[PATCH 10/10] ALSA: firewire-lib: use sequence of syt offset and data block on pool in AMDTP domain

Takashi Sakamoto o-takashi at sakamocchi.jp
Fri May 8 06:36:35 CEST 2020


In previous commit, the sequence of syt offset and the number of data
blocks per packet is calculated for pool in AMDTP domain structure in
advance of processing outgoing packets.

This commit uses the sequence for outgoing packet processing to obsolete
per-stream processing of the sequence.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/amdtp-stream.c | 56 +++++++++++++----------------------
 sound/firewire/amdtp-stream.h |  4 ---
 2 files changed, 20 insertions(+), 40 deletions(-)

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index a2af598e9b9a..f8586f75441d 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -747,34 +747,30 @@ static unsigned int compute_syt(unsigned int syt_offset, unsigned int cycle,
 	return syt & CIP_SYT_MASK;
 }
 
-static void generate_ideal_pkt_descs(struct amdtp_stream *s,
-				     struct pkt_desc *descs,
-				     const __be32 *ctx_header,
-				     unsigned int packets)
+static void generate_pkt_descs(struct amdtp_stream *s, struct pkt_desc *descs,
+			       const __be32 *ctx_header, unsigned int packets,
+			       const struct seq_desc *seq_descs,
+			       unsigned int seq_size)
 {
 	unsigned int dbc = s->data_block_counter;
+	unsigned int seq_index = s->ctx_data.rx.seq_index;
 	int i;
 
 	for (i = 0; i < packets; ++i) {
 		struct pkt_desc *desc = descs + i;
 		unsigned int index = (s->packet_index + i) % s->queue_size;
-		unsigned int syt_offset;
+		const struct seq_desc *seq = seq_descs + seq_index;
+		unsigned int syt;
 
 		desc->cycle = compute_it_cycle(*ctx_header, s->queue_size);
-		syt_offset = calculate_syt_offset(
-				&s->ctx_data.rx.last_syt_offset,
-				&s->ctx_data.rx.syt_offset_state, s->sfc);
-		if (syt_offset != CIP_SYT_NO_INFO) {
-			desc->syt = compute_syt(syt_offset, desc->cycle,
-						s->ctx_data.rx.transfer_delay);
-		} else {
-			desc->syt = syt_offset;
+
+		syt = seq->syt_offset;
+		if (syt != CIP_SYT_NO_INFO) {
+			syt = compute_syt(syt, desc->cycle,
+					  s->ctx_data.rx.transfer_delay);
 		}
-		desc->data_blocks =
-			calculate_data_blocks(&s->ctx_data.rx.data_block_state,
-					      !!(s->flags & CIP_BLOCKING),
-					      desc->syt == CIP_SYT_NO_INFO,
-					      s->syt_interval, s->sfc);
+		desc->syt = syt;
+		desc->data_blocks = seq->data_blocks;
 
 		if (s->flags & CIP_DBC_IS_END_EVENT)
 			dbc = (dbc + desc->data_blocks) & 0xff;
@@ -786,10 +782,13 @@ static void generate_ideal_pkt_descs(struct amdtp_stream *s,
 
 		desc->ctx_payload = s->buffer.packets[index].buffer;
 
+		seq_index = (seq_index + 1) % seq_size;
+
 		++ctx_header;
 	}
 
 	s->data_block_counter = dbc;
+	s->ctx_data.rx.seq_index = seq_index;
 }
 
 static inline void cancel_stream(struct amdtp_stream *s)
@@ -818,6 +817,7 @@ static void out_stream_callback(struct fw_iso_context *context, u32 tstamp,
 				void *private_data)
 {
 	struct amdtp_stream *s = private_data;
+	const struct amdtp_domain *d = s->domain;
 	const __be32 *ctx_header = header;
 	unsigned int events_per_period = s->ctx_data.rx.events_per_period;
 	unsigned int event_count = s->ctx_data.rx.event_count;
@@ -830,7 +830,8 @@ static void out_stream_callback(struct fw_iso_context *context, u32 tstamp,
 	// Calculate the number of packets in buffer and check XRUN.
 	packets = header_length / sizeof(*ctx_header);
 
-	generate_ideal_pkt_descs(s, s->pkt_descs, ctx_header, packets);
+	generate_pkt_descs(s, s->pkt_descs, ctx_header, packets, d->seq_descs,
+			   d->seq_size);
 
 	process_ctx_payloads(s, s->pkt_descs, packets);
 
@@ -1037,18 +1038,6 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
 			      int start_cycle, unsigned int queue_size,
 			      unsigned int idle_irq_interval)
 {
-	static const struct {
-		unsigned int data_block;
-		unsigned int syt_offset;
-	} *entry, initial_state[] = {
-		[CIP_SFC_32000]  = {  4, 3072 },
-		[CIP_SFC_48000]  = {  6, 1024 },
-		[CIP_SFC_96000]  = { 12, 1024 },
-		[CIP_SFC_192000] = { 24, 1024 },
-		[CIP_SFC_44100]  = {  0,   67 },
-		[CIP_SFC_88200]  = {  0,   67 },
-		[CIP_SFC_176400] = {  0,   67 },
-	};
 	bool is_irq_target = (s == s->domain->irq_target);
 	unsigned int ctx_header_size;
 	unsigned int max_ctx_payload_size;
@@ -1072,12 +1061,7 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
 
 		s->data_block_counter = UINT_MAX;
 	} else {
-		entry = &initial_state[s->sfc];
-
 		s->data_block_counter = 0;
-		s->ctx_data.rx.data_block_state = entry->data_block;
-		s->ctx_data.rx.syt_offset_state = entry->syt_offset;
-		s->ctx_data.rx.last_syt_offset = TICKS_PER_CYCLE;
 	}
 
 	/* initialize packet buffer */
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 11cff4cafd90..703b710aaf7f 100644
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -140,10 +140,6 @@ struct amdtp_stream {
 			unsigned int transfer_delay;
 			unsigned int seq_index;
 
-			unsigned int data_block_state;
-			unsigned int last_syt_offset;
-			unsigned int syt_offset_state;
-
 			// To generate CIP header.
 			unsigned int fdf;
 			int syt_override;
-- 
2.25.1



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