[Skiboot] [PATCH 2/2] npu2-hw-procedures.c: Correct phy lane mapping

Reza Arbab arbab at linux.vnet.ibm.com
Thu Jan 25 04:26:44 AEDT 2018


On Wed, Jan 24, 2018 at 02:44:58PM +1100, Alistair Popple wrote:
>Each nvlink device is associated with a particular group of OBUS lanes via
>a lane mask which is read from HDAT via the device-tree. However Skiboot's
>interpretation of lane mask was different to what is exported from the
>HDAT.
>
>Specifically the lane mask bits in the HDAT are encoded in IBM bit ordering
>for a 24-bit wide value. So for example in normal bit ordering lane-0 is
>represented by having lane-mask bit 23 set and lane-23 is represented by
>lane-mask bit 0. This patch alters the Skiboot interpretation to match what
>is passed from HDAT.

Reviewed-by: Reza Arbab <arbab at linux.vnet.ibm.com>

-- 
Reza Arbab



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