Re: [PATCH 10/10] arm64: dts: apple: Add minimal t8132 (M4) device trees

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [Medium] The `aic` node has a mismatched unit address and overlapping memory regions in its `reg` property.
- [Low] The `model` property for the MacBook Air (13-inch) erroneously declares the year as 2024 instead of 2025.
- [Low] `t8132` device trees are incorrectly placed at the very top of the `Makefile`, breaking the chronological sorting order.
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commit 281d92c4ca5eb8a2224c6bb0b9116c7518b422d1
Author: Yureka Lilian <yureka@cyberchaos.dev>

arm64: dts: apple: Add minimal t8132 (M4) device trees

This commit adds minimal device trees for a series of new Apple M4 devices,
including MacBook Pros, MacBook Airs, iMacs, and the Mac mini. The device
trees are limited to essential components like CPU cores, interrupts, and
serial, allowing a basic boot. It also notes that SMP support currently
remains unreliable.

> diff --git a/arch/arm64/boot/dts/apple/Makefile b/arch/arm64/boot/dts/apple/Makefile
> index 6fc3349a58428..181bd0e289653 100644
> --- a/arch/arm64/boot/dts/apple/Makefile
> +++ b/arch/arm64/boot/dts/apple/Makefile
> @@ -1,4 +1,10 @@
>  # SPDX-License-Identifier: GPL-2.0
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j604.dtb
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j623.dtb
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j624.dtb
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j713.dtb
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j715.dtb
> +dtb-$(CONFIG_ARCH_APPLE) += t8132-j773g.dtb
>  dtb-$(CONFIG_ARCH_APPLE) += s5l8960x-j71.dtb

[Severity: Low]
This isn't a bug, but should these new t8132 device trees be appended
to the bottom of the list rather than prepended at the top, to maintain
chronological sorting order in the Makefile?

[ ... ]

> diff --git a/arch/arm64/boot/dts/apple/t8132-j713.dts b/arch/arm64/boot/dts/apple/t8132-j713.dts
> index 0000000000000..b1f779c37d5fe
> --- /dev/null
> +++ b/arch/arm64/boot/dts/apple/t8132-j713.dts
[ ... ]
> +/ {
> +	compatible = "apple,j713", "apple,t8132", "apple,arm-platform";
> +	model = "Apple MacBook Air (13-inch, M4, 2024)";

[Severity: Low]
This isn't a bug, but does the model string contain a typo? The header
comment for this file identifies the target as a 2025 model, but the model
string exposes 2024 to userspace.

[ ... ]

> diff --git a/arch/arm64/boot/dts/apple/t8132.dtsi b/arch/arm64/boot/dts/apple/t8132.dtsi
> index 0000000000000..715980b5c7de4
> --- /dev/null
> +++ b/arch/arm64/boot/dts/apple/t8132.dtsi
[ ... ]
> +		aic: interrupt-controller@381180000 {
> +			compatible = "apple,t8132-aic3", "apple,t8122-aic3";
> +			#interrupt-cells = <3>;
> +			interrupt-controller;
> +			reg = <0x00000003 0x81000000 0x00000000 0x1cc000>,
> +			      <0x00000003 0x81040000 0x00000000 0x4000>;

[Severity: Medium]
Is the base address and memory region mapping for aic intentional?

The node defines a unit address of @381180000, but the reg property specifies
a base of 0x81000000 (translating to 0x381000000). Also, the first memory
region of size 0x1cc000 completely overlaps the second region starting at
0x81040000. 

Could this typo in the physical address map explain the unreliable smp boot
behavior mentioned in the commit message?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260705-apple-m4-initial-devicetrees-v1-0-e5655ee56523@cyberchaos.dev?part=10