The driver had no d_ioctl, so CONFIG_NETDEV_PHY_IOCTL had no effect.
Implement SIOCGMIIPHY, SIOCGMIIREG and SIOCSMIIREG and, with
CONFIG_ARCH_PHY_INTERRUPT, SIOCMIINOTIFY. SIOCMIINOTIFY subscribes
through phy_notify_subscribe() (the board provides arch_phy_irq()) and
enables the PHY link down and auto-negotiation complete interrupts.
This is what CONFIG_NETINIT_MONITOR needs.
The PHY interrupt is implemented for the LAN8720 and LAN8740; add their
interrupt source/mask register bits to mii.h.
Assisted-by: Claude Code:claude-opus-5-5
Signed-off-by: Daniel P. Carvalho <danieloak@gmail.com>