Re: [PATCH 3/6] ARM: dts: Move BCM2711 RPi specific into separate dtsi

[Stefan Wahren <stefan.wahren@i2se.com>]

Hi Nicolas,

Am 01.06.21 um 12:03 schrieb nicolas saenz julienne:
> Hi Stefan,
> Thanks for having a go at this.
>
> On Sun, 2021-05-30 at 11:26 +0200, Stefan Wahren wrote:
>> There is a lot of Raspberry Pi specific stuff (neither SoC or board
>> specific) for the BCM2711 which is currently in the RPi 4 B dts. In order
>> to avoid copy & paste for every new BCM2711 based Raspberry Pi, move it
>> into a separate dtsi.
>>
>> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
>> ---
>>  arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 62 +----------------------------
>>  arch/arm/boot/dts/bcm2711-rpi.dtsi    | 75 +++++++++++++++++++++++++++++++++++
>>  2 files changed, 76 insertions(+), 61 deletions(-)
>>  create mode 100644 arch/arm/boot/dts/bcm2711-rpi.dtsi
>>
>> diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> index 3b4ab94..78142a0 100644
>> --- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> @@ -1,11 +1,9 @@
>>  // SPDX-License-Identifier: GPL-2.0
>>  /dts-v1/;
>>  #include "bcm2711.dtsi"
>> -#include "bcm2835-rpi.dtsi"
>> +#include "bcm2711-rpi.dtsi"
>>  #include "bcm283x-rpi-usb-peripheral.dtsi"
>>  
>>
>> -#include <dt-bindings/reset/raspberrypi,firmware-reset.h>
>> -
>>  / {
>>  	compatible = "raspberrypi,4-model-b", "brcm,bcm2711";
>>  	model = "Raspberry Pi 4 Model B";
>> @@ -22,10 +20,7 @@
>>  	};
>>  
>>
>>  	aliases {
>> -		emmc2bus = &emmc2bus;
>>  		ethernet0 = &genet;
> Why not picking this one? nor the relevant DT nodes? I belive it's available on
> all the bcm2711 based boards.
While i agree that most of the boards [1] support Ethernet, the PHY
stuff is almost board specific.
>
>> -		pcie0 = &pcie0;
>> -		blconfig = &blconfig;
>>  	};
>>  
>>
>>  	leds {
>> @@ -80,11 +75,6 @@
>>  };
>>  
>>
>>  &firmware {
>> -	firmware_clocks: clocks {
>> -		compatible = "raspberrypi,firmware-clocks";
>> -		#clock-cells = <1>;
>> -	};
>> -
>>  	expgpio: gpio {
> Why not taking this one too and letting each dts file define its own
> 'gpio-line-names'?
Agree
>
>>  		compatible = "raspberrypi,firmware-gpio";
>>  		gpio-controller;
>> @@ -99,11 +89,6 @@
>>  				  "";
>>  		status = "okay";
>>  	};
>> -
>> -	reset: reset {
>> -		compatible = "raspberrypi,firmware-reset";
>> -		#reset-cells = <1>;
>> -	};
>>  };
>>  
>>
>>  &gpio {
>> @@ -180,23 +165,13 @@
>>  };
>>  
>>
>>  &hdmi0 {
>> -	clocks = <&firmware_clocks 13>, <&firmware_clocks 14>, <&dvp 0>, <&clk_27MHz>;
>> -	clock-names = "hdmi", "bvb", "audio", "cec";
>> -	wifi-2.4ghz-coexistence;
>>  	status = "okay";
>>  };
>>  
>>
>>  &hdmi1 {
>> -	clocks = <&firmware_clocks 13>, <&firmware_clocks 14>, <&dvp 1>, <&clk_27MHz>;
>> -	clock-names = "hdmi", "bvb", "audio", "cec";
>> -	wifi-2.4ghz-coexistence;
>>  	status = "okay";
>>  };
>>  
>>
>> -&hvs {
>> -	clocks = <&firmware_clocks 4>;
>> -};
>> -
>>  &pixelvalve0 {
>>  	status = "okay";
>>  };
>> @@ -219,22 +194,6 @@
>>  	status = "okay";
>>  };
>>  
>>
>> -&rmem {
>> -	/*
>> -	 * RPi4's co-processor will copy the board's bootloader configuration
>> -	 * into memory for the OS to consume. It'll also update this node with
>> -	 * its placement information.
>> -	 */
>> -	blconfig: nvram@0 {
>> -		compatible = "raspberrypi,bootloader-config", "nvmem-rmem";
>> -		#address-cells = <1>;
>> -		#size-cells = <1>;
>> -		reg = <0x0 0x0 0x0>;
>> -		no-map;
>> -		status = "disabled";
>> -	};
>> -};
>> -
>>  /* SDHCI is used to control the SDIO for wireless */
>>  &sdhci {
>>  	#address-cells = <1>;
>> @@ -273,21 +232,6 @@
>>  	};
>>  };
>>  
>>
>> -&pcie0 {
>> -	pci@1,0 {
>> -		#address-cells = <3>;
>> -		#size-cells = <2>;
>> -		ranges;
>> -
>> -		reg = <0 0 0 0 0>;
>> -
>> -		usb@1,0 {
>> -			reg = <0x10000 0 0 0 0>;
>> -			resets = <&reset RASPBERRYPI_FIRMWARE_RESET_ID_USB>;
>> -		};
>> -	};
>> -};
>> -
> This is not relevant to CM4, maybe we should leave it in the .dts
Okay
>
>>  /* uart0 communicates with the BT module */
>>  &uart0 {
> What about 'uart1'? I belive the configuration is the same for all boards. pwm1
> also comes to mind.

I wouldn't include pinmux dependent stuff here, because this is very
specific to the board and use case [1].

But there is a trick for the Pi 400, which is very similiar to the Pi 4
B. We could include the pi4.dts in the pi400.dts. Additional i would
keep this patch for CM4 and co.

Regards
Stefan

[1] -
https://afterhourscoding.wordpress.com/2021/02/21/a-list-of-raspberry-pi-compute-module-carrier-boards-and-devices/

>
> Regards,
> Nicolas
>
>