/* * Copyright (c) 2018, Nordic Semiconductor ASA * * SPDX-License-Identifier: Apache-2.0 */ #include #include #include #include #include #ifdef DPPI_PRESENT #include #else #include #endif #define LOG_MODULE_NAME counter_rtc #include LOG_MODULE_REGISTER(LOG_MODULE_NAME, CONFIG_COUNTER_LOG_LEVEL); #define ERR(...) LOG_INST_ERR(get_nrfx_config(dev)->log, __VA_ARGS__) #define WRN(...) LOG_INST_WRN(get_nrfx_config(dev)->log, __VA_ARGS__) #define INF(...) LOG_INST_INF(get_nrfx_config(dev)->log, __VA_ARGS__) #define DBG(...) LOG_INST_DBG(get_nrfx_config(dev)->log, __VA_ARGS__) #define COUNTER_MAX_TOP_VALUE RTC_COUNTER_COUNTER_Msk #define COUNTER_GET_TOP_CH(dev) counter_get_num_of_channels(dev) #define IS_FIXED_TOP(dev) COND_CODE_1(CONFIG_COUNTER_RTC_CUSTOM_TOP_SUPPORT, \ (get_nrfx_config(dev)->fixed_top), (true)) #define IS_PPI_WRAP(dev) COND_CODE_1(CONFIG_COUNTER_RTC_WITH_PPI_WRAP, \ (get_nrfx_config(dev)->use_ppi), (false)) #define CC_ADJUSTED_OFFSET 16 #define CC_ADJ_MASK(chan) (BIT(chan + CC_ADJUSTED_OFFSET)) struct counter_nrfx_data { counter_top_callback_t top_cb; void *top_user_data; uint32_t top; uint32_t guard_period; /* Store channel interrupt pending and CC adjusted flags. */ atomic_t ipend_adj; #if CONFIG_COUNTER_RTC_WITH_PPI_WRAP uint8_t ppi_ch; #endif }; struct counter_nrfx_ch_data { counter_alarm_callback_t callback; void *user_data; }; struct counter_nrfx_config { struct counter_config_info info; struct counter_nrfx_ch_data *ch_data; NRF_RTC_Type *rtc; #if CONFIG_COUNTER_RTC_WITH_PPI_WRAP bool use_ppi; #endif #if CONFIG_COUNTER_RTC_CUSTOM_TOP_SUPPORT bool fixed_top; #endif LOG_INSTANCE_PTR_DECLARE(log); }; static inline struct counter_nrfx_data *get_dev_data(struct device *dev) { return dev->driver_data; } static inline const struct counter_nrfx_config *get_nrfx_config( struct device *dev) { return CONTAINER_OF(dev->config_info, struct counter_nrfx_config, info); } static int start(struct device *dev) { nrf_rtc_task_trigger(get_nrfx_config(dev)->rtc, NRF_RTC_TASK_START); return 0; } static int stop(struct device *dev) { nrf_rtc_task_trigger(get_nrfx_config(dev)->rtc, NRF_RTC_TASK_STOP); return 0; } static uint32_t read(struct device *dev) { return nrf_rtc_counter_get(get_nrfx_config(dev)->rtc); } static int get_value(struct device *dev, uint32_t *ticks) { *ticks = read(dev); return 0; } /* Return true if value equals 2^n - 1 */ static inline bool is_bit_mask(uint32_t val) { return !(val & (val + 1)); } /* Function calculates distance between to values assuming that one first * argument is in front and that values wrap. */ static uint32_t ticks_sub(struct device *dev, uint32_t val, uint32_t old, uint32_t top) { if (IS_FIXED_TOP(dev)) { return (val - old) & COUNTER_MAX_TOP_VALUE; } else if (likely(is_bit_mask(top))) { return (val - old) & top; } /* if top is not 2^n-1 */ return (val >= old) ? (val - old) : val + top + 1 - old; } static uint32_t skip_zero_on_custom_top(uint32_t val, uint32_t top) { /* From Product Specification: If a CC register value is 0 when * a CLEAR task is set, this will not trigger a COMPARE event. */ if (unlikely(val == 0) && (top != COUNTER_MAX_TOP_VALUE)) { val++; } return val; } static uint32_t ticks_add(struct device *dev, uint32_t val1, uint32_t val2, uint32_t top) { uint32_t sum = val1 + val2; if (IS_FIXED_TOP(dev)) { ARG_UNUSED(top); return sum & COUNTER_MAX_TOP_VALUE; } if (likely(is_bit_mask(top))) { sum = sum & top; } else { sum = sum > top ? sum - (top + 1) : sum; } return skip_zero_on_custom_top(sum, top); } static void set_cc_int_pending(struct device *dev, uint8_t chan) { atomic_or(&get_dev_data(dev)->ipend_adj, BIT(chan)); NRFX_IRQ_PENDING_SET(NRFX_IRQ_NUMBER_GET(get_nrfx_config(dev)->rtc)); } /** @brief Handle case when CC value equals COUNTER+1. * * RTC will not generate event if CC value equals COUNTER+1. If such CC is * about to be set then special algorithm is applied. Since counter must not * expire before expected value, CC is set to COUNTER+2. If COUNTER progressed * during that time it means that target value is reached and interrupt is * manually triggered. If not then interrupt is enabled since it is expected * that CC value will generate event. * * Additionally, an information about CC adjustment is stored. This information * is used in the callback to return original CC value which was requested by * the user. */ static void handle_next_tick_case(struct device *dev, uint8_t chan, uint32_t now, uint32_t val) { val = ticks_add(dev, val, 1, get_dev_data(dev)->top); nrf_rtc_cc_set(get_nrfx_config(dev)->rtc, chan, val); atomic_or(&get_dev_data(dev)->ipend_adj, CC_ADJ_MASK(chan)); if (nrf_rtc_counter_get(get_nrfx_config(dev)->rtc) != now) { set_cc_int_pending(dev, chan); } else { nrf_rtc_int_enable(get_nrfx_config(dev)->rtc, RTC_CHANNEL_INT_MASK(chan)); } } /* * @brief Set COMPARE value with optional too late setting detection. * * Setting CC algorithm takes into account: * - Current COMPARE value written to the register may be close to the current * COUNTER value thus COMPARE event may be generated at any moment * - Next COMPARE value may be soon in the future. Taking into account potential * preemption COMPARE value may be set too late. * - RTC registers are clocked with LF clock (32kHz) and sampled between two * LF ticks. * - Setting COMPARE register to COUNTER+1 does not generate COMPARE event if * done half tick before tick boundary. * * Algorithm assumes that: * - COMPARE interrupt is disabled * - absolute value is taking into account guard period. It means that * it won't be further in future than - from now. * * @param dev Device. * @param chan COMPARE channel. * @param val Value (absolute or relative). * @param flags Alarm flags. * * @retval 0 if COMPARE value was set on time and COMPARE interrupt is expected. * @retval -ETIME if absolute alarm was set too late and error reporting is * enabled. * */ static int set_cc(struct device *dev, uint8_t chan, uint32_t val, uint32_t flags) { __ASSERT_NO_MSG(get_dev_data(dev)->guard_period < get_dev_data(dev)->top); NRF_RTC_Type *rtc = get_nrfx_config(dev)->rtc; nrf_rtc_event_t evt; uint32_t prev_val; uint32_t top; uint32_t now; uint32_t diff; uint32_t int_mask = RTC_CHANNEL_INT_MASK(chan); int