Re: [PATCH v2 2/2] riscv: dts: spacemit: Add cpu scaling for K1 SoC

[Anand Moon]

Hi Aurelien,

Thanks for looking into this.

On Tue, 21 Apr 2026 at 02:46, Aurelien Jarno <aurelien@xxxxxxxxxxx> wrote:
>
> Hi Anand,
>
> On 2026-04-16 17:07, Anand Moon wrote:
> > After reviewing the Banana Pi F3 schematics, I confirmed that Buck1 and Buck2
> > Both supply the CORE_0V9 with 0.9V±1% rail. To resolve the restriction errors,
> > I expanded the voltage range in the DTS to 500,000–950,000 µV.
> >
> > Additionally, I updated the DTS to map the second CPU cluster (cores 4–7)
> > to Buck2 to better align with the hardware's power distribution.
>
> Actually the output of Buck1 and Buck2 are connected together, so they
> should always be configured with the same output voltage. And both
> clusters should be mapped to both outputs.
>
You should review the regulator_summary below, as it may indicate
it could be Big.Little architecture cluster.

$ cat /sys/kernel/debug/regulator/regulator_summary
 regulator                      use open bypass  opmode voltage
current     min     max
---------------------------------------------------------------------------------------
 regulator-dummy                  1    0      0 unknown     0mV
0mA     0mV     0mV
 dc_in_12v                        2    1      0 unknown 12000mV
0mA 12000mV 12000mV
    vcc_4v                        8   10      0 unknown  4000mV
0mA  4000mV  4000mV
       buck1                      2    1      0 unknown   950mV
0mA   500mV   950mV
          cpu0-cpu                1
0mA   950mV   950mV
       buck2                      2    1      0 unknown   950mV
0mA   500mV   950mV
          cpu4-cpu                1
0mA   950mV   950mV

> I also wonder why in the original patch the buck1 regulator is named
> buck1_3v45, from the schematics, it should rather be called buck1_0v9.
>
Yep, you are correct., It should be called buck1_0v9.

> Regards
> Aurelien
>
> --
> Aurelien Jarno                          GPG: 4096R/1DDD8C9B
> aurelien@xxxxxxxxxxx                     http://aurel32.net

Thanks
-Anand