zephyr/drivers/counter/counter_sam0_tc32.c

460 lines
11 KiB
C

/*
* Copyright (c) 2019 Derek Hageman <hageman@inthat.cloud>
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <drivers/counter.h>
#include <device.h>
#include <soc.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(counter_sam0_tc32, CONFIG_COUNTER_LOG_LEVEL);
struct counter_sam0_tc32_ch_data {
counter_alarm_callback_t callback;
void *user_data;
};
struct counter_sam0_tc32_data {
counter_top_callback_t top_cb;
void *top_user_data;
struct counter_sam0_tc32_ch_data ch;
};
struct counter_sam0_tc32_config {
struct counter_config_info info;
TcCount32 *regs;
#ifdef MCLK
volatile u32_t *mclk;
u32_t mclk_mask;
u16_t gclk_id;
#else
u32_t pm_apbcmask;
u16_t gclk_clkctrl_id;
#endif
u16_t prescaler;
void (*irq_config_func)(struct device *dev);
};
#define DEV_CFG(dev) ((const struct counter_sam0_tc32_config *const) \
(dev)->config->config_info)
#define DEV_DATA(dev) ((struct counter_sam0_tc32_data *const) \
(dev)->driver_data)
static void wait_synchronization(TcCount32 *regs)
{
#if defined(TC_SYNCBUSY_MASK)
/* SYNCBUSY is a register */
while ((regs->SYNCBUSY.reg & TC_SYNCBUSY_MASK) != 0) {
}
#elif defined(TC_STATUS_SYNCBUSY)
/* SYNCBUSY is a bit */
while ((regs->STATUS.reg & TC_STATUS_SYNCBUSY) != 0) {
}
#else
#error Unsupported device
#endif
}
static void read_synchronize_count(TcCount32 *regs)
{
#if defined(TC_READREQ_RREQ)
regs->READREQ.reg = TC_READREQ_RREQ |
TC_READREQ_ADDR(TC_COUNT32_COUNT_OFFSET);
wait_synchronization(regs);
#elif defined(TC_CTRLBSET_CMD_READSYNC)
regs->CTRLBSET.reg = TC_CTRLBSET_CMD_READSYNC;
wait_synchronization(regs);
#else
ARG_UNUSED(regs);
#endif
}
static int counter_sam0_tc32_start(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
/*
* This will also reset the current counter value if it's
* already running.
*/
tc->CTRLBSET.reg = TC_CTRLBSET_CMD_RETRIGGER;
wait_synchronization(tc);
return 0;
}
static int counter_sam0_tc32_stop(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
/*
* The older (pre SAML1x) manuals claim the counter retains its
* value on stop, but this doesn't actually seem to happen.
* The SAML1x manual says it resets, which is what the SAMD21
* counter actually appears to do.
*/
tc->CTRLBSET.reg = TC_CTRLBSET_CMD_STOP;
wait_synchronization(tc);
return 0;
}
static u32_t counter_sam0_tc32_read(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
read_synchronize_count(tc);
return tc->COUNT.reg;
}
static void counter_sam0_tc32_relative_alarm(struct device *dev, u32_t ticks)
{
struct counter_sam0_tc32_data *data = DEV_DATA(dev);
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
u32_t before;
u32_t target;
u32_t after;
u32_t max;
read_synchronize_count(tc);
before = tc->COUNT.reg;
target = before + ticks;
max = tc->CC[0].reg;
if (target > max) {
target -= max;
}
tc->CC[1].reg = target;
wait_synchronization(tc);
tc->INTFLAG.reg = TC_INTFLAG_MC1;
read_synchronize_count(tc);
after = tc->COUNT.reg;
/* Pending now, so no further checking required */
if (tc->INTFLAG.bit.MC1) {
goto out_future;
}
/*
* Check if we missed the interrupt and call the handler
* immediately if we did.
