/* * Copyright (c) 2021 Kent Hall. * * SPDX-License-Identifier: Apache-2.0 */ #define DT_DRV_COMPAT st_stm32_counter #include #include #include #include #include #include #include #include LOG_MODULE_REGISTER(counter_timer_stm32, CONFIG_COUNTER_LOG_LEVEL); /* L0 series MCUs only have 16-bit timers and don't have below macro defined */ #ifndef IS_TIM_32B_COUNTER_INSTANCE #define IS_TIM_32B_COUNTER_INSTANCE(INSTANCE) (0) #endif /** Maximum number of timer channels. */ #define TIMER_MAX_CH 4U /** Number of channels for timer by index. */ #define NUM_CH(timx) \ (IS_TIM_CCX_INSTANCE(timx, TIM_CHANNEL_4) ? 4U : \ (IS_TIM_CCX_INSTANCE(timx, TIM_CHANNEL_3) ? 3U : \ (IS_TIM_CCX_INSTANCE(timx, TIM_CHANNEL_2) ? 2U : \ (IS_TIM_CCX_INSTANCE(timx, TIM_CHANNEL_1) ? 1U : \ 0)))) /** Channel to compare set function mapping. */ static void(*const set_timer_compare[TIMER_MAX_CH])(TIM_TypeDef *, uint32_t) = { LL_TIM_OC_SetCompareCH1, LL_TIM_OC_SetCompareCH2, LL_TIM_OC_SetCompareCH3, LL_TIM_OC_SetCompareCH4, }; /** Channel to compare get function mapping. */ #if !defined(CONFIG_SOC_SERIES_STM32MP1X) static uint32_t(*const get_timer_compare[TIMER_MAX_CH])(const TIM_TypeDef *) = { LL_TIM_OC_GetCompareCH1, LL_TIM_OC_GetCompareCH2, LL_TIM_OC_GetCompareCH3, LL_TIM_OC_GetCompareCH4, }; #else static uint32_t(*const get_timer_compare[TIMER_MAX_CH])(TIM_TypeDef *) = { LL_TIM_OC_GetCompareCH1, LL_TIM_OC_GetCompareCH2, LL_TIM_OC_GetCompareCH3, LL_TIM_OC_GetCompareCH4, }; #endif /** Channel to interrupt enable function mapping. */ static void(*const enable_it[TIMER_MAX_CH])(TIM_TypeDef *) = { LL_TIM_EnableIT_CC1, LL_TIM_EnableIT_CC2, LL_TIM_EnableIT_CC3, LL_TIM_EnableIT_CC4, }; /** Channel to interrupt enable function mapping. */ static void(*const disable_it[TIMER_MAX_CH])(TIM_TypeDef *) = { LL_TIM_DisableIT_CC1, LL_TIM_DisableIT_CC2, LL_TIM_DisableIT_CC3, LL_TIM_DisableIT_CC4, }; #ifdef CONFIG_ASSERT /** Channel to interrupt enable check function mapping. */ #if !defined(CONFIG_SOC_SERIES_STM32MP1X) static uint32_t(*const check_it_enabled[TIMER_MAX_CH])(const TIM_TypeDef *) = { LL_TIM_IsEnabledIT_CC1, LL_TIM_IsEnabledIT_CC2, LL_TIM_IsEnabledIT_CC3, LL_TIM_IsEnabledIT_CC4, }; #else static uint32_t(*const check_it_enabled[TIMER_MAX_CH])(TIM_TypeDef *) = { LL_TIM_IsEnabledIT_CC1, LL_TIM_IsEnabledIT_CC2, LL_TIM_IsEnabledIT_CC3, LL_TIM_IsEnabledIT_CC4, }; #endif #endif /** Channel to interrupt flag clear function mapping. */ static void(*const clear_it_flag[TIMER_MAX_CH])(TIM_TypeDef *) = { LL_TIM_ClearFlag_CC1, LL_TIM_ClearFlag_CC2, LL_TIM_ClearFlag_CC3, LL_TIM_ClearFlag_CC4, }; struct counter_stm32_data { counter_top_callback_t top_cb; void *top_user_data; uint32_t guard_period; atomic_t cc_int_pending; uint32_t freq; }; struct counter_stm32_ch_data { counter_alarm_callback_t callback; void *user_data; }; struct counter_stm32_config { struct counter_config_info info; struct counter_stm32_ch_data *ch_data; TIM_TypeDef *timer; uint32_t prescaler; struct stm32_pclken pclken; void (*irq_config_func)(const struct device *dev); uint32_t irqn; /* Reset controller device configuration */ const struct reset_dt_spec reset; LOG_INSTANCE_PTR_DECLARE(log); }; static int counter_stm32_start(const struct device *dev) { const struct counter_stm32_config *config = dev->config; TIM_TypeDef *timer = config->timer; /* enable counter */ LL_TIM_EnableCounter(timer); return 0; } static int counter_stm32_stop(const struct device *dev) { const struct