Re: [PATCH v5 5/7] arm64: dts: rockchip: describe PCIe RTL8125 Ethernet on NanoPi R5S

[Ricardo Pardini <ricardo@pardini.net>]

On 23/09/2026 19:15, Diederik de Haas wrote:
> Hi,
> 
> On Thu Sep 10, 2026 at 10:07 PM CEST, Ricardo Pardini via B4 Relay wrote:
>> From: Ricardo Pardini <ricardo@pardini.net>
>>
>> The FriendlyElec NanoPi R5S (rk3568) carries two on-board Realtek
>> RTL8125 NICs behind pcie2x1 and pcie3x1, alongside the existing gmac0
>> RGMII PHY.
>>
>> Describe the fixed function nodes and attach ethernet1/ethernet2
>> aliases (ethernet0 stays mapped to gmac0), so that U-Boot's
>> fdt_fixup_ethernet() can inject mac-address properties from its
>> eth1addr/eth2addr env, for stable MACs across boots that both U-Boot
>> and the kernel agree on.
>>
>> Signed-off-by: Ricardo Pardini <ricardo@pardini.net>
>> ---
>>   arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts | 30 ++++++++++++++++++++++
>>   1 file changed, 30 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts b/arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts
>> index 90ce6f0e1dcff..9ed11663c31c9 100644
>> --- a/arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts
>> +++ b/arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts
>> @@ -15,6 +15,8 @@ / {
>>   
>>   	aliases {
>>   		ethernet0 = &gmac0;
>> +		ethernet1 = &rtl_eth1;
>> +		ethernet2 = &rtl_eth2;
>>   	};
> 
> With my NanoPi-R5S I'm still getting the following warning:
> 
>    r8169 0001:11:00.0: can't read MAC address, setting random one
> 
> ```
> root@nanopi-r5s:~# ip link
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
>      link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
> 2: end1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN mode DEFAULT group default qlen 1000
>      link/ether 4e:52:85:9e:22:f9 brd ff:ff:ff:ff:ff:ff
>      altname enp1s0
>      altname enx4e52859e22f9
> 3: end2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN mode DEFAULT group default qlen 1000
>      link/ether 12:e5:47:9e:e2:f1 brd ff:ff:ff:ff:ff:ff
>      altname enP1p17s0
> 4: end0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
>      link/ether 4e:52:85:9e:22:f8 brd ff:ff:ff:ff:ff:ff
>      altname enx4e52859e22f8
> ```
> 
> I did not do anything (explicitly) in U-Boot, but it seems it created a
> non-random MAC address for end0 and end1 ... and then stopped.
> AFAIK gmac0=end0 already had a non-random MAC address and I hoped/expected
> it would create non-random addresses for end1 and end2, which would've made
> the above warning go away too.
> 
> Is this an issue with this patch, with U-Boot or me?

Hi Diederik, in this case (3 ethernet's) I think it's down to U-boot.
Check the output of `printenv` in u-boot, you'll probably find it only 
pre-computes 2 MAC addresses, and doesn't feed the ethernet2 alias 
during its fdt_fixup_ethernet().

Try doing `setenv eth2addr xx:xx...` in u-boot before booting -- it 
should work. I think that's what I did when testing the R5S with this 
series, but it has been a very long time ago.

One way around this (without u-boot) would be to use Alexey's series [1] 
which could compute as many MACs as needed out of the CPU serialnum - 
but that also won't work as-sent vs rk356x, I believe he's checking an 
alternative proposed.

[1] 
https://lore.kernel.org/linux-rockchip/20260902-rk3576-otp-cpuid-mac-v2-0-e4b7fe2ab13f@flipper.net/

> 
> Full details:
> https://paste.sr.ht/~diederik/8ae7d354985afcd1c3464e3a4ad81da1b4442364
> 
> Side note:
> I wonder how 'random' those addresses are as during testing ``ssh rock5b``
> landed me on another device (NanoPC-T6 Plus), f.e. My router has DHCP
> reservations based on MAC addresses and it looks like it got confused ;-)

Interesting. I dunno what seed is used, as I've been fully set on making 
it non-random, but I wouldn't discard the possibility of conflicts 
across different machines. One more reason to have this series ;-)

I'll soon send a v6 to linux-rockchip/dt (with small fixes Sashiko found 
to DTs, and without the binding) and split a single-patch v1 to net-next 
with only the binding, collecting Rob's review. If and when those land, 
we'd have open road both for u-boot local-mac-address and Alexey's 
nvmem-cells for the RTLs.

Regards,
Ricardo


> 
> Cheers,
>    Diederik
> 
>>   	gpio-keys {
>> @@ -107,6 +109,20 @@ &pcie2x1 {
>>   	num-lanes = <1>;
>>   	reset-gpios = <&gpio0 RK_PB6 GPIO_ACTIVE_HIGH>;
>>   	status = "okay";
>> +
>> +	pcie@0,0 {
>> +		reg = <0x000000 0 0 0 0>;
>> +		#address-cells = <3>;
>> +		#size-cells = <2>;
>> +		ranges;
>> +		device_type = "pci";
>> +		bus-range = <0x00 0x0f>;
>> +
>> +		rtl_eth1: ethernet@0,0 {
>> +			compatible = "pci10ec,8125";
>> +			reg = <0x010000 0 0 0 0>;
>> +		};
>> +	};
>>   };
>>   
>>   &pcie30phy {
>> @@ -119,6 +135,20 @@ &pcie3x1 {
>>   	reset-gpios = <&gpio0 RK_PA0 GPIO_ACTIVE_HIGH>;
>>   	vpcie3v3-supply = <&vcc3v3_pcie>;
>>   	status = "okay";
>> +
>> +	pcie@0,0 {
>> +		reg = <0x100000 0 0 0 0>;
>> +		#address-cells = <3>;
>> +		#size-cells = <2>;
>> +		ranges;
>> +		device_type = "pci";
>> +		bus-range = <0x10 0x1f>;
>> +
>> +		rtl_eth2: ethernet@0,0 {
>> +			compatible = "pci10ec,8125";
>> +			reg = <0x110000 0 0 0 0>;
>> +		};
>> +	};
>>   };
>>   
>>   &pcie3x2 {
>