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-rw-r--r--Documentation/networking/timestamping.txt178
-rw-r--r--Documentation/networking/timestamping/.gitignore1
-rw-r--r--Documentation/networking/timestamping/Makefile6
-rw-r--r--Documentation/networking/timestamping/timestamping.c533
4 files changed, 718 insertions, 0 deletions
diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
new file mode 100644
index 00000000000..a681a65b5bc
--- /dev/null
+++ b/Documentation/networking/timestamping.txt
@@ -0,0 +1,178 @@
+The existing interfaces for getting network packages time stamped are:
+
+* SO_TIMESTAMP
+ Generate time stamp for each incoming packet using the (not necessarily
+ monotonous!) system time. Result is returned via recv_msg() in a
+ control message as timeval (usec resolution).
+
+* SO_TIMESTAMPNS
+ Same time stamping mechanism as SO_TIMESTAMP, but returns result as
+ timespec (nsec resolution).
+
+* IP_MULTICAST_LOOP + SO_TIMESTAMP[NS]
+ Only for multicasts: approximate send time stamp by receiving the looped
+ packet and using its receive time stamp.
+
+The following interface complements the existing ones: receive time
+stamps can be generated and returned for arbitrary packets and much
+closer to the point where the packet is really sent. Time stamps can
+be generated in software (as before) or in hardware (if the hardware
+has such a feature).
+
+SO_TIMESTAMPING:
+
+Instructs the socket layer which kind of information is wanted. The
+parameter is an integer with some of the following bits set. Setting
+other bits is an error and doesn't change the current state.
+
+SOF_TIMESTAMPING_TX_HARDWARE: try to obtain send time stamp in hardware
+SOF_TIMESTAMPING_TX_SOFTWARE: if SOF_TIMESTAMPING_TX_HARDWARE is off or
+ fails, then do it in software
+SOF_TIMESTAMPING_RX_HARDWARE: return the original, unmodified time stamp
+ as generated by the hardware
+SOF_TIMESTAMPING_RX_SOFTWARE: if SOF_TIMESTAMPING_RX_HARDWARE is off or
+ fails, then do it in software
+SOF_TIMESTAMPING_RAW_HARDWARE: return original raw hardware time stamp
+SOF_TIMESTAMPING_SYS_HARDWARE: return hardware time stamp transformed to
+ the system time base
+SOF_TIMESTAMPING_SOFTWARE: return system time stamp generated in
+ software
+
+SOF_TIMESTAMPING_TX/RX determine how time stamps are generated.
+SOF_TIMESTAMPING_RAW/SYS determine how they are reported in the
+following control message:
+ struct scm_timestamping {
+ struct timespec systime;
+ struct timespec hwtimetrans;
+ struct timespec hwtimeraw;
+ };
+
+recvmsg() can be used to get this control message for regular incoming
+packets. For send time stamps the outgoing packet is looped back to
+the socket's error queue with the send time stamp(s) attached. It can
+be received with recvmsg(flags=MSG_ERRQUEUE). The call returns the
+original outgoing packet data including all headers preprended down to
+and including the link layer, the scm_timestamping control message and
+a sock_extended_err control message with ee_errno==ENOMSG and
+ee_origin==SO_EE_ORIGIN_TIMESTAMPING. A socket with such a pending
+bounced packet is ready for reading as far as select() is concerned.
+
+All three values correspond to the same event in time, but were
+generated in different ways. Each of these values may be empty (= all
+zero), in which case no such value was available. If the application
+is not interested in some of these values, they can be left blank to
+avoid the potential overhead of calculating them.
+
+systime is the value of the system time at that moment. This
+corresponds to the value also returned via SO_TIMESTAMP[NS]. If the
+time stamp was generated by hardware, then this field is
+empty. Otherwise it is filled in if SOF_TIMESTAMPING_SOFTWARE is
+set.
+
+hwtimeraw is the original hardware time stamp. Filled in if
+SOF_TIMESTAMPING_RAW_HARDWARE is set. No assumptions about its
+relation to system time should be made.
