gustavonihei commented on a change in pull request #4401: URL: https://github.com/apache/incubator-nuttx/pull/4401#discussion_r698767670
########## File path: arch/xtensa/src/esp32s2/esp32s2_tim_lowerhalf.c ########## @@ -0,0 +1,595 @@ +/**************************************************************************** + * arch/xtensa/src/esp32s2/esp32s2_tim_lowerhalf.c + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. The + * ASF licenses this file to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance with the + * License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + * License for the specific language governing permissions and limitations + * under the License. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <stdbool.h> +#include <string.h> +#include <assert.h> +#include <errno.h> +#include <debug.h> +#include <stdio.h> +#include <stdint.h> + +#include <nuttx/arch.h> +#include <nuttx/timers/timer.h> + +#include "hardware/esp32s2_soc.h" + +#include "esp32s2_tim.h" +#include "esp32s2_clockconfig.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +struct esp32s2_timer_lowerhalf_s +{ + FAR const struct timer_ops_s *ops; /* Lower half operations */ + FAR struct esp32s2_tim_dev_s *tim; /* esp32s2 timer driver */ + tccb_t callback; /* Interrupt callback */ + FAR void *arg; /* Argument passed to upper half callback */ + bool started; /* True: Timer has been started */ + void *upper; /* Pointer to watchdog_upperhalf_s */ +}; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +static int esp32s2_timer_handler(int irq, void *context, void *arg); + +/* "Lower half" driver methods **********************************************/ + +static int esp32s2_timer_start(FAR struct timer_lowerhalf_s *lower); +static int esp32s2_timer_stop(FAR struct timer_lowerhalf_s *lower); +static int esp32s2_timer_getstatus(FAR struct timer_lowerhalf_s *lower, + FAR struct timer_status_s *status); +static int esp32s2_timer_settimeout(FAR struct timer_lowerhalf_s *lower, + uint32_t timeout); +static int esp32s2_timer_maxtimeout(FAR struct timer_lowerhalf_s *lower, + uint32_t *timeout); +static void esp32s2_timer_setcallback(FAR struct timer_lowerhalf_s *lower, + tccb_t callback, FAR void *arg); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/* "Lower half" driver methods */ + +static const struct timer_ops_s g_esp32s2_timer_ops = +{ + .start = esp32s2_timer_start, + .stop = esp32s2_timer_stop, + .getstatus = esp32s2_timer_getstatus, + .settimeout = esp32s2_timer_settimeout, + .setcallback = esp32s2_timer_setcallback, + .maxtimeout = esp32s2_timer_maxtimeout, + .ioctl = NULL, +}; + +#ifdef CONFIG_ESP32S2_TIMER0 + +/* TIMER0 lower-half */ + +static struct esp32s2_timer_lowerhalf_s g_esp32s2_timer0_lowerhalf = +{ + .ops = &g_esp32s2_timer_ops, +}; +#endif + +#ifdef CONFIG_ESP32S2_TIMER1 + +/* TIMER1 lower-half */ + +static struct esp32s2_timer_lowerhalf_s g_esp32s2_timer1_lowerhalf = +{ + .ops = &g_esp32s2_timer_ops, +}; +#endif + +#ifdef CONFIG_ESP32S2_TIMER2 + +/* TIMER2 lower-half */ + +static struct esp32s2_timer_lowerhalf_s g_esp32s2_timer2_lowerhalf = +{ + .ops = &g_esp32s2_timer_ops, +}; +#endif + +#ifdef CONFIG_ESP32S2_TIMER3 + +/* TIMER3 lower-half */ + +static struct esp32s2_timer_lowerhalf_s g_esp32s2_timer3_lowerhalf = +{ + .ops = &g_esp32s2_timer_ops, +}; +#endif + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: esp32s2_timer_handler + * + * Description: + * Timer interrupt handler + * + ****************************************************************************/ + +static int esp32s2_timer_handler(int irq, void *context, void *arg) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)arg; + uint32_t next_interval_us = 0; + + if (priv->callback(&next_interval_us, priv->upper)) + { + if (next_interval_us > 0) + { + /* Set a value to the alarm */ + + ESP32S2_TIM_SETALRVL(priv->tim, next_interval_us); + } + } + else + { + esp32s2_timer_stop((struct timer_lowerhalf_s *)priv); + } + + ESP32S2_TIM_SETALRM(priv->tim, true); /* Re-enables the alarm */ + ESP32S2_TIM_ACKINT(priv->tim); /* Clear