CAM timeouts on Netra X1

[Chris Ross]

  This may not be sparc64 specific, but.  I have a Netra X1 that I've been netbooting, to eventually install FreeBSD onto its disks.  Booting a recent stable/9. with the old disks (one 80G, one 250G), I would see the following [sort] of errors during [net]boot:

(ada0:ata2:0:0:0): READ_DMA48. ACB: 25 00 cf cf b5 40 25 00 00 00 01 00
(ada0:ata2:0:0:0): CAM status: Command timeout
(ada0:ata2:0:0:0): Retrying command
(ada0:ata2:0:0:0): READ_DMA48. ACB: 25 00 cf cf b5 40 25 00 00 00 01 00
(ada0:ata2:0:0:0): CAM status: Command timeout
(ada0:ata2:0:0:0): Retrying command
(ada0:ata2:0:0:0): READ_DMA48. ACB: 25 00 cf cf b5 40 25 00 00 00 01 00
(ada0:ata2:0:0:0): CAM status: Command timeout
(ada0:ata2:0:0:0): Retrying command
(ada0:ata2:0:0:0): READ_DMA48. ACB: 25 00 cf cf b5 40 25 00 00 00 01 00
(ada0:ata2:0:0:0): CAM status: Command timeout
(ada0:ata2:0:0:0): Retrying command
(ada0:ata2:0:0:0): READ_DMA48. ACB: 25 00 cf cf b5 40 25 00 00 00 01 00
(ada0:ata2:0:0:0): CAM status: Command timeout
(ada0:ata2:0:0:0): Error 5, Retries exhausted

  In the past, with the old disks, it was ada1, not ada0, and that was the 250G disk that has been reporting errors when the system was running off of it (NetBSD 5.1).  So I assumed that was the problem.  However, I've replaced the disks with a pair of 320GB disks, and am now having that same problem and messages both during boot, and when trying to configure the disks with gpart, for both disks.

  Is this some sort of size issue?  And, is there any way around it?  NetBSD works on the machine, so I assume it's not that the hardware is deficient in some way with larger PATA disks...

                               - Chris