Example

Dependencies:   FXAS21002 FXOS8700Q

Revision:
0:11cc2b7889af
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/simple-mbed-cloud-client/mbed-cloud-client/sal-stack-nanostack-eventloop/source/event.c	Tue Nov 19 09:49:38 2019 +0000
@@ -0,0 +1,401 @@
+/*
+ * Copyright (c) 2014-2015 ARM Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ * Licensed 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.
+ */
+#include <string.h>
+#include "ns_types.h"
+#include "ns_list.h"
+#include "eventOS_event.h"
+#include "eventOS_scheduler.h"
+#include "timer_sys.h"
+#include "nsdynmemLIB.h"
+#include "ns_timer.h"
+#include "event.h"
+#include "platform/arm_hal_interrupt.h"
+
+
+typedef struct arm_core_tasklet {
+    int8_t id; /**< Event handler Tasklet ID */
+    void (*func_ptr)(arm_event_s *);
+    ns_list_link_t link;
+} arm_core_tasklet_t;
+
+static NS_LIST_DEFINE(arm_core_tasklet_list, arm_core_tasklet_t, link);
+static NS_LIST_DEFINE(event_queue_active, arm_event_storage_t, link);
+static NS_LIST_DEFINE(free_event_entry, arm_event_storage_t, link);
+
+// Statically allocate initial pool of events.
+#define STARTUP_EVENT_POOL_SIZE 10
+static arm_event_storage_t startup_event_pool[STARTUP_EVENT_POOL_SIZE];
+
+/** Curr_tasklet tell to core and platform which task_let is active, Core Update this automatic when switch Tasklet. */
+int8_t curr_tasklet = 0;
+
+
+static arm_core_tasklet_t *tasklet_dynamically_allocate(void);
+static arm_event_storage_t *event_dynamically_allocate(void);
+static arm_event_storage_t *event_core_get(void);
+static void event_core_write(arm_event_storage_t *event);
+
+static arm_core_tasklet_t *event_tasklet_handler_get(uint8_t tasklet_id)
+{
+    ns_list_foreach(arm_core_tasklet_t, cur, &arm_core_tasklet_list) {
+        if (cur->id == tasklet_id) {
+            return cur;
+        }
+    }
+    return NULL;
+}
+
+bool event_tasklet_handler_id_valid(uint8_t tasklet_id)
+{
+    return event_tasklet_handler_get(tasklet_id);
+}
+
+// XXX this can return 0, but 0 seems to mean "none" elsewhere? Or at least
+// curr_tasklet is reset to 0 in various places.
+static int8_t tasklet_get_free_id(void)
+{
+    /*(Note use of uint8_t to avoid overflow if we reach 0x7F)*/
+    for (uint8_t i = 0; i <= INT8_MAX; i++) {
+        if (!event_tasklet_handler_get(i)) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+
+int8_t eventOS_event_handler_create(void (*handler_func_ptr)(arm_event_s *), uint8_t init_event_type)
+{
+    arm_event_storage_t *event_tmp;
+
+    // XXX Do we really want to prevent multiple tasklets with same function?