counter_stm32_config *config = dev->config; TIM_TypeDef *timer = config->timer; /* disable counter */ LL_TIM_DisableCounter(timer); return 0; } static uint32_t counter_stm32_get_top_value(const struct device *dev) { const struct counter_stm32_config *config = dev->config; return LL_TIM_GetAutoReload(config->timer); } static uint32_t counter_stm32_read(const struct device *dev) { const struct counter_stm32_config *config = dev->config; return LL_TIM_GetCounter(config->timer); } static int counter_stm32_get_value(const struct device *dev, uint32_t *ticks) { *ticks = counter_stm32_read(dev); return 0; } static uint32_t counter_stm32_ticks_add(uint32_t val1, uint32_t val2, uint32_t top) { uint32_t to_top; if (likely(IS_BIT_MASK(top))) { return (val1 + val2) & top; } to_top = top - val1; return (val2 <= to_top) ? val1 + val2 : val2 - to_top - 1U; } static uint32_t counter_stm32_ticks_sub(uint32_t val, uint32_t old, uint32_t top) { if (likely(IS_BIT_MASK(top))) { return (val - old) & top; } /* if top is not 2^n-1 */ return (val >= old) ? (val - old) : val + top + 1U - old; } static void counter_stm32_counter_stm32_set_cc_int_pending(const struct device *dev, uint8_t chan) { const struct counter_stm32_config *config = dev->config; struct counter_stm32_data *data = dev->data; atomic_or(&data->cc_int_pending, BIT(chan)); NVIC_SetPendingIRQ(config->irqn); } static int counter_stm32_set_cc(const struct device *dev, uint8_t id, const struct counter_alarm_cfg *alarm_cfg) { const struct counter_stm32_config *config = dev->config; struct counter_stm32_data *data = dev->data; __ASSERT_NO_MSG(data->guard_period < counter_stm32_get_top_value(dev)); uint32_t val = alarm_cfg->ticks; uint32_t flags = alarm_cfg->flags; bool absolute = flags & COUNTER_ALARM_CFG_ABSOLUTE; bool irq_on_late; TIM_TypeDef *timer = config->timer; uint32_t top = counter_stm32_get_top_value(dev); int err = 0; uint32_t prev_val; uint32_t now; uint32_t diff; uint32_t max_rel_val; __ASSERT(!check_it_enabled[id](timer), "Expected that CC interrupt is disabled."); /* First take care of a risk of an event coming from CC being set to * next tick. Reconfigure CC to future (now tick is the furthest * future). */ now = counter_stm32_read(dev); prev_val = get_timer_compare[id](timer); set_timer_compare[id](timer, now); clear_it_flag[id](timer); if (absolute) { max_rel_val = top - data->guard_period; irq_on_late = flags & COUNTER_ALARM_CFG_EXPIRE_WHEN_LATE; } else { /* If relative value is smaller than half of the counter range * it is assumed that there is a risk of setting value too late * and late detection algorithm must be applied. When late * setting is detected, interrupt shall be triggered for * immediate expiration of the timer. Detection is performed * by limiting relative distance between CC and counter. * * Note that half of counter range is an arbitrary value. */ irq_on_late = val < (top / 2U); /* limit max to detect short relative being set too late. */ max_rel_val = irq_on_late ? top / 2U : top; val = counter_stm32_ticks_add(now, val, top); } set_timer_compare[id](timer, val); /* decrement value to detect also case when val == counter_stm32_read(dev). Otherwise, * condition would need to include comparing diff against 0. */ diff = counter_stm32_ticks_sub(val - 1U, counter_stm32_read(dev), top); if (diff > max_rel_val) { if (absolute) { err = -ETIME; } /* Interrupt is triggered always for relative alarm and * for absolute depending on the flag. */ if (irq_on_late) { counter_stm32_counter_stm32_set_cc_int_pending(dev, id); } else { config->ch_data[id].callback = NULL; } } else { enable_it[id](timer); } return err; } static int counter_stm32_set_alarm(const struct device *dev, uint8_t chan, const struct counter_alarm_cfg *alarm_cfg) { const struct counter_stm32_config *config = dev->config; struct counter_stm32_ch_data *chdata = &config->ch_data[chan]; if (alarm_cfg->ticks > counter_stm32_get_top_value(dev)) { return -EINVAL; } if (chdata->callback) { return -EBUSY; } chdata->callback = alarm_cfg->callback; chdata->user_data = alarm_cfg->user_data; return counter_stm32_set_cc(dev, chan, alarm_cfg); } static int counter_stm32_cancel_alarm(const struct device *dev, uint8_t chan) { const struct counter_stm32_config *config = dev->config; disable_it[chan](config->timer); config->ch_data[chan].callback = NULL; return 0; } static int counter_stm32_set_top_value(const struct device *dev, const struct counter_top_cfg *cfg) { const struct counter_stm32_config *config = dev->config; TIM_TypeDef *timer = config->timer; struct counter_stm32_data *data = dev->data; int err = 0; for (int i = 0; i < counter_get_num_of_channels(dev); i++) { /* Overflow can be changed only when all alarms are * disabled. */ if (config->ch_data[i].callback) { return -EBUSY; } } LL_TIM_DisableIT_UPDATE(timer); LL_TIM_SetAutoReload(timer, cfg->ticks); LL_TIM_ClearFlag_UPDATE(timer); data->top_cb = cfg->callback; data->top_user_data = cfg->user_data; if (!(cfg->flags & COUNTER_TOP_CFG_DONT_RESET)) { LL_TIM_SetCounter(timer, 0); } else if (counter_stm32_read(dev) >= cfg->ticks) { err = -ETIME; if (cfg->flags & COUNTER_TOP_CFG_RESET_WHEN_LATE) { LL_TIM_SetCounter(timer, 0); } } if (cfg->callback) { LL_TIM_EnableIT_UPDATE(timer); } return err; } static uint32_t counter_stm32_get_pending_int(const struct device *dev) { const struct counter_stm32_config *cfg = dev->config; uint32_t pending = 0; switch (counter_get_num_of_channels(dev)) { case 4U: pending |= LL_TIM_IsActiveFlag_CC4(cfg->timer); __fallthrough; case 3U: pending |= LL_TIM_IsActiveFlag_CC3(cfg->timer); __fallthrough; case 2U: pending |= LL_TIM_IsActiveFlag_CC2(cfg->timer); __fallthrough; case 1U: pending |= LL_TIM_IsActiveFlag_CC1(cfg->timer); } return !!pending; } /** * Obtain timer clock speed. * * @param pclken Timer clock control subsystem. * @param tim_clk Where computed timer clock will be stored. * * @return 0 on success, error code otherwise. * * This function is ripped from the PWM driver; TODO handle code duplication. */ static int counter_stm32_get_tim_clk(const struct stm32_pclken *pclken, uint32_t *tim_clk) { int r; const struct device *clk; uint32_t bus_clk, apb_psc; clk = DEVICE_DT_GET(STM32_CLOCK_CONTROL_NODE); if (!device_is_ready(clk)) { return -ENODEV; } r = clock_control_get_rate(clk, (clock_control_subsys_t)pclken, &bus_clk); if (r < 0) { return r; } #if defined(CONFIG_SOC_SERIES_STM32H7X) if (pclken->bus == STM32_CLOCK_BUS_APB1) { apb_psc = STM32_D2PPRE1; } else { apb_psc = STM32_D2PPRE2; } #else if (pclken->bus == STM32_CLOCK_BUS_APB1) { #if defined(CONFIG_SOC_SERIES_STM32MP1X) apb_psc = (uint32_t)(READ_BIT(RCC->APB1DIVR, RCC_APB1DIVR_APB1DIV)); #else apb_psc = STM32_APB1_PRESCALER; #endif } #if !defined(CONFIG_SOC_SERIES_STM32F0X) && !defined(CONFIG_SOC_SERIES_STM32G0X) else { #if defined(CONFIG_SOC_SERIES_STM32MP1X) apb_psc = (uint32_t)(READ_BIT(RCC->APB2DIVR, RCC_APB2DIVR_APB2DIV)); #else apb_psc = STM32_APB2_PRESCALER; #endif } #endif #endif #if defined(RCC_DCKCFGR_TIMPRE) || defined(RCC_DCKCFGR1_TIMPRE) || \ defined(RCC_CFGR_TIMPRE) /* * There are certain series (some F4, F7 and H7) that have the TIMPRE * bit to control the clock frequency of all the timers connected to * APB1 and APB2 domains. * * Up to a certain threshold value of APB{1,2} prescaler, timer clock * equals to HCLK. This threshold value depends on TIMPRE setting * (2 if TIMPRE=0, 4 if TIMPRE=1). Above threshold, timer clock is set * to a multiple of the APB domain clock PCLK{1,2} (2 if TIMPRE=0, 4 if * TIMPRE=1). */ if (LL_RCC_GetTIMPrescaler() == LL_RCC_TIM_PRESCALER_TWICE) { /* TIMPRE = 0 */ if (apb_psc <= 2u) { LL_RCC_ClocksTypeDef clocks; LL_RCC_GetSystemClocksFreq(&clocks); *tim_clk = clocks.HCLK_Frequency; } else { *tim_clk = bus_clk * 2u; } } else { /* TIMPRE = 1 */ if (apb_psc <= 4u) { LL_RCC_ClocksTypeDef clocks; LL_RCC_GetSystemClocksFreq(&clocks); *tim_clk = clocks.HCLK_Frequency; } else { *tim_clk = bus_clk * 4u; } } #else /* * If the APB prescaler equals 1, the timer clock frequencies * are set to the same frequency as that of the APB domain. * Otherwise, they are set to twice (×2) the frequency of the * APB domain. */ if (apb_psc == 1u) { *tim_clk = bus_clk; } else { *tim_clk = bus_clk * 2u; } #endif return 0; } static int counter_stm32_init_timer(const struct device *dev) { const struct counter_stm32_config *cfg = dev->config; struct counter_stm32_data *data = dev->data; TIM_TypeDef *timer = cfg->timer; LL_TIM_InitTypeDef init; uint32_t tim_clk; int r; /* initialize clock and check its speed */ r = clock_control_on(DEVICE_DT_GET(STM32_CLOCK_CONTROL_NODE), (clock_control_subsys_t)&cfg->pclken); if (r < 0) { LOG_ERR("Could not initialize clock (%d)", r); return r; } r = counter_stm32_get_tim_clk(&cfg->pclken, &tim_clk); if (r < 0) { LOG_ERR("Could not obtain timer clock (%d)", r); return r; } data->freq = tim_clk / (cfg->prescaler + 1U); if (!device_is_ready(cfg->reset.dev)) { LOG_ERR("reset controller not ready"); return -ENODEV; } /* Reset timer to default state using RCC */ (void)reset_line_toggle_dt(&cfg->reset); /* config/enable IRQ */ cfg->irq_config_func(dev); /* initialize timer */ LL_TIM_StructInit(&init); init.Prescaler = cfg->prescaler; init.CounterMode = LL_TIM_COUNTERMODE_UP; init.Autoreload = counter_get_max_top_value(dev); init.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1; if (LL_TIM_Init(timer, &init) != SUCCESS) { LOG_ERR("Could not initialize timer"); return -EIO; } return 0; } static uint32_t counter_stm32_get_guard_period(const struct device *dev, uint32_t flags) { struct counter_stm32_data *data = dev->data; ARG_UNUSED(flags); return data->guard_period; } static int counter_stm32_set_guard_period(const struct device *dev, uint32_t guard, uint32_t flags) { struct counter_stm32_data *data = dev->data; ARG_UNUSED(flags); __ASSERT_NO_MSG(guard < counter_stm32_get_top_value(dev)); data->guard_period = guard; return 0; } static uint32_t counter_stm32_get_freq(const struct device *dev) { struct counter_stm32_data *data = dev->data; return data->freq; } static void counter_stm32_top_irq_handle(const struct device *dev) { struct counter_stm32_data *data = dev->data; counter_top_callback_t cb = data->top_cb; __ASSERT(cb != NULL, "top event enabled - expecting callback"); cb(dev, data->top_user_data); } static void counter_stm32_alarm_irq_handle(const struct device *dev, uint32_t id) { const struct