xtensa/esp32: Adds oneshot timer driver.

arch/xtensa/src/esp32/Kconfig

@@ -957,6 +957,19 @@ config ESP32_RT_TIMER_TASK_STACK_SIZE
 
 endmenu # Real-Time Timer
 
+if ESP32_TIMER
+menu "Timer/counter Configuration"
+
+config ESP32_ONESHOT
+	bool "One-shot wrapper"
+	default n
+	---help---
+		Enable a wrapper around the low level timer/counter functions to
+		support one-shot timer.
+
+endmenu # Timer/counter Configuration
+endif # ESP32_TIMER
+
 menu "Partition Configuration"
 	depends on ESP32_PARTITION
 

arch/xtensa/src/esp32/Make.defs

@@ -153,6 +153,13 @@ CHIP_CSRCS += esp32_tim_lowerhalf.c
 endif
 endif
 
+ifeq ($(CONFIG_ESP32_ONESHOT),y)
+CHIP_CSRCS += esp32_oneshot.c
+ifeq ($(CONFIG_ONESHOT),y)
+CHIP_CSRCS += esp32_oneshot_lowerhalf.c
+endif
+endif
+
 ifeq ($(CONFIG_ESP32_PARTITION),y)
 CHIP_CSRCS += esp32_partition.c
 endif

arch/xtensa/src/esp32/esp32_oneshot.c

@@ -0,0 +1,449 @@
+/****************************************************************************
+ * arch/xtensa/src/esp32/esp32_oneshot.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 <errno.h>
+#include <debug.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/timers/oneshot.h>
+#include <nuttx/clock.h>
+
+#include "hardware/esp32_soc.h"
+
+#include "esp32_tim.h"
+#include "esp32_clockconfig.h"
+#include "esp32_oneshot.h"
+
+#ifdef CONFIG_ESP32_ONESHOT
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define MAX_TIMER_COUNTER UINT64_MAX
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static int esp32_oneshot_handler(int irq, void * context, void *arg);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_oneshot_handler
+ *
+ * Description:
+ *   Oneshot interrupt Handler. When any oneshot timer interrupt
+ *   expires, this function will be triggered. It will forward the call to
+ *   the next level up.
+ *
+ * Input Parameters:
+ *   irq   - IRQ associated to that interrupt
+ *   arg -   A pointer to the argument provided when the interrupt was
+ *           registered.
+ *
+ * Returned Value:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int esp32_oneshot_handler(int irq, void * context, void *arg)
+{
+  int ret = OK;
+  struct esp32_oneshot_s *oneshot = (struct esp32_oneshot_s *)arg;
+
+  DEBUGASSERT(oneshot != NULL && oneshot->handler != NULL);
+
+  tmrinfo("Oneshot handler triggered\n");
+
+  /* Stop timer
+   * Note: It's not necessary to disable the alarm because
+   * it automatically disables each time it expires.
+   */
+
+  ESP32_TIM_STOP(oneshot->tim);
+
+  /* Disable int */
+
+  ESP32_TIM_DISABLEINT(oneshot->tim);
+
+  /* Detach handler */
+
+  ret = ESP32_TIM_SETISR(oneshot->tim, NULL, NULL);
+
+  /* Call the callback */
+
+  oneshot->handler((void *)oneshot->arg);
+
+  /* Restore state */
+
+  oneshot->running = false;
+  oneshot->handler = NULL;
+  oneshot->arg = NULL;
+
+  /* Clear the Interrupt */
+
+  ESP32_TIM_ACKINT(oneshot->tim);
+
+  return ret;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_oneshot_initialize
+ *
+ * Description:
+ *   Initialize the oneshot timer wrapper.
+ *
+ * Input Parameters:
+ *   oneshot    Caller allocated instance of the oneshot state structure.
+ *   chan       Timer counter channel to be used.
+ *   resolution The required resolution of the timer in units of
+ *              microseconds.  NOTE that the range is restricted to the
+ *              range of uint16_t (excluding zero).
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_initialize(struct esp32_oneshot_s *oneshot, int chan,
+                             uint16_t resolution)
+{
+  uint16_t pre;
+  int ret = OK;
+  tmrinfo("chan=%d resolution=%d usecs\n", chan, resolution);
+  DEBUGASSERT(oneshot != NULL);
+  DEBUGASSERT(resolution > 0);
+
+  oneshot->chan = chan;
+
+  oneshot->tim = esp32_tim_init(chan);
+  if (oneshot->tim == NULL)
+    {
+      tmrerr("ERROR: Failed to allocate TIM %d\n", chan);
+      ret = -EBUSY;
+    }
+  else
+    {
+      /* Initialize the remaining fields in the state structure. */
+
+      oneshot->running    = false;
+      oneshot->handler    = NULL;
+      oneshot->arg        = NULL;
+      oneshot->resolution = resolution;
+
+      /* Ensure timer is disabled.
+       * Change the prescaler divider with the timer enabled can lead to
+       * unpredictable results.
+       */
+
+      ESP32_TIM_STOP(oneshot->tim);
+
+      /* Calculate the suitable prescaler according to the current apb
+       * frequency to generate a period equals to resolution.
+       */
+
+      pre = (esp_clk_apb_freq() * resolution) / USEC_PER_SEC;
+
+      /* Configure TIMER prescaler */
+
+      ESP32_TIM_SETPRE(oneshot->tim, pre);
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: esp32_oneshot_max_delay
+ *
+ * Input Parameters:
+ *   oneshot Caller allocated instance of the oneshot state structure. This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   usec    The maximum delay in us.
+ *
+ * Returned Value:
+ *   Zero (OK).
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_max_delay(struct esp32_oneshot_s *oneshot, uint64_t *usec)
+{
+  DEBUGASSERT(oneshot != NULL && usec != NULL);
+
+  /* In theory, Maximum delay (us) = resolution (us) * MAX_TIMER_COUNTER
+   * But if the resolution is bigger than 1 us, the value will not fit
+   * in a uint64_t. So, this function assumes the max delay using a
+   *  resolution of 1 us.
+   */
+
+  *usec = MAX_TIMER_COUNTER;
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: esp32_oneshot_start
+ *
+ * Description:
+ *   Start the oneshot timer
+ *
+ * Input Parameters:
+ *   oneshot Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   handler The function to call when when the oneshot timer expires.
+ *   arg     An opaque argument that will accompany the callback.
+ *   ts      Provides the duration of the one shot timer.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_start(struct esp32_oneshot_s *oneshot,
+                        oneshot_handler_t handler, void *arg,
+                        const struct timespec *ts)
+{
+  uint64_t timeout_us;
+  int ret = OK;
+
+  tmrinfo("handler=%p arg=%p, ts=(%lu, %lu)\n",
+          handler, arg, (unsigned long)ts->tv_sec,
+          (unsigned long)ts->tv_nsec);
+  DEBUGASSERT(oneshot != NULL);
+  DEBUGASSERT(handler != NULL);
+  DEBUGASSERT(ts != NULL);
+
+  if (oneshot->running)
+    {
+      tmrinfo("One shot timer already in use. Cancelling it ...\n");
+
+      /* If the oneshot timer was already started, cancel it and then
+       * restart.
+       */
+
+      esp32_oneshot_cancel(oneshot, NULL);
+    }
+
+  /* Save the new callback and its argument */
+
+  oneshot->handler = handler;
+  oneshot->arg     = arg;
+
+  /* Retrieve the duration from timespec in microsecond */
+
+  timeout_us = (uint64_t)ts->tv_sec * USEC_PER_SEC +
+               (uint64_t)(ts->tv_nsec / NSEC_PER_USEC);
+
+  /* Verify if it is a multiple of the configured resolution.
+   * In case it isn't, warn the user.
+   */
+
+  if ((timeout_us % oneshot->resolution) != 0)
+    {
+      tmrwarn("Warning: The interval is not multiple of the resolution.\n"
+               "Adjust the resolution in your bringup file.\n");
+    }
+
+  /* Set the timer */
+
+  /* Ensure timer is stopped */
+
+  ESP32_TIM_STOP(oneshot->tim);
+
+  /* Configure TIMER mode */
+
+  ESP32_TIM_SETMODE(oneshot->tim, ESP32_TIM_MODE_UP);
+
+  /* Clear TIMER counter value */
+
+  ESP32_TIM_CLEAR(oneshot->tim);
+
+  /* Disable autoreload */
+
+  ESP32_TIM_SETARLD(oneshot->tim, false);
+
+  /* Set the timeout */
+
+  ESP32_TIM_SETALRVL(oneshot->tim, timeout_us / oneshot->resolution);
+
+  /* Enable TIMER alarm */
+
+  ESP32_TIM_SETALRM(oneshot->tim, true);
+
+  /* Clear Interrupt Bits Status */
+
+  ESP32_TIM_ACKINT(oneshot->tim);
+
+  /* Set the interrupt */
+
+  /* Register the handler that calls the callback */
+
+  ret = ESP32_TIM_SETISR(oneshot->tim, esp32_oneshot_handler, oneshot);
+  if (ret == OK)
+    {
+      ESP32_TIM_ENABLEINT(oneshot->tim);
+
+      /* Finally, start the TIMER */
+
+      ESP32_TIM_START(oneshot->tim);
+
+      oneshot->running = true;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: esp32_oneshot_cancel
+ *
+ * Description:
+ *   Cancel the oneshot timer and return the time remaining on the timer.
+ *
+ *
+ * Input Parameters:
+ *   oneshot Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   ts      The location in which to return the time remaining on the
+ *           oneshot timer.  A time of zero is returned if the timer is
+ *           not running.  ts may be zero in which case the time remaining
+ *           is not returned.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  A call to up_timer_cancel() when
+ *   the timer is not active should also return success; a negated errno
+ *   value is returned on any failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_cancel(struct esp32_oneshot_s *oneshot,
+                         struct timespec *ts)
+{
+  int ret = OK;
+  uint64_t current_us;
+  uint64_t remaining_us;
+  uint64_t timeout_us;
+  uint64_t counter_value;
+  uint64_t alarm_value;
+
+  DEBUGASSERT(oneshot);
+
+  if (oneshot->running == false)
+    {
+      tmrinfo("Trying to cancel a non started oneshot timer.\n");
+      ts->tv_sec  = 0;
+      ts->tv_nsec = 0;
+    }
+  else
+    {
+      /* Stop timer */
+
+      ESP32_TIM_STOP(oneshot->tim);
+
+      /* Disable int */
+
+      ESP32_TIM_DISABLEINT(oneshot->tim);
+
+      /* Detach handler */
+
+      ret = ESP32_TIM_SETISR(oneshot->tim, NULL, NULL);
+
+      if (ts != NULL)
+        {
+          /* Get the current counter value */
+
+          ESP32_TIM_GETCTR(oneshot->tim, &counter_value);
+
+          /* Get the current configured timeout */
+
+          ESP32_TIM_GETALRVL(oneshot->tim, &alarm_value);
+
+          current_us = counter_value * oneshot->resolution;
+          timeout_us = alarm_value   * oneshot->resolution;
+
+          /* Remaining time (us) = timeout (us) - current (us) */
+
+          remaining_us = timeout_us - current_us;
+          ts->tv_sec   = remaining_us / USEC_PER_SEC;
+          remaining_us = remaining_us - ts->tv_sec * USEC_PER_SEC;
+          ts->tv_nsec  = remaining_us * NSEC_PER_USEC;
+        }
+
+        oneshot->running  = false;
+        oneshot->handler  = NULL;
+        oneshot->arg      = NULL;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: esp32_oneshot_current
+ *
+ * Description:
+ *   Get the current time.
+ *
+ * Input Parameters:
+ *   oneshot Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   usec    The maximum delay in us.
+ *
+ * Returned Value:
+ *   Zero (OK).
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_current(struct esp32_oneshot_s *oneshot, uint64_t *usec)
+{
+  /* Get the current counter value */
+
+  ESP32_TIM_GETCTR(oneshot->tim, usec);
+
+  *usec = *usec * (uint64_t)oneshot->resolution;
+
+  return OK;
+}
+
+#endif /* CONFIG_ESP32_ONESHOT */

arch/xtensa/src/esp32/esp32_oneshot.h

@@ -0,0 +1,202 @@
+/****************************************************************************
+ * arch/xtensa/src/esp32/esp32_oneshot.h
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_XTENSA_SRC_ESP32_ONESHOT_H
+#define __ARCH_XTENSA_SRC_ESP32_ONESHOT_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <time.h>
+
+#include "esp32_tim.h"
+
+#ifdef CONFIG_ESP32_ONESHOT
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/* This describes the callback function that will be invoked when the oneshot
+ * timer expires.  The oneshot fires, the client will receive:
+ *
+ *   arg - The opaque argument provided when the interrupt was registered
+ */
+
+typedef void (*oneshot_handler_t)(void *arg);
+
+/* The oneshot client must allocate an instance of this structure and call
+ * esp32_oneshot_initialize() before using the oneshot facilities.  The
+ * client should not access the contents of this structure directly since
+ * the contents are subject to change.
+ */
+
+struct esp32_oneshot_s
+{
+  uint8_t chan;                       /* The timer/counter in use */
+  volatile bool running;              /* True: the timer is running */
+  FAR struct esp32_tim_dev_s    *tim; /* Pointer returned by
+                                       * esp32_tim_init() */
+  volatile oneshot_handler_t handler; /* Oneshot expiration callback */
+  volatile void                 *arg; /* The argument that will accompany
+                                       * the callback */
+  uint32_t                resolution; /* us */
+};
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_oneshot_initialize
+ *
+ * Description:
+ *   Initialize the oneshot timer wrapper.
+ *
+ * Input Parameters:
+ *   oneshot    Allocated instance of the oneshot state structure.
+ *   chan       Timer counter channel to be used.
+ *   resolution The required resolution of the timer in units of
+ *              microseconds.  NOTE that the range is restricted to the
+ *              range of uint16_t (excluding zero).
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_initialize(struct esp32_oneshot_s *oneshot, int chan,
+                             uint16_t resolution);
+
+/****************************************************************************
+ * Name: esp32_oneshot_max_delay
+ *
+ * Description:
+ *   Determine the maximum delay of the one-shot timer (in microseconds).
+ *
+ * Input Parameters:
+ *   oneshot    Allocated instance of the oneshot state structure.
+ *   chan       The location in which to return the maximum delay in us.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_max_delay(struct esp32_oneshot_s *oneshot, uint64_t *usec);
+
+/****************************************************************************
+ * Name: esp32_oneshot_start
+ *
+ * Description:
+ *   Start the oneshot timer
+ *
+ * Input Parameters:
+ *   oneshot Allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   handler The function to call when the oneshot timer expires.
+ *   arg     An opaque argument that will accompany the callback.
+ *   ts      Provides the duration of the one shot timer.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_start(struct esp32_oneshot_s *oneshot,
+                        oneshot_handler_t handler, void *arg,
+                        const struct timespec *ts);
+
+/****************************************************************************
+ * Name: esp32_oneshot_cancel
+ *
+ * Description:
+ *   Cancel the oneshot timer and return the time remaining on the timer.
+ *
+ *
+ * Input Parameters:
+ *   oneshot Allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   ts      The location in which to return the time remaining on the
+ *           oneshot timer.  A time of zero is returned if the timer is
+ *           not running.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  A call to up_timer_cancel() when
+ *   the timer is not active should also return success; a negated errno
+ *   value is returned on any failure.
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_cancel(struct esp32_oneshot_s *oneshot,
+                         struct timespec *ts);
+
+/****************************************************************************
+ * Name: esp32_oneshot_current
+ *
+ * Description:
+ *   Get the current time.
+ *
+ * Input Parameters:
+ *   oneshot Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           esp32_oneshot_initialize();
+ *   usec    The maximum delay in us.
+ *
+ * Returned Value:
+ *   Zero (OK).
+ *
+ ****************************************************************************/
+
+int esp32_oneshot_current(struct esp32_oneshot_s *oneshot, uint64_t *usec);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CONFIG_ESP32_ONESHOT */
+#endif /* __ARCH_XTENSA_SRC_ESP32_ONESHOT_H */

arch/xtensa/src/esp32/esp32_oneshot_lowerhalf.c

@@ -0,0 +1,368 @@
+/****************************************************************************
+ * arch/xtensa/src/esp32/esp32_oneshot_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 <errno.h>
+#include <debug.h>
+#include <stdio.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/timers/oneshot.h>
+#include <nuttx/kmalloc.h>
+
+#include "esp32_oneshot.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct esp32_oneshot_lowerhalf_s
+{
+  /* This is the part of the lower half driver that is visible to the upper-
+   * half client of the driver.  This must be the first thing in this
+   * structure so that pointers to struct oneshot_lowerhalf_s are cast
+   * compatible to struct esp32_oneshot_lowerhalf_s and vice versa.
+   * That means, opaque pointers.
+   */
+
+  struct oneshot_lowerhalf_s        lh;  /* Lower half instance */
+  struct esp32_oneshot_s       oneshot;  /* ESP32-specific oneshot state */
+  oneshot_callback_t          callback;  /* Upper half Interrupt callback */
+  FAR void                        *arg;  /* Argument passed to handler */
+  uint16_t                  resolution;
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static void esp32_oneshot_lh_handler(void *arg);
+
+/* "Lower half" driver methods **********************************************/
+
+static int esp32_max_lh_delay(FAR struct oneshot_lowerhalf_s *lower,
+                              FAR struct timespec *ts);
+static int esp32_lh_start(FAR struct oneshot_lowerhalf_s *lower,
+                          oneshot_callback_t callback,
+                          FAR void *arg,
+                          FAR const struct timespec *ts);
+static int esp32_lh_cancel(FAR struct oneshot_lowerhalf_s *lower,
+                           FAR struct timespec *ts);
+static int esp32_lh_current(FAR struct oneshot_lowerhalf_s *lower,
+                            FAR struct timespec *ts);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* "Lower half" driver methods */
+
+static const struct oneshot_operations_s g_esp32_timer_ops =
+{
+  .max_delay = esp32_max_lh_delay,
+  .start     = esp32_lh_start,
+  .cancel    = esp32_lh_cancel,
+  .current   = esp32_lh_current
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_oneshot_lh_handler
+ *
+ * Description:
+ *   Timer expiration handler.
+ *
+ * Input Parameters:
+ *   arg - Should be the same argument provided when esp32_oneshot_start()
+ *         was called.
+ *
+ ****************************************************************************/
+
+static void esp32_oneshot_lh_handler(void *arg)
+{
+  FAR struct esp32_oneshot_lowerhalf_s *priv =
+    (FAR struct esp32_oneshot_lowerhalf_s *)arg;
+
+  DEBUGASSERT(priv != NULL);
+  DEBUGASSERT(priv->callback != NULL);
+
+  tmrinfo("Oneshot LH handler triggered\n");
+
+  /* Call the callback */
+
+  priv->callback(&priv->lh, priv->arg);
+
+  /* Restore state */
+
+  priv->callback = NULL;
+  priv->arg = NULL;
+}
+
+/****************************************************************************
+ * Name: esp32_max_lh_delay
+ *
+ * Description:
+ *   Determine the maximum delay of the one-shot timer (in microseconds).
+ *
+ * Input Parameters:
+ *   lower   An instance of the lower-half oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           oneshot_initialize();
+ *   ts      The location in which to return the maximum delay.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+static int esp32_max_lh_delay(FAR struct oneshot_lowerhalf_s *lower,
+                              FAR struct timespec *ts)
+{
+  DEBUGASSERT(ts != NULL);
+
+  /* The real maximum delay surpass the limit that timespec can
+   * reprent. Even using the better case: a resolution of
+   * 1 us.
+   * Therefore, here, fulfill the timespec with the
+   * maximum value it can represent.
+   */
+
+  ts->tv_sec  = UINT32_MAX;
+  ts->tv_nsec = NSEC_PER_SEC - 1;
+
+  tmrinfo("max sec=%" PRIu32 "\n", ts->tv_sec);
+  tmrinfo("max nsec=%ld\n", ts->tv_nsec);
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: esp32_lh_start
+ *
+ * Description:
+ *   Start the oneshot timer.
+ *
+ * Input Parameters:
+ *   lower    An instance of the lower-half oneshot state structure.  This
+ *            structure must have been previously initialized via a call to
+ *            oneshot_initialize();
+ *   callback The function to call when when the oneshot timer expires.
+ *            Inside the handler scope.
+ *   arg      A pointer to the argument that will accompany the callback.
+ *   ts       Provides the duration of the one shot timer.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned
+ *   on failure.
+ *
+ ****************************************************************************/
+
+static int esp32_lh_start(FAR struct oneshot_lowerhalf_s *lower,
+                          oneshot_callback_t callback,
+                          FAR void *arg,
+                          FAR const struct timespec *ts)
+{
+  FAR struct esp32_oneshot_lowerhalf_s *priv =
+    (FAR struct esp32_oneshot_lowerhalf_s *)lower;
+  int ret;
+  irqstate_t flags;
+
+  DEBUGASSERT(priv != NULL);
+  DEBUGASSERT(callback != NULL);
+  DEBUGASSERT(arg != NULL);
+  DEBUGASSERT(ts != NULL);
+
+  /* Save the callback information and start the timer */
+
+  flags          = enter_critical_section();
+  priv->callback = callback;
+  priv->arg      = arg;
+  ret            = esp32_oneshot_start(&priv->oneshot,
+                                       esp32_oneshot_lh_handler, priv, ts);
+  leave_critical_section(flags);
+
+  if (ret < 0)
+    {
+      tmrerr("ERROR: esp32_oneshot_start failed: %d\n", ret);
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: esp32_lh_cancel
+ *
+ * Description:
+ *   Cancel the oneshot timer and return the time remaining on the timer.
+ *
+ *   NOTE: This function may execute at a high rate with no timer running (as
+ *   when pre-emption is enabled and disabled).
+ *
+ * Input Parameters:
+ *   lower   Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           oneshot_initialize();
+ *   ts      The location in which to return the time remaining on the
+ *           oneshot timer.  A time of zero is returned if the timer is
+ *           not running.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  A call to up_timer_cancel() when
+ *   the timer is not active should also return success; a negated errno
+ *   value is returned on any failure.
+ *
+ ****************************************************************************/
+
+static int esp32_lh_cancel(FAR struct oneshot_lowerhalf_s *lower,
+                           FAR struct timespec *ts)
+{
+  FAR struct esp32_oneshot_lowerhalf_s *priv =
+    (FAR struct esp32_oneshot_lowerhalf_s *)lower;
+  irqstate_t flags;
+  int ret;
+
+  DEBUGASSERT(priv != NULL);
+
+  /* Cancel the timer */
+
+  flags          = enter_critical_section();
+  ret            = esp32_oneshot_cancel(&priv->oneshot, ts);
+  priv->callback = NULL;
+  priv->arg      = NULL;
+  leave_critical_section(flags);
+
+  if (ret < 0)
+    {
+      tmrerr("ERROR: esp32_oneshot_cancel failed: %d\n", flags);
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: esp32_lh_current
+ *
+ * Description:
+ *  Get the current time.
+ *
+ * Input Parameters:
+ *   lower   Caller allocated instance of the oneshot state structure.  This
+ *           structure must have been previously initialized via a call to
+ *           oneshot_initialize();
+ *   ts      The location in which to return the current time. A time of zero
+ *           is returned for the initialization moment.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success, a negated errno value is returned on
+ *   any failure.
+ *
+ ****************************************************************************/
+
+static int esp32_lh_current(FAR struct oneshot_lowerhalf_s *lower,
+                            FAR struct timespec *ts)
+{
+  FAR struct esp32_oneshot_lowerhalf_s *priv =
+    (FAR struct esp32_oneshot_lowerhalf_s *)lower;
+  uint64_t current_us;
+
+  DEBUGASSERT(priv != NULL);
+  DEBUGASSERT(ts != NULL);
+
+  esp32_oneshot_current(&priv->oneshot, &current_us);
+  ts->tv_sec  = current_us / USEC_PER_SEC;
+  current_us  = current_us - ts->tv_sec * USEC_PER_SEC;
+  ts->tv_nsec = current_us * NSEC_PER_USEC;
+
+  return OK;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: oneshot_initialize
+ *
+ * Description:
+ *   Initialize the oneshot timer and return a oneshot lower half driver
+ *   instance.
+ *
+ * Input Parameters:
+ *   chan       Timer counter channel to be used.
+ *   resolution The required resolution of the timer in units of
+ *              microseconds. NOTE that the range is restricted to the
+ *              range of uint16_t (excluding zero).
+ *
+ * Returned Value:
+ *   On success, a non-NULL instance of the oneshot lower-half driver is
+ *   returned. NULL is return on any failure.
+ *
+ ****************************************************************************/
+
+FAR struct oneshot_lowerhalf_s *oneshot_initialize(int chan,
+                                                   uint16_t resolution)
+{
+  FAR struct esp32_oneshot_lowerhalf_s *priv;
+  int ret;
+
+  /* Allocate an instance of the lower half driver */
+
+  priv = (FAR struct esp32_oneshot_lowerhalf_s *)kmm_zalloc(
+          sizeof(struct esp32_oneshot_lowerhalf_s));
+
+  if (priv == NULL)
+    {
+      tmrerr("ERROR: Failed to initialize oneshot state structure\n");
+      return NULL;
+    }
+
+  priv->lh.ops     = &g_esp32_timer_ops; /* Pointer to the LH operations */
+  priv->callback   = NULL;               /* No callback yet */
+  priv->arg        = NULL;               /* No arg yet */
+  priv->resolution = resolution;         /* Configured resolution */
+
+  /* Initialize esp32_oneshot_s structure */
+
+  ret = esp32_oneshot_initialize(&priv->oneshot, chan, resolution);
+  if (ret < 0)
+    {
+      tmrerr("ERROR: esp32_oneshot_initialize failed: %d\n", ret);
+      kmm_free(priv);
+      return NULL;
+    }
+
+  return &priv->lh;
+}

boards/xtensa/esp32/common/include/esp32_board_oneshot.h

@@ -1,5 +1,5 @@
 /****************************************************************************
- * boards/xtensa/esp32/common/include/esp32_board_tim.h
+ * boards/xtensa/esp32/common/include/esp32_board_oneshot.h
  *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
@@ -18,8 +18,8 @@
  *
  ****************************************************************************/
 
-#ifndef __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_TIM_H
+#ifndef __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_ONESHOT_H
-#define __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_TIM_H
+#define __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_ONESHOT_H
 
 /****************************************************************************
  * Included Files
@@ -27,6 +27,10 @@
 
 #include <nuttx/config.h>
 
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
 #ifndef __ASSEMBLY__
 
 /****************************************************************************
@@ -46,13 +50,17 @@ extern "C"
  * Public Function Prototypes
  ****************************************************************************/
 
-#ifdef CONFIG_TIMER
+#ifdef CONFIG_ONESHOT
 
 /****************************************************************************
- * Name: board_timer_init
+ * Name: esp32_oneshot_init
  *
  * Description:
- *   Configure the timer driver.
+ *   Configure the oneshot.
+ *
+ * Input Parameters:
+ *   timer      - Timer instance to be used as oneshot timer.
+ *   resolution - Oneshot timer resolution.
  *
  * Returned Value:
  *   Zero (OK) is returned on success; A negated errno value is returned
@@ -60,9 +68,9 @@ extern "C"
  *
  ****************************************************************************/
 
-int board_timer_init(void);
+int esp32_oneshot_init(int timer, uint16_t resolution);
 
-#endif /* CONFIG_TIMER */
+#endif /* CONFIG_ONESHOT */
 
 #undef EXTERN
 #if defined(__cplusplus)
@@ -70,4 +78,4 @@ int board_timer_init(void);
 #endif
 
 #endif /* __ASSEMBLY__ */
-#endif /* __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_TIM_H */
+#endif /* __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_BOARD_ONESHOT_H */

boards/xtensa/esp32/common/src/Make.defs

@@ -18,14 +18,14 @@
 #
 #############################################################################
 
-ifeq ($(CONFIG_TIMER),y)
-  CSRCS += esp32_board_tim.c
-endif
-
 ifeq ($(CONFIG_WATCHDOG),y)
   CSRCS += esp32_board_wdt.c
 endif
 
+ifeq ($(CONFIG_ONESHOT),y)
+  CSRCS += esp32_oneshot.c
+endif
+
 ifeq ($(CONFIG_I2C_DRIVER),y)
   CSRCS += esp32_board_i2c.c
 endif

boards/xtensa/esp32/common/src/esp32_oneshot.c

@@ -1,5 +1,5 @@
 /****************************************************************************
- * boards/xtensa/esp32/common/src/esp32_board_tim.c
+ * boards/xtensa/esp32/common/src/esp32_oneshot.c
  *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
@@ -27,30 +27,14 @@
 #include <debug.h>
 #include <sys/types.h>
 #include <nuttx/timers/timer.h>
-
+#include <nuttx/clock.h>
-#include "esp32_tim_lowerhalf.h"
+#include <nuttx/timers/oneshot.h>
-#include "esp32_board_tim.h"
+#include "esp32_board_oneshot.h"
 
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
 
-#ifdef CONFIG_ESP32_TIMER0
-#  define ESP32_TIMER0 (0)
-#endif
-
-#ifdef CONFIG_ESP32_TIMER1
-#  define ESP32_TIMER1 (1)
-#endif
-
-#ifdef CONFIG_ESP32_TIMER2
-#  define ESP32_TIMER2 (2)
-#endif
-
-#ifdef CONFIG_ESP32_TIMER3
-#  define ESP32_TIMER3 (3)
-#endif
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -67,55 +51,33 @@
  *
  ****************************************************************************/
 
-int board_timer_init(void)
+int esp32_oneshot_init(int timer, uint16_t resolution)
 {
   int ret = OK;
+  FAR struct oneshot_lowerhalf_s *os_lower = NULL;
 
-#ifdef CONFIG_ESP32_TIMER0
+  os_lower = oneshot_initialize(timer, resolution);
-  ret = esp32_timer_initialize("/dev/timer0", ESP32_TIMER0);
+  if (os_lower != NULL)
-  if (ret < 0)
     {
-      syslog(LOG_ERR,
+#if defined(CONFIG_CPULOAD_ONESHOT)
-             "ERROR: Failed to initialize timer driver: %d\n",
+      /* Configure the oneshot timer to support CPU load measurement */
-             ret);
-      goto errout;
-    }
-#endif
 
-#ifdef CONFIG_ESP32_TIMER1
+      nxsched_oneshot_extclk(os_lower);
-  ret = esp32_timer_initialize("/dev/timer1", ESP32_TIMER1);
+
-  if (ret < 0)
+#else
+      ret = oneshot_register("/dev/oneshot", os_lower);
+      if (ret < 0)
+        {
+          syslog(LOG_ERR,
+            "ERROR: Failed to register oneshot at /dev/oneshot: %d\n", ret);
+        }
+#endif /* CONFIG_CPULOAD_ONESHOT */
+    }
+  else
     {
-      syslog(LOG_ERR,
+      syslog(LOG_ERR, "ERROR: oneshot_initialize failed\n");
-             "ERROR: Failed to initialize timer driver: %d\n",
+      ret = -EBUSY;
-             ret);
-      goto errout;
     }
-#endif
 
-#ifdef CONFIG_ESP32_TIMER2
-  ret = esp32_timer_initialize("/dev/timer2", ESP32_TIMER2);
-  if (ret < 0)
-    {
-      syslog(LOG_ERR,
-             "ERROR: Failed to initialize timer driver: %d\n",
-             ret);
-      goto errout;
-    }
-#endif
-
-#ifdef CONFIG_ESP32_TIMER3
-  ret = esp32_timer_initialize("/dev/timer3", ESP32_TIMER3);
-  if (ret < 0)
-    {
-      syslog(LOG_ERR,
-             "ERROR: Failed to initialize timer driver: %d\n",
-             ret);
-      goto errout;
-    }
-#endif
-
-errout:
   return ret;
 }
-

boards/xtensa/esp32/esp32-devkitc/configs/oneshot/defconfig

@@ -0,0 +1,59 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_ARCH_LEDS is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_CMDPARMS is not set
+CONFIG_ALARM_ARCH=y
+CONFIG_ARCH="xtensa"
+CONFIG_ARCH_BOARD="esp32-devkitc"
+CONFIG_ARCH_BOARD_ESP32_DEVKITC=y
+CONFIG_ARCH_CHIP="esp32"
+CONFIG_ARCH_CHIP_ESP32=y
+CONFIG_ARCH_CHIP_ESP32WROVER=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARCH_XTENSA=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_ESP32_ONESHOT=y
+CONFIG_ESP32_TIMER0=y
+CONFIG_ESP32_TIMER1=y
+CONFIG_ESP32_TIMER2=y
+CONFIG_ESP32_TIMER3=y
+CONFIG_ESP32_UART0=y
+CONFIG_EXAMPLES_ONESHOT=y
+CONFIG_EXAMPLES_TIMER=y
+CONFIG_FS_PROCFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_IDLETHREAD_STACKSIZE=3072
+CONFIG_INTELHEX_BINARY=y
+CONFIG_MAX_TASKS=16
+CONFIG_MM_REGIONS=3
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_ONESHOT=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_SDCLONE_DISABLE=y
+CONFIG_SPI=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_SYSTEM_NSH=y
+CONFIG_TIMER=y
+CONFIG_TIMER_ARCH=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_USER_ENTRYPOINT="nsh_main"

boards/xtensa/esp32/esp32-devkitc/src/esp32-devkitc.h

@@ -50,6 +50,18 @@
 
 #define GPIO_MCP2515_IRQ      22
 
+/* TIMERS */
+
+#define TIMER0 0
+#define TIMER1 1
+#define TIMER2 2
+#define TIMER3 3
+
+/* ONESHOT */
+
+#define ONESHOT_TIMER         1
+#define ONESHOT_RESOLUTION_US 1
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/xtensa/esp32/esp32-devkitc/src/esp32_bringup.c

@@ -52,7 +52,11 @@
 #endif
 
 #ifdef CONFIG_TIMER
-#  include "esp32_board_tim.h"
+#include <esp32_tim_lowerhalf.h>
+#endif
+
+#ifdef CONFIG_ONESHOT
+#  include "esp32_board_oneshot.h"
 #endif
 
 #ifdef CONFIG_WATCHDOG
@@ -240,18 +244,69 @@ int esp32_bringup(void)
 
 #endif
 
+/* First, register the timer drivers and let timer 1 for oneshot
+ * if it is enabled.
+ */
 #ifdef CONFIG_TIMER
-  /* Configure timer driver */
 
-  ret = board_timer_init();
+#ifdef CONFIG_ESP32_TIMER0
+  ret = esp32_timer_initialize("/dev/timer0", TIMER0);
   if (ret < 0)
     {
       syslog(LOG_ERR,
-             "ERROR: Failed to initialize timer drivers: %d\n",
+             "ERROR: Failed to initialize timer driver: %d\n",
              ret);
+      return ret;
     }
 #endif
 
+#if defined(CONFIG_ESP32_TIMER1) && !defined(CONFIG_ONESHOT) 
+  ret = esp32_timer_initialize("/dev/timer1", TIMER1);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER2
+  ret = esp32_timer_initialize("/dev/timer2", TIMER2);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER3 
+  ret = esp32_timer_initialize("/dev/timer3", TIMER3);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#endif /* CONFIG_TIMER */
+
+  /* Now register one oneshot driver */
+
+#if defined(CONFIG_ONESHOT) && defined(CONFIG_ESP32_TIMER1)
+
+  ret = esp32_oneshot_init(ONESHOT_TIMER, ONESHOT_RESOLUTION_US);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: esp32_oneshot_init() failed: %d\n", ret);
+    }
+
+#endif /* CONFIG_ONESHOT */
+
 #ifdef CONFIG_USERLED
   /* Register the LED driver */
 

boards/xtensa/esp32/esp32-ethernet-kit/configs/oneshot/defconfig

@@ -0,0 +1,58 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_CMDPARMS is not set
+CONFIG_ALARM_ARCH=y
+CONFIG_ARCH="xtensa"
+CONFIG_ARCH_BOARD="esp32-ethernet-kit"
+CONFIG_ARCH_BOARD_ESP32_ETHERNETKIT=y
+CONFIG_ARCH_CHIP="esp32"
+CONFIG_ARCH_CHIP_ESP32=y
+CONFIG_ARCH_CHIP_ESP32WROVER=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARCH_XTENSA=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_ESP32_ONESHOT=y
+CONFIG_ESP32_TIMER0=y
+CONFIG_ESP32_TIMER1=y
+CONFIG_ESP32_TIMER2=y
+CONFIG_ESP32_TIMER3=y
+CONFIG_ESP32_UART0=y
+CONFIG_EXAMPLES_ONESHOT=y
+CONFIG_EXAMPLES_TIMER=y
+CONFIG_FS_PROCFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_IDLETHREAD_STACKSIZE=3072
+CONFIG_INTELHEX_BINARY=y
+CONFIG_MAX_TASKS=16
+CONFIG_MM_REGIONS=3
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_ONESHOT=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_SDCLONE_DISABLE=y
+CONFIG_SPI=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_SYSTEM_NSH=y
+CONFIG_TIMER=y
+CONFIG_TIMER_ARCH=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_USER_ENTRYPOINT="nsh_main"

boards/xtensa/esp32/esp32-ethernet-kit/src/esp32-ethernet-kit.h

@@ -39,6 +39,18 @@
 
 #define BUTTON_BOOT  0
 
+/* TIMERS */
+
+#define TIMER0 0
+#define TIMER1 1
+#define TIMER2 2
+#define TIMER3 3
+
+/* ONESHOT */
+
+#define ONESHOT_TIMER         1
+#define ONESHOT_RESOLUTION_US 1
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/xtensa/esp32/esp32-ethernet-kit/src/esp32_bringup.c

@@ -48,7 +48,11 @@
 #endif
 
 #ifdef CONFIG_TIMER
-#  include "esp32_board_tim.h"
+#include <esp32_tim_lowerhalf.h>
+#endif
+
+#ifdef CONFIG_ONESHOT
+#  include "esp32_board_oneshot.h"
 #endif
 
 #ifdef CONFIG_WATCHDOG
@@ -215,18 +219,69 @@ int esp32_bringup(void)
 
