linuxptp/fsm.c
Yangbo Lu f8ffb2cf5a Add BMCA support for IEEE 802.1AS-2011
According to IEEE 802.1AS-2011, the BMCA used in gPTP is the same
as that used in IEEE 1588 with the following exceptions:

(1) Announce messages received on a slave port that were not sent
by the receiving time-aware system are used immediately,
i.e., there is no foreign-master qualification.

(2) A port that the BMCA determines should be a master port enters
the master state immediately, i.e., there is no pre-master state.

(3) The uncalibrated state is not needed and, therefore, not used.

(4) All time-aware systems are required to participate in best master
selection (even if it is not grandmaster capable).

This patch is to support (1) by using a specific FOREIGN_MASTER_THRESHOLD
case. (Treat FOREIGN_MASTER_THRESHOLD as 1.)
To support (2) and (3), reuse ptp_fsm and drop pre-master/uncalibrated
states. The (4) item is supported since IEEE 802.1AS reuses OC/BC.

Signed-off-by: Erik Hons <erik.hons@ni.com>
Signed-off-by: Rodney Greenstreet <rodney.greenstreet@ni.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
2020-08-30 00:26:30 +03:00

351 lines
6.5 KiB
C

/**
* @file fsm.c
* @note Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "fsm.h"
enum port_state ptp_fsm(enum port_state state, enum fsm_event event, int mdiff)
{
enum port_state next = state;
if (EV_INITIALIZE == event || EV_POWERUP == event)
return PS_INITIALIZING;
switch (state) {
case PS_INITIALIZING:
switch (event) {
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_INIT_COMPLETE:
next = PS_LISTENING;
break;
default:
break;
}
break;
case PS_FAULTY:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_CLEARED:
next = PS_INITIALIZING;
break;
default:
break;
}
break;
case PS_DISABLED:
if (EV_DESIGNATED_ENABLED == event)
next = PS_INITIALIZING;
break;
case PS_LISTENING:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
next = PS_MASTER;
break;
case EV_RS_MASTER:
next = PS_PRE_MASTER;
break;
case EV_RS_GRAND_MASTER:
next = PS_GRAND_MASTER;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
case EV_RS_PASSIVE:
next = PS_PASSIVE;
break;
default:
break;
}
break;
case PS_PRE_MASTER:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_QUALIFICATION_TIMEOUT_EXPIRES:
next = PS_MASTER;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
case EV_RS_PASSIVE:
next = PS_PASSIVE;
break;
default:
break;
}
break;
case PS_MASTER:
case PS_GRAND_MASTER:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
case EV_RS_PASSIVE:
next = PS_PASSIVE;
break;
default:
break;
}
break;
case PS_PASSIVE:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
next = PS_MASTER;
break;
case EV_RS_MASTER:
next = PS_PRE_MASTER;
break;
case EV_RS_GRAND_MASTER:
next = PS_GRAND_MASTER;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
default:
break;
}
break;
case PS_UNCALIBRATED:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
next = PS_MASTER;
break;
case EV_MASTER_CLOCK_SELECTED:
next = PS_SLAVE;
break;
case EV_RS_MASTER:
next = PS_PRE_MASTER;
break;
case EV_RS_GRAND_MASTER:
next = PS_GRAND_MASTER;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
case EV_RS_PASSIVE:
next = PS_PASSIVE;
break;
default:
break;
}
break;
case PS_SLAVE:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
next = PS_MASTER;
break;
case EV_SYNCHRONIZATION_FAULT:
next = PS_UNCALIBRATED;
break;
case EV_RS_MASTER:
next = PS_PRE_MASTER;
break;
case EV_RS_GRAND_MASTER:
next = PS_GRAND_MASTER;
break;
case EV_RS_SLAVE:
if (mdiff)
next = PS_UNCALIBRATED;
break;
case EV_RS_PASSIVE:
next = PS_PASSIVE;
break;
default:
break;
}
break;
}
return next;
}
enum port_state ptp_slave_fsm(enum port_state state, enum fsm_event event,
int mdiff)
{
enum port_state next = state;
if (EV_INITIALIZE == event || EV_POWERUP == event)
return PS_INITIALIZING;
switch (state) {
case PS_INITIALIZING:
switch (event) {
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_INIT_COMPLETE:
next = PS_LISTENING;
break;
default:
break;
}
break;
case PS_FAULTY:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_CLEARED:
next = PS_INITIALIZING;
break;
default:
break;
}
break;
case PS_DISABLED:
if (EV_DESIGNATED_ENABLED == event)
next = PS_INITIALIZING;
break;
case PS_LISTENING:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
case EV_RS_MASTER:
case EV_RS_GRAND_MASTER:
case EV_RS_PASSIVE:
next = PS_LISTENING;
break;
case EV_RS_SLAVE:
next = PS_UNCALIBRATED;
break;
default:
break;
}
break;
case PS_UNCALIBRATED:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
case EV_RS_MASTER:
case EV_RS_GRAND_MASTER:
case EV_RS_PASSIVE:
next = PS_LISTENING;
break;
case EV_MASTER_CLOCK_SELECTED:
next = PS_SLAVE;
break;
default:
break;
}
break;
case PS_SLAVE:
switch (event) {
case EV_DESIGNATED_DISABLED:
next = PS_DISABLED;
break;
case EV_FAULT_DETECTED:
next = PS_FAULTY;
break;
case EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES:
case EV_RS_MASTER:
case EV_RS_GRAND_MASTER:
case EV_RS_PASSIVE:
next = PS_LISTENING;
break;
case EV_SYNCHRONIZATION_FAULT:
next = PS_UNCALIBRATED;
break;
case EV_RS_SLAVE:
if (mdiff)
next = PS_UNCALIBRATED;
break;
default:
break;
}
break;
default:
break;
}
return next;
}
enum port_state ieee8021as_fsm(enum port_state state, enum fsm_event event,
int mdiff)
{
enum port_state next = ptp_fsm(state, event, mdiff);
if (next == PS_UNCALIBRATED)
return PS_SLAVE;
if (next == PS_PRE_MASTER)
return PS_MASTER;
return next;
}