derate NVLINK frequency for Nimbus DD1

  limit to 20gbs

Change-Id: Idb20b4c344002ebfd775bd82e0b3f0337a69b626
Original-Change-Id: Ie348a42f0a0c305012dc91453d384b18459a0545
CQ: SW387041
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/39616
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Reviewed-by: Thi N. Tran <thi@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Tested-by: PPE CI <ppe-ci+hostboot@us.ibm.com>
Reviewed-by: Matt K. Light <mklight@us.ibm.com>
Reviewed-by: Prachi Gupta <pragupta@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>

src/import/chips/p9/procedures/xml/attribute_info/chip_ec_attributes.xml

@@ -1899,6 +1899,23 @@
     </chipEcFeature>
   </attribute>
   <!-- ******************************************************************** -->
+  <attribute>
+    <id>ATTR_CHIP_EC_FEATURE_SW387041</id>
+    <targetType>TARGET_TYPE_PROC_CHIP</targetType>
+    <description>
+      DD1 only: restrict NVLINK frequency to 20gbs
+    </description>
+    <chipEcFeature>
+      <chip>
+        <name>ENUM_ATTR_NAME_NIMBUS</name>
+        <ec>
+          <value>0x20</value>
+          <test>LESS_THAN</test>
+        </ec>
+      </chip>
+    </chipEcFeature>
+  </attribute>
+  <!-- ******************************************************************** -->
   <attribute>
     <id>ATTR_CHIP_EC_FEATURE_HW396230_SCAN_ONLY</id>
     <targetType>TARGET_TYPE_PROC_CHIP</targetType>