xref: /freebsd/contrib/ntp/ntpd/refclock_tt560.c (revision f5f40dd63bc7acbb5312b26ac1ea1103c12352a6)
1 /*
2  * refclock_tt560 - clock driver for the TrueTime 560 IRIG-B decoder
3  */
4 
5 #ifdef HAVE_CONFIG_H
6 #include <config.h>
7 #endif
8 
9 #if defined(REFCLOCK) && defined(CLOCK_TT560)
10 
11 #include "ntpd.h"
12 #include "ntp_io.h"
13 #include "ntp_refclock.h"
14 #include "ntp_unixtime.h"
15 #include "sys/tt560_api.h"
16 #include "ntp_stdlib.h"
17 
18 #include <stdio.h>
19 #include <ctype.h>
20 
21 /*
22  * This driver supports the TrueTime 560 IRIG-B decoder for the PCI bus.
23  */
24 
25 /*
26  * TT560 interface definitions
27  */
28 #define	DEVICE		 "/dev/tt560%d" /* device name and unit */
29 #define	PRECISION	(-20)	/* precision assumed (1 us) */
30 #define	REFID		"IRIG"	/* reference ID */
31 #define	DESCRIPTION	"TrueTime 560 IRIG-B PCI Decoder"
32 
33 /*
34  * Unit control structure
35  */
36 struct tt560unit {
37 	tt_mem_space_t	 *tt_mem;	/* mapped address of PCI board */
38 	time_freeze_reg_t tt560rawt;	/* data returned from PCI board */
39 };
40 
41 typedef union byteswap_u
42 {
43     unsigned int long_word;
44     unsigned char byte[4];
45 } byteswap_t;
46 
47 /*
48  * Function prototypes
49  */
50 static	int	tt560_start	(int, struct peer *);
51 static	void	tt560_shutdown	(int, struct peer *);
52 static	void	tt560_poll	(int unit, struct peer *);
53 
54 /*
55  * Transfer vector
56  */
57 struct	refclock refclock_tt560 = {
58 	tt560_start,		/* clock_start    */
59 	tt560_shutdown,		/* clock_shutdown */
60 	tt560_poll,		/* clock_poll     */
61 	noentry,		/* clock_control (not used) */
62 	noentry,		/* clock_init    (not used) */
63 	noentry,		/* clock_buginfo (not used) */
64 	NOFLAGS			/* clock_flags   (not used) */
65 };
66 
67 
68 /*
69  * tt560_start - open the TT560 device and initialize data for processing
70  */
71 static int
72 tt560_start(
73 	int unit,
74 	struct peer *peer
75 	)
76 {
77 	register struct tt560unit *up;
78 	struct refclockproc *pp;
79 	char	device[20];
80 	int	fd;
81 	caddr_t membase;
82 
83 	/*
84 	 * Open TT560 device
85 	 */
86 	snprintf(device, sizeof(device), DEVICE, unit);
87 	fd = open(device, O_RDWR);
88 	if (fd == -1) {
89 		msyslog(LOG_ERR, "tt560_start: open of %s: %m", device);
90 		return (0);
91 	}
92 
93 	/*
94 	 * Map the device registers into user space.
