Merge branch 'net-ethernet-mtk_eth_soc-add-basic-support-for-mt7988-soc'

Daniel Golle says:

====================
net: ethernet: mtk_eth_soc: add basic support for MT7988 SoC

The MediaTek MT7988 SoC introduces a new version (3) of the NETSYS
block and comes with three instead of two MACs.

The first MAC can be internally connected to a built-in Gigabit
Ethernet switch with four 1000M/100M/10M twisted pair user ports.

The second MAC can be internally connected to a built-in 2500Base-T
Ethernet PHY.

There are two SerDes units which can be operated in USXGMII, 10GBase-(K)R,
5GBase-R, 2500Base-X, 1000Base-X or SGMII interface mode.

This series adds initial support for NETSYS v3 and the first MAC of the
MT7988 SoC connecting the built-in DSA switch.

The switch is supported since commit 110c18bf ("net: dsa: mt7530:
introduce driver for MT7988 built-in switch").

Basic support for the 1000M/100M/10M built-in PHYs connected to the
switch ports is present since commit ("98c485ea

 net: phy: add
driver for MediaTek SoC built-in GE PHYs").
====================

Link: https://lore.kernel.org/r/cover.1690246066.git.daniel@makrotopia.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>