Problem with SATA-600 (a.k.a. SATA 3) disk

[Oliver Fromme]

I've bought a new HDD that supports SATA-600.  I've put it
into an external eSATA case and connected it to the eSATA
port of my PC.  That port supports SATA-600, too.  It is
recognized thusly:

ada2 at ahcich3 bus 0 scbus3 target 0 lun 0
ada2: <Hitachi HDS723030ALA640 MKAOA3B0> ATA-8 SATA 3.x device
ada2: 600.000MB/s transfers (SATA 3.x, UDMA6, PIO 8192bytes)
ada2: Command Queueing enabled
ada2: 2861588MB (5860533168 512 byte sectors: 16H 63S/T 16383C)

However, when trying to access the disk, I get these:

ahcich3: Timeout on slot 0
ahcich3: is 04000000 cs 00000000 ss 00000001 rs 00000001 tfd 50 serr 00480400
ahcich3: device is not ready (timeout 15000ms) tfd = 00000080
ahcich3: Timeout on slot 0
ahcich3: is 04000000 cs 00000001 ss 00000000 rs 00000001 tfd 80 serr 00080400
ahcich3: device is not ready (timeout 15000ms) tfd = 00000080
ahcich3: Timeout on slot 0
ahcich3: is 04000000 cs 00000001 ss 00000000 rs 00000001 tfd 80 serr 00080400
ahcich3: device is not ready (timeout 15000ms) tfd = 00000080
(ada2:ahcich3:0:0:0): lost device

I suspect that is because the external enclosure supports
only SATA-300 (a.k.a. SATA 2).  Both the controller and the
disk support SATA-600, so I guess that FreeBSD tries to use
SATA-600, which fails because the external case doesn't
support that.

Is there a way to force FreeBSD to use SATA-300 only?
I've searched the mailing lists, but without results.

Best regards
   Oliver

-- 
Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606,  Geschäftsfuehrung:
secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün-
chen, HRB 125758,  Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart

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