*/
if (after < target) {
goto out_future;
}
/* Check wrapped */
if (target < before && after >= before) {
goto out_future;
}
counter_alarm_callback_t cb = data->ch.callback;
tc->INTENCLR.reg = TC_INTENCLR_MC1;
tc->INTFLAG.reg = TC_INTFLAG_MC1;
data->ch.callback = NULL;
cb(dev, 0, target, data->ch.user_data);
return;
out_future:
tc->INTENSET.reg = TC_INTFLAG_MC1;
}
static int counter_sam0_tc32_set_alarm(struct device *dev, u8_t chan_id,
const struct counter_alarm_cfg *alarm_cfg)
{
struct counter_sam0_tc32_data *data = DEV_DATA(dev);
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
ARG_UNUSED(chan_id);
if (alarm_cfg->ticks > tc->CC[0].reg) {
return -EINVAL;
}
int key = irq_lock();
if (data->ch.callback) {
irq_unlock(key);
return -EBUSY;
}
data->ch.callback = alarm_cfg->callback;
data->ch.user_data = alarm_cfg->user_data;
if ((alarm_cfg->flags & COUNTER_ALARM_CFG_ABSOLUTE) != 0) {
tc->CC[1].reg = alarm_cfg->ticks;
wait_synchronization(tc);
tc->INTFLAG.reg = TC_INTFLAG_MC1;
tc->INTENSET.reg = TC_INTFLAG_MC1;
} else {
counter_sam0_tc32_relative_alarm(dev, alarm_cfg->ticks);
}
irq_unlock(key);
return 0;
}
static int counter_sam0_tc32_cancel_alarm(struct device *dev, u8_t chan_id)
{
struct counter_sam0_tc32_data *data = DEV_DATA(dev);
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
int key = irq_lock();
ARG_UNUSED(chan_id);
data->ch.callback = NULL;
tc->INTENCLR.reg = TC_INTENCLR_MC1;
tc->INTFLAG.reg = TC_INTFLAG_MC1;
irq_unlock(key);
return 0;
}
static int counter_sam0_tc32_set_top_value(struct device *dev,
const struct counter_top_cfg *top_cfg)
{
struct counter_sam0_tc32_data *data = DEV_DATA(dev);
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
int err = 0;
int key = irq_lock();
if (data->ch.callback) {
irq_unlock(key);
return -EBUSY;
}
if (top_cfg->callback) {
data->top_cb = top_cfg->callback;
data->top_user_data = top_cfg->user_data;
tc->INTENSET.reg = TC_INTFLAG_MC0;
} else {
tc->INTENCLR.reg = TC_INTFLAG_MC0;
}
tc->CC[0].reg = top_cfg->ticks;
if (top_cfg->flags & COUNTER_TOP_CFG_DONT_RESET) {
/*
* Top trigger is on equality of the rising edge only, so
* manually reset it if the counter has missed the new top.
*/
if (counter_sam0_tc32_read(dev) >= top_cfg->ticks) {
err = -ETIME;
if (top_cfg->flags & COUNTER_TOP_CFG_RESET_WHEN_LATE) {
tc->CTRLBSET.reg = TC_CTRLBSET_CMD_RETRIGGER;
}
}
} else {
tc->CTRLBSET.reg = TC_CTRLBSET_CMD_RETRIGGER;
}
wait_synchronization(tc);
tc->INTFLAG.reg = TC_INTFLAG_MC0;
irq_unlock(key);
return err;
}
static u32_t counter_sam0_tc32_get_pending_int(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
return tc->INTFLAG.reg & (TC_INTFLAG_MC0 | TC_INTFLAG_MC1);
}
static u32_t counter_sam0_tc32_get_top_value(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
/*
* Unsync read is safe here because we're not using
* capture mode, so things are only set from the CPU
* end.
*/
return tc->CC[0].reg;
}
static u32_t counter_sam0_tc32_get_max_relative_alarm(struct device *dev)
{
return counter_sam0_tc32_get_top_value(dev) - 1;
}
static void counter_sam0_tc32_isr(void *arg)
{
struct device *dev = (struct device *)arg;
struct counter_sam0_tc32_data *data = DEV_DATA(dev);
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
u8_t status = tc->INTFLAG.reg;
/* Acknowledge all interrupts */
tc->INTFLAG.reg = status;
if (status & TC_INTFLAG_MC1) {
if (data->ch.callback) {
counter_alarm_callback_t cb = data->ch.callback;
tc->INTENCLR.reg = TC_INTENCLR_MC1;
data->ch.callback = NULL;
cb(dev, 0, tc->CC[1].reg, data->ch.user_data);
}
}
if (status & TC_INTFLAG_MC0) {
if (data->top_cb) {
data->top_cb(dev, data->top_user_data);
}
}
}
static int counter_sam0_tc32_initialize(struct device *dev)
{
const struct counter_sam0_tc32_config *const cfg = DEV_CFG(dev);
TcCount32 *tc = cfg->regs;
#ifdef MCLK
/* Enable the GCLK */
GCLK->PCHCTRL[cfg->gclk_id].reg = GCLK_PCHCTRL_GEN_GCLK0 |
GCLK_PCHCTRL_CHEN;
/* Enable TC clock in MCLK */
*cfg->mclk |= cfg->mclk_mask;
#else
/* Enable the GCLK */
GCLK->CLKCTRL.reg = cfg->gclk_clkctrl_id | GCLK_CLKCTRL_GEN_GCLK0 |
GCLK_CLKCTRL_CLKEN;
/* Enable clock in PM */
PM->APBCMASK.reg |= cfg->pm_apbcmask;
#endif
/*
* In 32 bit mode, NFRQ mode always uses MAX as the counter top, so
* use MFRQ mode which uses CC0 as the top at the expense of only
* having CC1 available for alarms.
