Re: [PATCH v4 12/12] MIPS: Add basic support for the TL-WR1043ND version 1

From: Antony Pavlov
Date: Mon Jun 15 2015 - 03:36:19 EST


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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/