the Interrupt */ + return OK; +} + +/**************************************************************************** + * Name: esp32s2_timer_start + * + * Description: + * Start the timer, resetting the time to the current timeout + * + * Input Parameters: + * lower - A pointer to the representation of + * the "lower-half" driver state structure. + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +static int esp32s2_timer_start(FAR struct timer_lowerhalf_s *lower) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)lower; + int ret = OK; + uint16_t pre; + irqstate_t flags; + + DEBUGASSERT(priv); + + if (priv->started == true) + { + /* Return EBUSY to indicate that the timer is already running */ + + ret = -EBUSY; + goto errout; + } + + /* Make sure the timer is stopped to avoid unpredictable behavior */ + + ESP32S2_TIM_STOP(priv->tim); + + /* Configure clock source */ + + ESP32S2_TIM_CLK_SRC(priv->tim, ESP32S2_TIM_APB_CLK); + + /* Calculate the suitable prescaler according to the current APB + * frequency to generate a period of 1 us. + */ + + pre = esp_clk_apb_freq() / 1000000; + + /* Configure TIMER prescaler */ + + ESP32S2_TIM_SETPRE(priv->tim, pre); + + /* Configure TIMER mode */ + + ESP32S2_TIM_SETMODE(priv->tim, ESP32S2_TIM_MODE_UP); + + /* Clear TIMER counter value */ + + ESP32S2_TIM_CLEAR(priv->tim); + + /* Enable autoreload */ + + ESP32S2_TIM_SETARLD(priv->tim, true); + + /* Enable TIMER alarm */ + + ESP32S2_TIM_SETALRM(priv->tim, true); + + /* Clear Interrupt Bits Status */ + + ESP32S2_TIM_ACKINT(priv->tim); + + /* Configure callback, in case a handler was provided before */ + + if (priv->callback != NULL) + { + flags = enter_critical_section(); + ret = ESP32S2_TIM_SETISR(priv->tim, esp32s2_timer_handler, priv); + leave_critical_section(flags); + if (ret != OK) + { + goto errout; + } + + ESP32S2_TIM_ENABLEINT(priv->tim); + } + + /* Finally, start the TIMER */ + + ESP32S2_TIM_START(priv->tim); + priv->started = true; + +errout: + return ret; +} + +/**************************************************************************** + * Name: esp32s2_timer_stop + * + * Description: + * Stop the timer + * + * Input Parameters: + * lower - A pointer the publicly visible representation of + * the "lower-half" driver state structure. + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +static int esp32s2_timer_stop(FAR struct timer_lowerhalf_s *lower) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)lower; + int ret = OK; + irqstate_t flags; + + DEBUGASSERT(priv); + + if (priv->started == false) + { + /* Return ENODEV to indicate that the timer was not running */ + + ret = -ENODEV; + goto errout; + } + + if (priv->callback != NULL) + { + flags = enter_critical_section(); + ESP32S2_TIM_DISABLEINT(priv->tim); + ret = ESP32S2_TIM_SETISR(priv->tim, NULL, NULL); + leave_critical_section(flags); + priv->callback = NULL; + } + + ESP32S2_TIM_STOP(priv->tim); + priv->started = false; + +errout: + return ret; +} + +/**************************************************************************** + * Name: esp32s2_timer_getstatus + * + * Description: + * Get timer status. + * + * Input Parameters: + * lower - A pointer the publicly visible representation of the "lower- + * half" driver state structure. + * status - The location to return the status information. + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +static int esp32s2_timer_getstatus(FAR struct timer_lowerhalf_s *lower, + FAR struct timer_status_s *status) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)lower; + int ret = OK; + uint64_t current_counter_value; + uint64_t alarm_value; + + DEBUGASSERT(priv); + DEBUGASSERT(status); + + /* Return the status bit */ + + status->flags = 0; + + if (priv->started == true) + { + /* TIMER is running */ + + status->flags |= TCFLAGS_ACTIVE; + } + + if (priv->callback != NULL) + { + /* TIMER has a user callback function to be called when + * expiration happens + */ + + status->flags |= TCFLAGS_HANDLER; + } + + /* Get the current counter value */ + + ESP32S2_TIM_GETCTR(priv->tim, ¤t_counter_value); + + /* Get the current configured timeout */ + + ESP32S2_TIM_GETALRVL(priv->tim, &alarm_value); + + status->timeout = (uint32_t)(alarm_value); + status->timeleft = (uint32_t)(alarm_value - current_counter_value); + + return ret; +} + +/**************************************************************************** + * Name: esp32s2_timer_settimeout + * + * Description: + * Set a new timeout value. + * + * Input Parameters: + * lower - A pointer the publicly visible representation of + * the "lower-half" driver state structure. + * timeout - The new timeout value in microseconds. + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +static int esp32s2_timer_settimeout(FAR struct timer_lowerhalf_s *lower, + uint32_t timeout) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)lower; + int ret = OK; + + DEBUGASSERT(priv); + + /* Set the timeout */ + + ESP32S2_TIM_SETALRVL(priv->tim, (uint64_t)timeout); + + return ret; +} + +/**************************************************************************** + * Name: esp32s2_timer_maxtimeout + * + * Description: + * Get the maximum timeout value + * + * Input Parameters: + * lower - A pointer the publicly visible representation of + * the "lower-half" driver state structure. + * maxtimeout - A pointer to the variable that will store the max timeout. + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +static int esp32s2_timer_maxtimeout(FAR struct timer_lowerhalf_s *lower, + uint32_t *max_timeout) +{ + DEBUGASSERT(max_timeout); + + *max_timeout = UINT32_MAX; + + return OK; +} + +/**************************************************************************** + * Name: esp32s2_setcallback + * + * Description: + * Set the provided callback to be called at timeout from withing the + * ISR. + * + * Input Parameters: + * lower - A pointer to the publicly visible representation of + * the "lower-half" driver state structure. + * callback - A pointer to the callback. If this function pointer + * is NULL, then the reset-on-expiration behavior is restored. + * arg - A pointer to the argument that will be provided to + * the callback + * + ****************************************************************************/ + +static void esp32s2_timer_setcallback(FAR struct timer_lowerhalf_s *lower, + tccb_t callback, FAR void *arg) +{ + FAR struct esp32s2_timer_lowerhalf_s *priv = + (FAR struct esp32s2_timer_lowerhalf_s *)lower; + irqstate_t flags; + int ret = OK; + + DEBUGASSERT(priv); + + /* Save the new callback */ + + priv->callback = callback; + priv->arg = arg; + + flags = enter_critical_section(); + + /* There is a user callback and the timer has already been started */ + + if (callback != NULL && priv->started == true) + { + ret = ESP32S2_TIM_SETISR(priv->tim, esp32s2_timer_handler, priv); + ESP32S2_TIM_ENABLEINT(priv->tim); + } + else + { + ESP32S2_TIM_DISABLEINT(priv->tim); + ret = ESP32S2_TIM_SETISR(priv->tim, NULL, NULL); + } + + leave_critical_section(flags); + if (ret != OK) + { + tmrerr("Error to set ISR: %d", ret); + } +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: esp32s2_timer_initialize + * + * Description: + * Bind the configuration timer to a timer lower half instance and + * register the timer drivers at 'devpath' + * + * Input Parameters: + * devpath - The full path to the timer device. This should be of the + * form /dev/timerx. + * timer - the timer's number. + * + * Returned Value: + * Zero (OK) is returned on success; A negated errno value is returned + * to indicate the nature of any failure. + * + ****************************************************************************/ + +int esp32s2_timer_initialize(FAR const char *devpath, uint8_t timer) +{ + struct esp32s2_timer_lowerhalf_s *lower = NULL; + int ret = OK; + + DEBUGASSERT(devpath); + + switch (timer) + { +#ifdef CONFIG_ESP32S2_TIMER0 + case 0: Review comment: If those `TIMERx` defines are kept on the Timer interface, they could be used here for indexing the available timers. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
