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Diffstat (limited to 'roms/skiboot/doc/device-tree/memory-hierarchy.rst')
| -rw-r--r-- | roms/skiboot/doc/device-tree/memory-hierarchy.rst | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/roms/skiboot/doc/device-tree/memory-hierarchy.rst b/roms/skiboot/doc/device-tree/memory-hierarchy.rst new file mode 100644 index 000000000..c3c1d0349 --- /dev/null +++ b/roms/skiboot/doc/device-tree/memory-hierarchy.rst @@ -0,0 +1,26 @@ +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 */ + }; + |