two ata problems

[Richard Nyberg]

I experience two problems with ata at boot.

1) Long pause followed by the warning below.

2) ad2 is set to UDMA100 even though it should be limited
   to UDMA33 because of the old cable. This causes a fallback to PIO.
   I can run it in UDMA33 later by setting it with atacontrol.

excerpt from dmesg:
ad0: 57241MB <ST360021A> [116301/16/63] at ata0-master UDMA100
ad2: 29314MB <IBM-DTLA-307030> [59560/16/63] at ata1-master UDMA100
ata1-slave: DMA limited to UDMA33, non-ATA66 cable or device
acd0: CD-RW <LITE-ON COMBO LTC-48161H> at ata1-slave UDMA33
**WARNING** waiting for the following device to finish configuring:
  xpt:  func=0xc0137161 arg=0
Mounting root from ufs:/dev/ad2s2a
cd0 at ata1 bus 0 target 1 lun 0
cd0: <LITE-ON COMBO LTC-48161H KH0P> Removable CD-ROM SCSI-0 device 
cd0: 33.000MB/s transfers
cd0: cd present [336745 x 2048 byte records]
ad2: UDMA ICRC error reading fsbn 0 (ad2 bn 0; cn 0 tn 0 sn 0) retrying
ad2: UDMA ICRC error reading fsbn 0 (ad2 bn 0; cn 0 tn 0 sn 0) retrying
ad2: UDMA ICRC error reading fsbn 0 (ad2 bn 0; cn 0 tn 0 sn 0) retrying
ad2: UDMA ICRC error reading fsbn 0 (ad2 bn 0; cn 0 tn 0 sn 0) falling back to PIO mode

        -Richard