Madalin Bucur says:
====================
net: fsl/fman: address erratum
A011043
This addresses a HW erratum on some QorIQ DPAA devices.
MDIO reads to internal PCS registers may result in having
the MDIO_CFG[MDIO_RD_ER] bit set, even when there is no
error and read data (MDIO_DATA[MDIO_DATA]) is correct.
Software may get false read error when reading internal
PCS registers through MDIO. As a workaround, all internal
MDIO accesses should ignore the MDIO_CFG[MDIO_RD_ER] bit.
When the issue was present, one could see such errors
during boot:
mdio_bus
ffe4e5000: Error while reading PHY0 reg at 3.3
====================
Signed-off-by: David S. Miller <davem@davemloft.net>