Re: pata_amd dropping to PIO on resume

From: Robert Hancock
Date: Fri Feb 16 2007 - 18:20:50 EST

Tobias Diedrich wrote:
Possibly a known issue:

After resume pata_amd drops from UDMA/33 to PIO on my system.
Reloading the module puts both attached optical drives (master and
slave) back to UDMA/33.

AFAICS "simplex DMA is claimed by other device, disabling DMA" seems
to be causing it to drop to PIO (but only after a suspend/resume
cycle, not on boot or module load).

Burning a DVD with 6x speed using PIO makes heavy use of burnproof
and makes the whole system quite sluggish. :)

Yes, the fact that it's going into simplex mode is the problem, it wasn't in simplex to start with. It looks like pata_amd does an ata_pci_clear_simplex only for certain chip models, maybe this model needs it as well?

Robert Hancock Saskatoon, SK, Canada
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