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authorAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
committerAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
commitaf1a266670d040d2f4083ff309d732d648afba2a (patch)
tree2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/skiboot/doc/device-tree/memory-hierarchy.rst
parente02cda008591317b1625707ff8e115a4841aa889 (diff)
Add submodule dependency filesHEADmaster
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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 */
+ };
+