+
+hwtimetrans is the hardware time stamp transformed so that it
+corresponds as good as possible to system time. This correlation is
+not perfect; as a consequence, sorting packets received via different
+NICs by their hwtimetrans may differ from the order in which they were
+received. hwtimetrans may be non-monotonic even for the same NIC.
+Filled in if SOF_TIMESTAMPING_SYS_HARDWARE is set. Requires support
+by the network device and will be empty without that support.
+
+
+SIOCSHWTSTAMP:
+
+Hardware time stamping must also be initialized for each device driver
+that is expected to do hardware time stamping. The parameter is:
+
+struct hwtstamp_config {
+ int flags; /* no flags defined right now, must be zero */
+ int tx_type; /* HWTSTAMP_TX_* */
+ int rx_filter; /* HWTSTAMP_FILTER_* */
+};
+
+Desired behavior is passed into the kernel and to a specific device by
+calling ioctl(SIOCSHWTSTAMP) with a pointer to a struct ifreq whose
+ifr_data points to a struct hwtstamp_config. The tx_type and
+rx_filter are hints to the driver what it is expected to do. If
+the requested fine-grained filtering for incoming packets is not
+supported, the driver may time stamp more than just the requested types
+of packets.
+
+A driver which supports hardware time stamping shall update the struct
+with the actual, possibly more permissive configuration. If the
+requested packets cannot be time stamped, then nothing should be
+changed and ERANGE shall be returned (in contrast to EINVAL, which
+indicates that SIOCSHWTSTAMP is not supported at all).
+
+Only a processes with admin rights may change the configuration. User
+space is responsible to ensure that multiple processes don't interfere
+with each other and that the settings are reset.
+
+/* possible values for hwtstamp_config->tx_type */
+enum {
+ /*
+ * no outgoing packet will need hardware time stamping;
+ * should a packet arrive which asks for it, no hardware
+ * time stamping will be done
+ */
+ HWTSTAMP_TX_OFF,
+
+ /*
+ * enables hardware time stamping for outgoing packets;
+ * the sender of the packet decides which are to be
+ * time stamped by setting SOF_TIMESTAMPING_TX_SOFTWARE
+ * before sending the packet
+ */
+ HWTSTAMP_TX_ON,
+};
+
+/* possible values for hwtstamp_config->rx_filter */
+enum {
+ /* time stamp no incoming packet at all */
+ HWTSTAMP_FILTER_NONE,
+
+ /* time stamp any incoming packet */
+ HWTSTAMP_FILTER_ALL,
+
+ /* return value: time stamp all packets requested plus some others */
+ HWTSTAMP_FILTER_SOME,
+
+ /* PTP v1, UDP, any kind of event packet */
+ HWTSTAMP_FILTER_PTP_V1_L4_EVENT,
+
+ ...
+};
+
+
+DEVICE IMPLEMENTATION
+
+A driver which supports hardware time stamping must support the
+SIOCSHWTSTAMP ioctl. Time stamps for received packets must be stored
+in the skb with skb_hwtstamp_set().
+
+Time stamps for outgoing packets are to be generated as follows:
+- In hard_start_xmit(), check if skb_hwtstamp_check_tx_hardware()
+ returns non-zero. If yes, then the driver is expected
+ to do hardware time stamping.
+- If this is possible for the skb and requested, then declare
+ that the driver is doing the time stamping by calling
+ skb_hwtstamp_tx_in_progress(). A driver not supporting
+ hardware time stamping doesn't do that. A driver must never
+ touch sk_buff::tstamp! It is used to store how time stamping
+ for an outgoing packets is to be done.
+- As soon as the driver has sent the packet and/or obtained a
+ hardware time stamp for it, it passes the time stamp back by
+ calling skb_hwtstamp_tx() with the original skb, the raw
+ hardware time stamp and a handle to the device (necessary
+ to convert the hardware time stamp to system time). If obtaining
+ the hardware time stamp somehow fails, then the driver should
+ not fall back to software time stamping. The rationale is that
+ this would occur at a later time in the processing pipeline
+ than other software time stamping and therefore could lead
+ to unexpected deltas between time stamps.
+- If the driver did not call skb_hwtstamp_tx_in_progress(), then
+ dev_hard_start_xmit() checks whether software time stamping
+ is wanted as fallback and potentially generates the time stamp.
diff --git a/Documentation/networking/timestamping/.gitignore b/Documentation/networking/timestamping/.gitignore
new file mode 100644
index 00000000000..71e81eb2e22
--- /dev/null
+++ b/Documentation/networking/timestamping/.gitignore
@@ -0,0 +1 @@
+timestamping
diff --git a/Documentation/networking/timestamping/Makefile b/Documentation/networking/timestamping/Makefile
new file mode 100644
index 00000000000..2a1489fdc03
--- /dev/null
+++ b/Documentation/networking/timestamping/Makefile
@@ -0,0 +1,6 @@
+CPPFLAGS = -I../../../include
+
+timestamping: timestamping.c
+
+clean:
+ rm -f timestamping
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
new file mode 100644
index 00000000000..43d14310421
--- /dev/null
+++ b/Documentation/networking/timestamping/timestamping.c
@@ -0,0 +1,533 @@
+/*
+ * This program demonstrates how the various time stamping features in
+ * the Linux kernel work. It emulates the behavior of a PTP
+ * implementation in stand-alone master mode by sending PTPv1 Sync
+ * multicasts once every second. It looks for similar packets, but
+ * beyond that doesn't actually implement PTP.
+ *
+ * Outgoing packets are time stamped with SO_TIMESTAMPING with or
+ * without hardware support.
+ *
+ * Incoming packets are time stamped with SO_TIMESTAMPING with or
+ * without hardware support, SIOCGSTAMP[NS] (per-socket time stamp) and
+ * SO_TIMESTAMP[NS].
+ *
+ * Copyright (C) 2009 Intel Corporation.
+ * Author: Patrick Ohly <patrick.ohly@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <sys/select.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+
+#include "asm/types.h"
+#include "linux/net_tstamp.h"
+#include "linux/errqueue.h"
+
+#ifndef SO_TIMESTAMPING
+# define SO_TIMESTAMPING 37
+# define SCM_TIMESTAMPING SO_TIMESTAMPING
+#endif
+
+#ifndef SO_TIMESTAMPNS
+# define SO_TIMESTAMPNS 35
+#endif
+
+#ifndef SIOCGSTAMPNS
+# define SIOCGSTAMPNS 0x8907
+#endif
+
+#ifndef SIOCSHWTSTAMP
+# define SIOCSHWTSTAMP 0x89b0
+#endif
+
+static void usage(const char *error)
+{
+ if (error)
+ printf("invalid option: %s\n", error);
+ printf("timestamping interface option*\n\n"
+ "Options:\n"
+ " IP_MULTICAST_LOOP - looping outgoing multicasts\n"
+ " SO_TIMESTAMP - normal software time stamping, ms resolution\n"
+ " SO_TIMESTAMPNS - more accurate software time stamping\n"
+ " SOF_TIMESTAMPING_TX_HARDWARE - hardware time stamping of outgoing packets\n"
+ " SOF_TIMESTAMPING_TX_SOFTWARE - software fallback for outgoing packets\n"
+ " SOF_TIMESTAMPING_RX_HARDWARE - hardware time stamping of incoming packets\n"
+ " SOF_TIMESTAMPING_RX_SOFTWARE - software fallback for incoming packets\n"
+ " SOF_TIMESTAMPING_SOFTWARE - request reporting of software time stamps\n"
+ " SOF_TIMESTAMPING_SYS_HARDWARE - request reporting of transformed HW time stamps\n"
+ " SOF_TIMESTAMPING_RAW_HARDWARE - request reporting of raw HW time stamps\n"
+ " SIOCGSTAMP - check last socket time stamp\n"
+ " SIOCGSTAMPNS - more accurate socket time stamp\n");
+ exit(1);
+}
+
+static void bail(const char *error)
+{
+ printf("%s: %s\n", error, strerror(errno));
+ exit(1);
+}
+
+static const unsigned char sync[] = {
+ 0x00, 0x01, 0x00, 0x01,
+ 0x5f, 0x44, 0x46, 0x4c,
+ 0x54, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x01, 0x01,
+
+ /* fake uuid */
+ 0x00, 0x01,
+ 0x02, 0x03, 0x04, 0x05,
+
+ 0x00, 0x01, 0x00, 0x37,
+ 0x00, 0x00, 0x00, 0x08,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x49, 0x05, 0xcd, 0x01,
+ 0x29, 0xb1, 0x8d, 0xb0,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x01,
+
+ /* fake uuid */
+ 0x00, 0x01,
+ 0x02, 0x03, 0x04, 0x05,
+
+ 0x00, 0x00, 0x00, 0x37,
+ 0x00, 0x00, 0x00, 0x04,
+ 0x44, 0x46, 0x4c, 0x54,
+ 0x00, 0x00, 0xf0, 0x60,
+ 0x00, 0x01, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x01,
+ 0x00, 0x00, 0xf0, 0x60,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x04,
+ 0x44, 0x46, 0x4c, 0x54,
+ 0x00, 0x01,
+
+ /* fake uuid */
+ 0x00, 0x01,
+ 0x02, 0x03, 0x04, 0x05,
+
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00
+};
+
+static void sendpacket(int sock, struct sockaddr *addr, socklen_t addr_len)
+{
+ struct timeval now;
+ int res;
+
+ res = sendto(sock, sync, sizeof(sync), 0,
+ addr, addr_len);
+ gettimeofday(&now, 0);
+ if (res < 0)
+ printf("%s: %s\n", "send", strerror(errno));
+ else
+ printf("%ld.%06ld: sent %d bytes\n",
+ (long)now.tv_sec, (long)now.tv_usec,
+ res);
+}
+
+static void printpacket(struct msghdr *msg, int res,
+ char *data,
+ int sock, int recvmsg_flags,
+ int siocgstamp, int siocgstampns)
+{
+ struct sockaddr_in *from_addr = (struct sockaddr_in *)msg->msg_name;
+ struct cmsghdr *cmsg;
+ struct timeval tv;
+ struct timespec ts;
+ struct timeval now;
+
+ gettimeofday(&now, 0);
+
+ printf("%ld.%06ld: received %s data, %d bytes from %s, %d bytes control messages\n",
+ (long)now.tv_sec, (long)now.tv_usec,
+ (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
+ res,
+ inet_ntoa(from_addr->sin_addr),
+ msg->msg_controllen);
+ for (cmsg = CMSG_FIRSTHDR(msg);
+ cmsg;
+ cmsg = CMSG_NXTHDR(msg, cmsg)) {
+ printf(" cmsg len %d: ", cmsg->cmsg_len);
+ switch (cmsg->cmsg_level) {
+ case SOL_SOCKET:
+ printf("SOL_SOCKET ");
+ switch (cmsg->cmsg_type) {
+ case SO_TIMESTAMP: {
+ struct timeval *stamp =
+ (struct timeval *)CMSG_DATA(cmsg);
+ printf("SO_TIMESTAMP %ld.%06ld",
+ (long)stamp->tv_sec,
+ (long)stamp->tv_usec);
+ break;
+ }
+ case SO_TIMESTAMPNS: {
+ struct timespec *stamp =
+ (struct timespec *)CMSG_DATA(cmsg);
+ printf("SO_TIMESTAMPNS %ld.%09ld",
+ (long)stamp->tv_sec,
+ (long)stamp->tv_nsec);
+ break;
+ }
+ case SO_TIMESTAMPING: {
+ struct timespec *stamp =
+ (struct timespec *)CMSG_DATA(cmsg);
+ printf("SO_TIMESTAMPING ");
+ printf("SW %ld.%09ld ",
+ (long)stamp->tv_sec,
+ (long)stamp->tv_nsec);
+ stamp++;
+ printf("HW transformed %ld.%09ld ",
+ (long)stamp->tv_sec,
+ (long)stamp->tv_nsec);
+ stamp++;
+ printf("HW raw %ld.%09ld",
+ (long)stamp->tv_sec,
+ (long)stamp->tv_nsec);
+ break;
+ }
+ default:
+ printf("type %d", cmsg->cmsg_type);
+ break;
+ }
+ break;
+ case IPPROTO_IP:
+ printf("IPPROTO_IP ");
+ switch (cmsg->cmsg_type) {
+ case IP_RECVERR: {
+ struct sock_extended_err *err =
+ (struct sock_extended_err *)CMSG_DATA(cmsg);
+ printf("IP_RECVERR ee_errno '%s' ee_origin %d => %s",
+ strerror(err->ee_errno),
+ err->ee_origin,
+#ifdef SO_EE_ORIGIN_TIMESTAMPING
+ err->ee_origin == SO_EE_ORIGIN_TIMESTAMPING ?
