Re: [PATCH v7 2/3] arm: dts: add Nuvoton NPCM750 device tree

From: Brendan Higgins
Date: Thu Nov 16 2017 - 21:51:02 EST

Sorry for the delay. I thought all of the comments were straightforward, but
there are a couple which need some further discussion.

On Fri, Oct 20, 2017 at 12:45 PM, Rob Herring <robh+dt@xxxxxxxxxx> wrote:
> On Thu, Oct 19, 2017 at 5:50 PM, Brendan Higgins
> <brendanhiggins@xxxxxxxxxx> wrote:
>> Add a common device tree for all Nuvoton NPCM750 BMCs and a board
>> specific device tree for the NPCM750 (Poleg) evaluation board.
>>
>> Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
>> Reviewed-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
>> Reviewed-by: Avi Fishman <avifishman70@xxxxxxxxx>
>> Reviewed-by: Joel Stanley <joel@xxxxxxxxx>
>> Tested-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
>> Tested-by: Avi Fishman <avifishman70@xxxxxxxxx>
>> ---
>
> [...]
>
>> diff --git a/arch/arm/boot/dts/nuvoton-npcm750.dtsi b/arch/arm/boot/dts/nuvoton-npcm750.dtsi
>> new file mode 100644
>> index 000000000000..85506b3cdd39
>> --- /dev/null
>> +++ b/arch/arm/boot/dts/nuvoton-npcm750.dtsi
>> @@ -0,0 +1,198 @@
>> +/*
>> + * DTSi file for the NPCM750 SoC
>> + *
>> + * Copyright 2012 Tomer Maimon <tomer.maimon@xxxxxxxxxxx>
>> + *
>> + * The code contained herein is licensed under the GNU General Public
>> + * License. You may obtain a copy of the GNU General Public License
>> + * Version 2 or later at the following locations:
>> + *
>> + * http://www.opensource.org/licenses/gpl-license.html
>> + * http://www.gnu.org/copyleft/gpl.html
>> + */
>> +
>> +#include <dt-bindings/interrupt-controller/arm-gic.h>
>> +#include <dt-bindings/clock/nuvoton,npcm7xx-clks.h>
>> +
>> +/ {
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + interrupt-parent = <&gic>;
>> +
>> + cpus {
>> + #address-cells = <1>;
>> + #size-cells = <0>;
>> + enable-method = "nuvoton,npcm7xx-smp";
>> +
>> + cpu@0 {
>> + device_type = "cpu";
>> + compatible = "arm,cortex-a9";
>> + clocks = <&clk NPCM7XX_CLK_CPU>;
>> + clock-names = "clk_cpu";
>> + reg = <0>;
>> + next-level-cache = <&l2>;
>> + };
>> +
>> + cpu@1 {
>> + device_type = "cpu";
>> + compatible = "arm,cortex-a9";
>> + clocks = <&clk NPCM7XX_CLK_CPU>;
>> + clock-names = "clk_cpu";
>> + reg = <1>;
>> + next-level-cache = <&l2>;
>> + };
>> + };
>> +
>> +/* external clock signal rg1refck, supplied by the phy */
>> +clk-rg1refck {
>> + compatible = "fixed-clock";
>> + #clock-cells = <0>;
>> + clock-frequency = <125000000>;
>> +};
>> +
>> +/* external clock signal rg2refck, supplied by the phy */
>> +clk-rg2refck {
>> + compatible = "fixed-clock";
>> + #clock-cells = <0>;
>> + clock-frequency = <125000000>;
>> +};
>> +
>> +clk-xin {
>> + compatible = "fixed-clock";
>> + #clock-cells = <0>;
>> + clock-frequency = <50000000>;
>> +};
>> +
>> + soc {
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + compatible = "simple-bus";
>> + interrupt-parent = <&gic>;
>> + ranges = <0x0 0xf0000000 0x00900000>;
>> +
>> + gcr: gcr@f0800000 {
>
> Should be gcr@800000. Build the dtb with W=1 and it will give you
> warnings for this.
>
>> + compatible = "nuvoton,npcm750-gcr", "syscon",
>> + "simple-mfd";
>> + reg = <0x800000 0x1000>;
>> + };
>> +
>> + scu: scu@f03fe000 {
>> + compatible = "arm,cortex-a9-scu";
>> + reg = <0x3fe000 0x1000>;
>> + };
>> +
>> + l2: cache-controller@f03fc000 {
>> + compatible = "arm,pl310-cache";
>> + reg = <0x3fc000 0x1000>;
>> + interrupts = <0 21 4>;
>> + cache-unified;
>> + cache-level = <2>;
>> + clocks = <&clk NPCM7XX_CLK_AXI>;
>> + };
>> +
>> + gic: interrupt-controller@f03ff000 {
>> + compatible = "arm,cortex-a9-gic";
>> + interrupt-controller;
>> + #interrupt-cells = <3>;
>> + reg = <0x3ff000 0x1000>,
>> + <0x3fe100 0x100>;
>> + };
>> +
>> + timer@f03fe600 {
>> + compatible = "arm,cortex-a9-twd-timer";
>> + reg = <0x3fe600 0x20>;
>> + interrupts = <1 13 0x304>;
>> + clocks = <&clk NPCM7XX_CLK_TIMER>;
>> + };
>> + };
>> +
>> + ahb {
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + compatible = "simple-bus";
>> + interrupt-parent = <&gic>;
>> + ranges = <0x80000000 0x80000000 0x40010000
>> + 0xe0800000 0xe0800000 0x0f800000
>> + 0x00000000 0xf0000000 0x00900000
>> + 0xf8000000 0xf8000000 0x02000000
>> + 0xfb000000 0xfb000000 0x00002000>;
>
> Just do "ranges;" here if all the translation is at the next level down.

