zephyr/drivers/counter/counter_dw_timer.c

404 lines
11 KiB
C

/*
* Copyright (c) 2023 Intel Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT snps_dw_timers
#include <zephyr/device.h>
#include <zephyr/drivers/counter.h>
#include <zephyr/spinlock.h>
#include <zephyr/logging/log.h>
#include <zephyr/drivers/reset.h>
#include <zephyr/drivers/clock_control.h>
LOG_MODULE_REGISTER(dw_timer, CONFIG_COUNTER_LOG_LEVEL);
static int counter_dw_timer_get_value(const struct device *timer_dev, uint32_t *ticks);
/* DW APB timer register offsets */
#define LOADCOUNT_OFST 0x0
#define CURRENTVAL_OFST 0x4
#define CONTROLREG_OFST 0x8
#define EOI_OFST 0xc
#define INTSTAT_OFST 0x10
/* free running mode value */
#define FREE_RUNNING_MODE_VAL 0xFFFFFFFFUL
/* DW APB timer control flags */
#define TIMER_CONTROL_ENABLE_BIT 0
#define TIMER_MODE_BIT 1
#define TIMER_INTR_MASK_BIT 2
/* DW APB timer modes */
#define USER_DEFINED_MODE 1
#define FREE_RUNNING_MODE 0
#define DEV_CFG(_dev) ((const struct counter_dw_timer_config *)(_dev)->config)
#define DEV_DATA(_dev) ((struct counter_dw_timer_drv_data *const)(_dev)->data)
/* Device Configuration */
struct counter_dw_timer_config {
struct counter_config_info info;
DEVICE_MMIO_NAMED_ROM(timer_mmio);
/* clock frequency of timer */
uint32_t freq;
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(clocks)
/* clock controller dev instance */
const struct device *clk_dev;
/* identifier for timer to get clock freq from clk manager */
clock_control_subsys_t clkid;
#endif
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(resets)
/* reset controller device configuration*/
const struct reset_dt_spec reset;
#endif
/* interrupt config function ptr */
void (*irq_config)(void);
};
/* Driver data */
struct counter_dw_timer_drv_data {
/* mmio address mapping info */
DEVICE_MMIO_NAMED_RAM(timer_mmio);
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(clocks)
/* clock frequency of timer */
uint32_t freq;
#endif
/* spin lock to protect user data */
struct k_spinlock lock;
/* top callback function */
counter_top_callback_t top_cb;
/* alarm callback function */
counter_alarm_callback_t alarm_cb;
/* private user data */
void *prv_data;
};
static void counter_dw_timer_irq_handler(const struct device *timer_dev)
{
uint32_t ticks = 0;
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
k_spinlock_key_t key;
counter_alarm_callback_t alarm_cb = data->alarm_cb;
/* read EOI register to clear interrupt flag */
sys_read32(reg_base + EOI_OFST);
counter_dw_timer_get_value(timer_dev, &ticks);
key = k_spin_lock(&data->lock);
/* In case of alarm, mask interrupt and disable the callback. User
* can configure the alarm in same context within callback function.