err = 0; uint32_t max_rel_val; bool absolute = flags & COUNTER_ALARM_CFG_ABSOLUTE; bool irq_on_late; __ASSERT(nrf_rtc_int_enable_check(rtc, int_mask) == 0, "Expected that CC interrupt is disabled."); evt = RTC_CHANNEL_EVENT_ADDR(chan); top = get_dev_data(dev)->top; now = nrf_rtc_counter_get(rtc); /* 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 furtherest * future). If CC was set to next tick we need to wait for up to 15us * (half of 32k tick) and clean potential event. After that time there * is no risk of unwanted event. */ prev_val = nrf_rtc_cc_get(rtc, chan); nrf_rtc_event_clear(rtc, evt); nrf_rtc_cc_set(rtc, chan, now); nrf_rtc_event_enable(rtc, int_mask); if (ticks_sub(dev, prev_val, now, top) == 1) { NRFX_DELAY_US(15); nrf_rtc_event_clear(rtc, evt); } now = nrf_rtc_counter_get(rtc); if (absolute) { val = skip_zero_on_custom_top(val, top); irq_on_late = flags & COUNTER_ALARM_CFG_EXPIRE_WHEN_LATE; max_rel_val = top - get_dev_data(dev)->guard_period; } 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 / 2); /* limit max to detect short relative being set too late. */ max_rel_val = irq_on_late ? top / 2 : top; val = ticks_add(dev, now, val, top); } diff = ticks_sub(dev, val, now, top); if (diff == 1) { /* CC cannot be set to COUNTER+1 because that will not * generate an event. In that case, special handling is * performed (attempt to set CC to COUNTER+2). */ handle_next_tick_case(dev, chan, now, val); } else { nrf_rtc_cc_set(rtc, chan, val); now = nrf_rtc_counter_get(rtc); /* decrement value to detect also case when val == read(dev). * Otherwise, condition would need to include comparing diff * against 0. */ diff = ticks_sub(dev, val - 1, now, 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) { set_cc_int_pending(dev, chan); } else { get_nrfx_config(dev)->ch_data[chan].callback = NULL; } } else if (diff == 0) { /* It is possible that setting CC was interrupted and * CC might be set to COUNTER+1 value which will not * generate an event. In that case, special handling * is performed (attempt to set CC to COUNTER+2). */ handle_next_tick_case(dev, chan, now, val); } else { nrf_rtc_int_enable(rtc, int_mask); } } return err; } static int set_channel_alarm(struct device *dev, uint8_t chan, const struct counter_alarm_cfg *alarm_cfg) { const struct counter_nrfx_config *nrfx_config = get_nrfx_config(dev); struct counter_nrfx_ch_data *chdata = &nrfx_config->ch_data[chan]; if (alarm_cfg->ticks > get_dev_data(dev)->top) { return -EINVAL; } if (chdata->callback) { return -EBUSY; } chdata->callback = alarm_cfg->callback; chdata->user_data = alarm_cfg->user_data; atomic_and(&get_dev_data(dev)->ipend_adj, ~CC_ADJ_MASK(chan)); return set_cc(dev, chan, alarm_cfg->ticks, alarm_cfg->flags); } static void disable(struct device *dev, uint8_t chan) { const struct counter_nrfx_config *config = get_nrfx_config(dev); NRF_RTC_Type *rtc = config->rtc; nrf_rtc_event_t evt = RTC_CHANNEL_EVENT_ADDR(chan); nrf_rtc_int_disable(rtc, RTC_CHANNEL_INT_MASK(chan)); nrf_rtc_event_disable(rtc, RTC_CHANNEL_INT_MASK(chan)); nrf_rtc_event_clear(rtc, evt); config->ch_data[chan].callback = NULL; } static int cancel_alarm(struct device *dev, uint8_t chan_id) { disable(dev, chan_id); return 0; } static int ppi_setup(struct device *dev, uint8_t chan) { #if CONFIG_COUNTER_RTC_WITH_PPI_WRAP const struct counter_nrfx_config *nrfx_config = get_nrfx_config(dev); struct counter_nrfx_data *data = get_dev_data(dev); NRF_RTC_Type *rtc = nrfx_config->rtc; nrf_rtc_event_t evt = RTC_CHANNEL_EVENT_ADDR(chan); nrfx_err_t result; if (!nrfx_config->use_ppi) { return 0; } nrf_rtc_event_enable(rtc, RTC_CHANNEL_INT_MASK(chan)); #ifdef DPPI_PRESENT result = nrfx_dppi_channel_alloc(&data->ppi_ch); if (result != NRFX_SUCCESS) { ERR("Failed to allocate PPI channel."); return -ENODEV; } nrf_rtc_subscribe_set(rtc, NRF_RTC_TASK_CLEAR, data->ppi_ch); nrf_rtc_publish_set(rtc->p_reg, evt, data->ppi_ch); (void)nrfx_dppi_channel_enable(data->ppi_ch); #else /* DPPI_PRESENT */ uint32_t evt_addr; uint32_t task_addr; evt_addr = nrf_rtc_event_address_get(rtc, evt); task_addr = nrf_rtc_task_address_get(rtc, NRF_RTC_TASK_CLEAR); result = nrfx_ppi_channel_alloc(&data->ppi_ch); if (result != NRFX_SUCCESS) { ERR("Failed to allocate PPI channel."); return -ENODEV; } (void)nrfx_ppi_channel_assign(data->ppi_ch, evt_addr, task_addr); (void)nrfx_ppi_channel_enable(data->ppi_ch); #endif #endif /* CONFIG_COUNTER_RTC_WITH_PPI_WRAP */ return 0; } static void ppi_free(struct device *dev, uint8_t chan) { #if CONFIG_COUNTER_RTC_WITH_PPI_WRAP const struct counter_nrfx_config *nrfx_config = get_nrfx_config(dev); uint8_t ppi_ch = get_dev_data(dev)->ppi_ch; NRF_RTC_Type *rtc = nrfx_config->rtc; if (!nrfx_config->use_ppi) { return; } nrf_rtc_event_disable(rtc, RTC_CHANNEL_INT_MASK(chan)); #ifdef DPPI_PRESENT NRF_RTC_Type *rtc = nrfx_config->rtc; nrf_rtc_event_t evt = RTC_CHANNEL_EVENT_ADDR(chan); (void)nrfx_dppi_channel_disable(ppi_ch); nrf_rtc_subscribe_clear(rtc, NRF_RTC_TASK_CLEAR); nrf_rtc_publish_clear(rtc, evt); (void)nrfx_dppi_channel_free(ppi_ch); #else /* DPPI_PRESENT */ (void)nrfx_ppi_channel_disable(ppi_ch); (void)nrfx_ppi_channel_free(ppi_ch); #endif #endif } /* Return true if counter must be cleared by the CPU. It is cleared * automatically in case of max top value or PPI usage. */ static bool sw_wrap_required(struct device *dev) { return (get_dev_data(dev)->top != COUNTER_MAX_TOP_VALUE) && !IS_PPI_WRAP(dev); } static int set_fixed_top_value(struct device *dev, const struct counter_top_cfg *cfg) { NRF_RTC_Type *rtc = get_nrfx_config(dev)->rtc; if (cfg->ticks != COUNTER_MAX_TOP_VALUE) { return -EINVAL; } nrf_rtc_int_disable(rtc, NRF_RTC_INT_OVERFLOW_MASK); get_dev_data(dev)->top_cb = cfg->callback; get_dev_data(dev)->top_user_data = cfg->user_data; if (!