User:Meklort/SORDIMM

Enabling SO-DOMM modules on the Talos II

The Talos II supports a large number of full sized DIMMs, however, in order to check the feasibility of a smaller form factor (read: laptop), the hardware and firmware need to be able to support SO-DIMMs.

Hardware Requirements

The Sofra POWER9 CPU requires registered DDR4 RAM with EC. This is relatively easy to find in the full-sized form factor, however it becomes a bit harder to find in the SO-DIMM form factor. In this case, we actually need to use SORDIMMs (note the extra R for registered).

After contacting a number of vendors, I received a response from Viking Technology where they were willing to send 10x 16GB, 2666MHz SORDIMM to Digikey so that I could purchase a few sticks: https://www.digikey.com/products/en?keywords=VR9FR2G7228JBKSBD4

Datasheet: https://media.digikey.com/pdf/Data%20Sheets/Viking%20PDFs/PS9FRxx72x8xxx_Rev.E_3_7_2018_DS.pdf

In order to adapt the above modules to the full sized slot, something like the following can be used: https://www.amazon.com/gp/product/B07DMNH15W/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Software Requirements

Before SORDIMM modules can be used, a couple of minor patches to the hostboot firmware must be made. The first patch is simply enabling hostboot to recognize that SORDIMM modules are valid.

File:0001-Update-hostboot-to-allow-DDR4-SORDIMM-modules-to-be- (1).patch

Additionally, the Talos II firmware (as of 1.07) was unable to properly detect the manufacturer ID from the modules. As a quick test, I modified the hostboot firmware to treat a manufacturer id of 0 as Samsung. Once done, the RAM was detected and booted without issues.