On 17/03/2023 10:52, Jacky Huang wrote: > Dear Krzysztof, > > Thanks for your advice. > > On 2023/3/17 下午 05:13, Krzysztof Kozlowski wrote: >> On 17/03/2023 04:47, Jacky Huang wrote: >>>>> + >>>>> + nuvoton,pll-mode: >>>>> + description: >>>>> + A list of PLL operation mode corresponding to CAPLL, DDRPLL, APLL, >>>>> + EPLL, and VPLL in sequential. The operation mode value 0 is for >>>>> + integer mode, 1 is for fractional mode, and 2 is for spread >>>>> + spectrum mode. >>>>> + $ref: /schemas/types.yaml#/definitions/uint32-array >>>>> + maxItems: 5 >>>>> + items: >>>>> + minimum: 0 >>>>> + maximum: 2 >>>> Why exactly this is suitable for DT? >>> I will use strings instead. >> I have doubts why PLL mode is a property of DT. Is this a board-specific >> property? > > CA-PLL has mode 0 only. > DDRPLL, APLL, EPLL, and VPLL have the same PLL design that supports > integer mode, fractional mode, and spread spctrum mode. The PLL mode > is controlled by clock controller register. I think it's not board-specific. You described the feature but that does not answer why this is suitable in DT. If this is not board-specific, then it is implied by compatible, right? Or it does not have to be in DT at all. Best regards, Krzysztof