More info on IDE lockup after APM restore

[Jeremy Fitzhardinge]

Earlier I reported that after an APM restore from disk, the HD locks
up (light solid on) on the first access; after a while it reports:
hda: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14

I found that disabling CONFIG_PIIX_TUNING fixes this, and it can save and
restore without problems.

What does PIIX_TUNING do, and should I expect it to work for me?
My setup is a Sharp Actius A-100 laptop running 2.3.99pre5.

        J