RE: Re: [PATCH v1 1/2] arm64: dts: mt7622: add some misc device nodes

Ryder Lee
2018-07-31T08:43:53Z

Hi Matthias,

Sorry for the late reply.

On Tue, 2018-07-31 at 16:17 +0800, Ryder Lee (李庚諺) wrote:
> Hi Ryder,
>
> On 16/07/18 16:59, Ryder Lee wrote:
> > Add some misc nodes support - timer and ARM CCI-400.
> >
> > Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
> > ---
> > arch/arm64/boot/dts/mediatek/mt7622.dtsi | 36
> > ++++++++++++++++++++++++++++++++
> > 1 file changed, 36 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > index 9213c96..8cdec52 100644
> > --- a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > +++ b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > @@ -217,6 +217,16 @@
> > #reset-cells = <1>;
> > };
> >
> > + timer: timer@10004000 {
> > + compatible = "mediatek,mt7622-timer",
> > + "mediatek,mt6577-timer";
> > + reg = <0 0x10004000 0 0x80>;
> > + interrupts = <GIC_SPI 152 IRQ_TYPE_LEVEL_LOW>;
> > + clocks = <&infracfg CLK_INFRA_APXGPT_PD>,
> > + <&topckgen CLK_TOP_RTC>;
> > + clock-names = "system-clk", "rtc-clk";
> > + };
> > +
> > scpsys: scpsys@10006000 {
> > compatible = "mediatek,mt7622-scpsys",
> > "syscon";
> > @@ -317,6 +327,32 @@
> > <0 0x10360000 0 0x2000>;
> > };
> >
> > + cci: cci@10390000 {
> > + compatible = "arm,cci-400";
> > + #address-cells = <1>;
> > + #size-cells = <1>;
> > + reg = <0 0x10390000 0 0x1000>;
> > + ranges = <0 0 0x10390000 0x10000>;
>
> From my understanding of the binding description ranges should hold child address, parent address and size of the region in the child address space. I can see in arch/arm64 two different variants using 4 ranges values (like here) and using three values.
>
> @Rob + Will what is the preferred way to describe this?

Hmmm... it's just a copy-paste (I take zynqmp.dtsi as an example).
> > +
> > + cci_control0: slave-if@1000 {
> > + compatible = "arm,cci-400-ctrl-if";
> > + interface-type = "ace-lite";
> > + reg = <0x1000 0x1000>;
> > + };
>
> Don't we need to add phandles to the cci-control-port property in the cpu nodes?
>
> Regards,
> Matthias

MT7622 use cci-400 to improve performance (DMA IO coherence) for
high-speed IPs. (i.e., ETH/WIFI/SATA/...)

I added it early but actually the related features have not supported in
mainline yet.

Ryder