ALSA: firewire-lib: extend tracepoints event including CYCLE_TIME of 1394 OHCI

A commit baa914cd81f5 ("firewire: add kernel API to access CYCLE_TIME
register") allow unit drivers to read CYCLE_TIME of 1394 OHCI controller.
The value expresses monotonic time with 42.195 Mhz resolution and wrapping
around every 128 seconds. The controller uses the time to govern
isochronous cycle.

This commit extends tracepoints event including the value so that event
parser can compute gap between current isochronous cycle and the latest
isochronous cycle in which packet is processed (in IR context) or scheduled
(in IT context). It loses backward compatibility to former format of the
tracepoints event.

Signed-off-by: Takashi Sakamoto <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/firewire/amdtp-stream-trace.h

···
 #include <linux/tracepoint.h>
 
 TRACE_EVENT(amdtp_packet,
-	TP_PROTO(const struct amdtp_stream *s, u32 cycles, const __be32 *cip_header, unsigned int payload_length, unsigned int data_blocks, unsigned int data_block_counter, unsigned int packet_index, unsigned int index),
-	TP_ARGS(s, cycles, cip_header, payload_length, data_blocks, data_block_counter, packet_index, index),
+	TP_PROTO(const struct amdtp_stream *s, u32 cycles, const __be32 *cip_header, unsigned int payload_length, unsigned int data_blocks, unsigned int data_block_counter, unsigned int packet_index, unsigned int index, u32 curr_cycle_time),
+	TP_ARGS(s, cycles, cip_header, payload_length, data_blocks, data_block_counter, packet_index, index, curr_cycle_time),
 	TP_STRUCT__entry(
+		__field(unsigned int, cycle_time)
 		__field(unsigned int, second)
 		__field(unsigned int, cycle)
 		__field(int, channel)
···
 		__field(unsigned int, index)
 	),
 	TP_fast_assign(
+		__entry->cycle_time = curr_cycle_time;
 		__entry->second = cycles / CYCLES_PER_SECOND;
 		__entry->cycle = cycles % CYCLES_PER_SECOND;
 		__entry->channel = s->context->channel;
···
 		__entry->index = index;
 	),
 	TP_printk(
-		"%02u %04u %04x %04x %02d %03u %02u %03u %02u %01u %02u %s",
+		"%08x %02u %04u %04x %04x %02d %03u %02u %03u %02u %01u %02u %s",
+		__entry->cycle_time,
 		__entry->second,
 		__entry->cycle,
 		__entry->src,

sound/firewire/amdtp-stream.c

···
 				struct fw_iso_packet *params, unsigned int header_length,
 				unsigned int data_blocks,
 				unsigned int data_block_counter,
-				unsigned int syt, unsigned int index)
+				unsigned int syt, unsigned int index, u32 curr_cycle_time)
 {
 	unsigned int payload_length;
 	__be32 *cip_header;
···
 	}
 
 	trace_amdtp_packet(s, cycle, cip_header, payload_length + header_length, data_blocks,
-			   data_block_counter, s->packet_index, index);
+			   data_block_counter, s->packet_index, index, curr_cycle_time);
 }
 
 static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
···
 			       const __be32 *ctx_header,
 			       unsigned int *data_blocks,
 			       unsigned int *data_block_counter,
-			       unsigned int *syt, unsigned int packet_index, unsigned int index)
+			       unsigned int *syt, unsigned int packet_index, unsigned int index,
+			       u32 curr_cycle_time)
 {
 	unsigned int payload_length;
 	const __be32 *cip_header;
···
 	}
 
 	trace_amdtp_packet(s, cycle, cip_header, payload_length, *data_blocks,
-			   *data_block_counter, packet_index, index);
+			   *data_block_counter, packet_index, index, curr_cycle_time);
 
 	return 0;
 }
···
 	unsigned int dbc = s->data_block_counter;
 	unsigned int packet_index = s->packet_index;
 	unsigned int queue_size = s->queue_size;
+	u32 curr_cycle_time;
 	int i;
 	int err;
+
+	if (trace_amdtp_packet_enabled())
+		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
 
 	*desc_count = 0;
 	for (i = 0; i < packet_count; ++i) {
···
 		}
 
 		err = parse_ir_ctx_header(s, cycle, ctx_header, &data_blocks, &dbc, &syt,
-					  packet_index, i);
+					  packet_index, i, curr_cycle_time);
 		if (err < 0)
 			return err;
 
···
 	struct pkt_desc *desc = s->packet_descs_cursor;
 	unsigned int pkt_header_length;
 	unsigned int packets;
+	u32 curr_cycle_time;
 	bool need_hw_irq;
 	int i;
 
···
 		need_hw_irq = false;
 	}
 
+	if (trace_amdtp_packet_enabled())
+		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
+
 	for (i = 0; i < packets; ++i) {
 		struct {
 			struct fw_iso_packet params;
···
 
 		build_it_pkt_header(s, desc->cycle, &template.params, pkt_header_length,
 				    desc->data_blocks, desc->data_block_counter,
-				    desc->syt, i);
+				    desc->syt, i, curr_cycle_time);
 
 		if (s == s->domain->irq_target) {
 			event_count += desc->data_blocks;