[U-Boot] [i.MX8MM+CCF 10/41] divider set rate supporrt

Lukasz Majewski lukma at denx.de
Mon May 6 22:08:28 UTC 2019


On Tue, 30 Apr 2019 10:18:05 +0000
Peng Fan <peng.fan at nxp.com> wrote:

Please state the exact SHA1 or tag when porting the code from Linux
kernel.

> Signed-off-by: Peng Fan <peng.fan at nxp.com>
> ---
>  drivers/clk/clk-divider.c | 88
> +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88
> insertions(+)
> 
> diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
> index 2f09e0bb58..8615f9815d 100644
> --- a/drivers/clk/clk-divider.c
> +++ b/drivers/clk/clk-divider.c
> @@ -18,6 +18,7 @@
>  #include <dm/lists.h>
>  #include <dm/device-internal.h>
>  #include <linux/clk-provider.h>
> +#include <linux/log2.h>
>  #include <div64.h>
>  #include <clk.h>
>  #include "clk.h"
> @@ -81,8 +82,95 @@ static ulong clk_divider_recalc_rate(struct clk
> *clk) divider->flags, divider->width);
>  }
>  
> +static bool _is_valid_table_div(const struct clk_div_table *table,
> +				unsigned int div)
> +{
> +	const struct clk_div_table *clkt;
> +
> +	for (clkt = table; clkt->div; clkt++)
> +		if (clkt->div == div)
> +			return true;
> +	return false;
> +}
> +
> +static bool _is_valid_div(const struct clk_div_table *table,
> unsigned int div,
> +			  unsigned long flags)
> +{
> +	if (flags & CLK_DIVIDER_POWER_OF_TWO)
> +		return is_power_of_2(div);
> +	if (table)
> +		return _is_valid_table_div(table, div);
> +	return true;
> +}
> +
> +static unsigned int _get_table_val(const struct clk_div_table *table,
> +				   unsigned int div)
> +{
> +	const struct clk_div_table *clkt;
> +
> +	for (clkt = table; clkt->div; clkt++)
> +		if (clkt->div == div)
> +			return clkt->val;
> +	return 0;
> +}
> +
> +static unsigned int _get_val(const struct clk_div_table *table,
> +			     unsigned int div, unsigned long flags,
> u8 width) +{
> +	if (flags & CLK_DIVIDER_ONE_BASED)
> +		return div;
> +	if (flags & CLK_DIVIDER_POWER_OF_TWO)
> +		return __ffs(div);
> +	if (flags & CLK_DIVIDER_MAX_AT_ZERO)
> +		return (div == clk_div_mask(width) + 1) ? 0 : div;
> +	if (table)
> +		return  _get_table_val(table, div);
> +	return div - 1;
> +}
> +int divider_get_val(unsigned long rate, unsigned long parent_rate,
> +		    const struct clk_div_table *table, u8 width,
> +		    unsigned long flags)
> +{
> +	unsigned int div, value;
> +
> +	div = DIV_ROUND_UP_ULL((u64)parent_rate, rate);
> +
> +	if (!_is_valid_div(table, div, flags))
> +		return -EINVAL;
> +
> +	value = _get_val(table, div, flags, width);
> +
> +	return min_t(unsigned int, value, clk_div_mask(width));
> +}
> +
> +static ulong clk_divider_set_rate(struct clk *clk, unsigned long
> rate) +{
> +	struct clk_divider *divider =
> to_clk_divider(clk_dev_binded(clk) ?
> +			(struct clk
> *)dev_get_driver_data(clk->dev) : clk);
> +	unsigned long parent_rate = clk_get_parent_rate(clk);
> +	int value;
> +	u32 val;
> +
> +	value = divider_get_val(rate, parent_rate, divider->table,
> +				divider->width, divider->flags);
> +	if (value < 0)
> +		return value;
> +
> +	if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
> +		val = clk_div_mask(divider->width) <<
> (divider->shift + 16);
> +	} else {
> +		val = readl(divider->reg);
> +		val &= ~(clk_div_mask(divider->width) <<
> divider->shift);
> +	}
> +	val |= (u32)value << divider->shift;
> +	writel(val, divider->reg);
> +
> +	return clk_get_rate(clk);
> +}
> +
>  const struct clk_ops clk_divider_ops = {
>  	.get_rate = clk_divider_recalc_rate,
> +	.set_rate = clk_divider_set_rate,
>  };
>  
>  static struct clk *_register_divider(struct device *dev, const char
> *name,




Best regards,

Lukasz Majewski

--

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