+ "bounced packet" : "unexpected origin"
+#else
+ "probably SO_EE_ORIGIN_TIMESTAMPING"
+#endif
+ );
+ if (res < sizeof(sync))
+ printf(" => truncated data?!");
+ else if (!memcmp(sync, data + res - sizeof(sync),
+ sizeof(sync)))
+ printf(" => GOT OUR DATA BACK (HURRAY!)");
+ break;
+ }
+ case IP_PKTINFO: {
+ struct in_pktinfo *pktinfo =
+ (struct in_pktinfo *)CMSG_DATA(cmsg);
+ printf("IP_PKTINFO interface index %u",
+ pktinfo->ipi_ifindex);
+ break;
+ }
+ default:
+ printf("type %d", cmsg->cmsg_type);
+ break;
+ }
+ break;
+ default:
+ printf("level %d type %d",
+ cmsg->cmsg_level,
+ cmsg->cmsg_type);
+ break;
+ }
+ printf("\n");
+ }
+
+ if (siocgstamp) {
+ if (ioctl(sock, SIOCGSTAMP, &tv))
+ printf(" %s: %s\n", "SIOCGSTAMP", strerror(errno));
+ else
+ printf("SIOCGSTAMP %ld.%06ld\n",
+ (long)tv.tv_sec,
+ (long)tv.tv_usec);
+ }
+ if (siocgstampns) {
+ if (ioctl(sock, SIOCGSTAMPNS, &ts))
+ printf(" %s: %s\n", "SIOCGSTAMPNS", strerror(errno));
+ else
+ printf("SIOCGSTAMPNS %ld.%09ld\n",
+ (long)ts.tv_sec,
+ (long)ts.tv_nsec);
+ }
+}
+
+static void recvpacket(int sock, int recvmsg_flags,
+ int siocgstamp, int siocgstampns)
+{
+ char data[256];
+ struct msghdr msg;
+ struct iovec entry;
+ struct sockaddr_in from_addr;
+ struct {
+ struct cmsghdr cm;
+ char control[512];
+ } control;
+ int res;
+
+ memset(&msg, 0, sizeof(msg));
+ msg.msg_iov = &entry;
+ msg.msg_iovlen = 1;
+ entry.iov_base = data;
+ entry.iov_len = sizeof(data);
+ msg.msg_name = (caddr_t)&from_addr;
+ msg.msg_namelen = sizeof(from_addr);
+ msg.msg_control = &control;
+ msg.msg_controllen = sizeof(control);
+
+ res = recvmsg(sock, &msg, recvmsg_flags|MSG_DONTWAIT);
+ if (res < 0) {
+ printf("%s %s: %s\n",
+ "recvmsg",
+ (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
+ strerror(errno));
+ } else {
+ printpacket(&msg, res, data,
+ sock, recvmsg_flags,
+ siocgstamp, siocgstampns);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int so_timestamping_flags = 0;
+ int so_timestamp = 0;
+ int so_timestampns = 0;
+ int siocgstamp = 0;
+ int siocgstampns = 0;
+ int ip_multicast_loop = 0;
+ char *interface;
+ int i;
+ int enabled = 1;
+ int sock;
+ struct ifreq device;
+ struct ifreq hwtstamp;
+ struct hwtstamp_config hwconfig, hwconfig_requested;
+ struct sockaddr_in addr;
+ struct ip_mreq imr;
+ struct in_addr iaddr;
+ int val;
+ socklen_t len;
+ struct timeval next;
+
+ if (argc < 2)
+ usage(0);
+ interface = argv[1];
+
+ for (i = 2; i < argc; i++) {
+ if (!strcasecmp(argv[i], "SO_TIMESTAMP"))
+ so_timestamp = 1;
+ else if (!strcasecmp(argv[i], "SO_TIMESTAMPNS"))
+ so_timestampns = 1;
+ else if (!strcasecmp(argv[i], "SIOCGSTAMP"))
+ siocgstamp = 1;
+ else if (!strcasecmp(argv[i], "SIOCGSTAMPNS"))
+ siocgstampns = 1;
+ else if (!strcasecmp(argv[i], "IP_MULTICAST_LOOP"))
