path: root/Documentation
diff options
Diffstat (limited to 'Documentation')
2 files changed, 3 insertions, 16 deletions
diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index 8b4ad809df27..897f942b976b 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -88,15 +88,8 @@ 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. This
-field is DEPRECATED. Only one driver computes this value. New device
-drivers must leave this zero. Instead, they can expose the hardware
+hwtimetrans is always zero. This field is deprecated. It used to hold
+hw timestamps converted to system time. Instead, expose the hardware
clock device on the NIC directly as a HW PTP clock source, to allow
time conversion in userspace and optionally synchronize system time
with a userspace PTP stack such as linuxptp. For the PTP clock API,
@@ -191,7 +184,6 @@ struct skb_shared_hwtstamps {
* since arbitrary point in time
ktime_t hwtstamp;
- ktime_t syststamp; /* hwtstamp transformed to system time base */
Time stamps for outgoing packets are to be generated as follows:
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
index 8ba82bfe6a33..5cdfd743447b 100644
--- a/Documentation/networking/timestamping/timestamping.c
+++ b/Documentation/networking/timestamping/timestamping.c
@@ -76,7 +76,6 @@ static void usage(const char *error)
" 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");
@@ -202,9 +201,7 @@ static void printpacket(struct msghdr *msg, int res,
- printf("HW transformed %ld.%09ld ",
- (long)stamp->tv_sec,
- (long)stamp->tv_nsec);
+ /* skip deprecated HW transformed */
printf("HW raw %ld.%09ld",
@@ -361,8 +358,6 @@ int main(int argc, char **argv)
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;

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