commit 5b5656565ba4046f7d7fdc61d9fc79a1f67993be
author marxwang <marx.wang@intel.com> Tue Sep 11 12:08:23 2018 +0800
committer Martin Roth <martinroth@google.com> Fri Sep 21 14:30:52 2018 +0000
tree fddb6f6e5e3969c1f5a48deda8a027e02ccdea89
parent eaca95eaf4cf074818e8e1bfa18f0b137143cc89

mb/google/poppy/variants/rammus: Disable command TriState for rammus

This patch sets the MRC UPD "CmdTriStateDis" to disable TriState for
the rammus boards. Rammus is LPDDR3 design without RTT for CMD/CTRL.

BUG=none
TEST=Run memtester app and also webgl fishtank on the LPDDR3 kabylake
     boards and also check the margin data is proper in FSP.

Change-Id: Iee115f49ba5b36dc5b0425e9da02b58cd19b2236
Signed-off-by: Marx Wang <marx.wang@intel.com>
Reviewed-on: https://review.coreboot.org/28568
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/poppy/variants/rammus/devicetree.cb

diff --git a/src/mainboard/google/poppy/variants/rammus/devicetree.cb b/src/mainboard/google/poppy/variants/rammus/devicetree.cb
index 3478744..7b851ac 100644
--- a/src/mainboard/google/poppy/variants/rammus/devicetree.cb
+++ b/src/mainboard/google/poppy/variants/rammus/devicetree.cb
@@ -27,6 +27,9 @@
 	# Enable S0ix
 	register "s0ix_enable" = "1"
 
+	# Disable Command TriState
+	register "CmdTriStateDis" = "1"
+
 	# FSP Configuration
 	register "ProbelessTrace" = "0"
 	register "EnableLan" = "0"