Merge pull request #3347 from benoit-canet/timer

native: timer: synchronize HWTIMER_SPIN_BARRIER with native timer min resolution

cpu/native/include/hwtimer_cpu.h

@@ -14,6 +14,8 @@
  * @}
  */
 
+#include "periph_conf.h"
+
 #ifndef HWTIMER_CPU_H_
 #define HWTIMER_CPU_H_
 
@@ -24,7 +26,7 @@ extern "C" {
 #define HWTIMER_MAXTIMERS 1
 #define HWTIMER_SPEED 1000000
 #define HWTIMER_MAXTICKS (0xFFFFFFFF)
-#define HWTIMER_SPIN_BARRIER 20
+#define HWTIMER_SPIN_BARRIER NATIVE_TIMER_MIN_RES
 
 #ifdef __cplusplus
 }

cpu/native/include/periph_conf.h

@@ -20,6 +20,13 @@
  extern "C" {
 #endif
 
+/**
+ * @name hardware timer clock skew avoidance
+ * @{
+ */
+#define NATIVE_TIMER_MIN_RES 200
+/** @} */
+
 /**
  * @name Random Number Generator configuration
  * @{

cpu/native/periph/timer.c

@@ -46,8 +46,6 @@
 
 #define NATIVE_TIMER_SPEED 1000000
 
-#define NATIVE_TIMER_MIN_RES 200
-
 static unsigned long time_null;
 
 static void (*_callback)(int);

tests/hwtimer_spin/main.c

@@ -32,7 +32,7 @@ int main(void)
             " this test was successful.");
     puts("If you do not see that message, something went wrong.\n");
 
-    for (unsigned long r = 10000; r > 0; r--) {
+    for (unsigned long r = 1000; r > 0; r--) {
         for (unsigned long i = HWTIMER_SPIN_BARRIER; i > 0; i--) {
             hwtimer_wait(i);
         }

tests/hwtimer_wait/main.c

@@ -29,7 +29,7 @@ int main(void)
     puts("This is a regression test for a race condition in hwtimer_wait.");
     puts("When the race condition is hit, the timer will wait for a very very long time.");
 
-    long iterations = 10000;
+    long iterations = 1000;
     long start_duration = (HWTIMER_SPIN_BARRIER + 1) << 5;
     long duration = iterations * start_duration * 2L;