 at isa? port IO_WD2 irq 15 For PCI based ATA/ATAPI support: device pci device ata To support ATA compliant disk drives: device atadisk To support ATAPI CD-ROM, CDR, CDRW, DVD-ROM and DVD-RAM drives: device atapicd To support ATAPI floppy drives, such as the ZIP and LS120: device atapifd To support ATAPI tape drives: device atapist 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.atapi_dma set to 1 for DMA access, 0 for PIO (default is PIO). hw.ata.wc set to 1 to enable Write Caching, 0 to disable (default is enabled). (WARNING: might cause data loss on power failures.) hw.ata.tags set to 1 to enable Tagged Queuing support, 0 to disable (default is dis- abled). (Only IBM DPTA, DTLA, ICxxxxxxAT, ICxxxxxxAV drives support that.) DESCRIPTION This driver provides access to ATA (IDE) and SerialATA disk drives, ATAPI CD-ROM and DVD drives, ZIP drives and tape streamers connected to con- trollers according to the ATA and ATAPI standards. These devices are also commonly known as IDE or EIDE devices. The currently supported controllers with their maximum speed include: Acerlabs Aladdin Ultra DMA 100 (UDMA5), 100 MB/sec (depending on model, max stated at boot) AMD 756 Ultra DMA 66 (UDMA4), 66 MB/sec AMD 766 Ultra DMA 100 (UDMA5), 100 MB/sec CMD 646 DMA 2 (WDMA2), 16 MB/sec CMD 648 Ultra DMA 66 (UDMA4), 66 MB/sec CMD 649 Ultra DMA 100 (UDMA5), 100 MB/sec Cypress 82C693 DMA 2 (WDMA2), 16 MB/sec Cyrix 5530 Ultra DMA 33 (UDMA2), 33 MB/sec HighPoint HPT366 Ultra DMA 66 (UDMA4), 66 MB/sec HighPoint HPT370 Ultra DMA 100 (UDMA5), 100 MB/sec HighPoint HPT372 Ultra DMA 133 (UDMA6), 133 MB/sec HighPoint HPT374 Ultra DMA 133 (UDMA6), 133 MB/sec Intel PIIX DMA 2 (WDMA2), 16 MB/sec Intel PIIX3 DMA 2 (WDMA2), 16 MB/sec Intel PIIX4 Ultra DMA 33 (UDMA2), 33 MB/sec Intel ICH0 Ultra DMA 33 (UDMA2), 33 MB/sec Intel ICH Ultra DMA 66 (UDMA4), 66 MB/sec Intel ICH2 Ultra DMA 100 (UDMA5), 100 MB/sec Intel ICH3 Ultra DMA 100 (UDMA5), 100 MB/sec Intel ICH4 Ultra DMA 100 (UDMA5), 100 MB/sec Intel ICH5 SATA 150, 150 MB/sec Promise Ultra/Fasttrak-33 Ultra DMA 33 (UDMA2), 33 MB/sec Promise Ultra/Fasttrak-66 Ultra DMA 66 (UDMA4), 66 MB/sec Promise Ultra/Fasttrak-100 Ultra DMA 100 (UDMA5), 100 MB/sec Promise Ultra/Fasttrak-100 TX2/TX4 Ultra DMA 100 (UDMA5), 100 MB/sec Promise Ultra/Fasttrak-133 TX2/TX2000 Ultra DMA 133 (UDMA6), 133 MB/sec ServerWorks ROSB4 Ultra DMA 33 (UDMA2), 33 MB/sec ServerWorks CSB5 Ultra DMA 100 (UDMA5), 100 MB/sec (depending on model, max stated at boot) Sil 0680 Ultra DMA 133 (UDMA6), 133 MB/sec (depending on model, max stated at boot) SiS 5591 Ultra DMA 100 (UDMA5), 100 MB/sec (depending on model, max stated at boot) VIA 82C586 Ultra DMA 33 (UDMA2), 33 MB/sec VIA 82C596 Ultra DMA 66 (UDMA4), 66 MB/sec (depending on model, max stated at boot) VIA 82C686a Ultra DMA 66 (UDMA4), 66 MB/sec VIA 82C686b Ultra DMA 100 (UDMA5), 100 MB/sec VIA 8233/8235 Ultra DMA 133 (UDMA6), 133 MB/sec (depending on model, max stated at boot) VIA 8237 SATA 150, 150 MB/sec All unknown chipsets are supported at the maximum speed of 16 MB/sec. The ata driver also allows for changes to the transfer mode of the devices at a later time when the system is up and running, see atacontrol(8). The driver attempts to set the maximum performance transfer mode on your disk drives by selecting the highest possible DMA mode. However the ata driver sometimes issue the message "DMA limited to UDMA33, non-ATA66 cable or device", if the cable is ATA66 (or above) compliant, it is because the other device on this channel states it can only accept upto UDMA2/ATA33 signals. ATAPI devices are left in PIO mode because DMA problems are common despite the device specifications. 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 hang the system. FILES /dev/ad* ATA disk 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 Static numbering (enabled with the ATA_STATIC_ID kernel option) reserves a number for each possibly connected disk, even when not present. This may result in odd situations where, for example, ad0 and ad2 exist in the absence of ad1. The advantage is that the addition of the formerly absent drive does not cause the numbers of the other drives to change. The ata driver does not support MFM/RLL/ESDI (ST-506) style disks. Remember that in order to use UDMA4 (and above) mode you have to use a special 80 conductor cable, and the driver tries to determine if you have such a cable attached before setting UDMA4 mode. The use of UDMA4(66MHz) and higher together with non-UDMA4 devices on the same ATA channel is not recommended, unless they are run at the non-UDMA4 device's lower speed. The driver has been designed to handle that kind of setup but lots of older devices do not like this. SEE ALSO atacontrol(8), burncd(8) HISTORY The ata driver first appeared in FreeBSD 4.0. AUTHORS The ata driver was written by Soren Schmidt <sos@FreeBSD.org>. This manual page was written by Jeroen Ruigrok van der Werven <asmodai@FreeBSD.org> and Soren Schmidt <sos@FreeBSD.org>. FreeBSD 4.10 January 27, 2000 FreeBSD 4.10
NAME | SYNOPSIS | DESCRIPTION | FILES | NOTES | SEE ALSO | HISTORY | AUTHORS
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