Re: How to disable DMA for compact-flash disk?

From: Ben Greear
Date: Fri Aug 14 2009 - 17:18:21 EST


On 08/14/2009 02:10 PM, Alan Cox wrote:
This worked fine, but now I'm having some more issues. Using libata is 1/2
as fast as using IDE mode. I *think* the problem might be that libsata
may not be using 32-bit PIO mode, but I'm not certain of that. It seems
that ide mode uses PIO2 v/s PIO4 for libsata too.

As of 2.6.29 libata doesn't use 32bit PIO (it shouldn't make a difference
for most chipsets but it does for some). 2.6.30 does for some and you can
turn it on for others if you want to test by inheriting
ata_bmdma32_port_ops instead of ata_bmdma_port_ops

Can you give me a clue as to what code needs poking? I'm working
on the latest 31-rc5 tree, btw.


PS. Can't get an ide based 2.6.31-rc5 kernel to boot in F11, though it doesn't seem
to be related to ide. I probably have something wrong in my .config.

Thanks,
ben

--
Ben Greear <greearb@xxxxxxxxxxxxxxx>
Candela Technologies Inc http://www.candelatech.com

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