Call for testers: Apple ATA DMA

[Marcel Moolenaar]

On Sep 23, 2008, at 10:54 AM, Nathan Whitehorn wrote:

> Marcel Moolenaar wrote:
*snip*
>>>> Interesting. My G4 Mac Mini 1.5Ghz is hanging hard:
>>>>   :
>>>> ad0: 76319MB <Seagate ST9808211A 3.07> at ata1-master UDMA100
>>>> acd0: DVDR <MATSHITACD-RW CW-8124/DACD> at ata1-slave UDMA33
>>>>   *hang*
>>>> Could be related...
*snip*
> Ways to check if this is the problem:
> 1) Limit devices to UDMA33.
> 2) Disable DMA on acd0.


I finally got some time to play around with it:

o  When I set hw.ata.ata_dma=0 & hw.ata.atapi_dma=0 at
    the loader prompt and boot, everything is fine and
    working in PIO4.
o  I can use atacontrol and change the mode of ad0 to
    udma4/udma66.
o  I can use atacontrol and change the mode of acd0 to
    udma2/udma33.
o  I can then change the mode of ad0 to udma5/udma100.

Apparently udma100+udma33 can work, just not when it's
configured automatically or directly...

Could it make a difference if we first configure pio4
before we switch to udma?

-- 
Marcel Moolenaar
xcllnt at mac.com