Re: [PATCH 0/7] Switchtec NTB Crosslink Support

[Logan Gunthorpe]

Also, I forgot to mention, this patch set is based on today's ntb-next.

Logan

On 29/11/17 10:55 AM, Logan Gunthorpe wrote:
> Hi,
>
> This patch series adds support for the Switchtec Crosslink feature.
> Crosslink is similar to B2B in that it allows two switches to be
> connected back to back.
>
> Two switches can already be connected between two hosts, however with this
> setup, there would be no symmetry as one switch would handle NTB and the
> other would just need to be a single partition switch. Our customers are
> looking for a completely symmetric solution such that a host or switch
> can be easily replaced without needing to worry about which half was
> replaced.
>
> Crosslink solves this problem by having each of the switches configured
> with two partitions. This results in a special host-less partition in
> the middle of the connection which can be managed in such a way as
> to forward all the traffic and still provide all the same NTB
> functionality. In this way, both hosts and switches can be identical.
>
> Please see Patch 6 for a bit more detailed description of how Crosslink
> works.
>
> Thanks,
>
> Logan
>
> Kelvin Cao (1):
>    ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups
>
> Logan Gunthorpe (6):
>    ntb_hw_switchtec: Keep track of the number of LUT windows used by the
>      driver
>    ntb_hw_switchtec: Create helper function to setup reserved LUT MWs
>    ntb_hw_switchtec: Make switchtec_ntb_init_req_id_table() more general
>    ntb_hw_switchtec: Expand PFF CSR registers
>    ntb_hw_switchtec: Add initialization code for crosslink
>    ntb_hw_switchtec: Crosslink doorbells and messages
>
>   drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 494 +++++++++++++++++++++++++++------
>   include/linux/ntb.h                    |  15 +-
>   include/linux/switchtec.h              |  23 +-
>   3 files changed, 435 insertions(+), 97 deletions(-)
>
> --
> 2.11.0