diff mbox series

[1/3] ALSA: firewire-lib: drop initial NODATA packets or empty packets

Message ID 20210523124114.272134-2-o-takashi@sakamocchi.jp (mailing list archive)
State Superseded
Headers show
Series ALSA: firewire-lib: drop initial NODATA packets or empty packets | expand

Commit Message

Takashi Sakamoto May 23, 2021, 12:41 p.m. UTC 
The devices based on BeBoB ASICs or the devices in Tascam FireWire
series transfer a batch of NODATA packet or empty packet in initial step
of streaming. To avoid processing them, current implementation uses an
option to skip processing content of tx packet during some initial
cycles. However, the hard-coded number is not enough useful.

This commit drops content of packets till the packet includes any event.
The function of option is to skip processing content of tx packet with
any event after dropping.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 sound/firewire/amdtp-stream.c | 130 +++++++++++++++++++++++++---------
 sound/firewire/amdtp-stream.h |   3 +
 2 files changed, 100 insertions(+), 33 deletions(-)

Comments

kernel test robot May 23, 2021, 2:15 p.m. UTC | #1 
Hi Takashi,

I love your patch! Perhaps something to improve:

[auto build test WARNING on sound/for-next]
[cannot apply to v5.13-rc2 next-20210521]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Takashi-Sakamoto/ALSA-firewire-lib-drop-initial-NODATA-packets-or-empty-packets/20210523-204607
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git for-next
config: s390-allyesconfig (attached as .config)
compiler: s390-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/a1c11b8ba891b02a7669df5e99ea3f407ee3efb7
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Takashi-Sakamoto/ALSA-firewire-lib-drop-initial-NODATA-packets-or-empty-packets/20210523-204607
        git checkout a1c11b8ba891b02a7669df5e99ea3f407ee3efb7
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   sound/firewire/amdtp-stream.c: In function 'amdtp_stream_first_callback':
>> sound/firewire/amdtp-stream.c:1376:6: warning: variable 'cycle' set but not used [-Wunused-but-set-variable]
    1376 |  u32 cycle;
         |      ^~~~~


vim +/cycle +1376 sound/firewire/amdtp-stream.c

9b1fcd9bf80206 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1367  
60dd49298ec580 sound/firewire/amdtp-stream.c Takashi Sakamoto 2019-10-18  1368  // this is executed one time.
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1369  static void amdtp_stream_first_callback(struct fw_iso_context *context,
73fc7f080105b1 sound/firewire/amdtp-stream.c Takashi Sakamoto 2016-05-09  1370  					u32 tstamp, size_t header_length,
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1371  					void *header, void *private_data)
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1372  {
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1373  	struct amdtp_stream *s = private_data;
da3623abfbef44 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1374  	struct amdtp_domain *d = s->domain;
26cd1e5850b70b sound/firewire/amdtp-stream.c Takashi Sakamoto 2019-05-21  1375  	const __be32 *ctx_header = header;
a04513f8b1980e sound/firewire/amdtp-stream.c Takashi Sakamoto 2017-03-22 @1376  	u32 cycle;
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1377  
bdaedca74d6293 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1378  	// For in-stream, first packet has come.
bdaedca74d6293 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1379  	// For out-stream, prepared to transmit first packet
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1380  	s->callbacked = true;
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1381  
cc4f8e91c4ed04 sound/firewire/amdtp-stream.c Takashi Sakamoto 2019-03-17  1382  	if (s->direction == AMDTP_IN_STREAM) {
3e106f4f690ef0 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-18  1383  		cycle = compute_ohci_cycle_count(ctx_header[1]);
a04513f8b1980e sound/firewire/amdtp-stream.c Takashi Sakamoto 2017-03-22  1384  
a1c11b8ba891b0 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-23  1385  		context->callback.sc = drop_tx_packets_initially;
a04513f8b1980e sound/firewire/amdtp-stream.c Takashi Sakamoto 2017-03-22  1386  	} else {
3e106f4f690ef0 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-18  1387  		cycle = compute_ohci_it_cycle(*ctx_header, s->queue_size);
26cd1e5850b70b sound/firewire/amdtp-stream.c Takashi Sakamoto 2019-05-21  1388  
da3623abfbef44 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1389  		if (s == d->irq_target)
9b1fcd9bf80206 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1390  			context->callback.sc = irq_target_callback_skip;
2472cfb3232caf sound/firewire/amdtp-stream.c Takashi Sakamoto 2020-05-08  1391  		else
9b1fcd9bf80206 sound/firewire/amdtp-stream.c Takashi Sakamoto 2021-05-20  1392  			context->callback.sc = skip_rx_packets;
a04513f8b1980e sound/firewire/amdtp-stream.c Takashi Sakamoto 2017-03-22  1393  	}
a04513f8b1980e sound/firewire/amdtp-stream.c Takashi Sakamoto 2017-03-22  1394  
73fc7f080105b1 sound/firewire/amdtp-stream.c Takashi Sakamoto 2016-05-09  1395  	context->callback.sc(context, tstamp, header_length, header, s);
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1396  }
7b3b0d8583c926 sound/firewire/amdtp.c        Takashi Sakamoto 2014-04-25  1397  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 6dceb8cd6e0c..3576cda3f000 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -49,8 +49,10 @@ 
 #define CIP_FMT_MASK		0x3f000000
 #define CIP_FDF_MASK		0x00ff0000
 #define CIP_FDF_SHIFT		16
+#define CIP_FDF_NO_DATA		0xff
 #define CIP_SYT_MASK		0x0000ffff
 #define CIP_SYT_NO_INFO		0xffff
+#define CIP_NO_DATA		((CIP_FDF_NO_DATA << CIP_FDF_SHIFT) | CIP_SYT_NO_INFO)
 
