zephyr/drivers/clock_control/clock_control_si32_pll.c

140 lines
3.5 KiB
C

/*
* Copyright (c) 2024 GARDENA GmbH
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT silabs_si32_pll
#include <stdint.h>
#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/clock_control.h>
#include <SI32_CLKCTRL_A_Type.h>
#include <SI32_PLL_A_Type.h>
#include <si32_device.h>
#define LOG_LEVEL LOG_LEVEL_DBG
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(pll);
struct clock_control_si32_pll_config {
SI32_PLL_A_Type *pll;
};
struct clock_control_si32_pll_data {
uint32_t freq;
};
static int clock_control_si32_pll_on(const struct device *dev, clock_control_subsys_t sys)
{
const struct clock_control_si32_pll_config *config = dev->config;
struct clock_control_si32_pll_data *data = dev->data;
if (data->freq == 0) {
return -ENOTSUP;
}
uint32_t dco_range;
if (data->freq > 80000000) {
dco_range = 4;
} else if (data->freq > 76500000) {
dco_range = 4;
} else if (data->freq > 62000000) {
dco_range = 3;
} else if (data->freq > 49500000) {
dco_range = 2;
} else if (data->freq > 35000000) {
dco_range = 1;
} else if (data->freq > 23000000) {
dco_range = 0;
} else {
return -ENOTSUP;
}
/* lposc0div */
const uint32_t source_clock_freq = 2500000;
const uint32_t div_m = 100;
const uint32_t div_n = (data->freq / source_clock_freq) * (div_m + 1) - 1;
if (div_n < 32 || div_n > 4095) {
return -ENOTSUP;
}
/* Setup PLL to lock to requested frequency */
SI32_PLL_A_initialize(config->pll, 0x00, 0x00, 0x00, 0x000FFF0);
SI32_PLL_A_set_numerator(config->pll, div_n);
SI32_PLL_A_set_denominator(config->pll, div_m);
/* TODO: support other clock sources */
SI32_PLL_A_select_reference_clock_source_lp0oscdiv(config->pll);
/* Wait for lock */
SI32_PLL_A_select_disable_dco_output(config->pll);
SI32_PLL_A_set_frequency_adjuster_value(config->pll, 0xFFF);
SI32_PLL_A_set_output_frequency_range(config->pll, dco_range);
/* Lock and block for result */
SI32_PLL_A_select_dco_frequency_lock_mode(config->pll);
while (!(SI32_PLL_A_is_locked(config->pll) ||
SI32_PLL_A_is_saturation_low_interrupt_pending(config->pll) ||
SI32_PLL_A_is_saturation_high_interrupt_pending(config->pll)))
;
return 0;
}
static int clock_control_si32_pll_off(const struct device *dev, clock_control_subsys_t sys)
{
return -ENOTSUP;
}
static int clock_control_si32_pll_get_rate(const struct device *dev, clock_control_subsys_t sys,
uint32_t *rate)
{
struct clock_control_si32_pll_data *data = dev->data;
*rate = data->freq;
return 0;
}
static int clock_control_si32_pll_set_rate(const struct device *dev, clock_control_subsys_t sys,
clock_control_subsys_rate_t rate_)
{
struct clock_control_si32_pll_data *data = dev->data;
const uint32_t *rate = rate_;
data->freq = *rate;
return 0;
}
static struct clock_control_driver_api clock_control_si32_pll_api = {
.on = clock_control_si32_pll_on,
.off = clock_control_si32_pll_off,
.get_rate = clock_control_si32_pll_get_rate,
.set_rate = clock_control_si32_pll_set_rate,
};
static int clock_control_si32_pll_init(const struct device *dev)
{
SI32_CLKCTRL_A_enable_apb_to_modules_0(SI32_CLKCTRL_0, SI32_CLKCTRL_A_APBCLKG0_PLL0);
return 0;
}
static const struct clock_control_si32_pll_config config = {
.pll = (SI32_PLL_A_Type *)DT_REG_ADDR(DT_NODELABEL(pll0)),
};
static struct clock_control_si32_pll_data data = {
.freq = 0,
};
DEVICE_DT_INST_DEFINE(0, clock_control_si32_pll_init, NULL, &data, &config, PRE_KERNEL_1,
CONFIG_CLOCK_CONTROL_INIT_PRIORITY, &clock_control_si32_pll_api);