+ ip_multicast_loop = 1;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_HARDWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_TX_HARDWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_SOFTWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_TX_SOFTWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_HARDWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_RX_HARDWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_SOFTWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_RX_SOFTWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SOFTWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_SOFTWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SYS_HARDWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_SYS_HARDWARE;
+ else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RAW_HARDWARE"))
+ so_timestamping_flags |= SOF_TIMESTAMPING_RAW_HARDWARE;
+ else
+ usage(argv[i]);
+ }
+
+ sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ if (socket < 0)
+ bail("socket");
+
+ memset(&device, 0, sizeof(device));
+ strncpy(device.ifr_name, interface, sizeof(device.ifr_name));
+ if (ioctl(sock, SIOCGIFADDR, &device) < 0)
+ bail("getting interface IP address");
+
+ memset(&hwtstamp, 0, sizeof(hwtstamp));
+ strncpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name));
+ hwtstamp.ifr_data = (void *)&hwconfig;
+ memset(&hwconfig, 0, sizeof(&hwconfig));
+ hwconfig.tx_type =
+ (so_timestamping_flags & SOF_TIMESTAMPING_TX_HARDWARE) ?
+ HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
+ hwconfig.rx_filter =
+ (so_timestamping_flags & SOF_TIMESTAMPING_RX_HARDWARE) ?
+ HWTSTAMP_FILTER_PTP_V1_L4_SYNC : HWTSTAMP_FILTER_NONE;
+ hwconfig_requested = hwconfig;
+ if (ioctl(sock, SIOCSHWTSTAMP, &hwtstamp) < 0) {
+ if ((errno == EINVAL || errno == ENOTSUP) &&
+ hwconfig_requested.tx_type == HWTSTAMP_TX_OFF &&
+ hwconfig_requested.rx_filter == HWTSTAMP_FILTER_NONE)
+ printf("SIOCSHWTSTAMP: disabling hardware time stamping not possible\n");
+ else
+ bail("SIOCSHWTSTAMP");
+ }
+ printf("SIOCSHWTSTAMP: tx_type %d requested, got %d; rx_filter %d requested, got %d\n",
+ hwconfig_requested.tx_type, hwconfig.tx_type,
+ hwconfig_requested.rx_filter, hwconfig.rx_filter);
+
+ /* bind to PTP port */
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = htonl(INADDR_ANY);
+ addr.sin_port = htons(319 /* PTP event port */);
+ if (bind(sock,
+ (struct sockaddr *)&addr,
+ sizeof(struct sockaddr_in)) < 0)
+ bail("bind");
+
+ /* set multicast group for outgoing packets */
+ inet_aton("224.0.1.130", &iaddr); /* alternate PTP domain 1 */
+ addr.sin_addr = iaddr;
+ imr.imr_multiaddr.s_addr = iaddr.s_addr;
+ imr.imr_interface.s_addr =
+ ((struct sockaddr_in *)&device.ifr_addr)->sin_addr.s_addr;
+ if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF,
+ &imr.imr_interface.s_addr, sizeof(struct in_addr)) < 0)
+ bail("set multicast");
+
+ /* join multicast group, loop our own packet */
+ if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+ &imr, sizeof(struct ip_mreq)) < 0)
+ bail("join multicast group");
+
