Re: [PATCH v2 06/10] ARM: suniv: add USB-related device nodes

Icenowy Zheng
2022-10-24T14:57:28Z

在 2022-10-24星期一的 15:16 +0100，Andre Przywara写道：
> On Wed, 12 Oct 2022 13:55:58 +0800
> Icenowy Zheng <uwu@icenowy.me> wrote:
>
> Hi,
>
> > The suniv SoC has a USB OTG controller and a USB PHY like other
> > Allwinner SoCs.
> >
> > Add their device tree node.
>
> Looks alright to me, checked against the manual, also compared
> against
> some other Allwinner USB DT nodes. Also passes the binding and DTB
> checks.
>
> Just one small question below, but nevertheless:
>
> Reviewed-by: Andre Przywara <andre.przywara@arm.com>
>
> > Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
> > ---
> > No changes since v1.
> >
> >  arch/arm/boot/dts/suniv-f1c100s.dtsi | 26
> > ++++++++++++++++++++++++++
> >  1 file changed, 26 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/suniv-f1c100s.dtsi
> > b/arch/arm/boot/dts/suniv-f1c100s.dtsi
> > index 0edc1724407b..a01541ba42c5 100644
> > --- a/arch/arm/boot/dts/suniv-f1c100s.dtsi
> > +++ b/arch/arm/boot/dts/suniv-f1c100s.dtsi
> > @@ -133,6 +133,32 @@ mmc1: mmc@1c10000 {
> >                         #size-cells = <0>;
> >                 };
> >
> > +               usb_otg: usb@1c13000 {
> > +                       compatible = "allwinner,suniv-f1c100s-
> > musb";
> > +                       reg = <0x01c13000 0x0400>;
> > +                       clocks = <&ccu CLK_BUS_OTG>;
> > +                       resets = <&ccu RST_BUS_OTG>;
> > +                       interrupts = <26>;
> > +                       interrupt-names = "mc";
> > +                       phys = <&usbphy 0>;
> > +                       phy-names = "usb";
> > +                       extcon = <&usbphy 0>;
> > +                       allwinner,sram = <&otg_sram 1>;
>
> What is this "1" for? I see it all over the other Allwinner SRAM
> properties, but can't find any documentation about that number, nor
> can I
> see that it would be used in the code.

It means mapping the SRAM to dedicated device instead of CPU.

This information is available in previous sunxi-sram.txt binding, but
lost when converting to json schema, maybe because it does not fit well
in json schema.

>
> Does anyone know?
>
> Cheers,
> Andre
>
> > +                       status = "disabled";
> > +               };
> > +
> > +               usbphy: phy@1c13400 {
> > +                       compatible = "allwinner,suniv-f1c100s-usb-
> > phy";
> > +                       reg = <0x01c13400 0x10>;
> > +                       reg-names = "phy_ctrl";
> > +                       clocks = <&ccu CLK_USB_PHY0>;
> > +                       clock-names = "usb0_phy";
> > +                       resets = <&ccu RST_USB_PHY0>;
> > +                       reset-names = "usb0_reset";
> > +                       #phy-cells = <1>;
> > +                       status = "disabled";
> > +               };
> > +
> >                 ccu: clock@1c20000 {
> >                         compatible = "allwinner,suniv-f1c100s-ccu";
> >                         reg = <0x01c20000 0x400>;