Actually we do have some peripherals that sit directly on the AHB, they
just have not had their DTS nodes written yet. I counted at least 6
devices which probably won't get a sub-memory space.

>
> Sorry, it's hard to say exactly what to do without knowing the whole memory map.

No problem. Let me see if I can get it for you.

>
>> +
>> + clk: clock-controller@f0801000 {
>
> Seems like this belongs under /soc based on the address.

No, the AHB memory space is discontiguous. The "Cortex A9 Included" space
(/soc here) sits in one of the discontinuities.

>
>> + compatible = "nuvoton,npcm750-clk";
>> + #clock-cells = <1>;
>> + reg = <0x801000 0x1000>;
>> + status = "okay";
>> + };
>> +
>> + apb {
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + compatible = "simple-bus";
>> + interrupt-parent = <&gic>;
>> + ranges = <0x0 0x0 0x00300000>;
>
> And then this would be "<0x0 0xf0000000 0x300000>".
>
>> +
>> + timer0: timer@f0000000 {
>> + compatible = "nuvoton,npcm750-timer";
>> + interrupts = <0 32 4>;
>> + reg = <0x0 0x1000>;
>> + clocks = <&clk NPCM7XX_CLK_TIMER>;
>> + };
>> +
>> + watchdog0: watchdog@f0008000 {
>> + compatible = "nuvoton,npcm750-wdt";
>> + interrupts = <0 47 4>;
>> + reg = <0x8000 0x1000>;
>> + status = "disabled";
>> + clocks = <&clk NPCM7XX_CLK_TIMER>;
>> + };
>> +
>> + watchdog1: watchdog@f0009000 {
>> + compatible = "nuvoton,npcm750-wdt";
>> + interrupts = <0 48 4>;
>> + reg = <0x9000 0x1000>;
>> + status = "disabled";
>> + clocks = <&clk NPCM7XX_CLK_TIMER>;
>> + };
>> +
>> + watchdog2: watchdog@f000a000 {
>> + compatible = "nuvoton,npcm750-wdt";
>> + interrupts = <0 49 4>;
>> + reg = <0xa000 0x1000>;
>> + status = "disabled";
>> + clocks = <&clk NPCM7XX_CLK_TIMER>;
>> + };
>> +
>> + serial0: serial@f0001000 {
>> + compatible = "nuvoton,npcm750-uart";
>> + reg = <0x1000 0x1000>;
>> + clocks = <&clk NPCM7XX_CLK_UART_CORE>;
>> + interrupts = <0 2 4>;
>> + status = "disabled";
>> + };
>> +
>> + serial1: serial@f0002000 {
>> + compatible = "nuvoton,npcm750-uart";
>> + reg = <0x2000 0x1000>;
>> + clocks = <&clk NPCM7XX_CLK_UART_CORE>;
