support UTC/TAI offset

This adds support for the utc/tai offset.
Unix, bare and wrs use UTC in system time and TAI in PTP frames.
WR time is TAI as well, and wrpc-sw passes 0 as offset value when
run as master.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

arch-unix/unix-startup.c

@@ -17,6 +17,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <sys/timex.h>
 
 #include <ppsi/ppsi.h>
 #include "ppsi-unix.h"
@@ -35,6 +36,7 @@ int main(int argc, char **argv)
 {
 	struct pp_globals *ppg;
 	struct pp_instance *ppi;
+	struct timex t;
 	int i;
 
 	setbuf(stdout, NULL);
@@ -55,6 +57,10 @@ int main(int argc, char **argv)
 	if ((!ppg->arch_data) || (!ppg->pp_instances))
 		exit(__LINE__);
 
+	/* Set offset here, so config parsing can override it */
+	if (adjtimex(&t) >= 0)
+		timePropertiesDS.currentUtcOffset = t.tai;
+
 	pp_config_file(ppg, &argc, argv, NULL, "link 0\niface eth0\n"
 		       "proto udp\n" /* mandatory  trailing \n */);
 

arch-wrs/wrs-startup.c

@@ -17,6 +17,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <sys/timex.h>
 
 #include <minipc.h>
 #include <hal_exports.h>
@@ -42,6 +43,7 @@ int main(int argc, char **argv)
 {
 	struct pp_globals *ppg;
 	struct pp_instance *ppi;
+	struct timex t;
 	int i;
 
 	setbuf(stdout, NULL);
@@ -76,6 +78,18 @@ int main(int argc, char **argv)
 	if ((!ppg->arch_data) || (!ppg->pp_instances))
 		exit(__LINE__);
 
+	/* Set offset here, so config parsing can override it */
+	if (adjtimex(&t) >= 0) {
+		int *p;
+		/*
+		 * Our WRS kernel has tai support, but our compiler does not.
+		 * We are 32-bit only, and we know for sure that tai is
+		 * exactly after stbcnt. It's a bad hack, but it works
+		 */
+		p = (int *)(&t.stbcnt) + 1;
+		timePropertiesDS.currentUtcOffset = *p;
+	}
+
 	pp_config_file(ppg, &argc, argv, "/wr/etc/ppsi.conf",
 		       "link 0\niface wr0\n" /* mandatory trailing \n */);
 

lib-bare/bare-startup.c

@@ -38,6 +38,7 @@ int ppsi_main(int argc, char **argv)
 {
 	struct pp_globals *ppg = &ppg_static;
 	struct pp_instance *ppi = &ppi_static; /* no malloc, one instance */
+	struct bare_timex t;
 
 	if (pp_diag_verbosity)
 		pp_printf("ppsi starting. Built on %s\n", __DATE__);
@@ -58,6 +59,9 @@ int ppsi_main(int argc, char **argv)
 
 	ppg->rt_opts = &default_rt_opts;
 
+	if (sys_adjtimex(&t) >= 0)
+		timePropertiesDS.currentUtcOffset = t.tai;
+
 	if (pp_parse_cmdline(ppg, argc, argv) != 0)
 		return -1;
 

proto-standard/bmc.c

@@ -61,6 +61,9 @@ static void s1(struct pp_instance *ppi, MsgHeader *hdr, MsgAnnounce *ann)
 
 	/* Timeproperties DS */
 	prop->timeSource = ann->timeSource;
+	if (prop->currentUtcOffset != ann->currentUtcOffset)
+		pp_diag(ppi, bmc, 1, "New UTC offset: %i\n",
+			ann->currentUtcOffset);
 	prop->currentUtcOffset = ann->currentUtcOffset;
 
 	/* FIXME: can't we just copy the bit keeping values? */

time-bare/bare-time.c

@@ -16,7 +16,8 @@ static int bare_time_get(struct pp_instance *ppi, TimeInternal *t)
 		pp_error("%s:", __func__);
 		sys_exit(1);
 	}
-	t->seconds = tv.tv_sec;
+	/* TAI = UTC + 34 */
+	t->seconds = tv.tv_sec + DSPRO(ppi)->currentUtcOffset;
 	t->nanoseconds = tv.tv_usec * 1000;
 	if (!(pp_global_flags & PP_FLAG_NOTIMELOG))
 		pp_diag(ppi, time, 2, "%s: %9li.%06li\n", __func__,
@@ -28,7 +29,8 @@ static int bare_time_set(struct pp_instance *ppi, TimeInternal *t)
 {
 	struct bare_timeval tv;
 
-	tv.tv_sec = t->seconds;
+	/* UTC = TAI - 34 */
+	tv.tv_sec = t->seconds - DSPRO(ppi)->currentUtcOffset;
 	tv.tv_usec = t->nanoseconds / 1000;
 
 	if (sys_settimeofday(&tv, NULL) < 0) {

time-unix/unix-time.c

@@ -24,7 +24,8 @@ static int unix_time_get(struct pp_instance *ppi, TimeInternal *t)
 	struct timespec tp;
 	if (clock_gettime(CLOCK_REALTIME, &tp) < 0)
 		clock_fatal_error("clock_gettime");
-	t->seconds = tp.tv_sec;
+	/* TAI = UTC + 34 */
+	t->seconds = tp.tv_sec + DSPRO(ppi)->currentUtcOffset;
 	t->nanoseconds = tp.tv_nsec;
 	t->correct = 1;
 	if (!(pp_global_flags & PP_FLAG_NOTIMELOG))
@@ -37,7 +38,8 @@ static int32_t unix_time_set(struct pp_instance *ppi, TimeInternal *t)
 {
 	struct timespec tp;
 
-	tp.tv_sec = t->seconds;
+	/* UTC = TAI - 34 */
+	tp.tv_sec = t->seconds - DSPRO(ppi)->currentUtcOffset;
 	tp.tv_nsec = t->nanoseconds;
 	if (clock_settime(CLOCK_REALTIME, &tp) < 0)
 		clock_fatal_error("clock_settime");