PROCESSOR-SDK-AM335X: AM335x: Using two GPIO to reset two different ethernet PHY

Hello Woody, 

Thank you for the query.

Can you please help us under the issue better. Ae you trying to reset both the PHY at the same time and are the PHYs not getting reset

Are you seeing the reset toggling. 

Regards,

Sreenivasa

Hi Kallikuppa,

No, I only see one ethernet PHY be reset.

Please see logs as below

[    1.965119] libphy: Fixed MDIO Bus: probed
[    2.041583] davinci_mdio 4a101000.mdio: davinci mdio revision 1.6, bus freq 1000000
[    2.049290] libphy: 4a101000.mdio: probed
[    2.060458] mdio_bus 4a101000.mdio: MDIO device at address 1 is missing.
[    2.067302] davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver TI DP83867
[    2.075814] cpsw 4a100000.ethernet: initialized cpsw ale version 1.4
[    2.082336] cpsw 4a100000.ethernet: ALE Table size 1024
[    2.087683] cpsw 4a100000.ethernet: cpts: overflow check period 500 (jiffies)
[    2.094963] cpsw 4a100000.ethernet: Detected MACID = 24:76:25:32:d0:5d

You can see one TI DP83867 is detected, but address 1 is missing.

Please see DTS file content as below, 

&davinci_mdio {
        pinctrl-names = "default", "sleep";
        pinctrl-0 = <&davinci_mdio_default>;
        pinctrl-1 = <&davinci_mdio_sleep>;
        status = "okay";

        reset-gpios = <&gpio0 6 GPIO_ACTIVE_LOW &gpio3 19 GPIO_ACTIVE_LOW>;
        reset-delay-us = <2>;   /* PHY datasheet states 1uS min */

        ethphy0: ethernet-phy@0 {
                reg = <0>;
        };

        ethphy1: ethernet-phy@1 {
                reg = <1>;
        };
};

Do you have any idea on this? Thanks.

Hello Woddy, 

Thank you for the inputs.

Can you please check on the board if both devices are being reset (receiving reset pulse). What is the address you are setting for both devices 

Regards,

Sreenivasa

Hi Kallikuppa,

1. I only see one phy being reset on PHY address 0.

2. Do you mean phy address? It's address 0 and address 1. You can see these in boot logs.

[ 2.060458] mdio_bus 4a101000.mdio: MDIO device at address 1 is missing.
[ 2.067302] davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver TI DP83867

Do you have patches to fix this issue? Thanks.

Hello Woddy, 

Thank you for the inputs. Have you had a chance to check the board hardware as below.

Can you please check on the board if both devices are being reset (receiving reset pulse). What is the address you are setting for both devices 

I am not aware of a patch but will check.

Regards,

Sreenivasa

Hi Kallikuppa,

1. I can see "gpio0 6" being reset that pull up to +3.3V but gpio3 19 doesn't.

2. PHY address are 0 and 1.

Kallikuppa Sreenivasa said:

What is the address you are setting for both devices 

Hello Woody,

Thank you for replying.

I do not have the schematics. Based on what you explain, i understand one of the port toggles and that PHY is getting reset.

The Other PHY is not toggling and the PHY doe not reset. If yes may be for testing, pls try connecting the same working port to both the PHYs to check if the PHY reset works (hardware wise).

Regards,

Sreenivasa

Hi Kallikuppa,

Yes, I had tried that before and it worked.

But I can't modify hardware design so I have to fix it in firmware.

Could you help me check how to fix it on am335x platform? Thanks for your help.

Hello Woddy, 

Thank you for confirming. 

Let me check infernally how best we can support. Please expect delay in response as i check internally.

Regards,

Sreenivasa

Hello Woddy, 

I could not get information on availability of the code or patch  to perform the function that you have been looking for..

Regards,

Sreenivasa

Hi Kallikuppa,

Got it. Thanks.