LS1046a MAC to MAC 1000base-kx connection

[m-rains]

Hello all,

I have an issue that likely has a simple solution. I have two LS1046's on a custom board that I am attempting to connect together MAC to MAC. My RCW serdes settings are 0x3040 0x5A06, and this 1000base-kx link is on MAC 2 (serdes 2, lane B).

In u-boot, the devices can ping each other over SGMII, and I am in the early stages of writing a 1000base-kx driver. The important thing is they can see eachother.

This is using yocto 3.1.1, kernel 5.4.3, and I took fsl_backplane.c from linux-extras.

In linux, the device fails to probe with error -12. Ignore the other errors on other interfaces, I just don't have them disabled in the device tree currently. I did add a few printk's in the dpaa_eth driver

[    8.419458] fsl_dpa: dpaa_eth.c:1143:dpa_load() FSL DPAA Ethernet driver

[    8.426269] Probing soc:fsl,dpaa:ethernet@0

[    8.428002] fsl_dpa: dpaa_eth.c:1086:dpaa_eth_priv_probe() fsl_dpa: Probed interface eth0

[    8.440411] Probing soc:fsl,dpaa:ethernet@2

[    8.440449] fsl_dpa soc:fsl,dpaa:ethernet@2: of_find_device_by_node(ethernet@e4000) failed

[    8.452909] fsl_dpa: probe of soc:fsl,dpaa:ethernet@2 failed with error -22

[    8.459895] Probing soc:fsl,dpaa:ethernet@4

[    8.461583] fsl_dpa: dpaa_eth.c:1086:dpaa_eth_priv_probe() fsl_dpa: Probed interface eth1

[    8.473990] Probing soc:fsl,dpaa:ethernet@5

[    8.475997] fsl_dpa: dpaa_eth.c:1086:dpaa_eth_priv_probe() fsl_dpa: Probed interface eth2

[    8.488411] Probing soc:fsl,dpaa:ethernet@8

[    8.488446] fsl_dpa soc:fsl,dpaa:ethernet@8: of_find_device_by_node(ethernet@f0000) failed

[    8.500904] fsl_dpa: probe of soc:fsl,dpaa:ethernet@8 failed with error -22

[    8.507890] Probing soc:fsl,dpaa:ethernet@9

[    8.510213] fsl_dpa: dpaa_eth.c:1086:dpaa_eth_priv_probe() fsl_dpa: Probed interface eth3

[    8.522608] fsl_advanced: dpaa_eth_base.c:193:dpa_advanced_load() FSL DPAA Advanced drivers:

[    8.531054] fsl_proxy: dpaa_eth_proxy.c:354:dpa_proxy_load() FSL DPAA Proxy initialization driver

[    8.540043] fsl_proxy-proxy soc:fsl,dpaa:ethernet@1: devm_kzalloc() failed

[    8.546926] fsl_proxy-proxy: probe of soc:fsl,dpaa:ethernet@1 failed with error -12

[    8.554604] fsl_oh: offline_port.c:823:oh_port_load() FSL FMan Offline Parsing port driver

I have primarily used this page and these questions for reference:

https://docs.nxp.com/bundle/GUID-9160E9B1-ADBC-4313-9837-773DA05262FB/page/GUID-0C4917DA-76E3-455C-A...

https://community.nxp.com/t5/Layerscape/LS1046A-serdes-backplane-eth-driver-amp-device-tree-question...

https://community.nxp.com/t5/QorIQ/Eval-Board-for-1000Base-KX-LS1046A/m-p/1178936

My device tree uses the following:

fsl-ls1046a_gpp.dts

&soc{

  serdes2: serdes@1eb0000 {

    reg = <0x0 0x1eb0000 0 0x00002000>;

    compatible = "fsl,serdes-10g";

    little-endian;

  };

  ...

};

&fman0 {

  mdio@e3000 {

    pcsphy1: ethernet-phy@0 {

      backplane-mode = "1000base-kx";

      compatible = "ethernet-phy-ieee802.3-c45";

      reg = <0x0>;

      fsl,lane-handle = <&serdes2>;

      fsl,lane-reg = <0x840 0x40>; /* lane B */

    };

  };

  ...

};

fsl-ls1046a_gpp-sdk.dts

&fsldpaa {

  ethernet@1 {

    compatible = "fsl,dpa-ethernet-init";

    fsl,fman-mac = <&enet1>;

    dma-coherent;

  };

  ...

};

1. Is a MAC to MAC link possible with this driver?

2. If so, what am I doing wrong?

3. I tried doing a SGMII link before this, though it is unconventional for this use case. I received error -22 when probing and couldn't figure it out. Should I go back to attempting this method?

Thank you. Verbosity is appreciated, as I am very new to this.

[m-rains · Accepted solution]

Just an update for any future readers - I was not able to figure out 1000base-kx, but I was able to figure out a fixed sgmii link, while unconventional, is good enough for my application.

There was an alias conflict in my device tree, making MAC 2 not probe. I don't know what driver caused this, unfortunately. Additionally, serdes 2 PLL 2 needed to be reset.

I changed ethernet1 to ethernetx1:

fsl-ls1046a_gpp.dts

&fman0 {

  ethernet@e2000 {

    fixed-link = <0 1 1000 0 0>;

    phy-connection-type = "sgmii";

  };

};

fsl-ls1046a_gpp-sdk.dts

&fsldpaa {

  ethernet@1 {

    compatible = "fsl,dpa-ethernet-init";

    fsl,fman-mac = <&enet1>;

    dma-coherent;

  };

};

fsl-ls1046a.dtsi

/ {

  aliases {

    ethernetx1 = &enet1;

  };

};

Serdes 2 PLL 2 reset, thanks to andreloddenkemp, source.
I inserted this into one of the last enet initialization driver probes via ioremap. Everything worked perfectly after that.

Regards,

m-rains

[SebastianG]

Hello @m-rains,

I would like to inform you that I'm working on your questions, I will let you know as soon as I have an update.

Thank you so much for your patience

Regards,

Sebastian

[m-rains]

Sebastian,
Thank you, I appreciate any help I can get.

Regards,
m-rains