Describe the bug
On the Xiaomi AX3000T hardware revision with the Airoha AN8855 switch (introduced in units shipped with stock firmware 1.0.84+), hardware flow offloading is non-functional. The AN8855 switch driver fails to fully initialize at boot, resulting in the following kernel log entry:
an8855-switch: probe of an8855-switch.2.auto failed with error -110
Because the switch driver does not successfully probe, the kernel flowtable cannot offload flows to the hardware PPE, and enabling flow_offloading_hw has no effect or causes instability. Software flow offloading (flow_offloading '1' with flow_offloading_hw '0') works correctly and is stable as a workaround.
Steps to reproduce
- Use a Xiaomi AX3000T with AN8855 switch (stock firmware version ≥ 1.0.84)
- Flash OpenWrt 25.12.x
- Enable Hardware Flow Offloading in Network → Firewall → Routing/NAT Offloading
- Observe that hardware offloading has no effect;
dmesgshows the probe failure at boot
Expected behavior
Hardware flow offloading should function on the AN8855 switch, as it does on the older MT7530/MT7531 revision of the same router.
Actual behavior
The AN8855 switch driver fails to probe with error -110 (timeout), preventing hardware flow offloading from working entirely.
Boot log confirms the probe failure:
[ 1.852202] an8855-switch an8855-switch.2.auto: probe with driver an8855-switch failed with error -110
Workaround
Disable hardware flow offloading, use software flow offloading only:
/etc/config/firewall:
option flow_offloading '1'
option flow_offloading_hw '0'
Environment
- Device: Xiaomi Mi Router AX3000T (AN8855 hardware revision)
- SoC: MediaTek MT7981B (Filogic 820)
- Switch chip: Airoha AN8855
- OpenWrt version: 25.12.0
- Kernel: 6.12.87 (SMP Mon May 25 02:36:00 2026 aarch64)
Additional context
The AN8855 driver was introduced via PR #16709. During that PR's review and testing, a contributor noted instability related to the AN8855 switch under certain traffic conditions, which may be related to the incomplete driver initialization. The driver probe failure suggests the flowtable offload hook is never registered for this switch, leaving hardware acceleration permanently unavailable on affected units.
As the AX3000T is one of the most widely used budget routers in the OpenWrt community, a large number of users with the AN8855 revision are currently unable to use hardware flow offloading.
