hw.ata.ata_dma="0": can I do this during bootup at the loader prompt?

[Arjan Van Leeuwen]

On Thu, 09 Dec 2004 14:24:35 +0900, Rob <spamrefuse at yahoo.com> wrote:
> 
> Hi,
> 
> In /boot/loader.conf, I have
>    hw.ata.ata_dma="0"
> to prevent a WRITE_DMA failure crash at bootup.
> Unfortunately, this forces my UDMA100 harddisk to operate
> at PIO4 speed.
> 
> There are patches flying around on this mailing list that might
> solve the problem. I'm very keen on testing such patches, but I
> should remove the line in loader.conf. However, if the patch does
> not work, I end up with an unbootable disk.
> 
> It would be nice if I can set hw.ata.ata_dma="0" at the loader
> prompt during bootup, so that the system at least will boot from
> harddisk. Is that possible?
> 

I'm not sure if I understand what you want, but you can use eg
'atacontrol mode <channel> udma33 udma33' to set your hard drive to
UDMA-33 after the system has booted.

Arjan