Re: [PATCH 12/13] arm64: dts: add Allwinner A64 SoC .dtsi

[Andre Przywara <andre.przywara@arm.com>]

Hi Maxime,

On 26/07/16 21:30, Maxime Ripard wrote:
> From: Andre Przywara <andre.przywara@arm.com>
> 
> The Allwinner A64 SoC is a low-cost chip with 4 ARM Cortex-A53 cores
> and the typical tablet / TV box peripherals.
> The SoC is based on the (32-bit) Allwinner H3 chip, sharing most of
> the peripherals and the memory map.
> Although the cores are proper 64-bit ones, the whole SoC is actually
> limited to 4GB (including all the supported DRAM), so we use 32-bit
> address and size cells. This has the nice feature of us being able to
> reuse the DT for 32-bit kernels as well.
> This .dtsi lists the hardware that we support so far.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> Acked-by: Rob Herring <robh@kernel.org>
> [Maxime: Convert to CCU binding, drop the MMC support for now]
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> ---
>  Documentation/devicetree/bindings/arm/sunxi.txt |   1 +
>  MAINTAINERS                                     |   1 +
>  arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi   | 273 ++++++++++++++++++++++++
>  3 files changed, 275 insertions(+)
>  create mode 100644 arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> 
> diff --git a/Documentation/devicetree/bindings/arm/sunxi.txt b/Documentation/devicetree/bindings/arm/sunxi.txt
> index 7e79fcc36b0d..7e59d8ba86af 100644
> --- a/Documentation/devicetree/bindings/arm/sunxi.txt
> +++ b/Documentation/devicetree/bindings/arm/sunxi.txt
> @@ -14,3 +14,4 @@ using one of the following compatible strings:
>    allwinner,sun8i-a83t
>    allwinner,sun8i-h3
>    allwinner,sun9i-a80
> +  allwinner,sun50i-a64
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7304d2e37a98..440490126bfb 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -955,6 +955,7 @@ M:	Chen-Yu Tsai <wens@csie.org>
>  L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
>  S:	Maintained
>  N:	sun[x456789]i
> +F:	arch/arm64/boot/dts/allwinner/
>  
>  ARM/Allwinner SoC Clock Support
>  M:	Emilio López <emilio@elopez.com.ar>
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> new file mode 100644
> index 000000000000..636165d75373
> --- /dev/null
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> @@ -0,0 +1,273 @@
> +/*
> + * Copyright (C) 2016 ARM Ltd.
> + * based on the Allwinner H3 dtsi:
> + *    Copyright (C) 2015 Jens Kuske <jenskuske@gmail.com>
> + *
> + * This file is dual-licensed: you can use it either under the terms
> + * of the GPL or the X11 license, at your option. Note that this dual
> + * licensing only applies to this file, and not this project as a
> + * whole.
> + *
> + *  a) This file is free software; you can redistribute it and/or
> + *     modify it under the terms of the GNU General Public License as
> + *     published by the Free Software Foundation; either version 2 of the
> + *     License, or (at your option) any later version.
> + *
> + *     This file is distributed in the hope that it will be useful,
> + *     but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *     GNU General Public License for more details.
> + *
> + * Or, alternatively,
> + *
> + *  b) Permission is hereby granted, free of charge, to any person
> + *     obtaining a copy of this software and associated documentation
> + *     files (the "Software"), to deal in the Software without
> + *     restriction, including without limitation the rights to use,
> + *     copy, modify, merge, publish, distribute, sublicense, and/or
> + *     sell copies of the Software, and to permit persons to whom the
> + *     Software is furnished to do so, subject to the following
> + *     conditions:
> + *
> + *     The above copyright notice and this permission notice shall be
> + *     included in all copies or substantial portions of the Software.
> + *
> + *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
> + *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
> + *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
> + *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
> + *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
> + *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + *     OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#include <dt-bindings/clock/sun50i-a64-ccu.h>
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +#include <dt-bindings/pinctrl/sun4i-a10.h>
> +#include <dt-bindings/reset/sun50i-a64-ccu.h>
> +
> +/ {
> +	interrupt-parent = <&gic>;
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +
> +	cpus {
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +
> +		cpu@0 {
> +			compatible = "arm,cortex-a53", "arm,armv8";
> +			device_type = "cpu";
> +			reg = <0>;
> +			enable-method = "psci";
> +		};
> +
> +		cpu@1 {
> +			compatible = "arm,cortex-a53", "arm,armv8";
> +			device_type = "cpu";
> +			reg = <1>;
> +			enable-method = "psci";
> +		};
> +
> +		cpu@2 {
> +			compatible = "arm,cortex-a53", "arm,armv8";
> +			device_type = "cpu";
> +			reg = <2>;
> +			enable-method = "psci";
> +		};
> +
> +		cpu@3 {
> +			compatible = "arm,cortex-a53", "arm,armv8";
> +			device_type = "cpu";
> +			reg = <3>;
> +			enable-method = "psci";
> +		};
> +	};
> +
> +	psci {
> +		compatible = "arm,psci-0.2";
> +		method = "smc";
> +	};
> +
> +	timer {
> +		compatible = "arm,armv8-timer";
> +		interrupts = <GIC_PPI 13
> +			(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
> +			     <GIC_PPI 14
> +			(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
> +			     <GIC_PPI 11
> +			(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
> +			     <GIC_PPI 10
> +			(GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
> +	};

