CMSIS_5/CMSIS/RTOS2/RTX/Source/rtx_kernel.c

/*
 * Copyright (c) 2013-2023 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
 *
 * 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.
 *
 * -----------------------------------------------------------------------------
 *
 * Project:     CMSIS-RTOS RTX
 * Title:       Kernel functions
 *
 * -----------------------------------------------------------------------------
 */

#include "rtx_lib.h"


//  OS Runtime Information
osRtxInfo_t osRtxInfo __attribute__((section(".data.os"))) =
//lint -e{785} "Initialize only OS ID, OS Version and Kernel State"
{ .os_id = osRtxKernelId, .version = osRtxVersionKernel, .kernel.state = osRtxKernelInactive };


//  ==== Helper functions ====

/// Block Kernel (disable: thread switching, time tick, post ISR processing).
static void KernelBlock (void) {

  OS_Tick_Disable();

  osRtxInfo.kernel.blocked = 1U;
  __DSB();

  if (GetPendSV() != 0U) {
    ClrPendSV();
    osRtxInfo.kernel.pendSV = 1U;
  }
}

/// Unblock Kernel
static void KernelUnblock (void) {

  osRtxInfo.kernel.blocked = 0U;
  __DSB();

  if (osRtxInfo.kernel.pendSV != 0U) {
    osRtxInfo.kernel.pendSV = 0U;
    SetPendSV();
  }

  OS_Tick_Enable();
}

// Get Kernel sleep time
static uint32_t GetKernelSleepTime (void) {
  const os_thread_t *thread;
  const os_timer_t  *timer;
  uint32_t           delay;

  delay = osWaitForever;

  // Check Thread Delay list
  thread = osRtxInfo.thread.delay_list;
  if (thread != NULL) {
    delay = thread->delay;
  }

#ifdef RTX_THREAD_WATCHDOG
  // Check Thread Watchdog list
  thread = osRtxInfo.thread.wdog_list;
  if (thread != NULL) {
    if (thread->wdog_tick < delay) {
      delay = thread->wdog_tick;
    }
  }
#endif

  // Check Active Timer list
  timer = osRtxInfo.timer.list;
  if (timer != NULL) {
    if (timer->tick < delay) {
      delay = timer->tick;
    }
  }

  return delay;
}


//  ==== Service Calls ====

/// Initialize the RTOS Kernel.
/// \note API identical to osKernelInitialize
static osStatus_t svcRtxKernelInitialize (void) {

  if (osRtxInfo.kernel.state == osRtxKernelReady) {
    EvrRtxKernelInitialized();
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osOK;
  }
  if (osRtxInfo.kernel.state != osRtxKernelInactive) {
    EvrRtxKernelError((int32_t)osError);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osError;
  }

#ifdef RTX_TZ_CONTEXT
  // Initialize Secure Process Stack
  if (TZ_InitContextSystem_S() == 0U) {
    EvrRtxKernelError(osRtxErrorTZ_InitContext_S);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osError;
  }
#endif

  // Initialize osRtxInfo
  (void)memset(&osRtxInfo.kernel, 0, sizeof(osRtxInfo) - offsetof(osRtxInfo_t, kernel));

  osRtxInfo.isr_queue.data = osRtxConfig.isr_queue.data;
  osRtxInfo.isr_queue.max  = osRtxConfig.isr_queue.max;

  osRtxInfo.thread.robin.timeout = osRtxConfig.robin_timeout;

  // Initialize Memory Pools (Variable Block Size)
  if (osRtxMemoryInit(osRtxConfig.mem.common_addr, osRtxConfig.mem.common_size) != 0U) {
    osRtxInfo.mem.common = osRtxConfig.mem.common_addr;
  }
  if (osRtxMemoryInit(osRtxConfig.mem.stack_addr, osRtxConfig.mem.stack_size) != 0U) {
    osRtxInfo.mem.stack = osRtxConfig.mem.stack_addr;
  } else {
    osRtxInfo.mem.stack = osRtxInfo.mem.common;
  }
  if (osRtxMemoryInit(osRtxConfig.mem.mp_data_addr, osRtxConfig.mem.mp_data_size) != 0U) {
    osRtxInfo.mem.mp_data = osRtxConfig.mem.mp_data_addr;
  } else {
    osRtxInfo.mem.mp_data = osRtxInfo.mem.common;
  }
  if (osRtxMemoryInit(osRtxConfig.mem.mq_data_addr, osRtxConfig.mem.mq_data_size) != 0U) {
    osRtxInfo.mem.mq_data = osRtxConfig.mem.mq_data_addr;
  } else {
    osRtxInfo.mem.mq_data = osRtxInfo.mem.common;
  }

  // Initialize Memory Pools (Fixed Block Size)
  if (osRtxConfig.mpi.stack != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.stack,
                              osRtxConfig.mpi.stack->max_blocks,
                              osRtxConfig.mpi.stack->block_size,
                              osRtxConfig.mpi.stack->block_base);
    osRtxInfo.mpi.stack = osRtxConfig.mpi.stack;
  }
  if (osRtxConfig.mpi.thread != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.thread,
                              osRtxConfig.mpi.thread->max_blocks,
                              osRtxConfig.mpi.thread->block_size,
                              osRtxConfig.mpi.thread->block_base);
    osRtxInfo.mpi.thread = osRtxConfig.mpi.thread;
  }
  if (osRtxConfig.mpi.timer != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.timer,
                              osRtxConfig.mpi.timer->max_blocks,
                              osRtxConfig.mpi.timer->block_size,
                              osRtxConfig.mpi.timer->block_base);
    osRtxInfo.mpi.timer = osRtxConfig.mpi.timer;
  }
  if (osRtxConfig.mpi.event_flags != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.event_flags,
                              osRtxConfig.mpi.event_flags->max_blocks,
                              osRtxConfig.mpi.event_flags->block_size,
                              osRtxConfig.mpi.event_flags->block_base);
    osRtxInfo.mpi.event_flags = osRtxConfig.mpi.event_flags;
  }
  if (osRtxConfig.mpi.mutex != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.mutex,
                              osRtxConfig.mpi.mutex->max_blocks,
                              osRtxConfig.mpi.mutex->block_size,
                              osRtxConfig.mpi.mutex->block_base);
    osRtxInfo.mpi.mutex = osRtxConfig.mpi.mutex;
  }
  if (osRtxConfig.mpi.semaphore != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.semaphore,
                              osRtxConfig.mpi.semaphore->max_blocks,
                              osRtxConfig.mpi.semaphore->block_size,
                              osRtxConfig.mpi.semaphore->block_base);
    osRtxInfo.mpi.semaphore = osRtxConfig.mpi.semaphore;
  }
  if (osRtxConfig.mpi.memory_pool != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.memory_pool,
                              osRtxConfig.mpi.memory_pool->max_blocks,
                              osRtxConfig.mpi.memory_pool->block_size,
                              osRtxConfig.mpi.memory_pool->block_base);
    osRtxInfo.mpi.memory_pool = osRtxConfig.mpi.memory_pool;
  }
  if (osRtxConfig.mpi.message_queue != NULL) {
    (void)osRtxMemoryPoolInit(osRtxConfig.mpi.message_queue,
                              osRtxConfig.mpi.message_queue->max_blocks,
                              osRtxConfig.mpi.message_queue->block_size,
                              osRtxConfig.mpi.message_queue->block_base);
    osRtxInfo.mpi.message_queue = osRtxConfig.mpi.message_queue;
  }

  osRtxInfo.kernel.state = osRtxKernelReady;

  EvrRtxKernelInitialized();

  return osOK;
}

///  Get RTOS Kernel Information.
/// \note API identical to osKernelGetInfo
static osStatus_t svcRtxKernelGetInfo (osVersion_t *version, char *id_buf, uint32_t id_size) {
  uint32_t size;

  if (version != NULL) {
    version->api    = osRtxVersionAPI;
    version->kernel = osRtxVersionKernel;
  }

  if ((id_buf != NULL) && (id_size != 0U)) {
    if (id_size > sizeof(osRtxKernelId)) {
      size = sizeof(osRtxKernelId);
    } else {
      size = id_size;
    }
    (void)memcpy(id_buf, osRtxKernelId, size);
  }

  EvrRtxKernelInfoRetrieved(version, id_buf, id_size);

  return osOK;
}

/// Get the current RTOS Kernel state.
/// \note API identical to osKernelGetState
static osKernelState_t svcRtxKernelGetState (void) {
  osKernelState_t state = osRtxKernelState();
  EvrRtxKernelGetState(state);
  return state;
}

/// Start the RTOS Kernel scheduler.
/// \note API identical to osKernelStart
static osStatus_t svcRtxKernelStart (void) {
  os_thread_t *thread;

  if (osRtxInfo.kernel.state != osRtxKernelReady) {
    EvrRtxKernelError(osRtxErrorKernelNotReady);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osError;
  }

  // Thread startup (Idle and Timer Thread)
  if (!osRtxThreadStartup()) {
    EvrRtxKernelError((int32_t)osError);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osError;
  }

  // Setup SVC and PendSV System Service Calls
  SVC_Setup();

  // Setup RTOS Tick
  if (OS_Tick_Setup(osRtxConfig.tick_freq, OS_TICK_HANDLER) != 0) {
    EvrRtxKernelError((int32_t)osError);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osError;
  }
  osRtxInfo.tick_irqn = OS_Tick_GetIRQn();

  // Enable RTOS Tick
  OS_Tick_Enable();

  // Switch to Ready Thread with highest Priority
  thread = osRtxThreadListGet(&osRtxInfo.thread.ready);
  osRtxThreadSwitch(thread);

  osRtxInfo.kernel.state = osRtxKernelRunning;

  EvrRtxKernelStarted();

  return osOK;
}

/// Lock the RTOS Kernel scheduler.
/// \note API identical to osKernelLock
static int32_t svcRtxKernelLock (void) {
  int32_t lock;

  switch (osRtxInfo.kernel.state) {
    case osRtxKernelRunning:
#ifdef RTX_SAFETY_CLASS
      // Check the safety class
      if ((osRtxThreadGetRunning()->attr >> osRtxAttrClass_Pos) <
          (osRtxInfo.kernel.protect >> osRtxKernelProtectClass_Pos)) {
        EvrRtxKernelError((int32_t)osErrorSafetyClass);
        lock = (int32_t)osErrorSafetyClass;
        break;
      }
#endif
      osRtxInfo.kernel.state = osRtxKernelLocked;
      EvrRtxKernelLocked(0);
      lock = 0;
      break;
    case osRtxKernelLocked:
      EvrRtxKernelLocked(1);
      lock = 1;
      break;
    default:
      EvrRtxKernelError((int32_t)osError);
      lock = (int32_t)osError;
      break;
  }
  return lock;
}

/// Unlock the RTOS Kernel scheduler.
/// \note API identical to osKernelUnlock
static int32_t svcRtxKernelUnlock (void) {
  int32_t lock;

  switch (osRtxInfo.kernel.state) {
    case osRtxKernelRunning:
      EvrRtxKernelUnlocked(0);
      lock = 0;
      break;
    case osRtxKernelLocked:
      osRtxInfo.kernel.state = osRtxKernelRunning;
      EvrRtxKernelUnlocked(1);
      lock = 1;
      break;
    default:
      EvrRtxKernelError((int32_t)osError);
      lock = (int32_t)osError;
      break;
  }
  return lock;
}

/// Restore the RTOS Kernel scheduler lock state.
/// \note API identical to osKernelRestoreLock
static int32_t svcRtxKernelRestoreLock (int32_t lock) {
  int32_t lock_new;

  switch (osRtxInfo.kernel.state) {
    case osRtxKernelRunning:
    case osRtxKernelLocked:
#ifdef RTX_SAFETY_CLASS
      // Check the safety class
      if ((osRtxThreadGetRunning()->attr >> osRtxAttrClass_Pos) <
          (osRtxInfo.kernel.protect >> osRtxKernelProtectClass_Pos)) {
        EvrRtxKernelError((int32_t)osErrorSafetyClass);
        lock_new = (int32_t)osErrorSafetyClass;
        break;
      }
#endif
      switch (lock) {
        case 0:
          osRtxInfo.kernel.state = osRtxKernelRunning;
          EvrRtxKernelLockRestored(0);
          lock_new = 0;
          break;
        case 1:
          osRtxInfo.kernel.state = osRtxKernelLocked;
          EvrRtxKernelLockRestored(1);
          lock_new = 1;
          break;
        default:
          EvrRtxKernelError((int32_t)osError);
          lock_new = (int32_t)osError;
          break;
      }
      break;
    default:
      EvrRtxKernelError((int32_t)osError);
      lock_new = (int32_t)osError;
      break;
  }
  return lock_new;
}

/// Suspend the RTOS Kernel scheduler.
/// \note API identical to osKernelSuspend
static uint32_t svcRtxKernelSuspend (void) {
  uint32_t delay;

  if (osRtxInfo.kernel.state != osRtxKernelRunning) {
    EvrRtxKernelError(osRtxErrorKernelNotRunning);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return 0U;
  }

#ifdef RTX_SAFETY_CLASS
  // Check the safety class
  if ((osRtxThreadGetRunning()->attr >> osRtxAttrClass_Pos) <
      (osRtxInfo.kernel.protect >> osRtxKernelProtectClass_Pos)) {
    EvrRtxKernelError((int32_t)osErrorSafetyClass);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return 0U;
  }
#endif

  KernelBlock();

  osRtxInfo.kernel.state = osRtxKernelSuspended;

  delay = GetKernelSleepTime();

  EvrRtxKernelSuspended(delay);

  return delay;
}

/// Resume the RTOS Kernel scheduler.
/// \note API identical to osKernelResume
static void svcRtxKernelResume (uint32_t sleep_ticks) {
  os_thread_t *thread;
  os_timer_t  *timer;
  uint32_t     delay;
  uint32_t     ticks, kernel_tick;

  if (osRtxInfo.kernel.state != osRtxKernelSuspended) {
    EvrRtxKernelResumed();
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return;
  }

  delay = GetKernelSleepTime();
  if (sleep_ticks >= delay) {
    ticks = delay - 1U;
  } else {
    ticks = sleep_ticks;
  }

  // Update Thread Delay sleep ticks
  thread = osRtxInfo.thread.delay_list;
  if (thread != NULL) {
    thread->delay -= ticks;
  }

  // Update Timer sleep ticks
  timer = osRtxInfo.timer.list;
  if (timer != NULL) {
    timer->tick -= ticks;
  }

#ifdef RTX_THREAD_WATCHDOG
  // Update Thread Watchdog sleep ticks
  thread = osRtxInfo.thread.wdog_list;
  if (thread != NULL) {
    thread->wdog_tick -= ticks;
  }
#endif

  kernel_tick = osRtxInfo.kernel.tick + sleep_ticks;
  osRtxInfo.kernel.tick += ticks;

  while (osRtxInfo.kernel.tick != kernel_tick) {
    osRtxInfo.kernel.tick++;

    // Process Thread Delays
    osRtxThreadDelayTick();

    // Process Timers
    if (osRtxInfo.timer.tick != NULL) {
      osRtxInfo.timer.tick();
    }

#ifdef RTX_THREAD_WATCHDOG
    // Process Watchdog Timers
    osRtxThreadWatchdogTick();
#endif
  }

  osRtxInfo.kernel.state = osRtxKernelRunning;

  osRtxThreadDispatch(NULL);

  KernelUnblock();

  EvrRtxKernelResumed();
}

#ifdef RTX_SAFETY_CLASS

/// Protect the RTOS Kernel scheduler access.
/// \note API identical to osKernelProtect
static osStatus_t svcRtxKernelProtect (uint32_t safety_class) {
  uint32_t   thread_class;
  osStatus_t status;

  // Check parameters
  if (safety_class > 0x0FU) {
    EvrRtxKernelError((int32_t)osErrorParameter);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osErrorParameter;
  }

  switch (osRtxInfo.kernel.state) {
    case osRtxKernelInactive:
      EvrRtxKernelError(osRtxErrorKernelNotReady);
      status = osError;
      break;
    case osRtxKernelReady:
      osRtxInfo.kernel.protect &= (uint8_t)~osRtxKernelProtectClass_Msk;
      osRtxInfo.kernel.protect |= (uint8_t)(safety_class << osRtxKernelProtectClass_Pos);
      EvrRtxKernelProtected();
      status = osOK;
      break;
    case osRtxKernelRunning:
      // Check the safety class
      thread_class = (uint32_t)osRtxThreadGetRunning()->attr >> osRtxAttrClass_Pos;
      if ((safety_class > thread_class) ||
          (thread_class < ((uint32_t)osRtxInfo.kernel.protect >> osRtxKernelProtectClass_Pos))) {
        EvrRtxKernelError((int32_t)osErrorSafetyClass);
        status = osErrorSafetyClass;
        break;
      }
      osRtxInfo.kernel.protect &= (uint8_t)~osRtxKernelProtectClass_Msk;
      osRtxInfo.kernel.protect |= (uint8_t)(safety_class << osRtxKernelProtectClass_Pos);
      EvrRtxKernelProtected();
      status = osOK;
      break;
    case osRtxKernelLocked:
    case osRtxKernelSuspended:
      EvrRtxKernelError(osRtxErrorKernelNotRunning);
      status = osError;
      break;
    default:
      // Should never come here
      status = osError;
      break;
  }

  return status;
}

/// Destroy objects for specified safety classes.
/// \note API identical to osKernelDestroyClass
static osStatus_t svcRtxKernelDestroyClass (uint32_t safety_class, uint32_t mode) {
  os_thread_t *thread;
  os_thread_t *thread_next;

  // Check parameters
  if (safety_class > 0x0FU) {
    EvrRtxKernelError((int32_t)osErrorParameter);
    //lint -e{904} "Return statement before end of function" [MISRA Note 1]
    return osErrorParameter;
  }

  // Check running thread safety class (when called from thread)
  thread = osRtxThreadGetRunning();
  if ((thread != NULL) && IsSVCallIrq()) {
    if ((((mode & osSafetyWithSameClass)  != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) < (uint8_t)safety_class)) ||
        (((mode & osSafetyWithLowerClass) != 0U) &&
         (((thread->attr >> osRtxAttrClass_Pos) + 1U) < (uint8_t)safety_class))) {
      EvrRtxKernelError((int32_t)osErrorSafetyClass);
      //lint -e{904} "Return statement before end of function" [MISRA Note 1]
      return osErrorSafetyClass;
    }
  }

  // Delete RTOS objects for safety class
  osRtxMutexDeleteClass(safety_class, mode);
  osRtxSemaphoreDeleteClass(safety_class, mode);
  osRtxMemoryPoolDeleteClass(safety_class, mode);
  osRtxMessageQueueDeleteClass(safety_class, mode);
  osRtxEventFlagsDeleteClass(safety_class, mode);
  osRtxTimerDeleteClass(safety_class, mode);

  // Threads in Wait List
  thread = osRtxInfo.thread.wait_list;
  while (thread != NULL) {
    thread_next = thread->delay_next;
    if ((((mode & osSafetyWithSameClass)  != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) == (uint8_t)safety_class)) ||
        (((mode & osSafetyWithLowerClass) != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) <  (uint8_t)safety_class))) {
      osRtxThreadListRemove(thread);
      osRtxThreadDelayRemove(thread);
#ifdef RTX_THREAD_WATCHDOG
      osRtxThreadWatchdogRemove(thread);
#endif
      osRtxMutexOwnerRelease(thread->mutex_list);
      osRtxThreadJoinWakeup(thread);
      osRtxThreadDestroy(thread);
    }
    thread = thread_next;
  }

  // Threads in Delay List
  thread = osRtxInfo.thread.delay_list;
  while (thread != NULL) {
    thread_next = thread->delay_next;
    if ((((mode & osSafetyWithSameClass)  != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) == (uint8_t)safety_class)) ||
        (((mode & osSafetyWithLowerClass) != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) <  (uint8_t)safety_class))) {
      osRtxThreadListRemove(thread);
      osRtxThreadDelayRemove(thread);
#ifdef RTX_THREAD_WATCHDOG
      osRtxThreadWatchdogRemove(thread);
#endif
      osRtxMutexOwnerRelease(thread->mutex_list);
      osRtxThreadJoinWakeup(thread);
      osRtxThreadDestroy(thread);
    }
    thread = thread_next;
  }

  // Threads in Ready List
  thread = osRtxInfo.thread.ready.thread_list;
  while (thread != NULL) {
    thread_next = thread->thread_next;
    if ((((mode & osSafetyWithSameClass)  != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) == (uint8_t)safety_class)) ||
        (((mode & osSafetyWithLowerClass) != 0U) &&
         ((thread->attr >> osRtxAttrClass_Pos) <  (uint8_t)safety_class))) {
      osRtxThreadListRemove(thread);
#ifdef RTX_THREAD_WATCHDOG
      osRtxThreadWatchdogRemove(thread);
#endif
      osRtxMutexOwnerRelease(thread->mutex_list);
      osRtxThreadJoinWakeup(thread);
      osRtxThreadDestroy(thread);
    }
    thread = thread_next;
  }

  // Running Thread
  thread = osRtxThreadGetRunning();
  if ((thread != NULL) &&
      ((((mode & osSafetyWithSameClass)  != 0U) &&
        ((thread->attr >> osRtxAttrClass_Pos) == (uint8_t)safety_class)) ||
       (((mode & osSafetyWithLowerClass) != 0U) &&
        ((thread->attr >> osRtxAttrClass_Pos) <  (uint8_t)safety_class)))) {
    if ((osRtxKernelGetState() != osRtxKernelRunning) ||
        (osRtxInfo.thread.ready.thread_list == NULL)) {
      osRtxThreadDispatch(NULL);
      EvrRtxKernelError((int32_t)osErrorResource);
      //lint -e{904} "Return statement before end of function" [MISRA Note 1]
      return osErrorResource;
    }
#ifdef RTX_THREAD_WATCHDOG
    osRtxThreadWatchdogRemove(thread);
#endif
    osRtxMutexOwnerRelease(thread->mutex_list);
    osRtxThreadJoinWakeup(thread);
    // Switch to next Ready Thread
    osRtxThreadSwitch(osRtxThreadListGet(&osRtxInfo.thread.ready));
    // Update Stack Pointer
    thread->sp = __get_PSP();
#ifdef RTX_STACK_CHECK
    // Check Stack usage
    if (!osRtxThreadStackCheck(thread)) {
      osRtxThreadSetRunning(osRtxInfo.thread.run.next);
      (void)osRtxKernelErrorNotify(osRtxErrorStackOverflow, thread);
    }
#endif
    // Mark running thread as deleted
    osRtxThreadSetRunning(NULL);
    // Destroy Thread
    osRtxThreadDestroy(thread);
  } else {
    osRtxThreadDispatch(NULL);
  }

  return osOK;
}

#endif

/// Get the RTOS kernel tick count.
/// \note API identical to osKernelGetTickCount
static uint32_t svcRtxKernelGetTickCount (void) {
  EvrRtxKernelGetTickCount(osRtxInfo.kernel.tick);
  return osRtxInfo.kernel.tick;
}

/// Get the RTOS kernel tick frequency.
/// \note API identical to osKernelGetTickFreq
static uint32_t svcRtxKernelGetTickFreq (void) {
  EvrRtxKernelGetTickFreq(osRtxConfig.tick_freq);
  return osRtxConfig.tick_freq;
}

/// Get the RTOS kernel system timer count.
/// \note API identical to osKernelGetSysTimerCount
static uint32_t svcRtxKernelGetSysTimerCount (void) {
  uint32_t tick;
  uint32_t count;

  tick  = (uint32_t)osRtxInfo.kernel.tick;
  count = OS_Tick_GetCount();
  if (OS_Tick_GetOverflow() != 0U) {
    count = OS_Tick_GetCount();
    tick++;
  }
  count += tick * OS_Tick_GetInterval();
  EvrRtxKernelGetSysTimerCount(count);
  return count;
}

/// Get the RTOS kernel system timer frequency.
/// \note API identical to osKernelGetSysTimerFreq
static uint32_t svcRtxKernelGetSysTimerFreq (void) {
  uint32_t freq = OS_Tick_GetClock();
  EvrRtxKernelGetSysTimerFreq(freq);
  return freq;
}

//  Service Calls definitions
//lint ++flb "Library Begin" [MISRA Note 11]
SVC0_0 (KernelInitialize,       osStatus_t)
SVC0_3 (KernelGetInfo,          osStatus_t, osVersion_t *, char *, uint32_t)
SVC0_0 (KernelStart,            osStatus_t)
SVC0_0 (KernelLock,             int32_t)
SVC0_0 (KernelUnlock,           int32_t)
SVC0_1 (KernelRestoreLock,      int32_t, int32_t)
SVC0_0 (KernelSuspend,          uint32_t)
SVC0_1N(KernelResume,           void, uint32_t)
#ifdef RTX_SAFETY_CLASS
SVC0_1 (KernelProtect,          osStatus_t, uint32_t)
SVC0_2 (KernelDestroyClass,     osStatus_t, uint32_t, uint32_t)
#endif
SVC0_0 (KernelGetState,         osKernelState_t)
SVC0_0 (KernelGetTickCount,     uint32_t)
SVC0_0 (KernelGetTickFreq,      uint32_t)
SVC0_0 (KernelGetSysTimerCount, uint32_t)
SVC0_0 (KernelGetSysTimerFreq,  uint32_t)
//lint --flb "Library End"


//  ==== Library functions ====

/// RTOS Kernel Pre-Initialization Hook
//lint -esym(759,osRtxKernelBeforeInit) "Prototype in header"
//lint -esym(765,osRtxKernelBeforeInit) "Global scope (can be overridden)"
//lint -esym(522,osRtxKernelBeforeInit) "Can be overridden (do not lack side-effects)"
__WEAK void osRtxKernelBeforeInit (void) {
}

/// RTOS Kernel Error Notification Handler
/// \note API identical to osRtxErrorNotify
uint32_t osRtxKernelErrorNotify (uint32_t code, void *object_id) {
  EvrRtxKernelErrorNotify(code, object_id);
  return osRtxErrorNotify(code, object_id);
}


//  ==== Public API ====

/// Initialize the RTOS Kernel.
osStatus_t osKernelInitialize (void) {
  osStatus_t status;

  osRtxKernelBeforeInit();
  EvrRtxKernelInitialize();
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    status = osErrorISR;
  } else {
    status = __svcKernelInitialize();
  }
  return status;
}

///  Get RTOS Kernel Information.
osStatus_t osKernelGetInfo (osVersion_t *version, char *id_buf, uint32_t id_size) {
  osStatus_t status;

  EvrRtxKernelGetInfo(version, id_buf, id_size);
  if (IsException() || IsIrqMasked() || IsPrivileged()) {
    status = svcRtxKernelGetInfo(version, id_buf, id_size);
  } else {
    status =  __svcKernelGetInfo(version, id_buf, id_size);
  }
  return status;
}

/// Get the current RTOS Kernel state.
osKernelState_t osKernelGetState (void) {
  osKernelState_t state;

  if (IsException() || IsIrqMasked() || IsPrivileged()) {
    state = svcRtxKernelGetState();
  } else {
    state =  __svcKernelGetState();
  }
  return state;
}

/// Start the RTOS Kernel scheduler.
osStatus_t osKernelStart (void) {
  osStatus_t status;

  EvrRtxKernelStart();
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    status = osErrorISR;
  } else {
    status = __svcKernelStart();
  }
  return status;
}

/// Lock the RTOS Kernel scheduler.
int32_t osKernelLock (void) {
  int32_t lock;

  EvrRtxKernelLock();
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    lock = (int32_t)osErrorISR;
  } else {
    lock = __svcKernelLock();
  }
  return lock;
}

/// Unlock the RTOS Kernel scheduler.
int32_t osKernelUnlock (void) {
  int32_t lock;

  EvrRtxKernelUnlock();
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    lock = (int32_t)osErrorISR;
  } else {
    lock = __svcKernelUnlock();
  }
  return lock;
}

/// Restore the RTOS Kernel scheduler lock state.
int32_t osKernelRestoreLock (int32_t lock) {
  int32_t lock_new;

  EvrRtxKernelRestoreLock(lock);
  if (IsException() || IsIrqMasked()) {
    if (IsFault() || IsSVCallIrq() || IsPendSvIrq() || IsTickIrq(osRtxInfo.tick_irqn)) {
      lock_new = svcRtxKernelRestoreLock(lock);
    } else {
      EvrRtxKernelError((int32_t)osErrorISR);
      lock_new = (int32_t)osErrorISR;
    }
  } else {
    lock_new   =  __svcKernelRestoreLock(lock);
  }
  return lock_new;
}

/// Suspend the RTOS Kernel scheduler.
uint32_t osKernelSuspend (void) {
  uint32_t ticks;

  EvrRtxKernelSuspend();
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    ticks = 0U;
  } else {
    ticks = __svcKernelSuspend();
  }
  return ticks;
}

/// Resume the RTOS Kernel scheduler.
void osKernelResume (uint32_t sleep_ticks) {

  EvrRtxKernelResume(sleep_ticks);
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
  } else {
    __svcKernelResume(sleep_ticks);
  }
}

#ifdef RTX_SAFETY_CLASS

/// Protect the RTOS Kernel scheduler access.
osStatus_t osKernelProtect (uint32_t safety_class) {
  osStatus_t status;

  EvrRtxKernelProtect(safety_class);
  if (IsException() || IsIrqMasked()) {
    EvrRtxKernelError((int32_t)osErrorISR);
    status = osErrorISR;
  } else {
    status = __svcKernelProtect(safety_class);
  }
  return status;
}

/// Destroy RTOS objects for specified safety classes.
osStatus_t osKernelDestroyClass (uint32_t safety_class, uint32_t mode) {
  osStatus_t status;

  EvrRtxKernelDestroyClass(safety_class, mode);
  if (IsException() || IsIrqMasked()) {
    if (IsTickIrq(osRtxInfo.tick_irqn)) {
      status = svcRtxKernelDestroyClass(safety_class, mode);
    } else {
      EvrRtxKernelError((int32_t)osErrorISR);
      status = osErrorISR;
    }
  } else {
    status   =  __svcKernelDestroyClass(safety_class, mode);
  }
  return status;
}

#endif

/// Get the RTOS kernel tick count.
uint32_t osKernelGetTickCount (void) {
  uint32_t count;

  if (IsException() || IsIrqMasked()) {
    count = svcRtxKernelGetTickCount();
  } else {
    count =  __svcKernelGetTickCount();
  }
  return count;
}

/// Get the RTOS kernel tick frequency.
uint32_t osKernelGetTickFreq (void) {
  uint32_t freq;

  if (IsException() || IsIrqMasked()) {
    freq = svcRtxKernelGetTickFreq();
  } else {
    freq =  __svcKernelGetTickFreq();
  }
  return freq;
}

/// Get the RTOS kernel system timer count.
uint32_t osKernelGetSysTimerCount (void) {
  uint32_t count;

  if (IsException() || IsIrqMasked()) {
    count = svcRtxKernelGetSysTimerCount();
  } else {
    count =  __svcKernelGetSysTimerCount();
  }
  return count;
}

/// Get the RTOS kernel system timer frequency.
uint32_t osKernelGetSysTimerFreq (void) {
  uint32_t freq;

  if (IsException() || IsIrqMasked()) {
    freq = svcRtxKernelGetSysTimerFreq();
  } else {
    freq =  __svcKernelGetSysTimerFreq();
  }
  return freq;
}