octeon_ep: add PF-VF mailbox communication

Implement mailbox communication between PF and VFs.
PF-VF mailbox is used for all control commands from VF to PF and
asynchronous notification messages from PF to VF.

Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

octeon_ep: control net API framework to support offloads

Inquire firmware on supported offloads, as well as convey offloads
enabled dynamically to firmware. New control net API functionality is
required for the above. Implement control net API framework for
offloads.

Additionally, fetch/insert offload metadata from hardware RX/TX
buffer respectively during receive/transmit.

Currently supported offloads include checksum and TSO.

Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Link: https://lore.kernel.org/r/20231204154940.2583140-1-srasheed@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

octeon_ep: remove atomic variable usage in Tx data path

Replace atomic variable "instr_pending" which represents number of
posted tx instructions pending completion, with host_write_idx and
flush_index variables in the xmit and completion processing respectively.

Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

octeon_ep: assert hardware structure sizes

Clean up structure defines related to hardware data to be
asserted to fixed sizes, as padding is not allowed
by hardware.

Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

octeon_ep: fix tx dma unmap len values in SG

Lengths of SG pointers are kept in the following order in
the SG entries in hardware.
63 48|47 32|31 16|15 0
-----------------------------------------
| Len 0 | Len 1 | Len 2 | Len 3 |
-----------------------------------------
| Ptr 0 |
-----------------------------------------
| Ptr 1 |
-----------------------------------------
| Ptr 2 |
-----------------------------------------
| Ptr 3 |
-----------------------------------------
Dma pointers have to be unmapped based on their
respective lengths given in this format.

Fixes: 37d79d059606 ("octeon_ep: add Tx/Rx processing and interrupt support")
Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

octeon_ep: Add driver framework and device initialization

Add driver framework and device setup and initialization for Octeon
PCI Endpoint NIC.

Add implementation to load module, initilaize, register network device,
cleanup and unload module.

Signed-off-by: Veerasenareddy Burru <vburru@marvell.com>
Signed-off-by: Abhijit Ayarekar <aayarekar@marvell.com>
Signed-off-by: Satananda Burla <sburla@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>