On Wed, 10 Jun 2015 23:58:11 +0200
Alban <albeu@xxxxxxx> wrote:
> On Mon, 8 Jun 2015 13:17:58 +0300
> Antony Pavlov <antonynpavlov@xxxxxxxxx> wrote:
>
> > IMHO AR9132 SoC can't work without external oscilator.
> >
> > Can we just move basic extosc declaration to SoC dt file
> > (ar9132.dtsi)? So board dt file ar9132_tl_wr1043nd_v1.dts will
> > contain only oscilator clock frequency value.
>
> I would prefer to keep the split between the files in sync with the
> hardware. I understand that most simple board designs use a fixed
> oscillator, but that might not always be the case.
>
The AR9132 SoC __always__ use one external oscilator. So it's reasonable
to have the first mention of extosc in ar9132.dtsi not in a board file.
This description style is always sync with hardware.
On the other hand pll-controller is always part of the SoC
not a part of a board. So pll-controller on extosc dependency
have to go to SoC dts file not to a board file. In your dts description
pll-controller is a part of a dts board file.
It looks like my previous device tree structure proposal contains a small error
(extra clock-frequency field in ar9132.dtsi). I have fixed it. Please comment it.
ar9132.dtsi:
============
extosc: oscillator {
compatible = "fixed-clock";
#clock-cells = <0>;
};
...
ahb {
apb {
...
pll-controller@18050000 {
...
clocks = <&extosc>;
...
ar9132_tl_wr1043nd_v1.dts:
==========================
...
&extosc {
clock-frequency = <40000000>;
};
--
--
Best regards,
Antony Pavlov
