Any objections/comments on axing out old ATA stack?

Ian Lepore ian at
Thu Mar 28 14:00:56 UTC 2013

On Thu, 2013-03-28 at 09:17 +0200, Alexander Motin wrote:
> On 28.03.2013 02:43, Adrian Chadd wrote:
> > My main concern with the new stuff is that it requires CAM and that's
> > reasonably big compared to the standalone ATA code.
> >
> > It'd be nice if we could slim down the CAM stack a bit first; it makes
> > embedding it on the smaller devices really freaking painful.
> Are there many boards now with ATA, but without USB? But I agree, it 
> should be checked.

It's not necessarily what the boards have but how they're used.  We use
industrial SBCs at work that have ata compact flash sockets on the board
which we do use, and usb interfaces which we don't use.

I've never tested the new ata+cam stuff on some of these boards, most
based on Cyrix, Via, Geode, and VortexD86 chipsets.  The older ata code
works, but not always very well -- for example, we usually have to set
hw.ata.ata_dma=0 for absolutely no reason we've ever been able to figure
out except that if we leave it enabled we get DMA errors and panics on
some CF cards and not on others.  I have no idea whether to expect such
things to be better, worse, or no different by changing to the ata+cam
way of doing things (but I don't really have time to do extensive
testing right now either).

-- Ian

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