Re: [linux-sunxi] Re: [PATCH 1/3] ARM: dts: sun8i: Add basic dtsi file for Allwinner R40

[icenowy@aosc.io]

在 2017-08-24 14:07，Maxime Ripard 写道：
> On Wed, Aug 23, 2017 at 11:13:04PM +0800, icenowy@aosc.io wrote:
>> 在 2017-08-23 22:35，Maxime Ripard 写道：
>> > On Wed, Aug 23, 2017 at 07:56:29PM +0800, icenowy@aosc.io wrote:
>> > > > > +			reg = <0x01c0f000 0x1000>;
>> > > > > +			clocks = <&ccu CLK_BUS_MMC0>, <&ccu CLK_MMC0>;
>> > > > > +			clock-names = "ahb", "mmc";
>> > > > > +			resets = <&ccu RST_BUS_MMC0>;
>> > > > > +			reset-names = "ahb";
>> > > > > +			pinctrl-0 = <&mmc0_pins>;
>> > > > > +			pinctrl-names = "default";
>> > > > > +			interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
>> > > > > +			max-frequency = <150000000>;
>> > > >
>> > > > have you tested that frequency?
>> > >
>> > > I think the frequency should be kept here, although my cards cannot
>> > > reach this frequency.
>> > >
>> > > The numbers are same as the corresponding controllers in A64.
>> > >
>> > > Maybe I should add a comment saying it's educated guess?
>> >
>> > I'd rather have it tested by someone, and then add the proper
>> > frequencies. It took quite a while to figure out how these modes were
>> > supposed to be working on the A64, so it's not obvious that they're
>> > just going to work.
>> 
>> Should I add my results here?
>> 
>> MMC0: 25MHz
>> MMC1: 50MHz
>> MMC2: 52MHz
>> MMC3: not wired :-(
>> 
>> I think it's conservative enough and works well ;-)
> 
> And that's my point. You didn't test HS200, SDR50 or SDR104 for
> example. So you have no idea whether the frequencies from 50MHz to
> 150MHz are actually working or not.

OK.

I will leave a TODO here, although I cannot measure the frequencies
with Banana Pis -- it will requires custom boards.

> 
>> 
>> >
>> > > > > +		gic: interrupt-controller@1c81000 {
>> > > > > +			compatible = "arm,gic-400";
>> > > > > +			reg = <0x01c81000 0x1000>,
>> > > > > +			      <0x01c82000 0x1000>,
>> > > > > +			      <0x01c84000 0x2000>,
>> > > > > +			      <0x01c86000 0x2000>;
>> > > > > +			interrupt-controller;
>> > > > > +			#interrupt-cells = <3>;
>> > > > > +			interrupts = <GIC_PPI 9 (GIC_CPU_MASK_SIMPLE(4) |
>> > > > > IRQ_TYPE_LEVEL_HIGH)>;
>> > > > > +		};
>> > > > > +	};
>> > > > > +
>> > > > > +	timer {
>> > > > > +		compatible = "arm,armv7-timer";
>> > > > > +		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) |
>> > > > > IRQ_TYPE_LEVEL_LOW)>,
>> > > > > +			     <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
>> > > > > +			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
>> > > > > +			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
>> > > >
>> > > > Those masks are wrong.
>> > >
>> > > I compared it with other sun8i SoCs' device tree.
>> > >
>> > > Where's wrong?
>> >
>> > It's supposed to be a mask of the CPUs in your system. Since you just
>> > have one of them, it shouldn't be 4.
>> 
>> R40 has 4 cores...
>> 
>> Or I didn't understand this?
> 
> Gah, sorry, I mistook this for the V3s for some reason...

Thanks.

I think I should send a fix for V3s.

> 
> Maxime
> 
> --
> Maxime Ripard, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com