Hi malcolm.mcdowell,
Sorry for the late reply.
We get the following information from internal:
We don’t have an i2c utility for UEFI shell but use the standard I2CMaster/I2cIO protocols for our implementation https://uefi.org/sites/default/files/resources/PI_Spec_1_7_A_final_May1.pdf (Volume 5 - Chapter 17).
For examples of this being used by drivers see
edk2-nvidia/Silicon/NVIDIA/Drivers/I2cIoBmcSsifDxe at main · NVIDIA/edk2-nvidia (github.com)
or
edk2-nvidia/Silicon/NVIDIA/Library/MaximRealTimeClockLib at main · NVIDIA/edk2-nvidia (github.com)
A utility could be written for this but we do not currently have plans for this. For examples on how to write shell utilities see something like edk2-nvidia/Silicon/NVIDIA/Application/ClockUtil at main · NVIDIA/edk2-nvidia (github.com)