[Skiboot] [RFC PATCH skiboot] npu2: Add nvlink2 interconnect information

Andrew Donnellan andrew.donnellan at au1.ibm.com
Thu Aug 16 15:38:07 AEST 2018

On 15/08/18 18:26, Alexey Kardashevskiy wrote:
> GPUs on Redbud and Sequoia platforms are interconnected between each
> other in groups of 2 or 3 GPUs. The problem with that is if we decide
> to pass one of GPUs in a group to the userspace (and potentially a guest),
> we need to make sure that interconnectd link does not get enabled.
> The GPU firmware provides a way to disable links on a GPU. However we
> want to disable only links to other GPUs which are not in the same guest
> so we need a map of what nvlink is connected to what.
> This adds an "ibm,nvlinks" property to every GPU in a "GPUn" slot
> with phandles to peer GPUs and NPU PHB, the index in the property is GPU's
> link number.
> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>

Would we be able to use a more descriptive name like 
"ibm,nvlink-peer-devices" or something?

Andrew Donnellan              OzLabs, ADL Canberra
andrew.donnellan at au1.ibm.com  IBM Australia Limited

More information about the Skiboot mailing list