[Linuxptp-devel] [PATCH v1 3/5] Introduce the Common Mean Link Delay Information TLV.

[Richard C. <ric...@gm...>]

Add a new TLV to convey link delay measurements by the Common Mean
Link Delay Service (CMLDS) (as specified in IEEE 1588/16.6.3) over the
management interface.

Co-authored-by: Andrew Zaborowski <and...@in...>
Signed-off-by: Kishen Maloor <kis...@in...>
Signed-off-by: Richard Cochran <ric...@gm...>
---
 clock.c      |  1 -
 pmc.c        |  9 +++++++++
 pmc_common.c |  1 +
 port.c       |  8 ++++++++
 port.h       |  2 ++
 tlv.c        | 14 ++++++++++++++
 tlv.h        |  6 ++++++
 7 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/clock.c b/clock.c
index 6f7722c..c999c83 100644
--- a/clock.c
+++ b/clock.c
@@ -47,7 +47,6 @@
 #include "util.h"
 
 #define N_CLOCK_PFD (N_POLLFD + 1) /* one extra per port, for the fault timer */
-#define POW2_41 ((double)(1ULL << 41))
 
 struct interface {
 	STAILQ_ENTRY(interface) list;
diff --git a/pmc.c b/pmc.c
index d18fea0..c29e3b7 100644
--- a/pmc.c
+++ b/pmc.c
@@ -169,6 +169,7 @@ static void pmc_show(struct ptp_message *msg, FILE *fp)
 	struct subscribe_events_np *sen;
 	struct port_properties_np *ppn;
 	struct port_hwclock_np *phn;
+	struct cmlds_info_np *cmlds;
 	struct timePropertiesDS *tp;
 	struct management_tlv *mgt;
 	struct time_status_np *tsn;
@@ -623,6 +624,14 @@ static void pmc_show(struct ptp_message *msg, FILE *fp)
 			pwr->networkTimeInaccuracy,
 			pwr->totalTimeInaccuracy);
 		break;
+	case MID_CMLDS_INFO_NP:
+		cmlds = (struct cmlds_info_np *) mgt->data;
+		fprintf(fp, "CMLDS_INFO_NP "
+			IFMT "meanLinkDelay           %" PRId64
+			IFMT "scaledNeighborRateRatio %" PRId32,
+			cmlds->meanLinkDelay >> 16,
+			cmlds->scaledNeighborRateRatio);
+		break;
 	case MID_LOG_ANNOUNCE_INTERVAL:
 		mtd = (struct management_tlv_datum *) mgt->data;
 		fprintf(fp, "LOG_ANNOUNCE_INTERVAL "
diff --git a/pmc_common.c b/pmc_common.c
index fca16c6..1d537f2 100644
--- a/pmc_common.c
+++ b/pmc_common.c
@@ -156,6 +156,7 @@ struct management_id idtab[] = {
 	{ "UNICAST_MASTER_TABLE_NP", MID_UNICAST_MASTER_TABLE_NP, do_get_action },
 	{ "PORT_HWCLOCK_NP", MID_PORT_HWCLOCK_NP, do_get_action },
 	{ "POWER_PROFILE_SETTINGS_NP", MID_POWER_PROFILE_SETTINGS_NP, do_set_action },
+	{ "CMLDS_INFO_NP", MID_CMLDS_INFO_NP, do_get_action },
 };
 
 static void do_get_action(struct pmc *pmc, int action, int index, char *str)
diff --git a/port.c b/port.c
index 136d036..aab9d3f 100644
--- a/port.c
+++ b/port.c
@@ -883,6 +883,7 @@ static int port_management_fill_response(struct port *target,
 	struct clock_description *desc;
 	struct port_properties_np *ppn;
 	struct port_hwclock_np *phn;
+	struct cmlds_info_np *cmlds;
 	struct management_tlv *tlv;
 	struct port_stats_np *psn;
 	struct foreign_clock *fc;
@@ -1125,6 +1126,13 @@ static int port_management_fill_response(struct port *target,
 		memcpy(pwr, &target->pwr, sizeof(*pwr));
 		datalen = sizeof(*pwr);
 		break;
+	case MID_CMLDS_INFO_NP:
+		cmlds = (struct cmlds_info_np *)tlv->data;
+		cmlds->meanLinkDelay = target->peerMeanPathDelay;
+		cmlds->scaledNeighborRateRatio =
+			(Integer32) (target->nrate.ratio * POW2_41 - POW2_41);
+		datalen = sizeof(*cmlds);
+		break;
 	default:
 		/* The caller should *not* respond to this message. */
 		tlv_extra_recycle(extra);
diff --git a/port.h b/port.h
index 57c8c2f..cc03859 100644
--- a/port.h
+++ b/port.h
@@ -26,6 +26,8 @@
 #include "notification.h"
 #include "transport.h"
 
