Hi Krzysztof Kozlowski, > Subject: Re: [PATCH RFC 1/3] dt-bindings: clock: Add Renesas versa3 clock > generator bindings > > On 09/03/2023 10:53, Biju Das wrote: > > > > > >> -----Original Message----- > >> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > >> Sent: Thursday, March 9, 2023 9:44 AM > >> To: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>; Michael Turquette > >> <mturquette@xxxxxxxxxxxx>; Stephen Boyd <sboyd@xxxxxxxxxx>; Rob > >> Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski > >> <krzysztof.kozlowski+dt@xxxxxxxxxx> > >> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; linux-renesas- > >> soc@xxxxxxxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx; > >> devicetree@xxxxxxxxxxxxxxx; Fabrizio Castro > >> <fabrizio.castro.jz@xxxxxxxxxxx> > >> Subject: Re: [PATCH RFC 1/3] dt-bindings: clock: Add Renesas versa3 > >> clock generator bindings > >> > >> On 09/03/2023 10:18, Biju Das wrote: > >>> > >>> > >>>> -----Original Message----- > >>>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > >>>> Sent: Thursday, March 9, 2023 9:14 AM > >>>> To: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>; Michael Turquette > >>>> <mturquette@xxxxxxxxxxxx>; Stephen Boyd <sboyd@xxxxxxxxxx>; Rob > >>>> Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski > >>>> <krzysztof.kozlowski+dt@xxxxxxxxxx> > >>>> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; linux-renesas- > >>>> soc@xxxxxxxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx; > >>>> devicetree@xxxxxxxxxxxxxxx; Fabrizio Castro > >>>> <fabrizio.castro.jz@xxxxxxxxxxx> > >>>> Subject: Re: [PATCH RFC 1/3] dt-bindings: clock: Add Renesas versa3 > >>>> clock generator bindings > >>>> > >>>> On 09/03/2023 08:57, Biju Das wrote: > >>>>>>> It is clk generator HW specific. Clk generator is vital > >>>>>>> component which provides clocks to the system. > >>>>>> > >>>>>> Every clock controller is vital... > >>>>>> > >>>>>>> We are providing some hardware feature which is exposed as dt > >>>>>>> properties. > >>>>>>> > >>>>>>> Like clock output is fixed rate clock or dynamic rate clock/ > >>>>>> > >>>>>> OK, I wait then for proper description which will explain and > >>>>>> justify > >>>> this. > >>>>> > >>>>> Here it is, Please let me know is it ok? > >>>>> > >>>>> renesas,output-clock-fixed-rate-mode: > >>>>> type: boolean > >>>>> description: > >>>>> In output clock fixed rate mode, the output clock frequency > >>>>> is > >>>> always > >>>>> fixed and the hardware will use the values from the OTP or > >>>>> full > >>>> register > >>>>> map initialized during boot. > >>>>> If not given, the output clock rate is not fixed. > >>>>> maxItems: 6 > >>>> > >>>> boolean is scalar, not array, so no maxItems. If the frequency is > >>>> taken from OTP or register map, why they cannot also provide > >>>> information the clock is fixed? > >>> > >>> OK, I will make an array property instead. From HW perspective each > >>> clock output from the Clock generator is controllable ie, fixed rate > >>> or > >> dynamic rate. > >>> > >>> If all the output clocks are fixed rate one, then frequency is taken > >>> from OTP or register map. But if any one clock output generates > >>> dynamic rate, then it uses dynamic settings. > >> > >> Second try, same question, let me know if it is not clear: > >> > >> "why they cannot also provide information the clock is fixed?" > > > > This information we are providing through dt. > > No, you are not. We just discuss it. If we do not agree, you are not going > to provide information through DT. > > > > > It is a complex clock generator which provides 6 HW clock outputs. > > The 6 HW clock outputs can be individually controllable to generate > > Either fixed frequency or dynamic frequency. > > Ah, indeed. 6 clock outputs prohibits configuring this from OTP. If only > there were 5 outputs then it would be possible... > > > > > Output clk1 "diff2", > > Output clk2 "diff1", > > Output clk3 "se3", > > Output clk4 "se2", > > Output clk5 "se1", > > Output clk6 "ref" > > > > I want to make "Output clk4" from clock generator as dynamic frequency > > one And make other clock frequency from clock generator as fixed one. > > > > How do you describe this in dt? Please share your thoughts. > > Read from OTP or registers. Looks no other option. So will drop this property and match the one from OTP with full regmap. Cheers, Biju