 #endif
 
+/* First, register the timer drivers and let timer 1 for oneshot
+ * if it is enabled.
+ */
 #ifdef CONFIG_TIMER
-  /* Configure timer driver */
 
-  ret = board_timer_init();
+#ifdef CONFIG_ESP32_TIMER0
+  ret = esp32_timer_initialize("/dev/timer0", TIMER0);
   if (ret < 0)
     {
       syslog(LOG_ERR,
-             "ERROR: Failed to initialize timer drivers: %d\n",
+             "ERROR: Failed to initialize timer driver: %d\n",
              ret);
+      return ret;
     }
 #endif
 
+#if defined(CONFIG_ESP32_TIMER1) && !defined(CONFIG_ONESHOT) 
+  ret = esp32_timer_initialize("/dev/timer1", TIMER1);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER2
+  ret = esp32_timer_initialize("/dev/timer2", TIMER2);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER3 
+  ret = esp32_timer_initialize("/dev/timer3", TIMER3);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#endif /* CONFIG_TIMER */
+
+  /* Now register one oneshot driver */
+
+#if defined(CONFIG_ONESHOT) && defined(CONFIG_ESP32_TIMER1)
+
+  ret = esp32_oneshot_init(ONESHOT_TIMER, ONESHOT_RESOLUTION_US);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: esp32_oneshot_init() failed: %d\n", ret);
+    }
+
+#endif /* CONFIG_ONESHOT */
+
 #ifdef CONFIG_USERLED
   /* Register the LED driver */
 

boards/xtensa/esp32/esp32-wrover-kit/configs/oneshot/defconfig

@@ -0,0 +1,58 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_CMDPARMS is not set
+CONFIG_ALARM_ARCH=y
+CONFIG_ARCH="xtensa"
+CONFIG_ARCH_BOARD="esp32-wrover-kit"
+CONFIG_ARCH_BOARD_ESP32_WROVERKIT=y
+CONFIG_ARCH_CHIP="esp32"
+CONFIG_ARCH_CHIP_ESP32=y
+CONFIG_ARCH_CHIP_ESP32WROVER=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARCH_XTENSA=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_ESP32_ONESHOT=y
+CONFIG_ESP32_TIMER0=y
+CONFIG_ESP32_TIMER1=y
+CONFIG_ESP32_TIMER2=y
+CONFIG_ESP32_TIMER3=y
+CONFIG_ESP32_UART0=y
+CONFIG_EXAMPLES_ONESHOT=y
+CONFIG_EXAMPLES_TIMER=y
+CONFIG_FS_PROCFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_IDLETHREAD_STACKSIZE=3072
+CONFIG_INTELHEX_BINARY=y
+CONFIG_MAX_TASKS=16
+CONFIG_MM_REGIONS=3
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_ONESHOT=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_SDCLONE_DISABLE=y
+CONFIG_SPI=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_SYSTEM_NSH=y
+CONFIG_TIMER=y
+CONFIG_TIMER_ARCH=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_USER_ENTRYPOINT="nsh_main"

boards/xtensa/esp32/esp32-wrover-kit/src/esp32-wrover-kit.h

@@ -45,6 +45,18 @@
 
 #define BUTTON_BOOT  0
 
+/* TIMERS */
+
+#define TIMER0 0
+#define TIMER1 1
+#define TIMER2 2
+#define TIMER3 3
+
+/* ONESHOT */
+
+#define ONESHOT_TIMER         1
+#define ONESHOT_RESOLUTION_US 1
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/

boards/xtensa/esp32/esp32-wrover-kit/src/esp32_bringup.c

@@ -49,7 +49,11 @@
 #endif
 
 #ifdef CONFIG_TIMER
-#  include "esp32_board_tim.h"
+#include <esp32_tim_lowerhalf.h>
+#endif
+
+#ifdef CONFIG_ONESHOT
+#  include "esp32_board_oneshot.h"
 #endif
 
 #ifdef CONFIG_WATCHDOG
@@ -224,18 +228,69 @@ int esp32_bringup(void)
 
 #endif
 
+/* First, register the timer drivers and let timer 1 for oneshot
+ * if it is enabled.
+ */
 #ifdef CONFIG_TIMER
-  /* Configure timer driver */
 
-  ret = board_timer_init();
+#ifdef CONFIG_ESP32_TIMER0
+  ret = esp32_timer_initialize("/dev/timer0", TIMER0);
   if (ret < 0)
     {
       syslog(LOG_ERR,
-             "ERROR: Failed to initialize timer drivers: %d\n",
+             "ERROR: Failed to initialize timer driver: %d\n",
              ret);
+      return ret;
     }
 #endif
 
+#if defined(CONFIG_ESP32_TIMER1) && !defined(CONFIG_ONESHOT) 
+  ret = esp32_timer_initialize("/dev/timer1", TIMER1);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER2
+  ret = esp32_timer_initialize("/dev/timer2", TIMER2);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#ifdef CONFIG_ESP32_TIMER3 
+  ret = esp32_timer_initialize("/dev/timer3", TIMER3);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize timer driver: %d\n",
+             ret);
+      return ret;
+    }
+#endif
+
+#endif /* CONFIG_TIMER */
+
+  /* Now register one oneshot driver */
+
+#if defined(CONFIG_ONESHOT) && defined(CONFIG_ESP32_TIMER1)
+
+  ret = esp32_oneshot_init(ONESHOT_TIMER, ONESHOT_RESOLUTION_US);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "ERROR: esp32_oneshot_init() failed: %d\n", ret);
+    }
+
+#endif /* CONFIG_ONESHOT */
+
 #ifdef CONFIG_USERLED
   /* Register the LED driver */