[PATCH 2/3] mx7dsabre: Enable DM_ETH

[Fabio Estevam]

On Mon, Jan 27, 2020 at 2:57 PM Fabio Estevam <festevam at gmail.com> wrote:
>
> Hi Joris,
>
> On Mon, Jan 27, 2020 at 1:16 PM Joris OFFOUGA <offougajoris at gmail.com> wrote:
>
> > I can't find a fix yet.  If you find one it would be great.
>
> I noticed that the Ethernet regression happens because the ENET_RST_B
> signal keeps always at 0, which makes the PHY to never becomes active.
>
> The Ethernet PHY reset comes from a GPIO expander (74LV595PW), which
> is connected to SPI GPIO lines.
>
> Both the GPIO expander driver (CONFIG_DM_74X164) as well as the SPI
> GPIO driver (CONFIG_SOFT_SPI) are enabled at
> configs/mx7dsabresd_defconfig.
>
> The device tree has:
>
> &fec1 {
> ....
> phy-reset-gpios = <&extended_io 5 GPIO_ACTIVE_LOW>;
>
> Port 5 of the 74LV595PW is the Ethernet PHY reset pin.
>
> However, this is what we get in U-Boot:
>
> Net:   Could not get PHY for FEC0: addr 0
> No ethernet found.
>
> Not sure why DM is not properly bringing the Ethernet PHY back to 1.

Running "dm tree" says that soft_spi has not been probed:

 spi           0  [   ]   soft_spi              |-- spi4

Not sure why soft_spi does not get probed though.

The IO expander is on the soft_spi bus, so we need to get soft_spi to
get probed first.

Thanks