U-Boot atheros PHY support and cubox ethernet

[Fabio Estevam]

Hi Soeren,

On Wed, Jun 24, 2020 at 4:20 PM Soeren Moch <smoch at web.de> wrote:

> I tested current master (v2020.07-rc5 + imx fixes) on tbs2910 (imx6q +
> atheros PHY).
> Unfortunately ethernet is broken now, while it used to work well on
> u-boot version v2020.04. Ethernet support was copied from imx6q-sabresd,
> the recently for sabresd fixed phy-mode already is rgmii-id for tbs2910.
>
> Any ideas what could be wrong?

I just tested mainline U-Boot and Ethernet works fine on a imx6qp sabresd board:

U-Boot SPL 2020.07-rc5-00052-g922c6d5d00 (Jun 24 2020 - 16:21:27 -0300)
Trying to boot from MMC1


U-Boot 2020.07-rc5-00052-g922c6d5d00 (Jun 24 2020 - 16:21:27 -0300)

CPU:   Freescale i.MX6QP rev1.0 996 MHz (running at 792 MHz)
CPU:   Automotive temperature grade (-40C to 125C) at 30C
Reset cause: POR
Model: Freescale i.MX6 Quad Plus SABRE Smart Device Board
Board: MX6-SabreSD
I2C:   ready
DRAM:  1 GiB
PMIC:  PFUZE100 ID=0x10
MMC:   FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 3
Loading Environment from MMC... OK
No panel detected: default to Hannstar-XGA
Display: Hannstar-XGA (1024x768)
In:    serial
Out:   serial
Err:   serial
Net:   eth0: ethernet at 2188000
Hit any key to stop autoboot:  0
=> dhcp zImage
BOOTP broadcast 1
DHCP client bound to address 192.168.0.24 (50 ms)
Using ethernet at 2188000 device
TFTP from server 192.168.0.12; our IP address is 192.168.0.24
Filename 'zImage'.
Load address: 0x12000000
Loading: #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         #############################################################
         1.3 MiB/s
done
Bytes transferred = 9468928 (907c00 hex)
=> mdio list
FEC0:
1 - AR8031/AR8033 <--> ethernet at 2188000
=>

What is the exact failure you see? Is the Ethernet PHY found at the
correct address and probed?

On tbs2910 does the AR8031 generate a 125MHz clock to the i.MX6Q Ethernet?

If so, does the change below help (I am assuming the PHY is located at
address 1, if not, please adjust the @ and reg accordingly)?

--- a/arch/arm/dts/imx6q-tbs2910.dts
+++ b/arch/arm/dts/imx6q-tbs2910.dts
@@ -108,6 +108,16 @@
        phy-mode = "rgmii-id";
        phy-reset-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
        status = "okay";
+
+       mdio {
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               phy: ethernet-phy at 1 {
+                       reg = <1>;
+                       qca,clk-out-frequency = <125000000>;
+               };
+       };
 };

In case you still have issues, please share the tbs2910 schematics
with me offline so I can try to understand the failure.