Each user port of the NETC switch supports 802.3 basic and mandatory
managed objects statistic counters and IETF Management Information
Database (MIB) package (RFC2665) and Remote Network Monitoring (RMON)
counters. And all of these counters are 64-bit registers. In addition,
some user ports support preemption, so these ports have two MACs, MAC
0 is the express MAC (eMAC), MAC 1 is the preemptible MAC (pMAC). So
for ports that support preemption, the statistics are the sum of the
pMAC and eMAC statistics.

Note that the current switch driver does not support preemption, all
frames are sent and received via the eMAC by default. The statistics
read from the pMAC should be zero.

Signed-off-by: Wei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20260518082506.1318236-15-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

For i.MX94 series, the NETC IP provides full 802.1Q Ethernet switch
functionality, advanced QoS with 8 traffic classes, and a full range of
TSN standards capabilities. The switch has 3 user ports and 1 CPU port,
the CPU port is connected to an internal ENETC. Since the switch and the
internal ENETC are fully integrated within the NETC IP, no back-to-back
MAC connection is required. Instead, a light-weight "pseudo MAC" is used
between the switch and the ENETC. This translates to lower power (less
logic and memory) and lower delay (as there is no serialization delay
across this link).

Introduce the initial NETC switch driver with basic probe and remove
functionality. More features will be added in subsequent patches.

Signed-off-by: Wei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20260518082506.1318236-11-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>