Re: [PATCH 3/5] riscv: dts: spacemit: k3-com260: Add SPI NOR flash

["Troy Mitchell" <troy.mitchell@linux.spacemit.com>]

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Hi Sarah,

On Fri, 6 Nov 2026 17:25:48 +0100, Sarah Emery wrote:
> > +			uboot@210000 {
> > +				reg = <0x210000 0x5f0000>;
> > +			};
>
> This partition ends at 0x800000. On the CoM260 with EDK2, 0x700000 to
> 0x7c0000 holds the variable store (NVRAM and FTW), so reflashing this
> partition from Linux would erase it.
>
> I think we could split it like this:
>
>     uboot@210000 {
>        reg = <0x210000 0x4f0000>;
>     };
>
>     var@700000 {
>        reg = <0x700000 0xc0000>;
>        read-only;
>     };
>
> What do you think?

The layout here is the one used by the SpacemiT boot firmware for K3,
where U-Boot owns everything from 0x210000 to the end of the flash.
The EDK2 that SpacemiT ships for K3 (including the CoM260
configurations) keeps its variables in memory and does not use the
flash for them, so it has nothing at 0x700000.

Which EDK2 build places the variable store at 0x700000?

> The Pico-ITX node also uses 0x5f0000, but I think it should be modified
> to split out the var part too if it makes sense here.

Same answer as above.

> The Pico-ITX flash node also has vcc-supply = <&aldo2>.
> Shouldn't this be present here as well?
Yes. On the CoM260 the flash is also powered from P1V8_QSPI, which
comes from ALDO2. I'll add it in v2.

Thanks for the review.

-- 
Troy Mitchell

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