Commit 51eb7492 authored by Gerhard Engleder's avatar Gerhard Engleder Committed by Paolo Abeni
Browse files

ptp: Request cycles for TX timestamp 



The free running cycle counter of physical clocks called cycles shall be
used for hardware timestamps to enable synchronisation.

Introduce new flag SKBTX_HW_TSTAMP_USE_CYCLES, which signals driver to
provide a TX timestamp based on cycles if cycles are supported.

Signed-off-by: default avatarGerhard Engleder <gerhard@engleder-embedded.com>
Acked-by: default avatarRichard Cochran <richardcochran@gmail.com>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 42704b26

include/linux/skbuff.h

+6 −1
Original line number Diff line number Diff line
@@ -615,6 +615,9 @@ enum { 
	/* device driver is going to provide hardware time stamp */

	SKBTX_IN_PROGRESS = 1 << 2,



	/* generate hardware time stamp based on cycles if supported */

	SKBTX_HW_TSTAMP_USE_CYCLES = 1 << 3,



	/* generate wifi status information (where possible) */

	SKBTX_WIFI_STATUS = 1 << 4,
@@ -624,7 +627,9 @@ enum { 


#define SKBTX_ANY_SW_TSTAMP	(SKBTX_SW_TSTAMP    | \

				 SKBTX_SCHED_TSTAMP)

#define SKBTX_ANY_TSTAMP	(SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)

#define SKBTX_ANY_TSTAMP	(SKBTX_HW_TSTAMP | \

				 SKBTX_HW_TSTAMP_USE_CYCLES | \

				 SKBTX_ANY_SW_TSTAMP)



/* Definitions for flags in struct skb_shared_info */

enum {

net/socket.c

+10 −1
Original line number Diff line number Diff line
@@ -683,9 +683,18 @@ void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags) 
{

	u8 flags = *tx_flags;



	if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE)

	if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) {

		flags |= SKBTX_HW_TSTAMP;



		/* PTP hardware clocks can provide a free running cycle counter

		 * as a time base for virtual clocks. Tell driver to use the

		 * free running cycle counter for timestamp if socket is bound

		 * to virtual clock.

		 */

		if (tsflags & SOF_TIMESTAMPING_BIND_PHC)

			flags |= SKBTX_HW_TSTAMP_USE_CYCLES;

	}



	if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)

		flags |= SKBTX_SW_TSTAMP;