LinuxLists.cc - [PATCH v3] ARM: dts: imx6sx-sdb: Fix enet phy regulator

2018-10-08 15:28:52

Subject: [PATCH v3] ARM: dts: imx6sx-sdb: Fix enet phy regulator

Bindings for "fixed-regulator" only explicitly support "gpio" property,
not "gpios". Fix by correcting the property name.

The enet PHYs on imx6sx-sdb needs to be explicitly reset after a power
cycle, this can be handled by the phy-reset-gpios property. Sadly this
is not handled on suspend: the fec driver turns phy-supply off but
doesn't assert phy-reset-gpios again on resume.

Since additional phy-level work is required to support powering off the
phy in suspend fix the problem by just marking the regulator as
"boot-on" "always-on" so that it's never turned off. This behavior is
equivalent to older releases.

Keep the phy-reset-gpios property on fec anyway because it is a correct
description of board design.

This issue was exposed by commit efdfeb079cc3 ("regulator: fixed:
Convert to use GPIO descriptor only") which causes the "gpios" property
to also be parsed. Before that commit the "gpios" property had no
effect, PHY reset was only handled in the the bootloader.

This fixes linux-next boot failures previously reported here:
https://lore.kernel.org/patchwork/patch/982437/#1177900
https://lore.kernel.org/patchwork/patch/994091/#1178304

Signed-off-by: Leonard Crestez <[email protected]>

---
I attempted to fix by asserting phy-reset-gpios on resume but apparently
phy fixups are still lost and need to be reapplied (not sure why/how).

Changes since v2:
* Mark as always-on boot-enable-on because phy power cycling is hard
* Clear Reviewed-by because of large behavior change
* Link to v2: https://lore.kernel.org/patchwork/patch/995520/

Changes since v1:
* Use 0x10b0 for phy reset pinctrl value (Fabio)
* Link to v1: https://lore.kernel.org/patchwork/patch/994871/

arch/arm/boot/dts/imx6sx-sdb.dtsi | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/imx6sx-sdb.dtsi b/arch/arm/boot/dts/imx6sx-sdb.dtsi
index 53b3408b5fab..7d7d679945d2 100644
--- a/arch/arm/boot/dts/imx6sx-sdb.dtsi
+++ b/arch/arm/boot/dts/imx6sx-sdb.dtsi
@@ -115,11 +115,13 @@
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet_3v3>;
regulator-name = "enet_3v3";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
- gpios = <&gpio2 6 GPIO_ACTIVE_LOW>;
+ gpio = <&gpio2 6 GPIO_ACTIVE_LOW>;
+ regulator-boot-on;
+ regulator-always-on;
};

reg_pcie_gpio: regulator-pcie-gpio {
compatible = "regulator-fixed";
pinctrl-names = "default";
@@ -178,10 +180,11 @@
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet1>;
phy-supply = <&reg_enet_3v3>;
phy-mode = "rgmii";
phy-handle = <&ethphy1>;
+ phy-reset-gpios = <&gpio2 7 GPIO_ACTIVE_LOW>;
status = "okay";

mdio {
#address-cells = <1>;
#size-cells = <0>;
@@ -371,10 +374,12 @@
MX6SX_PAD_RGMII1_RD1__ENET1_RX_DATA_1 0x3081
MX6SX_PAD_RGMII1_RD2__ENET1_RX_DATA_2 0x3081
MX6SX_PAD_RGMII1_RD3__ENET1_RX_DATA_3 0x3081
MX6SX_PAD_RGMII1_RX_CTL__ENET1_RX_EN 0x3081
MX6SX_PAD_ENET2_RX_CLK__ENET2_REF_CLK_25M 0x91
+ /* phy reset */
+ MX6SX_PAD_ENET2_CRS__GPIO2_IO_7 0x10b0
>;
};

pinctrl_enet_3v3: enet3v3grp {
fsl,pins = <
--
2.17.1

2018-10-09 01:11:23

by Shawn Guo

[permalink] [raw]

Subject: Re: [PATCH v3] ARM: dts: imx6sx-sdb: Fix enet phy regulator

On Mon, Oct 08, 2018 at 03:28:01PM +0000, Leonard Crestez wrote:
> Bindings for "fixed-regulator" only explicitly support "gpio" property,
> not "gpios". Fix by correcting the property name.
>
> The enet PHYs on imx6sx-sdb needs to be explicitly reset after a power
> cycle, this can be handled by the phy-reset-gpios property. Sadly this
> is not handled on suspend: the fec driver turns phy-supply off but
> doesn't assert phy-reset-gpios again on resume.
>
> Since additional phy-level work is required to support powering off the
> phy in suspend fix the problem by just marking the regulator as
> "boot-on" "always-on" so that it's never turned off. This behavior is
> equivalent to older releases.
>
> Keep the phy-reset-gpios property on fec anyway because it is a correct
> description of board design.
>
> This issue was exposed by commit efdfeb079cc3 ("regulator: fixed:
> Convert to use GPIO descriptor only") which causes the "gpios" property
> to also be parsed. Before that commit the "gpios" property had no
> effect, PHY reset was only handled in the the bootloader.
>
> This fixes linux-next boot failures previously reported here:
> https://lore.kernel.org/patchwork/patch/982437/#1177900
> https://lore.kernel.org/patchwork/patch/994091/#1178304

So this is a fix we only need to apply for 4.20-rc, right?

