Re: PCI probing problem

mlord (mlord@pobox.com)
Wed, 28 Jan 1998 19:21:10 -0500

Zlatko Calusic wrote:
>
> kernel@dotd.dyn.ml.org writes:
>
> > Upon boot of a 2.1.80 kernel (egcs 1.0.1) I get the following:
> >
> > PCI_IDE: unknown IDE controller on PCI bus 0 function 88, VID=10b9, DID=5229
> > PCI_IDE: not 100% native mode: will probe irqs later
> > PCI_IDE: simplex device: DMA disabled
> > ide0: PCI_IDE Bus-Master DMA disabled (BIOS), pcicmd=0x0005, ccode=0x101fa20, dma_base=0x0000
> > PCI_IDE: simplex device: DMA disabled
> > ide1: PCI_IDE Bus-Master DMA disabled (BIOS), pcicmd=0x0005, ccode=0x101fa20, dma_base=0x0000

The problem here is that this IDE interface claims to be "simplex only",
meaning that DMA can only be used on a single channel at a time.

As that is kind of oddball in the modern world, and also somewhat tricky
to manage correctly, Linux IDE just plain refuses to do DMA on simplex
chipsets. It tries to configure this one, but gives up when it sees
the
simplex flag.
\

-- 
mlord@pobox.com
The Linux IDE guy