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SubjectRe: [RESEND PATCH v7 5/5] clk: ti: add am33xx/am43xx spread spectrum clock support
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Quoting Dario Binacchi (2021-06-06 13:22:53)
> The patch enables spread spectrum clocking (SSC) for MPU and LCD PLLs.
> As reported by the TI spruh73x/spruhl7x RM, SSC is only supported for
> the DISP/LCD and MPU PLLs on am33xx/am43xx. SSC is not supported for
> DDR, PER, and CORE PLLs.
>
> Calculating the required values and setting the registers accordingly
> was taken from the set_mpu_spreadspectrum routine contained in the
> arch/arm/mach-omap2/am33xx/clock_am33xx.c file of the u-boot project.
>
> In locked condition, DPLL output clock = CLKINP *[M/N]. In case of
> SSC enabled, the reference manual explains that there is a restriction
> of range of M values. Since the omap2_dpll_round_rate routine attempts
> to select the minimum possible N, the value of M obtained is not
> guaranteed to be within the range required. With the new "ti,min-div"
> parameter it is possible to increase N and consequently M to satisfy the
> constraint imposed by SSC.
>
> Signed-off-by: Dario Binacchi <dariobin@libero.it>
> Reviewed-by: Tero Kristo <kristo@kernel.org>
>
> ---

Applied to clk-next

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