Re: [PATCH 3/4] arm64: dts: Add mediatek MT8173 SoC and evaluation board dts and Makefile

[Eddie Huang <eddie.huang@mediatek.com>]

On Wed, 2014-12-10 at 15:50 +0100, Matthias Brugger wrote:
> 2014-12-10 15:27 GMT+01:00 Yingjoe Chen <yingjoe.chen@mediatek.com>:
> >
> > Hi,
> >
> > On Wed, 2014-12-10 at 18:50 +0800, Eddie Huang wrote:
> > <...>
> >> diff --git a/arch/arm64/boot/dts/mt8173-evb.dts b/arch/arm64/boot/dts/mt8173-evb.dts
> >> new file mode 100644
> >> index 0000000..adf26dd
> >> --- /dev/null
> >> +++ b/arch/arm64/boot/dts/mt8173-evb.dts
> > <...>
> >> +     timer {
> >> +             compatible = "arm,armv8-timer";
> >> +             interrupt-parent = <&gic>;
> >> +             interrupts = <1 13 0x8>,
> >> +                          <1 14 0x8>,
> >> +                          <1 11 0x8>,
> >> +                          <1 10 0x8>;
> >> +             clock-frequency = <13000000>;
> >
> > I believe our firmware doesn't need this line. Please remove it.
> 
> The point here would be to know if you need to enable a special timer
> from the mtk-timer block to get the arch timer working.
> In any case, you will need some sort of timer. This dts does not
> describe the mtk-timer (may in the mt8173 it does not exist) but
> defines the clocks clk26m and clk32k. So if you don't use the
> mtk-timer, please remove the clocks as there isn't a block using them.
> 

MT8173 has two timer set: CPUGPT and APBGPT, and use CPUGPT to enable
arch_timer. Previous series only have APBGPT. MT8173 still need enable
CPUGPT to get arch timer working, we put this in loader, and transparent
to kernel. So I will remove clk26m and clk32k in next version.