*/
if (data->alarm_cb) {
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_INTR_MASK_BIT);
data->alarm_cb = NULL;
alarm_cb(timer_dev, 0, ticks, data->prv_data);
} else if (data->top_cb) {
data->top_cb(timer_dev, data->prv_data);
}
k_spin_unlock(&data->lock, key);
}
static int counter_dw_timer_start(const struct device *dev)
{
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(dev, timer_mmio);
/* disable timer before starting in free-running mode */
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
/* starting timer in free running mode */
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_MODE_BIT);
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_INTR_MASK_BIT);
sys_write32(FREE_RUNNING_MODE_VAL, reg_base + LOADCOUNT_OFST);
/* enable timer */
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
return 0;
}
int counter_dw_timer_disable(const struct device *dev)
{
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(dev, timer_mmio);
/* stop timer */
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
return 0;
}
static uint32_t counter_dw_timer_get_top_value(const struct device *timer_dev)
{
uint32_t top_val = 0;
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
/* get the current top value from load count register */
top_val = sys_read32(reg_base + LOADCOUNT_OFST);
return top_val;
}
static int counter_dw_timer_get_value(const struct device *timer_dev, uint32_t *ticks)
{
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
/* current value of the current value register */
*ticks = sys_read32(reg_base + CURRENTVAL_OFST);
return 0;
}
static int counter_dw_timer_set_top_value(const struct device *timer_dev,
const struct counter_top_cfg *top_cfg)
{
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
k_spinlock_key_t key;
if (top_cfg == NULL) {
LOG_ERR("Invalid top value configuration");
return -EINVAL;
}
/* top value cannot be updated without reset */
if (top_cfg->flags & COUNTER_TOP_CFG_DONT_RESET) {
LOG_ERR("Updating top value without reset is not supported");
return -ENOTSUP;
}
key = k_spin_lock(&data->lock);
/* top value cannot be updated if the alarm is active */
if (data->alarm_cb) {
k_spin_unlock(&data->lock, key);
LOG_ERR("Top value cannot be updated, alarm is active!");
return -EBUSY;
}
if (!top_cfg->callback) {
/* mask an interrupt if callback is not passed */
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_INTR_MASK_BIT);
} else {
/* unmask interrupt if callback is passed */
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_INTR_MASK_BIT);
}
data->top_cb = top_cfg->callback;
data->prv_data = top_cfg->user_data;
/* top value can be loaded only when timer is stopped and re-enabled */
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
/* configuring timer in user-defined mode */
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_MODE_BIT);
/* set new top value */
sys_write32(top_cfg->ticks, reg_base + LOADCOUNT_OFST);
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
k_spin_unlock(&data->lock, key);
return 0;
}
static int counter_dw_timer_set_alarm(const struct device *timer_dev, uint8_t chan_id,
const struct counter_alarm_cfg *alarm_cfg)
{
ARG_UNUSED(chan_id);
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
k_spinlock_key_t key;
if (alarm_cfg == NULL) {
LOG_ERR("Invalid alarm configuration");
return -EINVAL;
}
/* Alarm callback is mandatory */
if (!alarm_cfg->callback) {
LOG_ERR("Alarm callback function cannot be null");
return -EINVAL;
}
/* absolute alarm is not supported as interrupts are triggered
* only when the counter reaches 0(downcounter)
*/
if (alarm_cfg->flags & COUNTER_ALARM_CFG_ABSOLUTE) {
LOG_ERR("Absolute alarm is not supported");
return -ENOTSUP;
}
key = k_spin_lock(&data->lock);
/* check if alarm is already active */
if (data->alarm_cb != NULL) {
LOG_ERR("Alarm is already active\n");
k_spin_unlock(&data->lock, key);
return -EBUSY;
}
data->alarm_cb = alarm_cfg->callback;
data->prv_data = alarm_cfg->user_data;
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
/* start timer in user-defined mode */
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_MODE_BIT);
