topic Re: flexbuilder lsdk2108 support for SERDES1 protocol 0x3333 in Layerscape

flexbuilder lsdk2108 support for SERDES1 protocol 0x3333

nagurvalisayyad — Mon, 04 May 2026 09:56:32 GMT

Hi,

We are using LS1046A in our custom board and the images are compiled using flexbuild lsdk2108 and our design is as similar to the ARDB development kit. The SERDES1 supports two 10G ports and two 1G ports and SERDES2 is not used.

We have compiled images accroding to our custom board and everything is working fine, both 10G ports(xgmii) and 1G ports(sgmii) are working properly. In one of our application, we want to use both 10G ports as 1G ports. For this, we have changed the rcw, uboot and linux dts files. The files are attached for reference.

After the compilation and board booting, we could see that the linux log is still looking for 10G ports and the ubuntu file system is not showing fm1-mac1 and fm1-mac2 ports.The boot log is attached for reference.

It is evident from the boot log that, we are missing something that needs to be changed. In this regard, it is reqested to support which files needs to be modified to meet our requirements.

Thanks & Regards--

Nagurvali Sayyad.

Re: flexbuilder lsdk2108 support for SERDES1 protocol 0x3333

Bio_TICFSL — Mon, 04 May 2026 14:05:59 GMT

Hello,

Yes — for LS1046A, changing the two 10G SerDes1 ports to 1G is not just a Linux DTS change. You need all three layers aligned: RCW , U-Boot board Ethernet fixup , and Linux DTS . If Linux still probes the 10G ports and fm1-mac1 / fm1-mac2 do not appear, the most likely issue is that U-Boot is still disabling those MAC nodes in the DT before Linux boots

To make the two LS1046A 10G ports work as 1G ports, you must change the RCW to an SGMII protocol such as 0x3333 , update U-Boot eth.c so it does not disable those MAC nodes, and update the Linux DTS so those ports are described as sgmii with the correct PHY or fixed-link configuration.

regards

Re: flexbuilder lsdk2108 support for SERDES1 protocol 0x3333

nagurvalisayyad — Tue, 05 May 2026 03:58:19 GMT

Hi,

Thanks for the reply. As suggested, changes are done in rcw, u-boot and linux dts files. It can be seen in the previous log file attached, the initial messages are showing as below.

"eth0: fm1-mac1, eth1: fm1-mac2, eth2: fm1-mac3, eth3: fm1-mac4, eth4: fm1-mac5, eth5: fm1-mac6
"

After changing the u-boot dts file, fm1-mac1 and fm1-mac2 are appeared. Can you please suggest us what modifications needs to be done in eth.c file.

In addtition, is it required to modify any other files.

Thanks & Regards--

Nagurvali Sayyad.