Re: [PATCH v5 0/7] describe RTL8125 PCIe NICs on Rockchip boards (and add DT binding)

From: Ricardo Pardini

Date: Wed Sep 23 2026 - 15:10:21 EST


On 22/09/2026 11:17, Geert Uytterhoeven wrote:
Hi Ricardo,

On Thu, 10 Sept 2026 at 22:08, Ricardo Pardini via B4 Relay
<devnull+ricardo.pardini.net@xxxxxxxxxx> wrote:
Several Rockchip rk35xx boards carry on-board Realtek RTL8125 2.5GbE
NICs whose PCI function nodes are not described in the DT. Describing
them allows for stable ethernetN aliases (matching the GMAC alias
convention on these boards) and lets U-Boot's fdt_fixup_ethernet()
inject mac-address properties from its ethaddr/ethNaddr env, so MACs
stay stable across boots and U-Boot and kernel MAC match.

Tested on a NanoPC-T6: /sys/bus/pci/devices/0004:41:00.0/of_node ->
/sys/firmware/devicetree/base/pcie@fe190000/pcie@0,0/ethernet@0,0 and
u-boot correctly adds local-mac-address property there which is
correctly picked up kernel-side:

Have you tested this at 2.5Gbps? With which firmware?
I am asking because I have problems at 2.5Gbps using the firmware from
linux-firmware (on a different platform, though)
https://lore.kernel.org/CAMuHMdXPAeHoeaQbM9rXbXukoMbFV+0k28n6sRMw8XF8720WUA@xxxxxxxxxxxxxx

Hi Geert, yes, the RTL8125's on those boards work at 2.5gbps just fine (both with and without the fixed-function nodes in this series). They do get quite warm at 2.5gbps. I'm using one of those el-cheapo 8-port 2.5gbps switches.

Currently:

[ 3.254450] r8169 0002:21:00.0 eth0: RTL8125B, 8e:b4:90:97:32:30, XID 641, IRQ 124
...
[ 10.480872] r8169 0002:21:00.0 end0: Link is Up - 2.5Gbps/Full - flow control rx/tx

# sensors r8169_2_2100:00-mdio-0
r8169_2_2100:00-mdio-0
Adapter: MDIO adapter
temp1: +52.0°C (high = +120.0°C)

I'm using whatever is in Armbian's armbian-firmware package:

# ethtool -i end0 | grep -i firmware
firmware-version: rtl8125b-2_0.0.2 07/13/20

# sha256sum /lib/firmware/rtl_nic/rtl8125b-2.fw
529bf1c25c97ff52b401090d00ff89cc22351012336e5a0c9662728a3ee909ef /lib/firmware/rtl_nic/rtl8125b-2.fw


mvg,
Ricardo


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