linux/drivers/clk/meson/clk-cpu-dyndiv.c

74 lines
2.2 KiB
C

// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
* Copyright (c) 2019 BayLibre, SAS.
* Author: Neil Armstrong <narmstrong@baylibre.com>
*/
#include <linux/clk-provider.h>
#include <linux/module.h>
#include "clk-regmap.h"
#include "clk-cpu-dyndiv.h"
static inline struct meson_clk_cpu_dyndiv_data *
meson_clk_cpu_dyndiv_data(struct clk_regmap *clk)
{
return (struct meson_clk_cpu_dyndiv_data *)clk->data;
}
static unsigned long meson_clk_cpu_dyndiv_recalc_rate(struct clk_hw *hw,
unsigned long prate)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_cpu_dyndiv_data *data = meson_clk_cpu_dyndiv_data(clk);
return divider_recalc_rate(hw, prate,
meson_parm_read(clk->map, &data->div),
NULL, 0, data->div.width);
}
static long meson_clk_cpu_dyndiv_round_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long *prate)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_cpu_dyndiv_data *data = meson_clk_cpu_dyndiv_data(clk);
return divider_round_rate(hw, rate, prate, NULL, data->div.width, 0);
}
static int meson_clk_cpu_dyndiv_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_cpu_dyndiv_data *data = meson_clk_cpu_dyndiv_data(clk);
unsigned int val;
int ret;
ret = divider_get_val(rate, parent_rate, NULL, data->div.width, 0);
if (ret < 0)
return ret;
val = (unsigned int)ret << data->div.shift;
/* Write the SYS_CPU_DYN_ENABLE bit before changing the divider */
meson_parm_write(clk->map, &data->dyn, 1);
/* Update the divider while removing the SYS_CPU_DYN_ENABLE bit */
return regmap_update_bits(clk->map, data->div.reg_off,
SETPMASK(data->div.width, data->div.shift) |
SETPMASK(data->dyn.width, data->dyn.shift),
val);
};
const struct clk_ops meson_clk_cpu_dyndiv_ops = {
.recalc_rate = meson_clk_cpu_dyndiv_recalc_rate,
.round_rate = meson_clk_cpu_dyndiv_round_rate,
.set_rate = meson_clk_cpu_dyndiv_set_rate,
};
EXPORT_SYMBOL_GPL(meson_clk_cpu_dyndiv_ops);
MODULE_DESCRIPTION("Amlogic CPU Dynamic Clock divider");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
MODULE_LICENSE("GPL v2");