*/
tc->CTRLA.reg = TC_CTRLA_MODE_COUNT32 |
#ifdef TC_CTRLA_WAVEGEN_MFRQ
TC_CTRLA_WAVEGEN_MFRQ |
#endif
cfg->prescaler;
wait_synchronization(tc);
#ifdef TC_WAVE_WAVEGEN_MFRQ
tc->WAVE.reg = TC_WAVE_WAVEGEN_MFRQ;
#endif
/* Disable all interrupts */
tc->INTENCLR.reg = TC_INTENCLR_MASK;
/* Set the initial top as the maximum */
tc->CC[0].reg = UINT32_MAX;
cfg->irq_config_func(dev);
tc->CTRLA.bit.ENABLE = 1;
wait_synchronization(tc);
/* Stop the counter initially */
tc->CTRLBSET.reg = TC_CTRLBSET_CMD_STOP;
wait_synchronization(tc);
return 0;
}
static const struct counter_driver_api counter_sam0_tc32_driver_api = {
.start = counter_sam0_tc32_start,
.stop = counter_sam0_tc32_stop,
.read = counter_sam0_tc32_read,
.set_alarm = counter_sam0_tc32_set_alarm,
.cancel_alarm = counter_sam0_tc32_cancel_alarm,
.set_top_value = counter_sam0_tc32_set_top_value,
.get_pending_int = counter_sam0_tc32_get_pending_int,
.get_top_value = counter_sam0_tc32_get_top_value,
.get_max_relative_alarm = counter_sam0_tc32_get_max_relative_alarm,
};
#ifdef MCLK
#define COUNTER_SAM0_TC32_CLOCK_CONTROL(n) \
.mclk = MCLK_TC##n, \
.mclk_mask = MCLK_TC##n##_MASK, \
.gclk_id = TC##n##_GCLK_ID,
#else
#define COUNTER_SAM0_TC32_CLOCK_CONTROL(n) \
.pm_apbcmask = PM_APBCMASK_TC##n, \
.gclk_clkctrl_id = UTIL_CAT(GCLK_CLKCTRL_ID_TC ## n ## _TC, \
UTIL_INC(n)),
#endif
#define COUNTER_SAM0_TC32_DEVICE(n) \
static void counter_sam0_tc32_config_##n(struct device *dev); \
static const struct counter_sam0_tc32_config \
counter_sam0_tc32_dev_config_##n = { \
.info = { \
.max_top_value = UINT32_MAX, \
.freq = SOC_ATMEL_SAM0_GCLK0_FREQ_HZ / \
CONFIG_COUNTER_SAM0_TC32_##n##_DIVISOR, \
.flags = COUNTER_CONFIG_INFO_COUNT_UP, \
.channels = 1 \
}, \
.regs = (TcCount32 *)DT_ATMEL_SAM0_TC32_TC_##n##_BASE_ADDRESS,\
COUNTER_SAM0_TC32_CLOCK_CONTROL(n) \
.prescaler = UTIL_CAT(TC_CTRLA_PRESCALER_DIV, \
CONFIG_COUNTER_SAM0_TC32_##n##_DIVISOR), \
.irq_config_func = &counter_sam0_tc32_config_##n, \
}; \
static struct counter_sam0_tc32_data counter_sam0_tc32_dev_data_##n; \
DEVICE_AND_API_INIT(counter_sam0_tc32_##n, \
DT_ATMEL_SAM0_TC32_TC_##n##_LABEL, \
&counter_sam0_tc32_initialize, \
&counter_sam0_tc32_dev_data_##n, \
&counter_sam0_tc32_dev_config_##n, PRE_KERNEL_1, \
CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&counter_sam0_tc32_driver_api); \
static void counter_sam0_tc32_config_##n(struct device *dev) \
{ \
IRQ_CONNECT(DT_ATMEL_SAM0_TC32_TC_##n##_IRQ_0, \
DT_ATMEL_SAM0_TC32_TC_##n##_IRQ_0_PRIORITY, \
counter_sam0_tc32_isr, \
DEVICE_GET(counter_sam0_tc32_##n), \
0); \
irq_enable(DT_ATMEL_SAM0_TC32_TC_##n##_IRQ_0); \
}
#if DT_ATMEL_SAM0_TC32_TC_0_BASE_ADDRESS
COUNTER_SAM0_TC32_DEVICE(0);
#endif
#if DT_ATMEL_SAM0_TC32_TC_2_BASE_ADDRESS
COUNTER_SAM0_TC32_DEVICE(2);
#endif
#if DT_ATMEL_SAM0_TC32_TC_4_BASE_ADDRESS
COUNTER_SAM0_TC32_DEVICE(4);
#endif
#if DT_ATMEL_SAM0_TC32_TC_6_BASE_ADDRESS
COUNTER_SAM0_TC32_DEVICE(6);
#endif