Imx7d Ethernet port1 interfacing to DP83825 in RMII mode

[asmaa]

Hello All,

I am interfacing imx7d ethernet with DP83825 in RMII mode. My device tree setting is as follows:

I can connect to PHY but, after I check with the ethtool the link is not being detected. I get the following output.

Following the imx7d reference manual, the pin configuration was not clear for me in  RMII mode.

Is my pin setting for RMII is correct? Could somebody please confirm pin selection for RMII?

Thanks,

Asma

[igorpadykov]

Hi Asma

for rmii connections one can look at

RMII interface on the IMX7 

software rmii example in toradex colibri board

imx7-colibri.dtsi\dts\boot\arm\arch - linux-imx - i.MX Linux kernel 

Best regards
igor
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[asmaa]

Hi igorpadykov‌,

Thanks for the quick reply.

Looking at the above link

RMII interface on the IMX7 

looks like pad MX7D_PAD_ENET1_CRS__ENET1_CRS  is not right for CRS_DV.
Our hardware engineer said, he is not able to select ENET1.RX_CTL for CRS_DV in Pin Tool for i.Mx.

Could you please confirm, if we can use MX7D_PAD_ENET1_CRS__ENET1_CRS for CRS_DV or not?

Thanks,

Asma

[igorpadykov]

Hi Asma

suggest to try toradex colibri board configuration given above, it works as

CRS_DV in RMII mode inspite of naming.

Best regards
igor

[asmaa]

Hi Igor,

toradex colibiri board is using following device tree settings

pinctrl_enet1: enet1grp {
   
      fsl,pins = <    
        MX7D_PAD_ENET1_CRS__GPIO7_IO14   0x14 
        MX7D_PAD_ENET1_RGMII_RX_CTL__ENET1_RGMII_RX_CTL 0x73   
        MX7D_PAD_ENET1_RGMII_RD0__ENET1_RGMII_RD0 0x73   
 MX7D_PAD_ENET1_RGMII_RD1__ENET1_RGMII_RD1 0x73   
 MX7D_PAD_ENET1_RGMII_RXC__ENET1_RX_ER  0x73    
 MX7D_PAD_ENET1_RGMII_TX_CTL__ENET1_RGMII_TX_CTL 0x73   
 MX7D_PAD_ENET1_RGMII_TD0__ENET1_RGMII_TD0 0x73   
 MX7D_PAD_ENET1_RGMII_TD1__ENET1_RGMII_TD1 0x73   
 MX7D_PAD_GPIO1_IO12__CCM_ENET_REF_CLK1  0x73  
 MX7D_PAD_SD2_CD_B__ENET1_MDIO   0x3  
 MX7D_PAD_SD2_WP__ENET1_MDC   0x3  
>;  
};

So that means they are using ENET1.RX_CTL for CRS_DV and we have use ENET1_CRS for CRS_DV. which means we have used the wrong PAD. Is that right?

Could you now confirm that?

Regards,

Asma

[igorpadykov]

Hi Asma

>we have use ENET1_CRS for CRS_DV. which means we have used the wrong PAD. Is that right?

right, actually for CRS_DV Table shows in "Pad" column ENET1.RX_CTL.

Best regards
igor

[asmaa]

Thanks igorpadykov‌