+#define POW2_41 ((double)(1ULL << 41))
+
 /* forward declarations */
 struct interface;
 struct clock;
diff --git a/tlv.c b/tlv.c
index 9b82bd9..8fbeb1a 100644
--- a/tlv.c
+++ b/tlv.c
@@ -176,6 +176,7 @@ static int mgt_post_recv(struct management_tlv *m, uint16_t data_len,
 	struct port_properties_np *ppn;
 	struct port_hwclock_np *phn;
 	struct timePropertiesDS *tp;
+	struct cmlds_info_np *cmlds;
 	struct time_status_np *tsn;
 	struct port_stats_np *psn;
 	int extra_len = 0, i, len;
@@ -481,6 +482,13 @@ static int mgt_post_recv(struct management_tlv *m, uint16_t data_len,
 		NTOHL(pwr->networkTimeInaccuracy);
 		NTOHL(pwr->totalTimeInaccuracy);
 		break;
+	case MID_CMLDS_INFO_NP:
+		if (data_len < sizeof(struct cmlds_info_np))
+			goto bad_length;
+		cmlds = (struct cmlds_info_np *)m->data;
+		net2host64_unaligned(&cmlds->meanLinkDelay);
+		NTOHL(cmlds->scaledNeighborRateRatio);
+		break;
 	case MID_SAVE_IN_NON_VOLATILE_STORAGE:
 	case MID_RESET_NON_VOLATILE_STORAGE:
 	case MID_INITIALIZE:
@@ -514,6 +522,7 @@ static void mgt_pre_send(struct management_tlv *m, struct tlv_extra *extra)
 	struct subscribe_events_np *sen;
 	struct port_properties_np *ppn;
 	struct port_hwclock_np *phn;
+	struct cmlds_info_np *cmlds;
 	struct timePropertiesDS *tp;
 	struct time_status_np *tsn;
 	struct port_stats_np *psn;
@@ -672,6 +681,11 @@ static void mgt_pre_send(struct management_tlv *m, struct tlv_extra *extra)
 		HTONL(pwr->networkTimeInaccuracy);
 		HTONL(pwr->totalTimeInaccuracy);
 		break;
+	case MID_CMLDS_INFO_NP:
+		cmlds = (struct cmlds_info_np *)m->data;
+		host2net64_unaligned(&cmlds->meanLinkDelay);
+		HTONL(cmlds->scaledNeighborRateRatio);
+		break;
 	}
 }
 
diff --git a/tlv.h b/tlv.h
index 8b51ffd..6287333 100644
--- a/tlv.h
+++ b/tlv.h
@@ -129,6 +129,7 @@ enum management_action {
 #define MID_UNICAST_MASTER_TABLE_NP			0xC008
 #define MID_PORT_HWCLOCK_NP				0xC009
 #define MID_POWER_PROFILE_SETTINGS_NP			0xC00A
+#define MID_CMLDS_INFO_NP				0xC00B
 
 /* Management error ID values */
 #define MID_RESPONSE_TOO_BIG				0x0001
@@ -323,6 +324,11 @@ typedef struct Integer96 {
 	uint16_t fractional_nanoseconds;
 } PACKED ScaledNs;
 
+struct cmlds_info_np {
+	TimeInterval meanLinkDelay;
+	Integer32    scaledNeighborRateRatio;
+} PACKED;
+
 struct follow_up_info_tlv {
 	Enumeration16 type;
 	UInteger16    length;
-- 
2.39.2