(cfg->flags & COUNTER_TOP_CFG_DONT_RESET)) { nrf_rtc_task_trigger(rtc, NRF_RTC_TASK_CLEAR); } if (cfg->callback) { nrf_rtc_int_enable(rtc, NRF_RTC_INT_OVERFLOW_MASK); } return 0; } static int set_top_value(struct device *dev, const struct counter_top_cfg *cfg) { const struct counter_nrfx_config *nrfx_config = get_nrfx_config(dev); NRF_RTC_Type *rtc = nrfx_config->rtc; struct counter_nrfx_data *dev_data = get_dev_data(dev); uint32_t top_ch = COUNTER_GET_TOP_CH(dev); int err = 0; if (IS_FIXED_TOP(dev)) { return set_fixed_top_value(dev, cfg); } for (int i = 0; i < counter_get_num_of_channels(dev); i++) { /* Overflow can be changed only when all alarms are * disables. */ if (nrfx_config->ch_data[i].callback) { return -EBUSY; } } nrf_rtc_int_disable(rtc, RTC_CHANNEL_INT_MASK(top_ch)); if (IS_PPI_WRAP(dev)) { if ((dev_data->top == COUNTER_MAX_TOP_VALUE) && cfg->ticks != COUNTER_MAX_TOP_VALUE) { err = ppi_setup(dev, top_ch); } else if (((dev_data->top != COUNTER_MAX_TOP_VALUE) && cfg->ticks == COUNTER_MAX_TOP_VALUE)) { ppi_free(dev, top_ch); } } dev_data->top_cb = cfg->callback; dev_data->top_user_data = cfg->user_data; dev_data->top = cfg->ticks; nrf_rtc_cc_set(rtc, top_ch, cfg->ticks); if (!(cfg->flags & COUNTER_TOP_CFG_DONT_RESET)) { nrf_rtc_task_trigger(rtc, NRF_RTC_TASK_CLEAR); } else if (read(dev) >= cfg->ticks) { err = -ETIME; if (cfg->flags & COUNTER_TOP_CFG_RESET_WHEN_LATE) { nrf_rtc_task_trigger(rtc, NRF_RTC_TASK_CLEAR); } } if (cfg->callback || sw_wrap_required(dev)) { nrf_rtc_int_enable(rtc, RTC_CHANNEL_INT_MASK(top_ch)); } return err; } static uint32_t get_pending_int(struct device *dev) { return 0; } static int init_rtc(struct device *dev, uint32_t prescaler) { const struct counter_nrfx_config *nrfx_config = get_nrfx_config(dev); struct counter_top_cfg top_cfg = { .ticks = COUNTER_MAX_TOP_VALUE }; NRF_RTC_Type *rtc = nrfx_config->rtc; int err; z_nrf_clock_control_lf_on(NRF_LFCLK_START_MODE_NOWAIT); nrf_rtc_prescaler_set(rtc, prescaler); NRFX_IRQ_ENABLE(NRFX_IRQ_NUMBER_GET(rtc)); get_dev_data(dev)->top = COUNTER_MAX_TOP_VALUE; err = set_top_value(dev, &top_cfg); DBG("Initialized"); return err; } static uint32_t get_top_value(struct device *dev) { return get_dev_data(dev)->top; } static uint32_t get_max_relative_alarm(struct device *dev) { return get_dev_data(dev)->top; } static uint32_t get_guard_period(struct device *dev, uint32_t flags) { return get_dev_data(dev)->guard_period; } static int set_guard_period(struct device *dev, uint32_t guard, uint32_t flags) { get_dev_data(dev)->guard_period = guard; return 0; } static void top_irq_handle(struct device *dev) { NRF_RTC_Type *rtc = get_nrfx_config(dev)->rtc; counter_top_callback_t cb = get_dev_data(dev)->top_cb; nrf_rtc_event_t top_evt; top_evt = IS_FIXED_TOP(dev) ? NRF_RTC_EVENT_OVERFLOW : RTC_CHANNEL_EVENT_ADDR(counter_get_num_of_channels(dev)); if (nrf_rtc_event_check(rtc, top_evt)) { nrf_rtc_event_clear(rtc, top_evt); /* Perform manual clear if custom top value is used and PPI * clearing is not used. */ if (!IS_FIXED_TOP(dev) && !IS_PPI_WRAP(dev)) { nrf_rtc_task_trigger(rtc, NRF_RTC_TASK_CLEAR); } if (cb) { cb(dev, get_dev_data(dev)->top_user_data); } } } static void alarm_irq_handle(struct device *dev, uint32_t chan) { NRF_RTC_Type *rtc = get_nrfx_config(dev)->rtc; nrf_rtc_event_t evt = RTC_CHANNEL_EVENT_ADDR(chan); uint32_t int_mask = RTC_CHANNEL_INT_MASK(chan); bool hw_irq_pending = nrf_rtc_event_check(rtc, evt) && nrf_rtc_int_enable_check(rtc, int_mask); bool sw_irq_pending = get_dev_data(dev)->ipend_adj & BIT(chan); if (hw_irq_pending || sw_irq_pending) { struct counter_nrfx_ch_data *chdata; counter_alarm_callback_t cb; nrf_rtc_event_clear(rtc, evt); atomic_and(&get_dev_data(dev)->ipend_adj, ~BIT(chan)); nrf_rtc_int_disable(rtc, int_mask); chdata = &get_nrfx_config(dev)->ch_data[chan]; cb = chdata->callback; chdata->callback = NULL; if (cb) { uint32_t cc = nrf_rtc_cc_get(rtc, chan); if (get_dev_data(dev)->ipend_adj & CC_ADJ_MASK(chan)) { cc = ticks_sub(dev, cc, 1, get_dev_data(dev)->top); } cb(dev, chan, cc, chdata->user_data); } } } static void irq_handler(struct device *dev) { top_irq_handle(dev); for (uint32_t i = 0; i < counter_get_num_of_channels(dev); i++) { alarm_irq_handle(dev, i); } } static const struct counter_driver_api counter_nrfx_driver_api = { .start = start, .stop = stop, .get_value = get_value, .set_alarm = set_channel_alarm, .cancel_alarm = cancel_alarm, .set_top_value = set_top_value, .get_pending_int = get_pending_int, .get_top_value = get_top_value, .get_max_relative_alarm = get_max_relative_alarm, .get_guard_period = get_guard_period, .set_guard_period = set_guard_period, }; /* * Devicetree access is done with node labels due to HAL API * requirements. In particular, RTCx_CC_NUM values from HALs * are indexed by peripheral number, so DT_INST APIs won't work. */ #define RTC(idx) DT_NODELABEL(rtc##idx) #define RTC_PROP(idx, prop) DT_PROP(RTC(idx), prop) #define COUNTER_NRF_RTC_DEVICE(idx) \ BUILD_ASSERT((RTC_PROP(idx, prescaler) - 1) <= \ RTC_PRESCALER_PRESCALER_Msk, \ "RTC prescaler out of range"); \ DEVICE_DECLARE(rtc_##idx); \ static int counter_##idx##_init(struct device *dev) \ { \ IRQ_CONNECT(DT_IRQN(RTC(idx)), DT_IRQ(RTC(idx), priority), \ irq_handler, DEVICE_GET(rtc_##idx), 0); \ return init_rtc(dev, RTC_PROP(idx, prescaler) - 1); \ } \ static struct counter_nrfx_data counter_##idx##_data; \ static struct counter_nrfx_ch_data \ counter##idx##_ch_data[RTC##idx##_CC_NUM]; \ LOG_INSTANCE_REGISTER(LOG_MODULE_NAME, idx, CONFIG_COUNTER_LOG_LEVEL); \ static const struct counter_nrfx_config nrfx_counter_##idx##_config = {\ .info = { \ .max_top_value = COUNTER_MAX_TOP_VALUE, \ .freq = RTC_PROP(idx, clock_frequency) / \ RTC_PROP(idx, prescaler), \ .flags = COUNTER_CONFIG_INFO_COUNT_UP, \ .channels = RTC_PROP(idx, fixed_top) ? \ RTC##idx##_CC_NUM : RTC##idx##_CC_NUM - 1 \ }, \ .ch_data = counter##idx##_ch_data, \ .rtc = (NRF_RTC_Type *)DT_REG_ADDR(RTC(idx)), \ IF_ENABLED(CONFIG_COUNTER_RTC_WITH_PPI_WRAP, \ (.use_ppi = RTC_PROP(idx, ppi_wrap),)) \ IF_ENABLED(CONFIG_COUNTER_RTC_CUSTOM_TOP_SUPPORT, \ (.fixed_top = RTC_PROP(idx, fixed_top),)) \ LOG_INSTANCE_PTR_INIT(log, LOG_MODULE_NAME, idx) \ }; \ DEVICE_AND_API_INIT(rtc_##idx, \ DT_LABEL(RTC(idx)), \ counter_##idx##_init, \ &counter_##idx##_data, \ &nrfx_counter_##idx##_config.info, \ PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \ &counter_nrfx_driver_api) #ifdef CONFIG_COUNTER_RTC0 COUNTER_NRF_RTC_DEVICE(0); #endif #ifdef CONFIG_COUNTER_RTC1 COUNTER_NRF_RTC_DEVICE(1); #endif #ifdef CONFIG_COUNTER_RTC2 COUNTER_NRF_RTC_DEVICE(2); #endif