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+P9 memory hierarchy
+-------------------
+P9 Nimbus supports direct attached DDR memory through 4 DDR ports per side
+of the processor. Device tree contains memory hierarchy so that one can
+traverse from chip to DIMM like below:
+
+  xscom@<addr>/mcbist@<mcbist_id>/mcs@<mcs_id>/mca@<mca_id>/dimm@<resource_id>
+
+Example of dimm node:
+.. code-block:: dts
+
+  dimm@d00e {
+          memory-id = <0xc>; /* DRAM Device Type. 0xc = DDR4 */
+          product-version = <0x32>; /* Module Revision Code */
+          device_type = "memory-dimm-ddr4";
+          serial-number = <0x15d9ad1c>;
+          status = "okay";
+          size = <0x4000>;
+          phandle = <0xd2>;
+          ibm,loc-code = "UOPWR.0000000-Node0-DIMM14";
+          part-number = "36ASF2G72PZ-2G6B2   ";
+          reg = <0xd00e>;
+          manufacturer-id = <0x802c>; /* Vendor ID, we can get vendor name from this ID */
+  };