+    ns_list_foreach(arm_core_tasklet_t, cur, &arm_core_tasklet_list) {
+        if (cur->func_ptr == handler_func_ptr) {
+            return -1;
+        }
+    }
+
+    //Allocate new
+    arm_core_tasklet_t *new = tasklet_dynamically_allocate();
+    if (!new) {
+        return -2;
+    }
+
+    event_tmp = event_core_get();
+    if (!event_tmp) {
+        ns_dyn_mem_free(new);
+        return -2;
+    }
+
+    //Fill in tasklet; add to list
+    new->id = tasklet_get_free_id();
+    new->func_ptr = handler_func_ptr;
+    ns_list_add_to_end(&arm_core_tasklet_list, new);
+
+    //Queue "init" event for the new task
+    event_tmp->data.receiver = new->id;
+    event_tmp->data.sender = 0;
+    event_tmp->data.event_type = init_event_type;
+    event_tmp->data.event_data = 0;
+    event_core_write(event_tmp);
+
+    return new->id;
+}
+
+int8_t eventOS_event_send(const arm_event_t *event)
+{
+    if (event_tasklet_handler_get(event->receiver)) {
+        arm_event_storage_t *event_tmp = event_core_get();
+        if (event_tmp) {
+            event_tmp->data = *event;
+            event_core_write(event_tmp);
+            return 0;
+        }
+    }
+    return -1;
+}
+
+void eventOS_event_send_user_allocated(arm_event_storage_t *event)
+{
+    event->allocator = ARM_LIB_EVENT_USER;
+    event_core_write(event);
+}
+
+void eventOS_event_send_timer_allocated(arm_event_storage_t *event)
+{
+    event->allocator = ARM_LIB_EVENT_TIMER;
+    event_core_write(event);
+}
+
+void eventOS_event_cancel_critical(arm_event_storage_t *event)
+{
+    ns_list_remove(&event_queue_active, event);
+}
+
+static arm_event_storage_t *event_dynamically_allocate(void)
+{
+    arm_event_storage_t *event = ns_dyn_mem_temporary_alloc(sizeof(arm_event_storage_t));
+    if (event) {
+        event->allocator = ARM_LIB_EVENT_DYNAMIC;
+    }
+    return event;
+}
+
+static arm_core_tasklet_t *tasklet_dynamically_allocate(void)
+{
+    return ns_dyn_mem_alloc(sizeof(arm_core_tasklet_t));
+}
+
+arm_event_storage_t *event_core_get(void)
+{
+    arm_event_storage_t *event;
+    platform_enter_critical();
+    event = ns_list_get_first(&free_event_entry);
+    if (event) {
+        ns_list_remove(&free_event_entry, event);
+    } else {
+        event = event_dynamically_allocate();
+    }
+    if (event) {
+        event->data.data_ptr = NULL;
+        event->data.priority = ARM_LIB_LOW_PRIORITY_EVENT;
+    }
+    platform_exit_critical();
+    return event;
+}
+
+void event_core_free_push(arm_event_storage_t *free)
+{
+    free->state = ARM_LIB_EVENT_UNQUEUED;
+
+    switch (free->allocator) {
+        case ARM_LIB_EVENT_STARTUP_POOL:
+            platform_enter_critical();
+            ns_list_add_to_start(&free_event_entry, free);
+            platform_exit_critical();
+            break;
+        case ARM_LIB_EVENT_DYNAMIC:
+            // Free all dynamically allocated events.
+            ns_dyn_mem_free(free);
+            break;
+        case ARM_LIB_EVENT_TIMER:
+            // Hand it back to the timer system
+            timer_sys_event_free(free);
+            break;
+        case ARM_LIB_EVENT_USER:
+        default:
+            break;
+    }
+}
+
+
+static arm_event_storage_t *event_core_read(void)
+{
+    platform_enter_critical();
+    arm_event_storage_t *event = ns_list_get_first(&event_queue_active);
+    if (event) {
+        event->state = ARM_LIB_EVENT_RUNNING;
+        ns_list_remove(&event_queue_active, event);
+    }
+    platform_exit_critical();
+    return event;
+}
+
+void event_core_write(arm_event_storage_t *event)
+{
+    platform_enter_critical();
+    bool added = false;
+    ns_list_foreach(arm_event_storage_t, event_tmp, &event_queue_active) {
+        // note enum ordering means we're checking if event_tmp is LOWER priority than event
+        if (event_tmp->data.priority > event->data.priority) {
+            ns_list_add_before(&event_queue_active, event_tmp, event);
+            added = true;
+            break;
+        }
+    }
+    if (!added) {
+        ns_list_add_to_end(&event_queue_active, event);
+    }
+    event->state = ARM_LIB_EVENT_QUEUED;
+
+    /* Wake From Idle */
+    platform_exit_critical();
+    eventOS_scheduler_signal();
+}
+
+// Requires lock to be held
+arm_event_storage_t *eventOS_event_find_by_id_critical(uint8_t tasklet_id, uint8_t event_id)
+{
+    ns_list_foreach(arm_event_storage_t, cur, &event_queue_active) {
+        if (cur->data.receiver == tasklet_id && cur->data.event_id == event_id) {
+            return cur;
+        }
+    }
+
+    return NULL;
+}
+
+/**
+ *
+ * \brief Initialize Nanostack Core.
+ *
+ * Function Initialize Nanostack Core, Socket Interface,Buffer memory and Send Init event to all Tasklett which are Defined.
