nb/intel/sandybridge: support more XMP timings

Tested with a pair of GSkill F3-1866C9-8GSR.

This makes sure in particular that we honor the CMD rate requested by
the XMP profile. This memory kit needs a CMD rate of 2 to be stable at
DDR3-1600 and up, even though it passes training at 1.

Also respect requested CWL to match vendor firmware and for a potential
increase in performance. The tested kit requests a tighter value than
the per-frequency table provides and has shown to be stable using that
setting.

Change-Id: I634bed764d76345c27f02a2fae5abb2d81b38fd9
Signed-off-by: Dan Elkouby <streetwalkermc@gmail.com>
Reviewed-on: https://review.coreboot.org/25664
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions