Use shared event queue for timer

Don't create our own timer thread - use the shared event queue.

Author: kjbracey

features/FEATURE_COMMON_PAL/nanostack-hal-mbed-cmsis-rtos/arm_hal_timer.cpp

@@ -4,48 +4,23 @@
 
 // Include before mbed.h to properly get UINT*_C()
 #include "ns_types.h"
+
 #include "mbed.h"
-#include "cmsis_os2.h"
-#include "rtx_os.h"
 #include "platform/arm_hal_timer.h"
 #include "platform/arm_hal_interrupt.h"
 #include <mbed_assert.h>
 
-static osThreadId_t timer_thread_id;
-static uint64_t timer_thread_stk[2048/sizeof(uint64_t)];
-static osRtxThread_t timer_thread_tcb;
-
 static Timer timer;
 static Timeout timeout;
+static EventQueue *equeue;
 static uint32_t due;
 static void (*arm_hal_callback)(void);
 
-static void timer_thread(void *arg)
-{
-    (void)arg;
-    for (;;) {
-        osThreadFlagsWait(1, osFlagsWaitAny, osWaitForever);
-        // !!! We don't do our own enter/exit critical - we rely on callback
-        // doing it (ns_timer_interrupt_handler does)
-        //platform_enter_critical();
-        arm_hal_callback();
-        //platform_exit_critical();
-    }
-}
-
 // Called once at boot
 void platform_timer_enable(void)
 {
-    static osThreadAttr_t timer_thread_attr = {0};
-    timer_thread_attr.name = "pal_timer_thread";
-    timer_thread_attr.stack_mem  = &timer_thread_stk[0];
-    timer_thread_attr.cb_mem  = &timer_thread_tcb;
-    timer_thread_attr.stack_size = sizeof(timer_thread_stk);
-    timer_thread_attr.cb_size = sizeof(timer_thread_tcb);
-    timer_thread_attr.priority = osPriorityRealtime;
-    timer_thread_id = osThreadNew(timer_thread, NULL, &timer_thread_attr);
-    MBED_ASSERT(timer_thread_id != NULL);
-    timer.start();
+    equeue = mbed_highprio_event_queue();
+    MBED_ASSERT(equeue != NULL);
 }
 
 // Actually cancels a timer, not the opposite of enable
@@ -63,7 +38,7 @@ void platform_timer_set_cb(void (*new_fp)(void))
 static void timer_callback(void)
 {
     due = 0;
-    osThreadFlagsSet(timer_thread_id, 1);
+    equeue->call(arm_hal_callback);
 }
 
 // This is called from inside platform_enter_critical - IRQs can't happen