topic LS1043A Jumbo frame support in Linux Mainline in Layerscape

LS1043A Jumbo frame support in Linux Mainline

timsalabim — Mon, 13 Oct 2025 10:58:08 GMT

Dear NXP support,

we are evaluating Jumbo Frames on LS1043A with a custom specific board, but when changing the MTU size in Linux the system shows:

Error: mtu greater than device maximum.

During my research, I came across the following NXP Community thread:
https://community.nxp.com/t5/Layerscape/Why-is-LS1043-MTU-limited-to-2K-not-4K/m-p/847022

Which refers to FMAN Errata A-010022 and a patch to fix this behavior in the NXP LSDK Kernel.
But I did not find anything similar for Linux Mainline Kernel, are there any fixes NXP can provide to support Jumbo Frames ?

thank you in advance

Re: LS1043A Jumbo frame support in Linux Mainline

LFGP — Mon, 13 Oct 2025 14:49:48 GMT

Dear @timsalabim,

Did you set the DPAA Ethernet driver into the Kernel to support jumbo frames?
please review, into the LLDP user manual, the subsection "7.2.2.5.2.2 Kconfig options" and the "7.2.2.5.3.3 Jumbo frames support".
BR
LFGP

Re: LS1043A Jumbo frame support in Linux Mainline

timsalabim — Mon, 13 Oct 2025 15:44:07 GMT

Hello,

thanks for the reply, the mentioned option are only available in the NXP based Linux kernel, which uses CONFIG_FSL_SDK_DPAA

https://docs.nxp.com/bundle/UG10081_LLDP_L6.1.55_2.2.0/page/topics/jumbo_frames_support.html

In the Linux Mainline kernel CONFIG_FSL_DPPA_ETH is used which does not have the extended options in the kernel menuconfig

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/net/ethernet/freescale/dpaa/Kconfig?h=v6.12.52

best regards

Tim

Re: LS1043A Jumbo frame support in Linux Mainline

LFGP — Tue, 14 Oct 2025 23:43:50 GMT

Dear @timsalabim,
unfortunately we don't have anything for the Linux Mainline Kernel regarding jumbo frames, due they are managed by the block DPAA we recommend to use the NXP SDK.

BR
LFGP

Re: LS1043A Jumbo frame support in Linux Mainline

timsalabim — Thu, 23 Oct 2025 09:28:49 GMT

Hello LFGP,

thank you for the reply, Since Layerscape CPUs are primarily intended for network equipment, we as manufacturer are very interested in using the Linux mainline kernel, as the platforms are supported for a very long time and we are not dependent on NXP for kernel updates. This is becoming increasingly important for us and our customers, especially in light of the Cyber Resilience Act.

best regards

Tim