>> + interrupts = <0 3 4>;
>> + status = "disabled";
>> + };
>> +
>> + serial2: serial@f0003000 {
>> + compatible = "nuvoton,npcm750-uart";
>> + reg = <0x3000 0x1000>;
>> + clocks = <&clk NPCM7XX_CLK_UART_CORE>;
>> + interrupts = <0 4 4>;
>> + status = "disabled";
>> + };
>> +
>> + serial3: serial@f0004000 {
>> + compatible = "nuvoton,npcm750-uart";
>> + reg = <0x4000 0x1000>;
>> + clocks = <&clk NPCM7XX_CLK_UART_CORE>;
>> + interrupts = <0 5 4>;
>> + status = "disabled";
>> + };
>> + };
>> + };
>> +};
>> diff --git a/include/dt-bindings/clock/nuvoton,npcm7xx-clks.h b/include/dt-bindings/clock/nuvoton,npcm7xx-clks.h
>> new file mode 100644
>> index 000000000000..c69d3bbf7e42
>> --- /dev/null
>> +++ b/include/dt-bindings/clock/nuvoton,npcm7xx-clks.h
>> @@ -0,0 +1,39 @@
>> +/*
>> + * Copyright (C) 2016 Nuvoton Technologies, tali.perry@xxxxxxxxxxx
>> + *
>> + * This software is licensed under the terms of the GNU General Public
>> + * License version 2, as published by the Free Software Foundation, and
>> + * may be copied, distributed, and modified under those terms.
>> + */
>> +
>> +#ifndef _DT_BINDINGS_CLK_NPCM7XX_H
>> +#define _DT_BINDINGS_CLK_NPCM7XX_H
>> +
>> +#define NPCM7XX_CLK_PLL0 0
>> +#define NPCM7XX_CLK_PLL1 1
>> +#define NPCM7XX_CLK_PLL2 2
>> +#define NPCM7XX_CLK_GFX 3
>> +#define NPCM7XX_CLK_APB1 4
>> +#define NPCM7XX_CLK_APB2 5
>> +#define NPCM7XX_CLK_APB3 6
>> +#define NPCM7XX_CLK_APB4 7
>> +#define NPCM7XX_CLK_APB5 8
>> +#define NPCM7XX_CLK_MC 9
>> +#define NPCM7XX_CLK_CPU 10
>> +#define NPCM7XX_CLK_SPI0 11
>> +#define NPCM7XX_CLK_SPI3 12
>> +#define NPCM7XX_CLK_SPIX 13
>> +#define NPCM7XX_CLK_UART_CORE 14
>> +#define NPCM7XX_CLK_TIMER 15
>> +#define NPCM7XX_CLK_HOST_UART 16
>> +#define NPCM7XX_CLK_MMC 17
>> +#define NPCM7XX_CLK_SDHC 18
>> +#define NPCM7XX_CLK_ADC 19
>> +#define NPCM7XX_CLK_GFX_MEM 20
>> +#define NPCM7XX_CLK_USB_BRIDGE 21
>> +#define NPCM7XX_CLK_AXI 22
>> +#define NPCM7XX_CLK_AHB 23
>> +#define NPCM7XX_CLK_EMC 24
>> +#define NPCM7XX_CLK_GMAC 25
>> +
>> +#endif
>> --
>> 2.15.0.rc0.271.g36b669edcc-goog
>>