diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 32818bd7cd17..f09004c4ba44 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -103,6 +103,7 @@ struct cs_etm_queue {
 	struct auxtrace_buffer *buffer;
 	unsigned int queue_nr;
 	u8 pending_timestamp_chan_id;
+	bool formatted;
 	u64 offset;
 	const unsigned char *buf;
 	size_t buf_len, buf_used;
@@ -738,8 +739,7 @@ static int cs_etm__init_trace_params(struct cs_etm_trace_params *t_params,
 
 static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
 				       struct cs_etm_queue *etmq,
-				       enum cs_etm_decoder_operation mode,
-				       bool formatted)
+				       enum cs_etm_decoder_operation mode)
 {
 	int ret = -EINVAL;
 
@@ -749,7 +749,7 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
 	d_params->packet_printer = cs_etm__packet_dump;
 	d_params->operation = mode;
 	d_params->data = etmq;
-	d_params->formatted = formatted;
+	d_params->formatted = etmq->formatted;
 	d_params->fsyncs = false;
 	d_params->hsyncs = false;
 	d_params->frame_aligned = true;
@@ -1041,81 +1041,34 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
 	return ret;
 }
 
-static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
-						bool formatted, int sample_cpu)
+static struct cs_etm_queue *cs_etm__alloc_queue(void)
 {
-	struct cs_etm_decoder_params d_params;
-	struct cs_etm_trace_params  *t_params = NULL;
-	struct cs_etm_queue *etmq;
-	/*
-	 * Each queue can only contain data from one CPU when unformatted, so only one decoder is
-	 * needed.
-	 */
-	int decoders = formatted ? etm->num_cpu : 1;
-
-	etmq = zalloc(sizeof(*etmq));
+	struct cs_etm_queue *etmq = zalloc(sizeof(*etmq));
 	if (!etmq)
 		return NULL;
 
 	etmq->traceid_queues_list = intlist__new(NULL);
 	if (!etmq->traceid_queues_list)
-		goto out_free;
-
-	/* Use metadata to fill in trace parameters for trace decoder */
-	t_params = zalloc(sizeof(*t_params) * decoders);
+		free(etmq);
 
-	if (!t_params)
-		goto out_free;
-
-	if (cs_etm__init_trace_params(t_params, etm, formatted, sample_cpu, decoders))
-		goto out_free;
-
-	/* Set decoder parameters to decode trace packets */
-	if (cs_etm__init_decoder_params(&d_params, etmq,
-					dump_trace ? CS_ETM_OPERATION_PRINT :
-						     CS_ETM_OPERATION_DECODE,
-					formatted))
-		goto out_free;
-
-	etmq->decoder = cs_etm_decoder__new(decoders, &d_params,
-					    t_params);
-
-	if (!etmq->decoder)
-		goto out_free;
-
-	/*
-	 * Register a function to handle all memory accesses required by
-	 * the trace decoder library.
-	 */
-	if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
-					      0x0L, ((u64) -1L),
-					      cs_etm__mem_access))
-		goto out_free_decoder;
-
-	zfree(&t_params);
 	return etmq;
-
-out_free_decoder:
-	cs_etm_decoder__free(etmq->decoder);
-out_free:
-	intlist__delete(etmq->traceid_queues_list);
-	free(etmq);
-
-	return NULL;
 }
 
 static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 			       struct auxtrace_queue *queue,
-			       unsigned int queue_nr,
-			       bool formatted,
-			       int sample_cpu)
+			       unsigned int queue_nr, bool formatted)
 {
 	struct cs_etm_queue *etmq = queue->priv;
 
+	if (etmq && formatted != etmq->formatted) {
+		pr_err("CS_ETM: mixed formatted and unformatted trace not supported\n");
+		return -EINVAL;
+	}
+
 	if (list_empty(&queue->head) || etmq)
 		return 0;
 
-	etmq = cs_etm__alloc_queue(etm, formatted, sample_cpu);
+	etmq = cs_etm__alloc_queue();
 
 	if (!etmq)
 		return -ENOMEM;
@@ -1123,7 +1076,9 @@ static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 	queue->priv = etmq;
 	etmq->etm = etm;
 	etmq->queue_nr = queue_nr;
+	queue->cpu = queue_nr; /* Placeholder, may be reset to -1 in per-thread mode */
 	etmq->offset = 0;
+	etmq->formatted = formatted;
 
 	return 0;
 }
@@ -2843,7 +2798,7 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,
 		 * formatted in piped mode (true).
 		 */
 		err = cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
-					  idx, true, -1);
+					  idx, true);
 		if (err)
 			return err;
 
@@ -3048,8 +3003,8 @@ static int cs_etm__queue_aux_fragment(struct perf_session *session, off_t file_o
 
 		idx = auxtrace_event->idx;
 		formatted = !(aux_event->flags & PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
-		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx],
-					   idx, formatted, sample->cpu);
+
+		return cs_etm__setup_queue(etm, &etm->queues.queue_array[idx], idx, formatted);
 	}
 
 	/* Wasn't inside this buffer, but there were no parse errors. 1 == 'not found' */
@@ -3233,6 +3188,84 @@ static int cs_etm__clear_unused_trace_ids_metadata(int num_cpu, u64 **metadata)
 	return 0;
 }
 
+/*
+ * Use the data gathered by the peeks for HW_ID (trace ID mappings) and AUX
+ * (formatted or not) packets to create the decoders.
+ */
+static int cs_etm__create_queue_decoders(struct cs_etm_queue *etmq)
+{
+	struct cs_etm_decoder_params d_params;
+
+	/*
+	 * Each queue can only contain data from one CPU when unformatted, so only one decoder is
+	 * needed.
+	 */
+	int decoders = etmq->formatted ? etmq->etm->num_cpu : 1;
+
+	/* Use metadata to fill in trace parameters for trace decoder */
+	struct cs_etm_trace_params  *t_params = zalloc(sizeof(*t_params) * decoders);
+
+	if (!t_params)
+		goto out_free;
+
+	if (cs_etm__init_trace_params(t_params, etmq->etm, etmq->formatted,
+				      etmq->queue_nr, decoders))
+		goto out_free;
+
+	/* Set decoder parameters to decode trace packets */
+	if (cs_etm__init_decoder_params(&d_params, etmq,
+					dump_trace ? CS_ETM_OPERATION_PRINT :
+						     CS_ETM_OPERATION_DECODE))
+		goto out_free;
+
+	etmq->decoder = cs_etm_decoder__new(decoders, &d_params,
+					    t_params);
+
+	if (!etmq->decoder)
+		goto out_free;
+
+	/*
+	 * Register a function to handle all memory accesses required by
+	 * the trace decoder library.
+	 */
+	if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
+					      0x0L, ((u64) -1L),
+					      cs_etm__mem_access))
+		goto out_free_decoder;
+
+	zfree(&t_params);
+	return 0;
+
+out_free_decoder:
+	cs_etm_decoder__free(etmq->decoder);
+out_free:
+	zfree(&t_params);
+	return -EINVAL;
+}
+
+static int cs_etm__create_decoders(struct cs_etm_auxtrace *etm)
+{
+	struct auxtrace_queues *queues = &etm->queues;
+
+	for (unsigned int i = 0; i < queues->nr_queues; i++) {
+		bool empty = list_empty(&queues->queue_array[i].head);
+		struct cs_etm_queue *etmq = queues->queue_array[i].priv;
+		int ret;
+
+		/*
+		 * Don't create decoders for empty queues, mainly because
+		 * etmq->formatted is unknown for empty queues.
+		 */
+		if (empty)
+			continue;
+
+		ret = cs_etm__create_queue_decoders(etmq);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
 int cs_etm__process_auxtrace_info_full(union perf_event *event,
 				       struct perf_session *session)
 {
@@ -3396,6 +3429,10 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	if (err)
 		goto err_free_queues;
 
+	err = cs_etm__queue_aux_records(session);
+	if (err)
+		goto err_free_queues;
+
 	/*
 	 * Map Trace ID values to CPU metadata.
 	 *
@@ -3418,7 +3455,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	 * flags if present.
 	 */
 
-	/* first scan for AUX_OUTPUT_HW_ID records to map trace ID values to CPU metadata */
+	/* Scan for AUX_OUTPUT_HW_ID records to map trace ID values to CPU metadata */
 	aux_hw_id_found = 0;
 	err = perf_session__peek_events(session, session->header.data_offset,
 					session->header.data_size,
@@ -3436,7 +3473,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
 	if (err)
 		goto err_free_queues;
 
-	err = cs_etm__queue_aux_records(session);
+	err = cs_etm__create_decoders(etm);
 	if (err)
 		goto err_free_queues;
 
