treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/ncsi: Add generic netlink family

Add a generic netlink family for NCSI. This supports three commands;
NCSI_CMD_PKG_INFO which returns information on packages and their
associated channels, NCSI_CMD_SET_INTERFACE which allows a specific
package or package/channel combination to be set as the preferred
choice, and NCSI_CMD_CLEAR_INTERFACE which clears any preferred setting.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ncsi: NCSI AEN packet handler

This introduces NCSI AEN packet handlers that result in (A) the
currently active channel is reconfigured; (B) Currently active
channel is deconfigured and disabled, another channel is chosen
as active one and configured. Case (B) won't happen if hardware
arbitration has been enabled, the channel that was in active
state is suspended simply.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ncsi: NCSI response packet handler

The NCSI response packets are sent to MC (Management Controller)
from the remote end. They are responses of NCSI command packets
for multiple purposes: completion status of NCSI command packets,
return NCSI channel's capability or configuration etc.

This defines struct to represent NCSI response packets and introduces
function ncsi_rcv_rsp() which will be used to receive NCSI response
packets and parse them.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ncsi: NCSI command packet handler

The NCSI command packets are sent from MC (Management Controller)
to remote end. They are used for multiple purposes: probe existing
NCSI package/channel, retrieve NCSI channel's capability, configure
NCSI channel etc.

This defines struct to represent NCSI command packets and introduces
function ncsi_xmit_cmd(), which will be used to transmit NCSI command
packet according to the request. The request is represented by struct
ncsi_cmd_arg.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ncsi: Resource management

NCSI spec (DSP0222) defines several objects: package, channel, mode,
filter, version and statistics etc. This introduces the data structs
to represent those objects and implement functions to manage them.
Also, this introduces CONFIG_NET_NCSI for the newly implemented NCSI
stack.

* The user (e.g. netdev driver) dereference NCSI device by
"struct ncsi_dev", which is embedded to "struct ncsi_dev_priv".
The later one is used by NCSI stack internally.
* Every NCSI device can have multiple packages simultaneously, up
to 8 packages. It's represented by "struct ncsi_package" and
identified by 3-bits ID.
* Every NCSI package can have multiple channels, up to 32. It's
represented by "struct ncsi_channel" and identified by 5-bits ID.
* Every NCSI channel has version, statistics, various modes and
filters. They are represented by "struct ncsi_channel_version",
"struct ncsi_channel_stats", "struct ncsi_channel_mode" and
"struct ncsi_channel_filter" separately.
* Apart from AEN (Asynchronous Event Notification), the NCSI stack
works in terms of command and response. This introduces "struct
ncsi_req" to represent a complete NCSI transaction made of NCSI
request and response.

link: https://www.dmtf.org/sites/default/files/standards/documents/DSP0222_1.1.0.pdf
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>