counter_stm32_config *config = dev->config; struct counter_stm32_data *data = dev->data; TIM_TypeDef *timer = config->timer; struct counter_stm32_ch_data *chdata; counter_alarm_callback_t cb; atomic_and(&data->cc_int_pending, ~BIT(id)); disable_it[id](timer); chdata = &config->ch_data[id]; cb = chdata->callback; chdata->callback = NULL; if (cb) { uint32_t cc_val = get_timer_compare[id](timer); cb(dev, id, cc_val, chdata->user_data); } } static const struct counter_driver_api counter_stm32_driver_api = { .start = counter_stm32_start, .stop = counter_stm32_stop, .get_value = counter_stm32_get_value, .set_alarm = counter_stm32_set_alarm, .cancel_alarm = counter_stm32_cancel_alarm, .set_top_value = counter_stm32_set_top_value, .get_pending_int = counter_stm32_get_pending_int, .get_top_value = counter_stm32_get_top_value, .get_guard_period = counter_stm32_get_guard_period, .set_guard_period = counter_stm32_set_guard_period, .get_freq = counter_stm32_get_freq, }; #define TIM_IRQ_HANDLE_CC(timx, cc) \ do { \ bool hw_irq = LL_TIM_IsActiveFlag_CC##cc(timer) && \ LL_TIM_IsEnabledIT_CC##cc(timer); \ if (hw_irq || (data->cc_int_pending & BIT(cc - 1U))) { \ if (hw_irq) { \ LL_TIM_ClearFlag_CC##cc(timer); \ } \ counter_stm32_alarm_irq_handle(dev, cc - 1U); \ } \ } while (0) void counter_stm32_irq_handler(const struct device *dev) { const struct counter_stm32_config *config = dev->config; struct counter_stm32_data *data = dev->data; TIM_TypeDef *timer = config->timer; /* Capture compare events */ switch (counter_get_num_of_channels(dev)) { case 4U: TIM_IRQ_HANDLE_CC(timer, 4); __fallthrough; case 3U: TIM_IRQ_HANDLE_CC(timer, 3); __fallthrough; case 2U: TIM_IRQ_HANDLE_CC(timer, 2); __fallthrough; case 1U: TIM_IRQ_HANDLE_CC(timer, 1); } /* TIM Update event */ if (LL_TIM_IsActiveFlag_UPDATE(timer) && LL_TIM_IsEnabledIT_UPDATE(timer)) { LL_TIM_ClearFlag_UPDATE(timer); counter_stm32_top_irq_handle(dev); } } #define TIMER(idx) DT_INST_PARENT(idx) /** TIMx instance from DT */ #define TIM(idx) ((TIM_TypeDef *)DT_REG_ADDR(TIMER(idx))) #define COUNTER_DEVICE_INIT(idx) \ BUILD_ASSERT(DT_PROP(TIMER(idx), st_prescaler) <= 0xFFFF, \ "TIMER prescaler out of range"); \ BUILD_ASSERT(NUM_CH(TIM(idx)) <= TIMER_MAX_CH, \ "TIMER too many channels"); \ \ static struct counter_stm32_data counter##idx##_data; \ static struct counter_stm32_ch_data counter##idx##_ch_data[TIMER_MAX_CH]; \ \ static void counter_##idx##_stm32_irq_config(const struct device *dev) \ { \ IRQ_CONNECT(DT_IRQN(TIMER(idx)), \ DT_IRQ(TIMER(idx), priority), \ counter_stm32_irq_handler, \ DEVICE_DT_INST_GET(idx), \ 0); \ irq_enable(DT_IRQN(TIMER(idx))); \ } \ \ static const struct counter_stm32_config counter##idx##_config = { \ .info = { \ .max_top_value = \ IS_TIM_32B_COUNTER_INSTANCE(TIM(idx)) ? \ 0xFFFFFFFF : 0x0000FFFF, \ .flags = COUNTER_CONFIG_INFO_COUNT_UP, \ .channels = NUM_CH(TIM(idx)), \ }, \ .ch_data = counter##idx##_ch_data, \ .timer = TIM(idx), \ .prescaler = DT_PROP(TIMER(idx), st_prescaler), \ .pclken = { \ .bus = DT_CLOCKS_CELL(TIMER(idx), bus), \ .enr = DT_CLOCKS_CELL(TIMER(idx), bits) \ }, \ .irq_config_func = counter_##idx##_stm32_irq_config, \ .irqn = DT_IRQN(TIMER(idx)), \ .reset = RESET_DT_SPEC_GET(TIMER(idx)), \ }; \ \ DEVICE_DT_INST_DEFINE(idx, \ counter_stm32_init_timer, \ NULL, \ &counter##idx##_data, \ &counter##idx##_config, \ PRE_KERNEL_1, CONFIG_COUNTER_INIT_PRIORITY, \ &counter_stm32_driver_api); DT_INST_FOREACH_STATUS_OKAY(COUNTER_DEVICE_INIT)