Re: [PATCH net-next v1 2/3] dt-bindings: net: micrel: Add keep-preamble-before-sfd
From: "Rob Herring (Arm)" <robh@kernel.org>
Date: 2025-12-12 10:29:50
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linux-devicetree, lkml
On Fri, 12 Dec 2025 09:46:17 +0100, Stefan Eichenberger wrote:
From: Stefan Eichenberger <redacted> Add a property to activate a Micrel PHY feature that keeps the preamble enabled before the SFD (Start Frame Delimiter) is transmitted. This allows to workaround broken Ethernet controllers as found on the NXP i.MX8MP. Specifically, errata ERR050694 that states: ENET_QOS: MAC incorrectly discards the received packets when Preamble Byte does not precede SFD or SMD. The bit which disables this feature is not documented in the datasheet from Micrel, but has been found by NXP and Micrel following this discussion: https://community.nxp.com/t5/i-MX-Processors/iMX8MP-eqos-not-working-for-10base-t/m-p/2151032 It has been tested on Verdin iMX8MP from Toradex by forcing the PHY to 10MBit. Withouth this property set, no packets are received. With this property set, reception works fine. Signed-off-by: Stefan Eichenberger <redacted> --- Documentation/devicetree/bindings/net/micrel.yaml | 13 +++++++++++++ 1 file changed, 13 insertions(+)
My bot found errors running 'make dt_binding_check' on your patch: yamllint warnings/errors: ./Documentation/devicetree/bindings/net/micrel.yaml:517:1: [warning] too many blank lines (2 > 1) (empty-lines) dtschema/dtc warnings/errors: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/net/renesas,ether.example.dtb: ethernet-phy@1 (ethernet-phy-id0022.1537): compatible: ['ethernet-phy-id0022.1537', 'ethernet-phy-ieee802.3-c22'] is too long from schema $id: http://devicetree.org/schemas/net/micrel.yaml doc reference errors (make refcheckdocs): See https://patchwork.kernel.org/project/devicetree/patch/20251212084657.29239-3-eichest@gmail.com The base for the series is generally the latest rc1. A different dependency should be noted in *this* patch. If you already ran 'make dt_binding_check' and didn't see the above error(s), then make sure 'yamllint' is installed and dt-schema is up to date: pip3 install dtschema --upgrade Please check and re-submit after running the above command yourself. Note that DT_SCHEMA_FILES can be set to your schema file to speed up checking your schema. However, it must be unset to test all examples with your schema.