Can you add a PMU node here? Or shall I send a patch on top of it?
It would be:

	pmu {
        	compatible = "arm,cortex-a53-pmu", "arm,armv8-pmuv3";
		interrupts = <GIC_SPI 120 IRQ_TYPE_LEVEL_HIGH>,
			     <GIC_SPI 121 IRQ_TYPE_LEVEL_HIGH>,	
			     <GIC_SPI 122 IRQ_TYPE_LEVEL_HIGH>,
			     <GIC_SPI 123 IRQ_TYPE_LEVEL_HIGH>;
		interrupt-affinity = <&cpu0>,
				     <&cpu1>,
				     <&cpu2>,
				     <&cpu3>;
	};

This enables perf to use hardware counters (for cycles and instructions,
for instance).

> +
> +	clocks {
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		ranges;
> +
> +		osc24M: osc24M_clk {
> +			#clock-cells = <0>;
> +			compatible = "fixed-clock";
> +			clock-frequency = <24000000>;
> +			clock-output-names = "osc24M";
> +		};
> +
> +		osc32k: osc32k_clk {
> +			#clock-cells = <0>;
> +			compatible = "fixed-clock";
> +			clock-frequency = <32768>;
> +			clock-output-names = "osc32k";
> +		};
> +	};

Can you remove this "clocks" node and put the two subnodes directly onto
the top level?
I know that putting clocks into a subnode is quite wide spread, but it
does not represent any hardware hierarchy, especially in this
fixed-clock case.
So if we can (and it is easy here!) we should avoid any clocks subnode.

(Yes, I know that this was in my original DT as well, but Mark Rutland
convinced me of this.)

Cheers,
Andre.

