Hi Andrew,

On Mon, 27 Oct 2025 at 13:01, Andrew Lunn [off-list ref] wrote:

On Mon, Oct 27, 2025 at 02:42:01AM +0000, Ryan Chen wrote:

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Subject: Re: [PATCH v6 4/6] arm64: dts: aspeed: Add initial AST2700 SoC device
tree

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SoC0, referred to as the CPU die, contains a dual-core Cortex-A35
cluster and two Cortex-M4 cores, along with its own clock/reset
domains and high-speed peripheral set.

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SoC1, referred to as the I/O die, contains the Boot MCU and its own
clock/reset domains and low-speed peripheral set, and is responsible
for system boot and control functions.

So is the same .dtsi file shared by both systems?

This .dtsi represents the Cortex-A35 view only and is not shared
with the Cortex-M4 or the Boot MCU side, since they are separate
32-bit and 64-bit systems running independent firmware.

DT describes the hardware. The .dtsi file could be shared, you just
need different status = <>; lines in the dtb blob.

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How do you partition devices
so each CPU cluster knows it has exclusive access to which peripherals?

Before the system is fully brought up, Boot MCU configure hardware
controllers handle the resource partitioning to ensure exclusive access.

Are you saying it modifies the .dtb blob and changes some status =
"okay"; to "disabled";?

"reserved" is the appropriate status value for that.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds