atapicam troubles - pc doesn't boot (sometimes)

[Stefan Ehmann]

Since latest cvsup kernel doesn't boot about half of the time. Without
ATAPICAM it just boots fine every time.

verbose logging hangs after

GEOM: Configure ad1s1, start 32256 length 40015954944 end 40015987199
(probe0:ata0:0:0:0): error 22
(probe0:ata0:0:0:0): Unretryable Error
(probe0:ata0:0:0:0): error 22
(probe0:ata0:0:0:0): Unretryable Error
(probe1:ata0:0:1:0): error 22
(probe1:ata0:0:1:0): Unretryable Error
(probe1:ata0:0:1:0): error 22
(probe1:ata0:0:1:0): Unretryable Error

Full dmesg of a successful boot can be found here:
http://stud4.tuwien.ac.at/~e0125637/fbsd/dmesg

I don't know if this is related but the order of probing seems to
indeterministic. The dmesg in the link above has the same order as shown
in the error case. If you look at dmesg2 probe2 comes first.