On 2008-05-13, Daniel Polak <daniel@sys.nl> wrote:
quoted text
> I have a system with an IDE hard disk and CF-IDE adapter.
> The CF-IDE adapter works fine with CF cards of 512 MB capacity and less.
> As time goes by smaller capacity cards become more difficult to find so 
> I bought several 1 GB Kingston CF cards.
>
> However these CF cards don't seem to work (on OpenBSD 4.3 stable). I 
> tried three empty 1 GB Kingston CF cards and they all prevent the system 
> from getting past loading the kernel.
> I went back to a smaller card and then everything is fine.
>
> The error message is
> type: ata
> c_bcount: 512
> c_skip: 0
> pciide0:1:0: bus-master DMA error: missing interrupt, status=0x21

Your card supports DMAs, but your adapter doesn't wire the required line.
This was a later addition to the CF spec, you can disable DMA with flags
to wd(4).

See http://lists.soekris.com/pipermail/soekris-tech/2007-May/012083.html