On some but not all devices using the RTL8221B 2.5GBit/s PHY the SerDes
setup sequence may hang under some circumstances (eg. <2500M link
partner present during boot).
RTL8221B-VB-CG 2.5Gbps PHY (C45) mdio-bus:01: rtl822xb_config_init failed: -110
Work-around the issue by performing a hardware reset and subsequent
retry of the SerDes setup, which seems to always succeed.
Doing this requires moving ALDPS setup to config_init (which is anyway
the better place for that) as it otherwise doesn't survive the reset.
Also disable listening on MDIO address 0 which may be used by other PHYs
despite being spec'ed as "broadcast address", as bus activity on address
0 may otherwise confuse the RealTek PHY for good reasons.
Tested-by: Luis Mita <luis@luismita.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Follow the advise of Russell King allows to greatly improve the driver
for RealTek's 1G and 2.5G Ethernet PHYs. The results are full/half
duplex as well as Gbit master/slave property being read from PHY
Specific Status Register (PHYSR), and fixes regarding link-partner
advertisement.
Fixes: #14504
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