 #define CIP_HEADER_SIZE		(sizeof(__be32) * CIP_HEADER_QUADLETS)
 
@@ -1198,6 +1200,99 @@  static void process_tx_packets_intermediately(struct fw_iso_context *context, u3
 	}
 }
 
+static void drop_tx_packets_initially(struct fw_iso_context *context, u32 tstamp,
+				      size_t header_length, void *header, void *private_data)
+{
+	struct amdtp_stream *s = private_data;
+	struct amdtp_domain *d = s->domain;
+	__be32 *ctx_header;
+	unsigned int count;
+	unsigned int events;
+	int i;
+
+	if (s->packet_index < 0)
+		return;
+
+	count = header_length / s->ctx_data.tx.ctx_header_size;
+
+	// Attempt to detect any event in the batch of packets.
+	events = 0;
+	ctx_header = header;
+	for (i = 0; i < count; ++i) {
+		unsigned int payload_quads =
+			(be32_to_cpu(*ctx_header) >> ISO_DATA_LENGTH_SHIFT) / sizeof(__be32);
+		unsigned int data_blocks;
+
+		if (s->flags & CIP_NO_HEADER) {
+			data_blocks = payload_quads / s->data_block_quadlets;
+		} else {
+			__be32 *cip_headers = ctx_header + IR_CTX_HEADER_DEFAULT_QUADLETS;
+
+			if (payload_quads < CIP_HEADER_QUADLETS) {
+				data_blocks = 0;
+			} else {
+				payload_quads -= CIP_HEADER_QUADLETS;
+
+				if (s->flags & CIP_UNAWARE_SYT) {
+					data_blocks = payload_quads / s->data_block_quadlets;
+				} else {
+					u32 cip1 = be32_to_cpu(cip_headers[1]);
+
+					// NODATA packet can includes any data blocks but they are
+					// not available as event.
+					if ((cip1 & CIP_NO_DATA) == CIP_NO_DATA)
+						data_blocks = 0;
+					else
+						data_blocks = payload_quads / s->data_block_quadlets;
+				}
+			}
+		}
+
+		events += data_blocks;
+
+		ctx_header += s->ctx_data.tx.ctx_header_size / sizeof(__be32);
+	}
+
+	drop_tx_packets(context, tstamp, header_length, header, s);
+
+	if (events > 0)
+		s->ctx_data.tx.event_starts = true;
+
+	// Decide the cycle count to begin processing content of packet in IR contexts.
+	{
+		unsigned int stream_count = 0;
+		unsigned int event_starts_count = 0;
+		unsigned int cycle = UINT_MAX;
+
+		list_for_each_entry(s, &d->streams, list) {
+			if (s->direction == AMDTP_IN_STREAM) {
+				++stream_count;
+				if (s->ctx_data.tx.event_starts)
+					++event_starts_count;
+			}
+		}
+
+		if (stream_count == event_starts_count) {
+			unsigned int next_cycle;
+
+			list_for_each_entry(s, &d->streams, list) {
+				if (s->direction != AMDTP_IN_STREAM)
+					continue;
+
+				next_cycle = increment_ohci_cycle_count(s->next_cycle,
+								d->processing_cycle.tx_init_skip);
+				if (cycle == UINT_MAX ||
+				    compare_ohci_cycle_count(next_cycle, cycle) > 0)
+					cycle = next_cycle;
+
+				s->context->callback.sc = process_tx_packets_intermediately;
+			}
+
+			d->processing_cycle.tx_start = cycle;
+		}
+	}
+}
+
 static void process_ctxs_in_domain(struct amdtp_domain *d)
 {
 	struct amdtp_stream *s;
@@ -1287,7 +1382,7 @@  static void amdtp_stream_first_callback(struct fw_iso_context *context,
 	if (s->direction == AMDTP_IN_STREAM) {
 		cycle = compute_ohci_cycle_count(ctx_header[1]);
 
