Hi all,
During the last few months, booting kernels on BeagleBone Black
sometimes fails with:
+SMSC LAN8710/LAN8720 4a101000.mdio:00: probe with driver SMSC
LAN8710/LAN8720 failed with error -5
davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00,
driver SMSC LAN8710/LAN8720
soc_device_match(cpsw_soc_devices): no match
cpsw-switch 4a100000.switch: initialized cpsw ale version 1.4
...
am335x-phy-driver 47401300.usb-phy: dummy supplies not allowed
for exclusive requests (id=vbus)
+cpsw-125mhz-clkctrl:0014:0: failed to disable
am335x-phy-driver 47401b00.usb-phy: using DT
'/ocp/target-module@47400000/usb-phy@1b00' for 'reset' GPIO lookup
...
cpsw-switch 4a100000.switch: starting ndev. mode: dual_mac
-SMSC LAN8710/LAN8720 4a101000.mdio:00: attached PHY driver
(mii_bus:phy_addr=4a101000.mdio:00, irq=POLL)
-cpsw-switch 4a100000.switch eth0: Link is Up - 100Mbps/Full -
flow control off
-Sending DHCP requests ., OK
-IP-Config: Complete:
-[...]
+cpsw-switch 4a100000.switch: phy
"/ocp/interconnect@4a000000/segment@0/target-module@100000/switch@0/mdio@1000/ethernet-phy@0"
not found on slave 0
+[HANG]
Adding debug prints to smsc_phy_probe() makes the issue go away, so it
must be timing related.
Adding specific debug prints in the failure case gives:
SMSC LAN8710/LAN8720 4a101000.mdio:00: genphy_read_abilities:2859:
phy_read(MII_BMSR) failed -EIO
SMSC LAN8710/LAN8720 4a101000.mdio:00: phy_probe:3613:
genphy_read_abilities() failed -EIO
SMSC LAN8710/LAN8720 4a101000.mdio:00: probe with driver SMSC
LAN8710/LAN8720 failed with error -5
and later:
Generic PHY 4a101000.mdio:00: genphy_read_abilities:2859:
phy_read(MII_BMSR) failed -EIO
Generic PHY 4a101000.mdio:00: phy_probe:3609:
genphy_read_abilities failed -EIO
cpsw-switch 4a100000.switch: phy
"/ocp/interconnect@4a000000/segment@0/target-module@100000/switch@0/mdio@1000/ethernet-phy@0"
not found on slave 0
Adding debug prints to __mdiobus_read() and davinci_mdio_read() gives:
mdio_bus 4a101000.mdio: davinci_mdio_read:444:
readl(&data->regs->user[0].access) = 0x3a0ffff
mdio_bus 4a101000.mdio: __mdiobus_read:900: davinci_mdio_read failed -EIO
but this is a different (and unimportant?) early failure from
smsc_phy_config_intr(), and that debug print actually makes the issue go
away, too.
Ignoring the early failure reveals that phy_read(MII_BMSR) failed due
to:
mdio_bus 4a101000.mdio: davinci_mdio_read:446:
readl(&data->regs->user[0].access) = 0x20ffff
Anyone with a clue?
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