+ *
+ */
+void eventOS_scheduler_init(void)
+{
+    /* Reset Event List variables */
+    ns_list_init(&free_event_entry);
+    ns_list_init(&event_queue_active);
+    ns_list_init(&arm_core_tasklet_list);
+
+    //Add first 10 entries to "free" list
+    for (unsigned i = 0; i < (sizeof(startup_event_pool) / sizeof(startup_event_pool[0])); i++) {
+        startup_event_pool[i].allocator = ARM_LIB_EVENT_STARTUP_POOL;
+        ns_list_add_to_start(&free_event_entry, &startup_event_pool[i]);
+    }
+
+    /* Init Generic timer module */
+    timer_sys_init();               //initialize timer
+    /* Set Tasklett switcher to Idle */
+    curr_tasklet = 0;
+
+}
+
+int8_t eventOS_scheduler_get_active_tasklet(void)
+{
+    return curr_tasklet;
+}
+
+void eventOS_scheduler_set_active_tasklet(int8_t tasklet)
+{
+    curr_tasklet = tasklet;
+}
+
+int eventOS_scheduler_timer_stop(void)
+{
+    timer_sys_disable();
+    if (ns_timer_sleep() != 0) {
+        return 1;
+    }
+    return 0;
+}
+
+int eventOS_scheduler_timer_synch_after_sleep(uint32_t sleep_ticks)
+{
+    //Update MS to 10ms ticks
+    sleep_ticks /= 10;
+    sleep_ticks++;
+    system_timer_tick_update(sleep_ticks);
+    if (timer_sys_wakeup() == 0) {
+        return 0;
+    }
+    return -1;
+}
+
+/**
+ *
+ * \brief Infinite Event Read Loop.
+ *
+ * Function Read and handle Cores Event and switch/enable tasklet which are event receiver. WhenEvent queue is empty it goes to sleep
+ *
+ */
+bool eventOS_scheduler_dispatch_event(void)
+{
+    curr_tasklet = 0;
+
+    arm_event_storage_t *cur_event = event_core_read();
+    if (!cur_event) {
+        return false;
+    }
+
+    curr_tasklet = cur_event->data.receiver;
+
+    arm_core_tasklet_t *tasklet = event_tasklet_handler_get(curr_tasklet);
+    /* Do not bother with check for NULL - tasklets cannot be deleted,
+     * and user-facing API eventOS_event_send() has already checked the tasklet
+     * exists, so there is no possible issue there.
+     *
+     * For eventOS_event_send_user_allocated(), it would be a non-recoverable
+     * error to not deliver the message - we have to have a receiver to pass
+     * ownership to. If the lookup fails, let it crash. We want the send call
+     * itself to return void to simplify logic.
+     */
+
+    /* Tasklet Scheduler Call */
+    tasklet->func_ptr(&cur_event->data);
+    event_core_free_push(cur_event);
+
+    /* Set Current Tasklet to Idle state */
+    curr_tasklet = 0;
+
+    return true;
+}
+
+void eventOS_scheduler_run_until_idle(void)
+{
+    while (eventOS_scheduler_dispatch_event());
+}
+
+/**
+ *
+ * \brief Infinite Event Read Loop.
+ *
+ * Function Read and handle Cores Event and switch/enable tasklet which are event receiver. WhenEvent queue is empty it goes to sleep
+ *
+ */
+NS_NORETURN void eventOS_scheduler_run(void)
+{
+    while (1) {
+        if (!eventOS_scheduler_dispatch_event()) {
+            eventOS_scheduler_idle();
+        }
+    }
+}
+
+void eventOS_cancel(arm_event_storage_t *event)
+{
+    if (!event) {
+        return;
+    }
+
+    platform_enter_critical();
+
+    /*
+     * Notify timer of cancellation.
+     */
+    if (event->allocator == ARM_LIB_EVENT_TIMER) {
+        timer_sys_event_cancel_critical(event);
+    }
+
+    /*
+     * Remove event from the list,
+     * Only queued can be removed, unqued are either timers or stale pointers
+     * RUNNING cannot be removed, we are currenly "in" that event.
+     */
+    if (event->state == ARM_LIB_EVENT_QUEUED) {
+        eventOS_event_cancel_critical(event);
+    }
+
+    /*
+     * Push back to "free" state
+     */
+    if (event->state != ARM_LIB_EVENT_RUNNING) {
+        event_core_free_push(event);
+    }
+
+    platform_exit_critical();
+}