On Thu, Feb 13, 2025 at 02:29:41PM +0100, Geert Uytterhoeven wrote: >Hi Peng, > >On Thu, 13 Feb 2025 at 13:35, Peng Fan <peng.fan@xxxxxxxxxxx> wrote: >> On Thu, Feb 13, 2025 at 11:16:31AM +0100, Geert Uytterhoeven wrote: >> >On Fri, 24 Jan 2025 at 15:42, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote: >> >> Just FYI, below is a foward of pull request for dtschema for bindings >> >> adding spread spectrum to clocks. As Clock framework maintainers this >> >> might be relevant to you. >> >> >> >> -------- Forwarded Message -------- >> >> Subject: [devicetree-org/dt-schema] schemas: introduce >> >> assigned-clock-sscs (PR #154) >> >> Date: Fri, 24 Jan 2025 04:31:30 -0800 >> >> From: Peng Fan <notifications@xxxxxxxxxx> >> >> Reply-To: devicetree-org/dt-schema >> >> <reply+ACPRLI5YLXX27TFZX2P7NVOFT5USFEVBNHHKO4ZXHM@xxxxxxxxxxxxxxxx> >> >> To: devicetree-org/dt-schema <dt-schema@xxxxxxxxxxxxxxxxxx> >> >> CC: Subscribed <subscribed@xxxxxxxxxxxxxxxxxx> >> >> >> >> To support spread spectrum clock, introduce assigned-clock-sscs, it is >> >> an uint32-matrix with format multiple elements of below >> >> <modfreq spreadpercentage modmethod>, <...> >> >> You can view, comment on, or merge this pull request online at: >> >> >> >> https://github.com/devicetree-org/dt-schema/pull/154 >> >> >> >> -- Commit Summary -- >> >> >> >> * schemas: introduce assigned-clock-sscs >> > >> >> assigned-clock-sscs: >> >> $ref: /schemas/types.yaml#/definitions/uint32-matrix >> >> items: >> >> items: >> >> - description: The modulation frequency >> >> - description: The modulation depth in permyriad >> >> - description: The modulation method, down(2), up(1), center(0) >> > >> >Is there a way to explicitly disable it, if it was enabled by the >> >firmware? See also my comment in "Re: [PATCH v2 1/4] clk: Introduce >> >> The binding here is just to describe the parameter to configure >> spread spectrum of a clk. >> >> To disable spread spectrum, the clk_hw_set_spread_spectrum could be >> used with enable as false or as you suggested using CLK_SSC_NONE_SPREAD? > >But the bindings don't have an enable flag... The modulation method maybe updated to down(3), up(2), center(1), no modulation(0). Then no need a separate entry for enable. Thanks, Peng. > >> >clk_hw_set_spread_spectrum". >> > >> >> minimum: 0 >> >> maximum: 2 >> > >> >What's the meaning of these limits? >> >> Modulation has three methods: >> Down-spread modulation >> Up-spread modulation >> Center-spread modulation. >> >> I use 2 for down, 1 for up, 0 for center here. So the limits: >> min: 0, max: 2. > >Silly me, they apply to the last description... > >Gr{oetje,eeting}s, > > Geert > >-- >Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx > >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 >
