dsp: Replace wall clock for KPI calculations

Replace clock reference from wall clock to MONOTONIC.
This is to avoid getting impacted when system time is
set backwards or forwards (either through network or manually).

Change-Id: I98625b033f689002c9334633cf3944608d5a77d3
Signed-off-by: Md Mansoor Ahmed <[email protected]>

dsp/q6asm.c

@@ -389,6 +389,33 @@ static const struct file_operations audio_input_latency_debug_fops = {
 	.write = audio_input_latency_dbgfs_write
 };
 
+/*
+ * get_monotonic_timeval -
+ *       This method returns a structure in timeval
+ *       format (sec,microsec) by using ktime kernel
+ *       API to get time in nano secs and then converts
+ *       it to timeval format
+ *
+ * ktime_get [nsec]-> ktime_to_timespec [sec,nsec]-> timeval[sec,usec]
+ *
+ * Returns struct timeval
+*/
+static struct timeval get_monotonic_timeval(void)
+{
+	static struct timeval out_tval;
+
+	/* Get time from monotonic clock in nanoseconds */
+	ktime_t kTimeNsec = ktime_get();
+
+	/* Convert it to timespec format and later to timeval as expected by audio HAL */
+	struct timespec temp_tspec = ktime_to_timespec(kTimeNsec);
+
+	/* Time returned above is in sec,nanosec format, needs to convert to sec,microsec */
+	out_tval.tv_usec = temp_tspec.tv_nsec/1000;
+	out_tval.tv_sec = temp_tspec.tv_sec;
+	return out_tval;
+}
+
 static void config_debug_fs_write_cb(void)
 {
 	if (out_enable_flag) {
@@ -396,7 +423,7 @@ static void config_debug_fs_write_cb(void)
 		 * out_cold_index
 		 */
 		if (out_cold_index != 1) {
-			do_gettimeofday(&out_cold_tv);
+			out_cold_tv = get_monotonic_timeval();
 			pr_debug("COLD: apr_send_pkt at %ld sec %ld microsec\n",
 				out_cold_tv.tv_sec,
 				out_cold_tv.tv_usec);
@@ -421,7 +448,7 @@ static void config_debug_fs_read_cb(void)
 		 * Hence continuous input latency
 		 */
 		if (in_cont_index == 7) {
-			do_gettimeofday(&in_cont_tv);
+			in_cont_tv = get_monotonic_timeval();
 			pr_info("%s: read buffer at %ld sec %ld microsec\n",
 				__func__,
 				in_cont_tv.tv_sec, in_cont_tv.tv_usec);
@@ -438,7 +465,7 @@ static void config_debug_fs_reset_index(void)
 static void config_debug_fs_run(void)
 {
 	if (out_enable_flag) {
-		do_gettimeofday(&out_cold_tv);
+		out_cold_tv = get_monotonic_timeval();
 		pr_debug("%s: COLD apr_send_pkt at %ld sec %ld microsec\n",
 			__func__, out_cold_tv.tv_sec, out_cold_tv.tv_usec);
 	}
@@ -453,7 +480,7 @@ static void config_debug_fs_write(struct audio_buffer *ab)
 		 */
 		if ((strcmp(((char *)ab->data), zero_pattern)) &&
 		(!strcmp(((char *)ab->data + 2), zero_pattern))) {
-			do_gettimeofday(&out_warm_tv);
+			out_warm_tv = get_monotonic_timeval();
 			pr_debug("%s: WARM:apr_send_pkt at %ld sec %ld microsec\n",
 			 __func__,
 			 out_warm_tv.tv_sec,
@@ -465,7 +492,7 @@ static void config_debug_fs_write(struct audio_buffer *ab)
 		 */
 		else if ((!strcmp(((char *)ab->data), zero_pattern))
 		&& (strcmp(((char *)ab->data + 2), zero_pattern))) {
-			do_gettimeofday(&out_cont_tv);
+			out_cont_tv = get_monotonic_timeval();
 			pr_debug("%s: CONT:apr_send_pkt at %ld sec %ld microsec\n",
 			__func__,
 			out_cont_tv.tv_sec,