score: Add _Watchdog_Nanoseconds_per_tick

Move it from the configuration to a separate variable.

Update #3117.
Update #3182.

cpukit/sapi/include/confdefs.h

@@ -3108,6 +3108,9 @@ extern rtems_initialization_tasks_table Initialization_tasks[];
   const size_t _Thread_Control_add_on_count =
     RTEMS_ARRAY_SIZE( _Thread_Control_add_ons );
 
+  const uint32_t _Watchdog_Nanoseconds_per_tick =
+    1000 * CONFIGURE_MICROSECONDS_PER_TICK;
+
   const uint32_t _Watchdog_Ticks_per_second = _CONFIGURE_TICKS_PER_SECOND;
 
   const uint64_t _Watchdog_Monotonic_max_seconds =
@@ -3167,7 +3170,6 @@ extern rtems_initialization_tasks_table Initialization_tasks[];
     _CONFIGURE_POSIX_KEYS,                     /* POSIX keys are always */
     CONFIGURE_MAXIMUM_POSIX_KEY_VALUE_PAIRS,  /*   enabled */
     CONFIGURE_MICROSECONDS_PER_TICK,          /* microseconds per clock tick */
-    1000 * CONFIGURE_MICROSECONDS_PER_TICK,   /* nanoseconds per clock tick */
     CONFIGURE_TICKS_PER_TIMESLICE,            /* ticks per timeslice quantum */
     CONFIGURE_IDLE_TASK_BODY,                 /* user's IDLE task */
     CONFIGURE_IDLE_TASK_STACK_SIZE,           /* IDLE task stack size */

cpukit/sapi/include/rtems/config.h

@@ -43,6 +43,8 @@ extern "C" {
 #define rtems_resource_maximum_per_allocation(resource) \
   _Objects_Maximum_per_allocation(resource)
 
+#include <rtems/score/watchdog.h>
+
 /*
  *  This is kind of kludgy but it allows targets to totally ignore the
  *  optional APIs like POSIX safely.
@@ -164,14 +166,6 @@ typedef struct {
    */
   uint32_t                       microseconds_per_tick;
 
-  /** 
-   * This field specifies the number of nanoseconds which elapse
-   * between clock ticks.  This value is derived from the
-   * microseconds_per_tick field and provided to avoid calculation at
-   * run-time.
-   */
-  uint32_t                       nanoseconds_per_tick;
-
   /** 
    * This field specifies the number of ticks in each task's timeslice.
    */
@@ -308,7 +302,7 @@ extern const rtems_configuration_table Configuration;
 #define rtems_configuration_get_milliseconds_per_tick() \
         (Configuration.microseconds_per_tick / 1000)
 #define rtems_configuration_get_nanoseconds_per_tick() \
-        (Configuration.nanoseconds_per_tick)
+        (_Watchdog_Nanoseconds_per_tick)
 
 #define rtems_configuration_get_ticks_per_timeslice() \
         (Configuration.ticks_per_timeslice)

cpukit/score/include/rtems/score/watchdog.h

@@ -158,6 +158,14 @@ struct Watchdog_Control {
  */
 extern volatile Watchdog_Interval _Watchdog_Ticks_since_boot;
 
+/**
+ * @brief The watchdog nanoseconds per tick.
+ *
+ * This constant is defined by the application configuration via
+ * <rtems/confdefs.h>.
+ */
+extern const uint32_t _Watchdog_Nanoseconds_per_tick;
+
 /**
  * @brief The watchdog ticks per second.
  *

testsuites/sptests/spwatchdog/init.c

@@ -59,6 +59,7 @@ static void test_watchdog_static_init( void )
 
 static void test_watchdog_config( void )
 {
+  rtems_test_assert( _Watchdog_Nanoseconds_per_tick == 10000000 );
   rtems_test_assert( _Watchdog_Ticks_per_second == 100 );
   rtems_test_assert( _Watchdog_Monotonic_max_seconds == 184467440737095516 );
 }