[v2] ARM: imx6: DHCOM i.MX6 PDK: Convert to DM_ETH

Use DM_ETH instead of legacy networking.

Signed-off-by: Harald Seiler <hws at denx.de>
---

Notes:
    Changes in v2:
      - Move reset and VIO to device-tree
      - Always enable the clock, not just if CONFIG_FEC_MXC=y

 arch/arm/dts/imx6dl-dhcom-pdk2-u-boot.dtsi |  6 +++
 arch/arm/dts/imx6q-dhcom-pdk2-u-boot.dtsi  |  2 +
 arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi     | 22 ++++++++++
 board/dhelectronics/dh_imx6/dh_imx6.c      | 51 +---------------------
 configs/dh_imx6_defconfig                  |  2 +
 5 files changed, 34 insertions(+), 49 deletions(-)
 create mode 100644 arch/arm/dts/imx6dl-dhcom-pdk2-u-boot.dtsi
 create mode 100644 arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi

On 4/15/20 4:48 PM, Harald Seiler wrote:
> Use DM_ETH instead of legacy networking.

Some more descriptive commit message would help.

[...]

> diff --git a/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
> new file mode 100644
> index 000000000000..88840bb45920
> --- /dev/null
> +++ b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
> @@ -0,0 +1,22 @@
> +// SPDX-License-Identifier: (GPL-2.0+)
> +/*
> + * Copyright (C) 2020 Harald Seiler <hws at denx.de>
> + */
> +
> +/ {
> +	fec_vio: regulator-fec {
> +		compatible = "regulator-fixed";
> +
> +		regulator-name = "fec-vio";
> +		gpio = <&gpio1 7 GPIO_ACTIVE_HIGH>;
> +		regulator-always-on;
> +	};
> +};

The VIO regulator is on the pdk2, so it should be in the PDK2 U-Boot extras.

> +&fec {
> +	phy-reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
> +	phy-reset-duration = <1>;
> +	phy-reset-post-delay = <10>;

So is the PHY, so this should also be in the PDK2 extras.

(and it should be fixed in Linux too eventually, if it's not done yet)

[...]

Hello Marek,

On Wed, 2020-04-15 at 16:53 +0200, Marek Vasut wrote:
> On 4/15/20 4:48 PM, Harald Seiler wrote:
> > Use DM_ETH instead of legacy networking.
> 
> Some more descriptive commit message would help.
> 
> [...]
> 
> > diff --git a/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
> > new file mode 100644
> > index 000000000000..88840bb45920
> > --- /dev/null
> > +++ b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
> > @@ -0,0 +1,22 @@
> > +// SPDX-License-Identifier: (GPL-2.0+)
> > +/*
> > + * Copyright (C) 2020 Harald Seiler <hws at denx.de>
> > + */
> > +
> > +/ {
> > +	fec_vio: regulator-fec {
> > +		compatible = "regulator-fixed";
> > +
> > +		regulator-name = "fec-vio";
> > +		gpio = <&gpio1 7 GPIO_ACTIVE_HIGH>;
> > +		regulator-always-on;
> > +	};
> > +};
> 
> The VIO regulator is on the pdk2, so it should be in the PDK2 U-Boot extras.
> 
> > +&fec {
> > +	phy-reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
> > +	phy-reset-duration = <1>;
> > +	phy-reset-post-delay = <10>;
> 
> So is the PHY, so this should also be in the PDK2 extras.
> 
> (and it should be fixed in Linux too eventually, if it's not done yet)

I think Linux handles this a bit different:  The node for the PHY contains
almost the same properties already so I believe that is what's used in the
kernel:

	ethphy0: ethernet-phy at 0 {
		reg = <0>;
		max-speed = <100>;
		reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
		reset-delay-us = <1000>;
		reset-post-delay-us = <1000>;
	};

Not sure why U-Boot uses a different set of properties, maybe it makes
sense at some point to start using those instead.

Also, this was the reason why I put it into the general dhcom dtsi.  I was
thinking that, if the existing properties are this general, mine should
probably be, too.

> [...]

On 4/15/20 5:17 PM, Harald Seiler wrote:
> Hello Marek,
> 
> On Wed, 2020-04-15 at 16:53 +0200, Marek Vasut wrote:
>> On 4/15/20 4:48 PM, Harald Seiler wrote:
>>> Use DM_ETH instead of legacy networking.
>>
>> Some more descriptive commit message would help.
>>
>> [...]
>>
>>> diff --git a/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
>>> new file mode 100644
>>> index 000000000000..88840bb45920
>>> --- /dev/null
>>> +++ b/arch/arm/dts/imx6qdl-dhcom-u-boot.dtsi
>>> @@ -0,0 +1,22 @@
>>> +// SPDX-License-Identifier: (GPL-2.0+)
>>> +/*
>>> + * Copyright (C) 2020 Harald Seiler <hws at denx.de>
>>> + */
>>> +
>>> +/ {
>>> +	fec_vio: regulator-fec {
>>> +		compatible = "regulator-fixed";
>>> +
>>> +		regulator-name = "fec-vio";
>>> +		gpio = <&gpio1 7 GPIO_ACTIVE_HIGH>;
>>> +		regulator-always-on;
>>> +	};
>>> +};
>>
>> The VIO regulator is on the pdk2, so it should be in the PDK2 U-Boot extras.
>>
>>> +&fec {
>>> +	phy-reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
>>> +	phy-reset-duration = <1>;
>>> +	phy-reset-post-delay = <10>;
>>
>> So is the PHY, so this should also be in the PDK2 extras.
>>
>> (and it should be fixed in Linux too eventually, if it's not done yet)
> 
> I think Linux handles this a bit different:  The node for the PHY contains
> almost the same properties already so I believe that is what's used in the
> kernel:
> 
> 	ethphy0: ethernet-phy at 0 {
> 		reg = <0>;
> 		max-speed = <100>;
> 		reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
> 		reset-delay-us = <1000>;
> 		reset-post-delay-us = <1000>;
> 	};
> 
> Not sure why U-Boot uses a different set of properties, maybe it makes
> sense at some point to start using those instead.
> 
> Also, this was the reason why I put it into the general dhcom dtsi.  I was
> thinking that, if the existing properties are this general, mine should
> probably be, too.

I recently had a look into the MDIO subsystem in Linux and the reset
GPIO can be either MDIO-bus level OR PHY-level, so that's why there are
two sets of properties at different location. Look at:

linux-2.6$ git grep gpio.*reset drivers/net/phy/

I _think_ U-Boot only implements one of those two options, but I might
be wrong there.