+ if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_LOOP,
+ &ip_multicast_loop, sizeof(enabled)) < 0) {
+ bail("loop multicast");
+ }
+
+ /* set socket options for time stamping */
+ if (so_timestamp &&
+ setsockopt(sock, SOL_SOCKET, SO_TIMESTAMP,
+ &enabled, sizeof(enabled)) < 0)
+ bail("setsockopt SO_TIMESTAMP");
+
+ if (so_timestampns &&
+ setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS,
+ &enabled, sizeof(enabled)) < 0)
+ bail("setsockopt SO_TIMESTAMPNS");
+
+ if (so_timestamping_flags &&
+ setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING,
+ &so_timestamping_flags,
+ sizeof(so_timestamping_flags)) < 0)
+ bail("setsockopt SO_TIMESTAMPING");
+
+ /* request IP_PKTINFO for debugging purposes */
+ if (setsockopt(sock, SOL_IP, IP_PKTINFO,
+ &enabled, sizeof(enabled)) < 0)
+ printf("%s: %s\n", "setsockopt IP_PKTINFO", strerror(errno));
+
+ /* verify socket options */
+ len = sizeof(val);
+ if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, &val, &len) < 0)
+ printf("%s: %s\n", "getsockopt SO_TIMESTAMP", strerror(errno));
+ else
+ printf("SO_TIMESTAMP %d\n", val);
+
+ if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS, &val, &len) < 0)
+ printf("%s: %s\n", "getsockopt SO_TIMESTAMPNS",
+ strerror(errno));
+ else
+ printf("SO_TIMESTAMPNS %d\n", val);
+
+ if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING, &val, &len) < 0) {
+ printf("%s: %s\n", "getsockopt SO_TIMESTAMPING",
+ strerror(errno));
+ } else {
+ printf("SO_TIMESTAMPING %d\n", val);
+ if (val != so_timestamping_flags)
+ printf(" not the expected value %d\n",
+ so_timestamping_flags);
+ }
+
+ /* send packets forever every five seconds */
+ gettimeofday(&next, 0);
+ next.tv_sec = (next.tv_sec + 1) / 5 * 5;
+ next.tv_usec = 0;
+ while (1) {
+ struct timeval now;
+ struct timeval delta;
+ long delta_us;
+ int res;
+ fd_set readfs, errorfs;
+
+ gettimeofday(&now, 0);
+ delta_us = (long)(next.tv_sec - now.tv_sec) * 1000000 +
+ (long)(next.tv_usec - now.tv_usec);
+ if (delta_us > 0) {
+ /* continue waiting for timeout or data */
+ delta.tv_sec = delta_us / 1000000;
+ delta.tv_usec = delta_us % 1000000;
+
+ FD_ZERO(&readfs);
+ FD_ZERO(&errorfs);
+ FD_SET(sock, &readfs);
+ FD_SET(sock, &errorfs);
+ printf("%ld.%06ld: select %ldus\n",
+ (long)now.tv_sec, (long)now.tv_usec,
+ delta_us);
+ res = select(sock + 1, &readfs, 0, &errorfs, &delta);
+ gettimeofday(&now, 0);
+ printf("%ld.%06ld: select returned: %d, %s\n",
+ (long)now.tv_sec, (long)now.tv_usec,
+ res,
+ res < 0 ? strerror(errno) : "success");
+ if (res > 0) {
+ if (FD_ISSET(sock, &readfs))
+ printf("ready for reading\n");
+ if (FD_ISSET(sock, &errorfs))
+ printf("has error\n");
+ recvpacket(sock, 0,
+ siocgstamp,
+ siocgstampns);
+ recvpacket(sock, MSG_ERRQUEUE,
+ siocgstamp,
+ siocgstampns);
+ }
+ } else {
+ /* write one packet */
+ sendpacket(sock,
+ (struct sockaddr *)&addr,
+ sizeof(addr));
+ next.tv_sec += 5;
+ continue;
+ }
+ }
+
+ return 0;
+}