W dniu 2020-08-30 o 01:16, Andrew Lunn pisze:
I meant that with the split description of the mdio node the mdio bus for
use in the system would be selected almost automatically. Suppose that I can
do the device tree "my way":
&fec2 {
...
mdio { phy2 ... };
...
};
&fec1 {
...
mdio { phy1 ... };
...
};
This emphasizes which PHY is intended for use by which FEC, that's why it
looks more natural for me.
And it looks really wrong to me. It suggests there are two busses, and
each PHY is on its own bus. When in fact there is one MDIO bus with
two PHYs. Device tree should represents the real hardware, not some
pseudo description.
Andrew
Sure, the "split" variant may cause a misleading first impression for a
human reader. Similarly, one might argue that having both PHYs under one
mdio node suggests that both PHYs are connected to the same FEC. One way
or another, the device tree is a pretty complex thing and requires some
effort to read it correctly. The important thing is if the kernel is
getting the correct information.
The discussion got a bit off-topic, though. I'm not advocating any
particular structure of the device tree, nor I'm saying any should be
supported, as long the existing standard(s) make(s) it possible to do
their job(s).
Getting back to the original problem, I have tried the solution with
clocks defined under phy nodes, and it didn't work. eth0 was up, but
eth1 again faced "fec 2188000.ethernet eth1: Unable to connect to phy".
Details below, maybe it was my fault.
imx6ull.dtsi defines:
fec1: ethernet@2188000 {
compatible = "fsl,imx6ul-fec",
"fsl,imx6q-fec";
reg = <0x2188000 0x4000>;
interrupts = <GIC_SPI 118
IRQ_TYPE_LEVEL_HIGH>,
<GIC_SPI 119
IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks IMX6UL_CLK_ENET>,
<&clks IMX6UL_CLK_ENET_AHB>,
<&clks IMX6UL_CLK_ENET_PTP>,
<&clks IMX6UL_CLK_ENET_REF>,
<&clks IMX6UL_CLK_ENET_REF>;
clock-names = "ipg", "ahb", "ptp",
"enet_clk_ref", "enet_out";
stop-mode = <&gpr 0x10 3>;
fsl,num-tx-queues=<1>;
fsl,num-rx-queues=<1>;
fsl,magic-packet;
fsl,wakeup_irq = <0>;
status = "disabled";
};
fec2: ethernet@20b4000 {
compatible = "fsl,imx6ul-fec",
"fsl,imx6q-fec";
reg = <0x20b4000 0x4000>;
interrupts = <GIC_SPI 120
IRQ_TYPE_LEVEL_HIGH>,
<GIC_SPI 121
IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks IMX6UL_CLK_ENET>,
<&clks IMX6UL_CLK_ENET_AHB>,
<&clks IMX6UL_CLK_ENET_PTP>,
<&clks IMX6UL_CLK_ENET2_REF_125M>,
<&clks IMX6UL_CLK_ENET2_REF_125M>;
clock-names = "ipg", "ahb", "ptp",
"enet_clk_ref", "enet_out";
stop-mode = <&gpr 0x10 4>;
fsl,num-tx-queues=<1>;
fsl,num-rx-queues=<1>;
fsl,magic-packet;
fsl,wakeup_irq = <0>;
status = "disabled";
};
so in my top-level dts file (which includes imx6ull.dtsi) I've tried:
&fec1 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet1>;
phy-mode = "rmii";
phy-handle = <ðphy0>;
status = "okay";
};
&fec2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet2>, <&pinctrl_enet2_mdio>;
phy-mode = "rmii";
phy-handle = <ðphy1>;
status = "okay";
mdio {
#address-cells = <1>;
#size-cells = <0>;
ethphy0: ethernet-phy@0 {
reg = <0>;
clocks = <&clks IMX6UL_CLK_ENET_REF>;
};
ethphy1: ethernet-phy@1 {
reg = <1>;
clocks = <&clks IMX6UL_CLK_ENET2_REF_125M>;
};
};
};
Adding compatible = "..." and max-speed = "..." didn't change anything.
Please, let me know if I omitted something important in the test, and if
I should repeat it with amended device tree.
Best regards,
Adam