-		context->callback.sc = drop_tx_packets;
+		context->callback.sc = drop_tx_packets_initially;
 	} else {
 		cycle = compute_ohci_it_cycle(*ctx_header, s->queue_size);
 
@@ -1298,38 +1393,6 @@  static void amdtp_stream_first_callback(struct fw_iso_context *context,
 	}
 
 	context->callback.sc(context, tstamp, header_length, header, s);
-
-	// Decide the cycle count to begin processing content of packet in IR contexts.
-	if (s->direction == AMDTP_IN_STREAM) {
-		unsigned int stream_count = 0;
-		unsigned int callbacked_count = 0;
-
-		list_for_each_entry(s, &d->streams, list) {
-			if (s->direction == AMDTP_IN_STREAM) {
-				++stream_count;
-				if (s->callbacked)
-					++callbacked_count;
-			}
-		}
-
-		if (stream_count == callbacked_count) {
-			unsigned int next_cycle;
-
-			list_for_each_entry(s, &d->streams, list) {
-				if (s->direction != AMDTP_IN_STREAM)
-					continue;
-
-				next_cycle = increment_ohci_cycle_count(s->next_cycle,
-								d->processing_cycle.tx_init_skip);
-				if (compare_ohci_cycle_count(next_cycle, cycle) > 0)
-					cycle = next_cycle;
-
-				s->context->callback.sc = process_tx_packets_intermediately;
-			}
-
-			d->processing_cycle.tx_start = cycle;
-		}
-	}
 }
 
 /**
@@ -1409,6 +1472,7 @@  static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
 	if (s->direction == AMDTP_IN_STREAM) {
 		s->ctx_data.tx.max_ctx_payload_length = max_ctx_payload_size;
 		s->ctx_data.tx.ctx_header_size = ctx_header_size;
+		s->ctx_data.tx.event_starts = false;
 	} else {
 		static const struct {
 			unsigned int data_block;
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 467d5021624b..d3ba2e1c1522 100644
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -138,6 +138,9 @@  struct amdtp_stream {
 			// Fixed interval of dbc between previos/current
 			// packets.
 			unsigned int dbc_interval;
+
+			// The device starts multiplexing events to the packet.
+			bool event_starts;
 		} tx;
 		struct {
 			// To generate CIP header.