Add basic IEEE-1588 PTP server/client

What works:
- Basic server & client operation
- Transmission and reception of announce, sync and follow-up

Still missing:
- SO_TIMINGS for getting more precise packet timestamps
- Implementation of delay_req and delay_resp packets
- Status and stop interfaces for the daemon

include/netutils/ptpd.h

@@ -0,0 +1,71 @@
+/****************************************************************************
+ * apps/include/netutils/ptpd.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __APPS_INCLUDE_NETUTILS_PTPD_H
+#define __APPS_INCLUDE_NETUTILS_PTPD_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: ptpd_start
+ *
+ * Description:
+ *   Start the PTP daemon and bind it to specified interface.
+ *
+ * Returned Value:
+ *   On success, the non-negative task ID of the PTP daemon is returned;
+ *   On failure, a negated errno value is returned.
+ *
+ ****************************************************************************/
+
+int ptpd_start(const char *interface);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __APPS_INCLUDE_NETUTILS_PTPD_H */

netutils/ptpd/Kconfig

@@ -0,0 +1,167 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config NETUTILS_PTPD
+	bool "PTPD client/server"
+	default n
+	select NET_IPv4
+	select NET_IGMP
+	select NET_UDP
+	---help---
+		Build a minimal implementation of IEEE-1588 precision time protocol.
+		Uses system gettimeofday() and adjtime() calls to synchronize clock
+		with a master clock through network, or to provide a master clock to
+		other systems.
+
+if NETUTILS_PTPD
+
+config NETUTILS_PTPD_DEBUG
+	bool "Enable PTP debug messages"
+	default n
+	depends on DEBUG_INFO
+	---help---
+		Enable PTP debug messages even if CONFIG_DEBUG_NET_INFO is not enabled.
+
+config NETUTILS_PTPD_CLIENT
+	bool "Enable client support"
+	default y
+	---help---
+		Act as a PTP client, synchronizing the NuttX clock to a remote master
+		clock.
+
+config NETUTILS_PTPD_SERVER
+	bool "Enable server support"
+	default n
+	---help---
+		Act as a PTP server, providing NuttX clock time to other systems.
+
+		Both server and client can be simultaneously enabled. NuttX will then
+		synchronize to a higher priority master clock, or act as a master
+		clock itself if it has the highest priority.
+		Refer to Best Master Clock algorithm in IEEE-1588 for details.
+
+config NETUTILS_PTPD_STACKSIZE
+	int "PTP daemon stack stack size"
+	default DEFAULT_TASK_STACKSIZE
+
+config NETUTILS_PTPD_SERVERPRIO
+	int "PTP daemon priority"
+	default 100
+
+config NETUTILS_PTPD_DOMAIN
+	int	"PTP domain selection"
+	default 0
+	range 0 127
+	---help---
+		Set PTP domain to participate in. Default domain is 0, other domains
+		can be used to isolate reference clocks from each other.
+
+if NETUTILS_PTPD_SERVER
+
+config NETUTILS_PTPD_PRIORITY1
+	int "PTP server priority1"
+	default 128
+	range 0 255
+	---help---
+		Set clock priority to announce when acting as a PTP server.
+		Lower value is higher priority.
+
+		A higher priority1 clock will be selected without regard to announced
+		clock quality fields.
+		Refer to Best Master Clock algorithm in IEEE-1588 for details.
+
+config NETUTILS_PTPD_PRIORITY2
+	int "PTP server priority2"
+	default 128
+	range 0 255
+	---help---
+		Set clock subpriority to announce when acting as a PTP server.
+		This will distinguish between two clocks that are equivalent in
+		priority1, class and accuracy values.
+		Lower value is higher priority.
+
+config NETUTILS_PTPD_CLASS
+	int "PTP server class"
+	default 248
+	range 0 255
+	---help---
+		Set master clock class to announce when acting as a PTP server.
+		Lower value means higher quality clock source.
+		248 is the default for unknown class.
+
+config NETUTILS_PTPD_ACCURACY
+	int "PTP server accuracy"
+	default 254
+	range 0 255
+	---help---
+		Set master clock accuracy to announce when acting as a PTP server.
+		Logarithmic scale is defined in IEEE-1588:
+		32: +-  25 ns
+		33: +- 100 ns
+		34: +- 250 ns
+		35: +-   1 us
+		36: +-   2.5 us
+		37: +-  10 us
+		38: +-  25 us
+		39: +- 100 us
+		40: +- 250 us
+		41: +-   1 ms
+		42: +-   2.5 ms
+		43: +-  10 ms
+		44: +-  25 ms
+		45: +- 100 ms
+		46: +- 250 ms
+		47: +-   1 s
+		48: +-  10 s
+		49: +-  more than 10 s
+		254: Unknown
+
+config NETUTILS_PTPD_CLOCKSOURCE
+	int "PTP server clock source type"
+	default 160
+	range 0 255
+	---help---
+		Set clock source type to announce when acting as a PTP server.
+		Common values:
+		 32: GPS
+		 64: PTP
+		 80: NTP
+		144: Other
+		160: Internal oscillator
+
+config NETUTILS_PTPD_SYNC_INTERVAL_MSEC
+	int "PTP server sync transmit interval (ms)"
+	default 1000
+	---help---
+		How often to transmit sync packets in server mode.
+
+config NETUTILS_PTPD_ANNOUNCE_INTERVAL_MSEC
+	int "PTP server announce transmit interval (ms)"
+	default 10000
+	---help---
+		How often to transmit announce packets in server mode.
+
+endif # NETUTILS_PTPD_SERVER
+
+if NETUTILS_PTPD_CLIENT
+
+config NETUTILS_PTPD_TIMEOUT_MS
+	int "PTP client timeout for changing clock source (ms)"
+	default 60000
+	---help---
+		If no packets are being received from currently chosen clock source,
+		fall back to next best clock source after this many seconds.
+
+config NETUTILS_PTPD_SETTIME_THRESHOLD_MS
+	int "PTP client threshold for changing system time (ms)"
+	default 1000
+	---help---
+		If difference between local and remote clock exceeds this threshold,
+		time is reset with settimeofday() instead of changing the rate with
+		adjtime().
+
+endif # NETUTILS_PTPD_CLIENT
+
+endif # NETUTILS_PTPD

netutils/ptpd/Make.defs

@@ -0,0 +1,23 @@
+############################################################################
+# apps/netutils/ptpd/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+ifneq ($(CONFIG_NETUTILS_PTPD),)
+CONFIGURED_APPS += $(APPDIR)/netutils/ptpd
+endif

netutils/ptpd/Makefile

@@ -0,0 +1,29 @@
+############################################################################
+# apps/netutils/ptpd/Makefile
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(APPDIR)/Make.defs
+
+# PTP server/client implementation
+
+ifeq ($(CONFIG_NET_UDP),y)
+CSRCS = ptpd.c
+endif
+
+include $(APPDIR)/Application.mk