From owner-freebsd-hackers@FreeBSD.ORG  Tue Aug 10 22:50:14 2010
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In-reply-to: Your message of "Tue, 10 Aug 2010 23:08:41 +0200."
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	message dated "Tue, 10 Aug 2010 23:08:41 +0200."
Date: Tue, 10 Aug 2010 15:50:12 -0700
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20100810225012.A8CE35B67@mail.bitblocks.com>
Cc: geom@freebsd.org, hackers@freebsd.org
Subject: Re: Support for WD Advanced Format disks 
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After poking around some, it seems ATA/ATAPI-7 Identify
Device word 106 bit 13 is set to 1 and bits 0-3 are set to 3
(for 2^3 or 8 LBAs per sector) for a 4KB sector size (pin 7-8
jumper on a WD AF disks presumably changes this setting to
0,0).  See page 121 of Atapi-7 volume 1 (google for
ata-atapi-7.pdf).

Hopefully this helps in whatever `clean solution' you are
looking for?