> +
> +	soc {
> +		compatible = "simple-bus";
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		ranges;
> +
> +		ccu: clock@01c20000 {
> +			compatible = "allwinner,sun50i-a64-ccu";
> +			reg = <0x01c20000 0x400>;
> +			clocks = <&osc24M>, <&osc32k>;
> +			clock-names = "hosc", "losc";
> +			#clock-cells = <1>;
> +			#reset-cells = <1>;
> +		};
> +
> +		pio: pinctrl@1c20800 {
> +			compatible = "allwinner,sun50i-a64-pinctrl";
> +			reg = <0x01c20800 0x400>;
> +			interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 17 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&ccu CLK_A64_BUS_PIO>;
> +			gpio-controller;
> +			#gpio-cells = <3>;
> +			interrupt-controller;
> +			#interrupt-cells = <2>;
> +
> +			i2c1_pins: i2c1_pins {
> +				allwinner,pins = "PH2", "PH3";
> +				allwinner,function = "i2c1";
> +				allwinner,drive = <SUN4I_PINCTRL_10_MA>;
> +				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
> +			};
> +
> +			uart0_pins_a: uart0@0 {
> +				allwinner,pins = "PB8", "PB9";
> +				allwinner,function = "uart0";
> +				allwinner,drive = <SUN4I_PINCTRL_10_MA>;
> +				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
> +			};
> +		};
> +
> +		uart0: serial@1c28000 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x01c28000 0x400>;
> +			interrupts = <GIC_SPI 0 IRQ_TYPE_LEVEL_HIGH>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&ccu CLK_A64_BUS_UART0>;
> +			resets = <&ccu RST_A64_BUS_UART0>;
> +			status = "disabled";
> +		};
> +
> +		uart1: serial@1c28400 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x01c28400 0x400>;
> +			interrupts = <GIC_SPI 1 IRQ_TYPE_LEVEL_HIGH>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&ccu CLK_A64_BUS_UART1>;
> +			resets = <&ccu RST_A64_BUS_UART1>;
> +			status = "disabled";
> +		};
> +
> +		uart2: serial@1c28800 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x01c28800 0x400>;
> +			interrupts = <GIC_SPI 2 IRQ_TYPE_LEVEL_HIGH>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&ccu CLK_A64_BUS_UART2>;
> +			resets = <&ccu RST_A64_BUS_UART2>;
> +			status = "disabled";
> +		};
> +
> +		uart3: serial@1c28c00 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x01c28c00 0x400>;
> +			interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&ccu CLK_A64_BUS_UART3>;
> +			resets = <&ccu RST_A64_BUS_UART3>;
> +			status = "disabled";
> +		};
> +
> +		uart4: serial@1c29000 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x01c29000 0x400>;
> +			interrupts = <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&ccu CLK_A64_BUS_UART4>;
> +			resets = <&ccu RST_A64_BUS_UART4>;
> +			status = "disabled";
> +		};
> +
> +		rtc: rtc@1f00000 {
> +			compatible = "allwinner,sun6i-a31-rtc";
> +			reg = <0x01f00000 0x54>;
> +			interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
> +		};
> +
> +		i2c0: i2c@1c2ac00 {
> +			compatible = "allwinner,sun6i-a31-i2c";
> +			reg = <0x01c2ac00 0x400>;
> +			interrupts = <GIC_SPI 6 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&ccu CLK_A64_BUS_I2C0>;
> +			resets = <&ccu RST_A64_BUS_I2C0>;
> +			status = "disabled";
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +		};
> +
> +		i2c1: i2c@1c2b000 {
> +			compatible = "allwinner,sun6i-a31-i2c";
> +			reg = <0x01c2b000 0x400>;
> +			interrupts = <GIC_SPI 7 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&ccu CLK_A64_BUS_I2C1>;
> +			resets = <&ccu RST_A64_BUS_I2C1>;
> +			status = "disabled";
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +		};
> +
> +		i2c2: i2c@1c2b400 {
> +			compatible = "allwinner,sun6i-a31-i2c";
> +			reg = <0x01c2b400 0x400>;
> +			interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&ccu CLK_A64_BUS_I2C2>;
> +			resets = <&ccu RST_A64_BUS_I2C2>;
> +			status = "disabled";
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +		};
> +
> +		gic: interrupt-controller@1c81000 {
> +			compatible = "arm,gic-400";
> +			reg = <0x01c81000 0x1000>,
> +			      <0x01c82000 0x2000>,
> +			      <0x01c84000 0x2000>,
> +			      <0x01c86000 0x2000>;
> +			interrupts = <GIC_PPI 9 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
> +			interrupt-controller;
> +			#interrupt-cells = <3>;
> +		};
> +	};
> +};
>