How to disable UDMA for HDD?

[Stevan Tiefert]

On Monday 09 August 2004 17:13, Nathan Kinkade wrote:
> On Mon, Aug 09, 2004 at 11:10:40AM +0200, Stevan Tiefert wrote:
> > Hello,
> >
> > when I try to install FreeBSD 5.2.1 on my computer with HDD on
> > ata0-master and CD-ROM on ata0-slave I got five interessting messages
> > during the boot-process:
> >
> > ...
> > ad0: 4124MB <SAMSUNG VA34323A> [8938/15/63] at ata0-master UDMA33
> > ad0: TIMEOUT - READ_DMA retrying (2 retries left) LBA=8446347
> > ad0: TIMEOUT - READ_DMA retrying (2 retries left) LBA=0
> > ad0: WARNING - READ_DMA interrupt was seen but timeout fired LBA=8446347
> > ad0: WARNING - READ_DMA interrupt was seen but taskqueue stalled
> > LBA=8446347
> >
> > then the computer stops and he resists in this state till now...
> > OpenBSD "downgrades" this DMA-thing automaticly and the CD-ROM seems not
> > supporting UDMA and I assume to set at bootphase 3 a device.hint but I
> > don't know which one?
> >
> > With regards
> > Mr.
> > Stevan Tiefert
>
> Here are the two pertinent sysctl variables for your ATA hard disk and
> CDROM, respectively:
>
> hw.ata.ata_dma: 1
> hw.ata.atapi_dma: 0
>
> These variables are read only once the kernel has been booted, so if you
> want to try setting them manually you'll have to put them into
> /boot/loader.conf as something like:
>
> hw.ata.ata_dma=0
>
> Nathan

Hello Nathan,

your tip was useful, but I "corrected" it:

set hw.ata.ata_dma="0"

Now it is possible to install FreeBSD!

Thanks very much!
Mr.
Stevan Tiefert

-- 
deltree /y c:\windows
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