[PATCH v6 5/7] clk: samsung: Add set_rate() clk_ops for PLL36xx

Tomasz Figa tomasz.figa at gmail.com
Wed Jun 19 13:05:05 EDT 2013


On Monday 10 of June 2013 18:54:17 Yadwinder Singh Brar wrote:
> From: Vikas Sajjan <vikas.sajjan at linaro.org>
> 
> This patch adds set_rate and round_rate clk_ops for PLL36xx
> 
> Reviewed-by: Tomasz Figa <t.figa at samsung.com>
> Reviewed-by: Doug Anderson <dianders at chromium.org>
> Signed-off-by: Vikas Sajjan <vikas.sajjan at linaro.org>
> ---
>  drivers/clk/samsung/clk-pll.c |   79
> ++++++++++++++++++++++++++++++++++++++++- 1 files changed, 78
> insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/clk/samsung/clk-pll.c
> b/drivers/clk/samsung/clk-pll.c index e3e7f0c..2197004 100644
> --- a/drivers/clk/samsung/clk-pll.c
> +++ b/drivers/clk/samsung/clk-pll.c
> @@ -160,6 +160,8 @@ static const struct clk_ops
> samsung_pll35xx_clk_min_ops = { /*
>   * PLL36xx Clock Type
>   */
> +/* Maximum lock time can be 3000 * PDIV cycles */
> +#define PLL36XX_LOCK_FACTOR    (3000)
> 
>  #define PLL36XX_KDIV_MASK	(0xFFFF)
>  #define PLL36XX_MDIV_MASK	(0x1FF)
> @@ -168,6 +170,8 @@ static const struct clk_ops
> samsung_pll35xx_clk_min_ops = { #define PLL36XX_MDIV_SHIFT	(16)
>  #define PLL36XX_PDIV_SHIFT	(8)
>  #define PLL36XX_SDIV_SHIFT	(0)
> +#define PLL36XX_KDIV_SHIFT	(0)
> +#define PLL36XX_LOCK_STAT_SHIFT	(29)
> 
>  static unsigned long samsung_pll36xx_recalc_rate(struct clk_hw *hw,
>  				unsigned long parent_rate)
> @@ -190,8 +194,78 @@ static unsigned long
> samsung_pll36xx_recalc_rate(struct clk_hw *hw, return (unsigned
> long)fvco;
>  }
> 
> +static inline bool samsung_pll36xx_mpk_change(
> +	const struct samsung_pll_rate_table *rate, u32 pll_con0, u32 
pll_con1)
> +{
> +	u32 old_mdiv, old_pdiv, old_kdiv;
> +
> +	old_mdiv = (pll_con0 >> PLL36XX_MDIV_SHIFT) & PLL36XX_MDIV_MASK;
> +	old_pdiv = (pll_con0 >> PLL36XX_PDIV_SHIFT) & PLL36XX_PDIV_MASK;
> +	old_kdiv = (pll_con1 >> PLL36XX_KDIV_SHIFT) & PLL36XX_KDIV_MASK;
> +
> +	return (rate->mdiv != old_mdiv || rate->pdiv != old_pdiv ||
> +		rate->kdiv != old_kdiv);
> +}
> +
> +static int samsung_pll36xx_set_rate(struct clk_hw *hw, unsigned long
> drate, +					unsigned long parent_rate)
> +{
> +	struct samsung_clk_pll *pll = to_clk_pll(hw);
> +	u32 tmp, pll_con0, pll_con1;
> +	const struct samsung_pll_rate_table *rate;
> +
> +	rate = samsung_get_pll_settings(pll, drate);
> +	if (!rate) {
> +		pr_err("%s: Invalid rate : %lu for pll clk %s\n", 
__func__,
> +			drate, __clk_get_name(hw->clk));
> +		return -EINVAL;
> +	}
> +
> +	pll_con0 = __raw_readl(pll->con_reg);
> +	pll_con1 = __raw_readl(pll->con_reg + 4);

Please define offset constants for these two registers.

Otherwise looks good.

Best regards,
Tomasz

> +
> +	if (!(samsung_pll36xx_mpk_change(rate, pll_con0, pll_con1))) {
> +		/* If only s change, change just s value only*/
> +		pll_con0 &= ~(PLL36XX_SDIV_MASK << PLL36XX_SDIV_SHIFT);
> +		pll_con0 |= (rate->sdiv << PLL36XX_SDIV_SHIFT);
> +		__raw_writel(pll_con0, pll->con_reg);
> +
> +		return 0;
> +	}
> +
> +	/* Set PLL lock time. */
> +	__raw_writel(rate->pdiv * PLL36XX_LOCK_FACTOR, pll->lock_reg);
> +
> +	 /* Change PLL PMS values */
> +	pll_con0 &= ~((PLL36XX_MDIV_MASK << PLL36XX_MDIV_SHIFT) |
> +			(PLL36XX_PDIV_MASK << PLL36XX_PDIV_SHIFT) |
> +			(PLL36XX_SDIV_MASK << PLL36XX_SDIV_SHIFT));
> +	pll_con0 |= (rate->mdiv << PLL36XX_MDIV_SHIFT) |
> +			(rate->pdiv << PLL36XX_PDIV_SHIFT) |
> +			(rate->sdiv << PLL36XX_SDIV_SHIFT);
> +	__raw_writel(pll_con0, pll->con_reg);
> +
> +	pll_con1 &= ~(PLL36XX_KDIV_MASK << PLL36XX_KDIV_SHIFT);
> +	pll_con1 |= rate->kdiv << PLL36XX_KDIV_SHIFT;
> +	__raw_writel(pll_con1, pll->con_reg + 4);
> +
> +	/* wait_lock_time */
> +	do {
> +		cpu_relax();
> +		tmp = __raw_readl(pll->con_reg);
> +	} while (!(tmp & (1 << PLL36XX_LOCK_STAT_SHIFT)));
> +
> +	return 0;
> +}
> +
>  static const struct clk_ops samsung_pll36xx_clk_ops = {
>  	.recalc_rate = samsung_pll36xx_recalc_rate,
> +	.set_rate = samsung_pll36xx_set_rate,
> +	.round_rate = samsung_pll_round_rate,
> +};
> +
> +static const struct clk_ops samsung_pll36xx_clk_min_ops = {
> +	.recalc_rate = samsung_pll36xx_recalc_rate,
>  };
> 
>  /*
> @@ -494,7 +568,10 @@ void __init samsung_clk_register_pll(struct
> samsung_pll_clock *clk_list, /* clk_ops for 36xx and 2650 are similar
> */
>  		case pll_36xx:
>  		case pll_2650:
> -			init.ops = &samsung_pll36xx_clk_ops;
> +			if (!pll->rate_table)
> +				init.ops = &samsung_pll36xx_clk_min_ops;
> +			else
> +				init.ops = &samsung_pll36xx_clk_ops;
>  			break;
>  		default:
>  			pr_warn("%s: Unknown pll type for pll clk %s\n",



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