time-sim: added time operations

They're designed to be used for both the instances, master and slave. This is possible because the new data structure pp_sim_time_instance holding all the information about the time of a single instance is placed inside the ppi arch_data

time-sim: added time operations
They're designed to be used for both the instances, master and slave. This is possible because the new data structure pp_sim_time_instance holding all the information about the time of a single instance is placed inside the ppi arch_data
aea3aa29 · Pietro Fezzardi · Alessandro Rubini · 44e73697 · aea3aa29 · aea3aa29
Commit aea3aa29 authored Nov 27, 2013 by Pietro Fezzardi Committed by Alessandro Rubini Mar 21, 2014
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ppsi-sim.h arch-sim/ppsi-sim.h +32 -0

sim-time.c time-sim/sim-time.c +101 -0

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--- a/arch-sim/ppsi-sim.h
+++ b/arch-sim/ppsi-sim.h
@@ -4,6 +4,22 @@
 * Released to the public domain
 */

+/*
+ * This structure represents a clock abstraction. You can use it to
+ * have different pp_instances with different notions of time.
+ * When you try to get the time the sim_get_time function is performing the
+ * calculations needed to convert the raw data from the "real" clock to the
+ * timescale of the simulated one.
+ * When you set the time you're not actually setting it in the hardware but
+ * only in the parameters in this structure.
+ */
+struct pp_sim_time_instance {
+	int64_t current_ns; // with nsecs it's enough for ~300 years
+	int64_t freq_ppm_real; // drift of the simulated hw clock
+	int64_t freq_ppm_servo; // drift applied from servo to correct the hw
+	// Future parameters can be added
+};
+
 /*
 * This structure holds the lowest timeout of all the state machines in the
 * ppg, namely the master and slave state machines in the simulator. All the
@@ -19,4 +35,20 @@ static inline struct sim_ppg_arch_data *SIM_PPG_ARCH(struct pp_globals *ppg)
 	return (struct sim_ppg_arch_data *)(ppg->arch_data);
 }

+/*
+ * Structure holding parameters and informations restricted to just a single
+ * instance, like timing informations. Infact in the simulator, even if both
+ * master and slave are ppi inside the same ppg, they act like every one of
+ * them had its own clock.
+ * More stuff can be added here in the future if necessary
+ */
+struct sim_ppi_arch_data {
+	struct pp_sim_time_instance time;
+};
+
+static inline struct sim_ppi_arch_data *SIM_PPI_ARCH(struct pp_instance *ppi)
+{
+	return (struct sim_ppi_arch_data *)(ppi->arch_data);
+}
+
 extern void sim_main_loop(struct pp_globals *ppg);
--- a/time-sim/sim-time.c
+++ b/time-sim/sim-time.c
+/*
+ * Copyright (C) 2013 CERN (www.cern.ch)
+ * Author: Pietro Fezzardi (pietrofezzardi@gmail.com)
+ *
+ * Released to the public domain
+ */
+
+/*
+ * Time operations for the simulator, design to be used both for
+ * master and the slave instance.
+ */
+
+#include <time.h>
+#include <errno.h>
+#include <ppsi/ppsi.h>
+#include "../arch-sim/ppsi-sim.h"
+
+static int sim_time_get(struct pp_instance *ppi, TimeInternal *t)
+{
+	struct timespec ts;
+
+	ts.tv_nsec = SIM_PPI_ARCH(ppi)->time.current_ns %
+				(long long)PP_NSEC_PER_SEC;
+	ts.tv_sec = (SIM_PPI_ARCH(ppi)->time.current_ns - ts.tv_nsec) /
+				(long long)PP_NSEC_PER_SEC;
+
+	t->nanoseconds = ts.tv_nsec;
+	t->seconds = ts.tv_sec;
+	t->correct = 1;
+
+	if (!(pp_global_flags & PP_FLAG_NOTIMELOG))
+		pp_diag(ppi, time, 2, "%s: %9li.%09li\n", __func__,
+			(long)t->seconds, (long)t->nanoseconds);
+	return 0;
+}
+
+static int sim_time_set(struct pp_instance *ppi, TimeInternal *t)
+{
+	if (!t) {
+		/* Change the network notion of utc/tai offset */
+		return 0;
+	}
+
+	SIM_PPI_ARCH(ppi)->time.current_ns = t->nanoseconds
+				+ t->seconds * (long long)PP_NSEC_PER_SEC;
+
+	pp_diag(ppi, time, 1, "%s: %9i.%09i\n", __func__,
+			t->seconds, t->nanoseconds);
+	return 0;
+}
+
+static int sim_time_adjust(struct pp_instance *ppi, long offset_ns,
+				long freq_ppm)
+{
+	if (freq_ppm) {
+		if (freq_ppm > PP_ADJ_FREQ_MAX)
+			freq_ppm = PP_ADJ_FREQ_MAX;
+		if (freq_ppm < -PP_ADJ_FREQ_MAX)
+			freq_ppm = -PP_ADJ_FREQ_MAX;
+		SIM_PPI_ARCH(ppi)->time.freq_ppm_servo = freq_ppm;
+	}
+
+	if (offset_ns)
+		SIM_PPI_ARCH(ppi)->time.current_ns += offset_ns;
+
+	pp_diag(ppi, time, 1, "%s: %li %li\n", __func__, offset_ns, freq_ppm);
+	return 0;
+}
+
+static int sim_adjust_freq(struct pp_instance *ppi, long freq_ppm)
+{
+	return sim_time_adjust(ppi, 0, freq_ppm);
+}
+
+static int sim_adjust_offset(struct pp_instance *ppi, long offset_ns)
+{
+	return sim_time_adjust(ppi, offset_ns, 0);
+}
+
+static inline int sim_init_servo(struct pp_instance *ppi)
+{
+	return SIM_PPI_ARCH(ppi)->time.freq_ppm_servo;
+}
+
+static unsigned long sim_calc_timeout(struct pp_instance *ppi, int millisec)
+{
+	unsigned long res;
+
+	res = millisec + SIM_PPI_ARCH(ppi)->time.current_ns / 1000LL / 1000LL;
+	return res ? res : 1;
+}
+
+struct pp_time_operations sim_time_ops = {
+	.get = sim_time_get,
+	.set = sim_time_set,
+	.adjust = sim_time_adjust,
+	.adjust_offset = sim_adjust_offset,
+	.adjust_freq = sim_adjust_freq,
+	.init_servo = sim_init_servo,
+	.calc_timeout = sim_calc_timeout,
+};