On 17/10/2026 13:14, Michael Serajnik wrote:
What I see:
- `ethtool eno1` shows "Supports Wake-on: pumbg" and "Wake-on: g".
- BIOS: ErP disabled, Power On By PCI-E enabled.
- /proc/acpi/wakeup has the NIC and every port on its path enabled.
- After `systemctl poweroff`, the port LEDs go dark, the switch sees
no link, and a magic packet from the same subnet does not wake the
machine.
Register read:
With igc unbound (strict devmem refuses the mmap while it is bound),
I read BAR0 + 0xE14 (IGC_I225_PHPM):
PHPM = 0x00045298
DIS_1000_D3 (0x0008), DIS_100_D3 (0x0200), DIS_2500_D3 (0x1000)
are all set (mask 0x1208).
As a sanity check, RAL0 (0x5400) read 0x62e7fcbc, which matches the
MAC address bc:fc:e7:62:d6:2f.
These bits come from the NIC's NVM, not from the board firmware, and
FreeBSD bug 282140 (below) reports the same link-disable bits on other
hardware, so I do not expect a BIOS update to change this. [1]
With all three speeds disabled in D3, the PHY has no link while the
device is in D3, so the magic packet never reaches the MAC, however
WUFC is programmed. In mainline igc, `__igc_shutdown()` sets WUC,
WUFC and CTRL.ADVD3WUC and calls `igc_power_up_link()`, but nothing
in the driver clears these PHPM bits, and igc defines neither the
bits nor a D3 LPLU operation.
Hi Michael,
With these bits cleared, the link should resolve to the lowest, 10Mbps
speed. In recent years, an increasing number of switches stopped
supporting 10Mbps, so we have been receiving reports of similar problems
from time to time.
I think I can fix it in the driver, but to double-check that the problem
is indeed this, and not something else in the wake-from-shutdown path,
could you try to reproduce with a different link partner (switch or
back-to-back) that is known to support 10Mbps link speed?
Thanks!
--Dima
