Re: [PATCH 1/1] arm64: dts: rockchip: enable NPU on Radxa E52C

["Diederik de Haas" <diederik@cknow-tech.com>]

On Tue Aug 11, 2026 at 6:39 AM CEST, Jimmy Hon wrote:
> On Mon, Aug 10, 2026 at 6:20 AM Chukun Pan <amadeus@jmu.edu.cn> wrote:
>>
>> Like the RK3588, the RK3582 has NPUs. Enable the NPU cores and their
>> MMUs, and connect the regulators.
>>
>> Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
>> ---
>>  .../boot/dts/rockchip/rk3582-radxa-e52c.dts   | 34 +++++++++++++++++++
>>  1 file changed, 34 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/rockchip/rk3582-radxa-e52c.dts b/arch/arm64/boot/dts/rockchip/rk3582-radxa-e52c.dts
>> index 854c118418eb..dd29a3ea7031 100644
>> --- a/arch/arm64/boot/dts/rockchip/rk3582-radxa-e52c.dts
>> +++ b/arch/arm64/boot/dts/rockchip/rk3582-radxa-e52c.dts
>> @@ -300,6 +300,10 @@ &pcie2x1l2 {
>>         status = "okay";
>>  };
>>
>> +&pd_npu {
>> +       domain-supply = <&vdd_npu_s0>;
>> +};
> Now that the power domain has control of the regulator. The regulator
> should have regulator-always-on removed, so it can be powered down.

Next to that, quoting a question that was raised earlier here:
https://lore.kernel.org/all/b9a5beb6-b701-430c-b667-44780736dd89@kwiboo.xyz/

"Why is boot-on kept?, NPU is likely not needed until OS has started.

With PD domain-supply the regulator should be enabled automatically, or
is there some other issue that requires boot firmware to enable this
regulator before OS is started?"

I do realize quite a few other boards have it too, but maybe they
shouldn't have it/them either?

Cheers,
  Diederik