sys_clear_bit(reg_base + CONTROLREG_OFST, TIMER_INTR_MASK_BIT);
sys_write32(alarm_cfg->ticks, reg_base + LOADCOUNT_OFST);
sys_set_bit(reg_base + CONTROLREG_OFST, TIMER_CONTROL_ENABLE_BIT);
k_spin_unlock(&data->lock, key);
return 0;
}
static int counter_dw_timer_cancel_alarm(const struct device *timer_dev, uint8_t chan_id)
{
ARG_UNUSED(chan_id);
uintptr_t reg_base = DEVICE_MMIO_NAMED_GET(timer_dev, timer_mmio);
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
k_spinlock_key_t key;
key = k_spin_lock(&data->lock);
sys_write32(0, reg_base + CONTROLREG_OFST);
data->alarm_cb = NULL;
data->prv_data = NULL;
k_spin_unlock(&data->lock, key);
return 0;
}
uint32_t counter_dw_timer_get_freq(const struct device *timer_dev)
{
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(clocks)
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
return data->freq;
#else
const struct counter_dw_timer_config *config = DEV_CFG(timer_dev);
return config->freq;
#endif
}
static const struct counter_driver_api dw_timer_driver_api = {
.start = counter_dw_timer_start,
.stop = counter_dw_timer_disable,
.get_value = counter_dw_timer_get_value,
.set_top_value = counter_dw_timer_set_top_value,
.get_top_value = counter_dw_timer_get_top_value,
.set_alarm = counter_dw_timer_set_alarm,
.cancel_alarm = counter_dw_timer_cancel_alarm,
.get_freq = counter_dw_timer_get_freq,
};
static int counter_dw_timer_init(const struct device *timer_dev)
{
DEVICE_MMIO_NAMED_MAP(timer_dev, timer_mmio, K_MEM_CACHE_NONE);
const struct counter_dw_timer_config *timer_config = DEV_CFG(timer_dev);
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(clocks) || DT_ANY_INST_HAS_PROP_STATUS_OKAY(resets)
int ret;
#endif
/*
* get clock rate from clock_frequency property if valid,
* otherwise, get clock rate from clock manager
*/
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(clocks)
struct counter_dw_timer_drv_data *const data = DEV_DATA(timer_dev);
if (!device_is_ready(timer_config->clk_dev)) {
LOG_ERR("clock controller device not ready");
return -ENODEV;
}
ret = clock_control_get_rate(timer_config->clk_dev,
timer_config->clkid, &data->freq);
if (ret != 0) {
LOG_ERR("Unable to get clock rate: err:%d", ret);
return ret;
}
#endif
/* Reset timer only if reset controller driver is supported */
#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(resets)
if (timer_config->reset.dev != NULL) {
if (!device_is_ready(timer_config->reset.dev)) {
LOG_ERR("Reset controller device not ready");
return -ENODEV;
}
ret = reset_line_toggle(timer_config->reset.dev, timer_config->reset.id);
if (ret != 0) {
LOG_ERR("Timer reset failed");
return ret;
}
}
#endif
timer_config->irq_config();
return 0;
}
#define DW_SNPS_TIMER_CLOCK_RATE_INIT(inst) \
COND_CODE_1(DT_INST_NODE_HAS_PROP(inst, clock_frequency), \
( \
.freq = DT_INST_PROP(inst, clock_frequency), \
), \
( \
.freq = 0, \
.clk_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(inst)), \
.clkid = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(inst, clkid), \
) \
)
#define DW_SNPS_TIMER_SNPS_RESET_SPEC_INIT(inst) \
.reset = RESET_DT_SPEC_INST_GET(inst), \
#define CREATE_DW_TIMER_DEV(inst) \
static void counter_dw_timer_irq_config_##inst(void); \
static struct counter_dw_timer_drv_data timer_data_##inst; \
static const struct counter_dw_timer_config timer_config_##inst = { \
DEVICE_MMIO_NAMED_ROM_INIT(timer_mmio, DT_DRV_INST(inst)), \
DW_SNPS_TIMER_CLOCK_RATE_INIT(inst) \
.info = { \
.max_top_value = UINT32_MAX, \
.channels = 1, \
}, \
IF_ENABLED(DT_INST_NODE_HAS_PROP(inst, resets), \
(DW_SNPS_TIMER_SNPS_RESET_SPEC_INIT(inst))) \
.irq_config = counter_dw_timer_irq_config_##inst, \
}; \
DEVICE_DT_INST_DEFINE(inst, \
counter_dw_timer_init, \
NULL, &timer_data_##inst, \
&timer_config_##inst, POST_KERNEL, \
CONFIG_COUNTER_INIT_PRIORITY, \
&dw_timer_driver_api); \
static void counter_dw_timer_irq_config_##inst(void) \
{ \
IRQ_CONNECT(DT_INST_IRQN(inst), \
DT_INST_IRQ(inst, priority), \
counter_dw_timer_irq_handler, \
DEVICE_DT_INST_GET(inst), 0); \
irq_enable(DT_INST_IRQN(inst)); \
}
DT_INST_FOREACH_STATUS_OKAY(CREATE_DW_TIMER_DEV);