diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index f4a378cb66f6..0fa7dd328783 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -1062,16 +1062,11 @@ static struct cs_etm_queue *cs_etm__alloc_queue(void)
 
 static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 			       struct auxtrace_queue *queue,
-			       unsigned int queue_nr, enum cs_etm_format format)
+			       unsigned int queue_nr)
 {
 	struct cs_etm_queue *etmq = queue->priv;
 
-	if (etmq && format != etmq->format) {
-		pr_err("CS_ETM: mixed formatted and unformatted trace not supported\n");
-		return -EINVAL;
-	}
-
-	if (list_empty(&queue->head) || etmq)
+	if (etmq)
 		return 0;
 
 	etmq = cs_etm__alloc_queue();
@@ -1084,7 +1079,6 @@ static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 	etmq->queue_nr = queue_nr;
 	queue->cpu = queue_nr; /* Placeholder, may be reset to -1 in per-thread mode */
 	etmq->offset = 0;
-	etmq->format = format;
 
 	return 0;
 }
@@ -2797,17 +2791,6 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 		if (err)
 			return err;
 
-		/*
-		 * Knowing if the trace is formatted or not requires a lookup of
-		 * the aux record so only works in non-piped mode where data is
-		 * queued in cs_etm__queue_aux_records(). Always assume
-		 * formatted in piped mode (true).
-		 */
-		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
-					  idx, FORMATTED);
-		if (err)
-			return err;
-
 		if (dump_trace)
 			if (auxtrace_buffer__get_data(buffer, fd)) {
 				cs_etm__dump_event(etm->queues.queue_array[idx].priv, buffer);
@@ -2924,7 +2907,6 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 	struct perf_record_auxtrace *auxtrace_event;
 	union perf_event auxtrace_fragment;
 	__u64 aux_offset, aux_size;
-	__u32 idx;
 	enum cs_etm_format format;
 
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
@@ -2991,6 +2973,8 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 
 	if (aux_offset >= auxtrace_event->offset &&
 	    aux_offset + aux_size <= auxtrace_event->offset + auxtrace_event->size) {
+		struct cs_etm_queue *etmq = etm->queues.queue_array[auxtrace_event->idx].priv;
+
 		/*
 		 * If this AUX event was inside this buffer somewhere, create a new auxtrace event
 		 * based on the sizes of the aux event, and queue that fragment.
@@ -3007,11 +2991,14 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 		if (err)
 			return err;
 
-		idx = auxtrace_event->idx;
 		format = (aux_event->flags & PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW) ?
 				UNFORMATTED : FORMATTED;
-
-		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx, format);
+		if (etmq->format != UNSET && format != etmq->format) {
+			pr_err("CS_ETM: mixed formatted and unformatted trace not supported\n");
+			return -EINVAL;
+		}
+		etmq->format = format;
+		return 0;
 	}
 
 	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
@@ -3263,6 +3250,7 @@ static int cs_etm__create_decoders(struct cs_etm_auxtrace *etm)
 		 * Don't create decoders for empty queues, mainly because
 		 * etmq->format is unknown for empty queues.
 		 */
+		assert(empty == (etmq->format == UNSET));
 		if (empty)
 			continue;
 
@@ -3282,10 +3270,10 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	int event_header_size = sizeof(struct perf_event_header);
 	int total_size = auxtrace_info->header.size;
 	int priv_size = 0;
-	int num_cpu;
+	int num_cpu, max_cpu = 0;
 	int err = 0;
 	int aux_hw_id_found;
-	int i, j;
+	int i;
 	u64 *ptr = NULL;
 	u64 **metadata = NULL;
 
@@ -3316,7 +3304,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	 * required by the trace decoder to properly decode the trace due
 	 * to its highly compressed nature.
 	 */
-	for (j = 0; j < num_cpu; j++) {
+	for (int j = 0; j < num_cpu; j++) {
 		if (ptr[i] == __perf_cs_etmv3_magic) {
 			metadata[j] =
 				cs_etm__create_meta_blk(ptr, &i,
@@ -3340,6 +3328,9 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 			err = -ENOMEM;
 			goto err_free_metadata;
 		}
+
+		if ((int) metadata[j][CS_ETM_CPU] > max_cpu)
+			max_cpu = metadata[j][CS_ETM_CPU];
 	}
 
 	/*
@@ -3369,10 +3360,16 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	 */
 	etm->pid_fmt = cs_etm__init_pid_fmt(metadata[0]);
 
-	err = auxtrace_queues__init(&etm->queues);
+	err = auxtrace_queues__init_nr(&etm->queues, max_cpu + 1);
 	if (err)
 		goto err_free_etm;
 
+	for (unsigned int j = 0; j < etm->queues.nr_queues; ++j) {
+		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[j], j);
+		if (err)
+			goto err_free_queues;
+	}
+
 	if (session->itrace_synth_opts->set) {
 		etm->synth_opts = *session->itrace_synth_opts;
 	} else {
@@ -3494,7 +3491,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	zfree(&etm);
 err_free_metadata:
 	/* No need to check @metadata[j], free(NULL) is supported */
-	for (j = 0; j < num_cpu; j++)
+	for (int j = 0; j < num_cpu; j++)
 		zfree(&metadata[j]);
 	zfree(&metadata);
 err_free_traceid_list:
