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Merge branch 'qed-vf-xdp'
Yuval Mintz says:
qed*: Support VF XDP attachment
====================
Each driver queue [Rx, Tx, XDP-forwarding] requires an allocated HW/FW
connection + configured queue-zone.
VF handling by the PF has several limitations that prevented adding the
capability to perform XDP at driver-level:
- The VF assumes there's 1-to-1 correspondance between the VF queue and
the used connection, meaning q<x> is always going to use cid<x>,
whereas for its own queues the PF is acquiring a new cid per each new
queue.
- There's a 1-to-1 correspondate between the VF-queues and the HW queue
zones. While this is necessary for Rx-queues [as the queue-zone
contains the producer], transmission queues can share the underlaying
queue-zone [only shared configuration is coalescing].
But all VF<->PF communication mechanisms assume there's a single
identifier that identify a queue [as queue-zone == queue], while
sharing queue-zones requires passing additional information.
- VFs currently don't try mapping a doorbell bar - there's a small
doorbell window in the regview allowing VFs to doorbell up to 16
connections; but this window isn's wide enough for the added XDP
forwarding queues.
This series is going to add the necessary infrastrucutre to finally let
our VFs support XDP assuming both the PF and VF drivers are sufficiently
new [Legacy support would be retained both for older VFs and older PFs,
but both will be needed for this new support to work].
Basically, the various database driver maintains for its queue-cids
would be revised, and queue-cids would be identified using the
(queue-zone, unique index) pair. The TLV mechanism would then be
extended to allow VFs to communicate that unique-index as well as the
already provided queue-zone. Finally, the VFs would try to map their
doorbell bar and inform their PF that they're using it.
Almost all the changes are in qed, with exception of #3 [which does some
cleanup in qede as well] and #11 that actually enables the feature.
====================
Signed-off-by: 
David S. Miller <davem@davemloft.net>