Re: [PATCH v1 2/3] arm64: dts: ti: Add support for Variscite VAR-SOM-AM62P

[Krzysztof Kozlowski <krzk@kernel.org>]

On 08/07/2025 20:48, Stefano Radaelli wrote:
> Add device tree support for the Variscite VAR-SOM-AM62P system on module.
> This SOM is designed to be used with various carrier boards.
> 
> The module includes:
> - AM62Px Sitara MPU processor
> - Up to 8GB of DDR4-3733 memory
> - eMMC storage memory
> - PS6522430 chip as a Power Management Integrated circuit (PMIC)
> - Integrated 10/100/1000 Mbps Ethernet Transceiver Analog Devices ADIN1300
> - Resistive touch panel interface controller TI TSC2046
> - I2C interfaces
> 
> Only SOM-specific peripherals are enabled by default. Carrier board
> specific interfaces are left disabled to be enabled in the respective
> carrier board device trees.
> 
> Link: https://www.variscite.it/product/system-on-module-som/cortex-a53-krait/var-som-am62p-ti-sitara-am62px/
> 
> Signed-off-by: Stefano Radaelli <stefano.radaelli21@gmail.com>
> ---
>  arch/arm64/boot/dts/ti/k3-am62p5-var-som.dtsi | 379 ++++++++++++++++++
>  1 file changed, 379 insertions(+)
>  create mode 100644 arch/arm64/boot/dts/ti/k3-am62p5-var-som.dtsi
> 
> diff --git a/arch/arm64/boot/dts/ti/k3-am62p5-var-som.dtsi b/arch/arm64/boot/dts/ti/k3-am62p5-var-som.dtsi
> new file mode 100644
> index 000000000000..1d4ebc484d55
> --- /dev/null
> +++ b/arch/arm64/boot/dts/ti/k3-am62p5-var-som.dtsi
> @@ -0,0 +1,379 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Common dtsi for Variscite VAR-SOM-AM62P
> + *
> + * Copyright (C) 2021-2022 Texas Instruments Incorporated - https://www.ti.com/
> + * Copyright (C) 2025 Variscite Ltd. - https://www.variscite.com/
> + *
> + */
> +
> +/dts-v1/;
> +
> +#include <dt-bindings/gpio/gpio.h>
> +#include <dt-bindings/input/input.h>
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +#include <dt-bindings/leds/common.h>
> +#include <dt-bindings/pwm/pwm.h>
> +#include "k3-am62p5.dtsi"
> +
> +/ {
> +	compatible = "variscite,am62p-var-som", "ti,am62p5";
> +
> +	iw612_pwrseq: iw612_pwrseq {

Follow DTS coding style. This applies to multiple places.

Also:
Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation


> +		compatible = "mmc-pwrseq-simple";
> +		post-power-on-delay-ms = <100>;
> +		power-off-delay-us = <10000>;
> +		reset-gpios = <&main_gpio0 54 GPIO_ACTIVE_LOW>,	/* WIFI_PWR_EN */
> +			      <&main_gpio0 59 GPIO_ACTIVE_LOW>;	/* WIFI_EN */
> +		status = "okay";

Why? Drop.

> +	};
> +
> +	emmc_pwrseq: pwrseq@0 {

It does not look like you tested the DTS against bindings. Please run
`make dtbs_check W=1` (see
Documentation/devicetree/bindings/writing-schema.rst or
https://www.linaro.org/blog/tips-and-tricks-for-validating-devicetree-sources-with-the-devicetree-schema/
for instructions).
Maybe you need to update your dtschema and yamllint. Don't rely on
distro packages for dtschema and be sure you are using the latest
released dtschema.

> +		compatible = "mmc-pwrseq-emmc";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&emmc_pwrseq_pins>;
> +		reset-gpios = <&main_gpio0 49 GPIO_ACTIVE_LOW>;
> +	};
> +
> +	memory@80000000 {
> +		/* 8G RAM */
> +		reg = <0x00000000 0x80000000 0x00000000 0x80000000>,
> +		      <0x00000008 0x80000000 0x00000001 0x80000000>;
> +		device_type = "memory";
> +		bootph-pre-ram;
> +	};
> +
> +	opp-table {
> +		/* Add 1.4GHz OPP for am62p5-sk board. Requires VDD_CORE at 0v85 */
> +		opp-1400000000 {
> +			opp-hz = /bits/ 64 <1400000000>;
> +			opp-supported-hw = <0x01 0x0004>;
> +			clock-latency-ns = <6000000>;
> +		};
> +	};
> +
> +	reserved_memory: reserved-memory {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +		ranges;
> +
> +		rtos_ipc_memory_region: rtos-ipc-memory@9b500000 {
> +			compatible = "shared-dma-pool";
> +			reg = <0x00 0x9b500000 0x00 0x00300000>;
> +			no-map;
> +		};
> +
> +		mcu_r5fss0_core0_dma_memory_region: mcu-r5fss-dma-memory-region@9b800000 {
> +			compatible = "shared-dma-pool";
> +			reg = <0x00 0x9b800000 0x00 0x00100000>;
> +			no-map;
> +		};
> +
> +		mcu_r5fss0_core0_memory_region: mcu-r5fss-memory-region@9b900000 {
> +			compatible = "shared-dma-pool";
> +			reg = <0x00 0x9b900000 0x00 0x00f00000>;
> +			no-map;
> +		};
> +
> +		wkup_r5fss0_core0_dma_memory_region: r5f-dma-memory@9c800000 {
> +			compatible = "shared-dma-pool";
> +			reg = <0x00 0x9c800000 0x00 0x00100000>;
> +			no-map;
> +		};
> +
> +		wkup_r5fss0_core0_memory_region: r5f-memory@9c900000 {
> +			compatible = "shared-dma-pool";
> +			reg = <0x00 0x9c900000 0x00 0x01e00000>;
> +			no-map;
> +		};
> +
> +		secure_tfa_ddr: tfa@9e780000 {
> +			reg = <0x00 0x9e780000 0x00 0x80000>;
> +			no-map;
> +		};
> +
> +		secure_ddr: optee@9e800000 {
> +			reg = <0x00 0x9e800000 0x00 0x01800000>; /* for OP-TEE */
> +			no-map;
> +		};
> +	};
> +
> +	vcc_3v3: vcc-3v3 {

Please use name for all fixed regulators which matches current format
recommendation: 'regulator-[0-9]v[0-9]'

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/regulator/fixed-regulator.yaml?h=v6.11-rc1#n46


Best regards,
Krzysztof