libosmo_emb: Implement _gettimeofday() on simplistic 'jiffies' counter.

We simply use the SysTick timer to count at 1KHz and fill a 64bit jiffies
conunter.  This counter is then used to fill tv_sec and tv_usec in the
gettimeofday() implementation.

NOTE: tv_sec will not indicate the seconds since the epoch (Jan 01,
1970), but rather since system startup.  For the existign users,
particularly osmo_timer, this doesn't matter.

Change-Id: I9dbbb730996bde1e7039f790d76d7243739a8419

1 files changed, 13 insertions, 4 deletions

diff --git a/sysmoOCTSIM/libosmo_emb.c b/sysmoOCTSIM/libosmo_emb.c
index 887887d..b100560 100644
--- a/sysmoOCTSIM/libosmo_emb.c
+++ b/sysmoOCTSIM/libosmo_emb.c
@@ -14,16 +14,22 @@ void *g_msgb_ctx;
  ***********************************************************************/
 
 #include <sys/time.h>
+#include "driver_init.h"
+
+volatile uint64_t jiffies;
+
+void SysTick_Handler(void)
+{
+	jiffies++;
+}
 
-/* FIXME: Implement it bsed on jiffies and/or RTC! */
 int _gettimeofday(struct timeval *tv, void *tz)
 {
-	tv->tv_sec = 0;
-	tv->tv_usec = 0;
+	tv->tv_sec = jiffies / 1000;
+	tv->tv_usec = (jiffies % 1000) * 1000;
 	return 0;
 }
 
-
 /***********************************************************************
  * Logging
  ***********************************************************************/
@@ -124,4 +130,7 @@ void libosmo_emb_init(void)
 	stderr_target = log_target_create_stderr_raw();
 	log_add_target(stderr_target);
 	log_set_all_filter(stderr_target, 1);
+
+	/* timer */
+	SysTick_Config(SystemCoreClock / 1000);
 }