Hi Geert, On Thu, Feb 13, 2025 at 11:16:31AM +0100, Geert Uytterhoeven wrote: >CC devicetree > >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? >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. Thanks, Peng > >[1] https://lore.kernel.org/CAMuHMdWn+sKiC1B4MF1vHwS2ArFYQXGzpYi2EcsyERPSCc9bvQ@xxxxxxxxxxxxxx > >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 >
