Re: [PATCH 2/2] arm64: tegra: Add Lenovo ThinkEdge SE70 carrier board DTS

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 5 potential issue(s) to consider:
- [High] Missing `no-1-8-v` property or 1.8V-capable `vqmmc-supply` for `mmc@3440000` while UHS modes are enabled in the base DTSI.
- [High] Missing `bus-width` property for the SD card slot (`mmc@3440000`).
- [Medium] Device tree schema violation for 'fixed-regulators' wrapper and its child node.
- [Medium] The patch fails to disable the unused SPI peripheral as claimed in the commit message.
- [Medium] Missing `disable-wp` property in the SD card node (`mmc@3440000`).
--

commit d7f4007a1b474f4e8527dff37fcaa0da82f91d42
Author: Jiqi Li <lijq9@lenovo.com>

arm64: tegra: Add Lenovo ThinkEdge SE70 carrier board DTS

ThinkEdge SE70 is a fanless industrial edge gateway built around
NVIDIA Tegra194 Xavier NX SOM. This patch adds a standalone device
tree file describing core carrier board peripherals.

> No fan, PWM, tachometer, extra camera/spi peripherals are present
> on this passively cooled platform, so unused nodes are explicitly
> disabled following mainline device tree best practices.

[Severity: Medium]
Does this patch actually disable the extra SPI peripherals as claimed?

The tegra194-p3509-0000.dtsi explicitly enables the spi@3270000 node, but
there doesn't appear to be an override to disable it in this file. The
unpopulated SPI flash driver will probe on boot and waste resources.

> diff --git a/arch/arm64/boot/dts/nvidia/tegra194-lenovo-thinkedge-se70.dts b/arch/arm64/boot/dts/nvidia/tegra194-lenovo-thinkedge-se70.dts
> new file mode 100644
> index 0000000000000..44a7ae9a05bfb
> --- /dev/null
> +++ b/arch/arm64/boot/dts/nvidia/tegra194-lenovo-thinkedge-se70.dts

[ ... ]

> @@ -14,6 +14,6 @@
> +	/* Fixed 3.3V regulator for external SD card slot */
> +	fixed-regulators {
> +		compatible = "simple-bus";
> +		ap2306gn_3v3_sd: ap2306gn-3v3-sd {
> +			compatible = "regulator-fixed";
> +			regulator-name = "ap2306gn-3v3-sd";

[Severity: Medium]
Does this fixed-regulators node comply with the device tree schemas?

Using simple-bus requires the #address-cells, #size-cells, and ranges
properties, which are missing here. Additionally, the ap2306gn-3v3-sd child
node does not start with the regulator- prefix as required by the
fixed-regulator.yaml schema.

This seems to contradict the commit message claim that dt_binding_check
passed without errors.

[ ... ]

> @@ -95,6 +95,6 @@
> +		/* SDMMC3 for external user SD card slot with dedicated 3.3V power */
> +		mmc@3440000 {
> +			vmmc-supply = <&ap2306gn_3v3_sd>;
> +			cd-gpios = <&gpio_aon TEGRA194_AON_GPIO(CC, 4) GPIO_ACTIVE_HIGH>;
> +			status = "okay";
> +		};

[Severity: High]
Does this configuration need a no-1-8-v property or a 1.8V-capable
vqmmc-supply?

The tegra194.dtsi enables UHS-I modes for mmc@3440000, which require 1.8V
signaling. Since this node only defines a fixed 3.3V supply without disabling
1.8V modes, won't the MMC core try to switch the SoC pads to 1.8V signaling
while the card is powered at 3.3V? This could cause I/O failures and
hardware overstress.

[Severity: High]
Should this node specify a bus-width property?

If the bus-width property is omitted, the MMC subsystem defaults to 1-bit
mode. Since the parent sdmmc3 node in tegra194.dtsi does not specify a
bus-width, will this SD card operate in a degraded 1-bit mode, artificially
crippling read and write performance?

[Severity: Medium]
Could this node be missing a disable-wp property?

If the board leaves the internal WP pin floating and disable-wp is absent,
could the kernel randomly mount the SD card as read-only?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260626091349.570091-1-lijq9@lenovo.com?part=2