While testing the lantiq_gswip driver in OpenWrt at least one board had a non-working Ethernet port connected to an internal 100Mbit/s PHY22F GPHY. The problem which could be observed: - the PHY would detect the link just fine - ethtool stats would see the TX counter rise - the RX counter in ethtool was stuck at zero
It turns out that two independent patches are needed to fix this: - first we need to enable the MII data lines also for internal PHYs - second we need to program the GSWIP_MII_CFG registers for all ports except the CPU port These two patches have also been tested by back-porting them on top of Linux 5.4.86 in OpenWrt. Special thanks to Hauke for debugging and brainstorming this on IRC with me! Martin Blumenstingl (2): net: dsa: lantiq_gswip: Enable GSWIP_MII_CFG_EN also for internal PHYs net: dsa: lantiq_gswip: Fix GSWIP_MII_CFG(p) register access drivers/net/dsa/lantiq_gswip.c | 27 +++++++-------------------- 1 file changed, 7 insertions(+), 20 deletions(-) -- 2.30.0
