[PATCH v2 1/2] arm64: dts: meson-gxbb-odroidc2: read the Ethernet MAC address from eFuse

[Fil Dunsky]

Hi Martin,

On Sun, Oct 11, 2026 at 10:49 PM Martin Blumenstingl
<martin.blumenstingl at googlemail.com> wrote:
> Question to Neil: should the eth_mac node be moved from meson-gx.dtsi
> to meson-gxbb-odroidc2.dts?
> Odroid-C2 would be the only board using it and u-boot seems to derive
> MAC from SoC chip ID/serial number instead of reading it from eFuse
> (so I'm not sure about the status of MAC address in eFuse on most
> boards).

Some data points in case they help Neil decide:

- Mainline U-Boot does read the eFuse first on the GX reference board
  files: board/amlogic/p200 (used by odroid-c2_defconfig), p201, p212
  and q200 all call meson_sm_read_efuse(EFUSE_MAC_OFFSET = 52, 6 bytes)
  and only fall back to meson_generate_serial_ethaddr() when that does
  not give a valid address.

- On my ODROID-C2 the eFuse at 0x34 holds 00:1e:06:37:d9:37, i.e.
  Hardkernel's OUI, and that is what U-Boot passes on today.

I can't say how many other GX boards have the eFuse programmed, so I
have no strong opinion on where the node should live. Happy to respin
with the cell moved into the board file if that is preferred.

Thanks for the review,
Fil