Shawn

>
> Signed-off-by: Leonard Crestez <[email protected]>
>
> ---
> I attempted to fix by asserting phy-reset-gpios on resume but apparently
> phy fixups are still lost and need to be reapplied (not sure why/how).
>
> Changes since v2:
> * Mark as always-on boot-enable-on because phy power cycling is hard
> * Clear Reviewed-by because of large behavior change
> * Link to v2: https://lore.kernel.org/patchwork/patch/995520/
>
> Changes since v1:
> * Use 0x10b0 for phy reset pinctrl value (Fabio)
> * Link to v1: https://lore.kernel.org/patchwork/patch/994871/
>
> arch/arm/boot/dts/imx6sx-sdb.dtsi | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/imx6sx-sdb.dtsi b/arch/arm/boot/dts/imx6sx-sdb.dtsi
> index 53b3408b5fab..7d7d679945d2 100644
> --- a/arch/arm/boot/dts/imx6sx-sdb.dtsi
> +++ b/arch/arm/boot/dts/imx6sx-sdb.dtsi
> @@ -115,11 +115,13 @@
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_enet_3v3>;
> regulator-name = "enet_3v3";
> regulator-min-microvolt = <3300000>;
> regulator-max-microvolt = <3300000>;
> - gpios = <&gpio2 6 GPIO_ACTIVE_LOW>;
> + gpio = <&gpio2 6 GPIO_ACTIVE_LOW>;
> + regulator-boot-on;
> + regulator-always-on;
> };
>
> reg_pcie_gpio: regulator-pcie-gpio {
> compatible = "regulator-fixed";
> pinctrl-names = "default";
> @@ -178,10 +180,11 @@
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_enet1>;
> phy-supply = <&reg_enet_3v3>;
> phy-mode = "rgmii";
> phy-handle = <&ethphy1>;
> + phy-reset-gpios = <&gpio2 7 GPIO_ACTIVE_LOW>;
> status = "okay";
>
> mdio {
> #address-cells = <1>;
> #size-cells = <0>;
> @@ -371,10 +374,12 @@
> MX6SX_PAD_RGMII1_RD1__ENET1_RX_DATA_1 0x3081
> MX6SX_PAD_RGMII1_RD2__ENET1_RX_DATA_2 0x3081
> MX6SX_PAD_RGMII1_RD3__ENET1_RX_DATA_3 0x3081
> MX6SX_PAD_RGMII1_RX_CTL__ENET1_RX_EN 0x3081
> MX6SX_PAD_ENET2_RX_CLK__ENET2_REF_CLK_25M 0x91
> + /* phy reset */
> + MX6SX_PAD_ENET2_CRS__GPIO2_IO_7 0x10b0
> >;
> };
>
> pinctrl_enet_3v3: enet3v3grp {
> fsl,pins = <
> --
> 2.17.1
>

2018-10-09 23:00:43

by Leonard Crestez

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Subject: Re: [PATCH v3] ARM: dts: imx6sx-sdb: Fix enet phy regulator

On Tue, 2018-10-09 at 09:09 +0800, Shawn Guo wrote:
> On Mon, Oct 08, 2018 at 03:28:01PM +0000, Leonard Crestez wrote:
> > Bindings for "fixed-regulator" only explicitly support "gpio" property,
> > not "gpios". Fix by correcting the property name.
> >
> > The enet PHYs on imx6sx-sdb needs to be explicitly reset after a power
> > cycle, this can be handled by the phy-reset-gpios property. Sadly this
> > is not handled on suspend: the fec driver turns phy-supply off but
> > doesn't assert phy-reset-gpios again on resume.
> >
> > Since additional phy-level work is required to support powering off the
> > phy in suspend fix the problem by just marking the regulator as
> > "boot-on" "always-on" so that it's never turned off. This behavior is
> > equivalent to older releases.
> >
> > Keep the phy-reset-gpios property on fec anyway because it is a correct
> > description of board design.
> >
> > This issue was exposed by commit efdfeb079cc3 ("regulator: fixed:
> > Convert to use GPIO descriptor only") which causes the "gpios" property
> > to also be parsed. Before that commit the "gpios" property had no
> > effect, PHY reset was only handled in the the bootloader.

> So this is a fix we only need to apply for 4.20-rc, right?

Yes.

This issue was exposed by gpio changes for 4.20 but 4.19 RCs are fine.

--
Regards,
Leonard

2018-11-05 02:19:50

by Shawn Guo

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