Add frequency to CTFTmfTrace properties

The frequency of the CtfTmfTrace is currently exposed in an indirect way using cyclesToNanos(). But sometimes there is the need to get direct frequency in trace properties. This commit added public methods to get the direct frequency and added them to the properties of the trace.

[Added] frequency in getProperties() in CTFTmfTrace
[Added] public method to get frequency in CTFClock and CTFTrace

ctf/org.eclipse.tracecompass.ctf.core/src/org/eclipse/tracecompass/ctf/core/event/CTFClock.java

@@ -159,4 +159,10 @@ public boolean isClockScaled() {
         return fIsScaled;
     }
 
+    /**
+     * @return the frequency in Hz
+     */
+    public long getFrequency() {
+        return ((Long) getProperty(FREQ));
+    }
 }

ctf/org.eclipse.tracecompass.ctf.core/src/org/eclipse/tracecompass/ctf/core/trace/CTFTrace.java

@@ -832,6 +832,18 @@ public final long getOffset() {
         return fSingleClock.getClockOffset();
     }
 
+    /**
+     * Gets the frequency
+     *
+     * @return the frequency
+     */
+    public final long getFrequency() {
+        if (getClock() == null) {
+            return 0;
+        }
+        return fSingleClock.getFrequency();
+    }
+
     /**
      * Gets the time scale in nanoseconds/cycle
      *

ctf/org.eclipse.tracecompass.tmf.ctf.core/src/org/eclipse/tracecompass/tmf/ctf/core/trace/CtfTmfTrace.java

@@ -115,6 +115,7 @@ public class CtfTmfTrace extends TmfTrace
      * @since 1.2
      */
     public static final String CLOCK_OFFSET = "clock_offset"; //$NON-NLS-1$
+    public static final String CLOCK_FREQUENCY = "frequency"; //$NON-NLS-1$
 
     /**
      * Default cache size for CTF traces
@@ -585,6 +586,7 @@ public Map<String, String> getProperties() {
         }
         properties.putAll(trace.getEnvironment());
         properties.put(CLOCK_OFFSET, Long.toUnsignedString(trace.getOffset()));
+        properties.put(CLOCK_FREQUENCY, Long.toUnsignedString(trace.getFrequency()));
         properties.put(Messages.CtfTmfTrace_HostID, getHostId());
         return properties;
     }