Re: [PATCH v2 4/8] clk: imx: pll14xx: consolidate rate calculation

[Abel Vesa <abel.vesa@nxp.com>]

On 22-02-25 09:29:33, Sascha Hauer wrote:
> The PLL driver has support for two different PLLs: The pll1416x and
> the pll1443x. The latter has support for an additional kdiv value.
> recalc_rate can be the same calculation when kdiv is assumed to be zero
> for the PLL which doesn't support that value.
> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Reviewed-by: Abel Vesa <abel.vesa@nxp.com>

> ---
>  drivers/clk/imx/clk-pll14xx.c | 59 +++++++++++++++--------------------
>  1 file changed, 26 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/clk/imx/clk-pll14xx.c b/drivers/clk/imx/clk-pll14xx.c
> index fabb380b87305..ebd5d888fea6d 100644
> --- a/drivers/clk/imx/clk-pll14xx.c
> +++ b/drivers/clk/imx/clk-pll14xx.c
> @@ -97,6 +97,20 @@ static const struct imx_pll14xx_rate_table *imx_get_pll_settings(
>  	return NULL;
>  }
>  
> +static long pll14xx_calc_rate(struct clk_pll14xx *pll, int mdiv, int pdiv,
> +			      int sdiv, int kdiv, unsigned long prate)
> +{
> +	u64 fvco = prate;
> +
> +	/* fvco = (m * 65536 + k) * Fin / (p * 65536) */
> +	fvco *= (mdiv * 65536 + kdiv);
> +	pdiv *= 65536;
> +
> +	do_div(fvco, pdiv << sdiv);
> +
> +	return fvco;
> +}
> +
>  static long clk_pll14xx_round_rate(struct clk_hw *hw, unsigned long rate,
>  			unsigned long *prate)
>  {
> @@ -113,46 +127,25 @@ static long clk_pll14xx_round_rate(struct clk_hw *hw, unsigned long rate,
>  	return rate_table[i - 1].rate;
>  }
>  
> -static unsigned long clk_pll1416x_recalc_rate(struct clk_hw *hw,
> -						  unsigned long parent_rate)
> -{
> -	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
> -	u32 mdiv, pdiv, sdiv, pll_div;
> -	u64 fvco = parent_rate;
> -
> -	pll_div = readl_relaxed(pll->base + DIV_CTL0);
> -	mdiv = FIELD_GET(MDIV_MASK, pll_div);
> -	pdiv = FIELD_GET(PDIV_MASK, pll_div);
> -	sdiv = FIELD_GET(SDIV_MASK, pll_div);
> -
> -	fvco *= mdiv;
> -	do_div(fvco, pdiv << sdiv);
> -
> -	return fvco;
> -}
> -
> -static unsigned long clk_pll1443x_recalc_rate(struct clk_hw *hw,
> +static unsigned long clk_pll14xx_recalc_rate(struct clk_hw *hw,
>  						  unsigned long parent_rate)
>  {
>  	struct clk_pll14xx *pll = to_clk_pll14xx(hw);
> -	u32 mdiv, pdiv, sdiv, pll_div_ctl0, pll_div_ctl1;
> -	short int kdiv;
> -	u64 fvco = parent_rate;
> +	u32 mdiv, pdiv, sdiv, kdiv, pll_div_ctl0, pll_div_ctl1;
>  
>  	pll_div_ctl0 = readl_relaxed(pll->base + DIV_CTL0);
> -	pll_div_ctl1 = readl_relaxed(pll->base + DIV_CTL1);
>  	mdiv = FIELD_GET(MDIV_MASK, pll_div_ctl0);
>  	pdiv = FIELD_GET(PDIV_MASK, pll_div_ctl0);
>  	sdiv = FIELD_GET(SDIV_MASK, pll_div_ctl0);
> -	kdiv = FIELD_GET(KDIV_MASK, pll_div_ctl1);
>  
> -	/* fvco = (m * 65536 + k) * Fin / (p * 65536) */
> -	fvco *= (mdiv * 65536 + kdiv);
> -	pdiv *= 65536;
> -
> -	do_div(fvco, pdiv << sdiv);
> +	if (pll->type == PLL_1443X) {
> +		pll_div_ctl1 = readl_relaxed(pll->base + DIV_CTL1);
> +		kdiv = FIELD_GET(KDIV_MASK, pll_div_ctl1);
> +	} else {
> +		kdiv = 0;
> +	}
>  
> -	return fvco;
> +	return pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, kdiv, parent_rate);
>  }
>  
>  static inline bool clk_pll14xx_mp_change(const struct imx_pll14xx_rate_table *rate,
> @@ -363,20 +356,20 @@ static const struct clk_ops clk_pll1416x_ops = {
>  	.prepare	= clk_pll14xx_prepare,
>  	.unprepare	= clk_pll14xx_unprepare,
>  	.is_prepared	= clk_pll14xx_is_prepared,
> -	.recalc_rate	= clk_pll1416x_recalc_rate,
> +	.recalc_rate	= clk_pll14xx_recalc_rate,
>  	.round_rate	= clk_pll14xx_round_rate,
>  	.set_rate	= clk_pll1416x_set_rate,
>  };
>  
>  static const struct clk_ops clk_pll1416x_min_ops = {
> -	.recalc_rate	= clk_pll1416x_recalc_rate,
> +	.recalc_rate	= clk_pll14xx_recalc_rate,
>  };
>  
>  static const struct clk_ops clk_pll1443x_ops = {
>  	.prepare	= clk_pll14xx_prepare,
>  	.unprepare	= clk_pll14xx_unprepare,
>  	.is_prepared	= clk_pll14xx_is_prepared,
> -	.recalc_rate	= clk_pll1443x_recalc_rate,
> +	.recalc_rate	= clk_pll14xx_recalc_rate,
>  	.round_rate	= clk_pll14xx_round_rate,
>  	.set_rate	= clk_pll1443x_set_rate,
>  };
> -- 
> 2.30.2
>