95 	 */
96 	membase = mmap ((caddr_t) 0, TTIME_MEMORY_SIZE,
97 			PROT_READ | PROT_WRITE,
98 			MAP_SHARED, fd, (off_t)0);
99 
100 	if (membase == (caddr_t) -1) {
101 		msyslog(LOG_ERR, "tt560_start: mapping of %s: %m", device);
102 		(void) close(fd);
103 		return (0);
104 	}
105 
106 	/*
107 	 * Allocate and initialize unit structure
108 	 */
109 	if (!(up = (struct tt560unit *) emalloc(sizeof(struct tt560unit)))) {
110 		(void) close(fd);
111 		return (0);
112 	}
113 	memset((char *)up, 0, sizeof(struct tt560unit));
114 	up->tt_mem = (tt_mem_space_t *)membase;
115 	pp = peer->procptr;
116 	pp->io.clock_recv = noentry;
117 	pp->io.srcclock = (caddr_t)peer;
118 	pp->io.datalen = 0;
119 	pp->io.fd = fd;
120 	pp->unitptr = (caddr_t)up;
121 
122 	/*
123 	 * Initialize miscellaneous peer variables
124 	 */
125 	peer->precision = PRECISION;
126 	pp->clockdesc = DESCRIPTION;
127 	memcpy((char *)&pp->refid, REFID, 4);
128 	return (1);
129 }
130 
131 
132 /*
133  * tt560_shutdown - shut down the clock
134  */
135 static void
136 tt560_shutdown(
137 	int unit,
138 	struct peer *peer
139 	)
140 {
141 	register struct tt560unit *up;
142 	struct refclockproc *pp;
143 
144 	pp = peer->procptr;
145 	up = (struct tt560unit *)pp->unitptr;
146 	io_closeclock(&pp->io);
147 	free(up);
148 }
149 
150 
151 /*
152  * tt560_poll - called by the transmit procedure
153  */
154 static void
155 tt560_poll(
156 	int unit,
157 	struct peer *peer
158 	)
159 {
160 	register struct tt560unit *up;
161 	struct refclockproc       *pp;
162 	time_freeze_reg_t         *tp;
163 	tt_mem_space_t            *mp;
164 
165 	int i;
166 	unsigned int *p_time_t, *tt_mem_t;
167 
168 	/*
169 	 * This is the main routine. It snatches the time from the TT560
170 	 * board and tacks on a local timestamp.
171 	 */
172 	pp = peer->procptr;
173 	up = (struct tt560unit *)pp->unitptr;
174 	mp = up->tt_mem;
175 	tp = &up->tt560rawt;
176 
177 	p_time_t = (unsigned int *)tp;
178 	tt_mem_t = (unsigned int *)&mp->time_freeze_reg;
179 
180 	*tt_mem_t = 0;		/* update the time freeze register */
181 				/* and copy time stamp to memory */
182 	for (i=0; i < TIME_FREEZE_REG_LEN; i++) {
183 	    *p_time_t = byte_swap(*tt_mem_t);
184 	     p_time_t++;
185 	     tt_mem_t++;
186 	}
187 
188 	get_systime(&pp->lastrec);
189 	pp->polls++;
190 
191 	/*
192 	 * We get down to business, check the timecode format and decode
193 	 * its contents. If the timecode has invalid length or is not in
194 	 * proper format, we declare bad format and exit. Note: we
195 	 * can't use the sec/usec conversion produced by the driver,
196 	 * since the year may be suspect. All format error checking is
197 	 * done by the snprintf() and sscanf() routines.
198 	 */
199 	snprintf(pp->a_lastcode, sizeof(pp->a_lastcode),
200 	    "%1x%1x%1x %1x%1x:%1x%1x:%1x%1x.%1x%1x%1x%1x%1x%1x %1x",
201 	    tp->hun_day,  tp->tens_day,  tp->unit_day,
202 	                  tp->tens_hour, tp->unit_hour,
203 	                  tp->tens_min,  tp->unit_min,
204 	                  tp->tens_sec,  tp->unit_sec,
205 	    tp->hun_ms,   tp->tens_ms,   tp->unit_ms,
206 	    tp->hun_us,   tp->tens_us,   tp->unit_us,
207 	    tp->status);
208 	    pp->lencode = strlen(pp->a_lastcode);
209 #ifdef DEBUG
210 	if (debug)
211 		printf("tt560: time %s timecode %d %s\n",
212 		   ulfptoa(&pp->lastrec, 6), pp->lencode,
213 		   pp->a_lastcode);
214 #endif
215 	if (sscanf(pp->a_lastcode, "%3d %2d:%2d:%2d.%6ld",
216                   &pp->day, &pp->hour, &pp->minute, &pp->second, &pp->usec)
217 	    != 5) {
218 		refclock_report(peer, CEVNT_BADTIME);
219 		return;
220 	}
221 	if ((tp->status & 0x6) != 0x6)
222 		pp->leap = LEAP_NOTINSYNC;
223 	else
224 		pp->leap = LEAP_NOWARNING;
225 	if (!refclock_process(pp)) {
226 		refclock_report(peer, CEVNT_BADTIME);
227 		return;
228 	}
229 	if (pp->coderecv == pp->codeproc) {
230 		refclock_report(peer, CEVNT_TIMEOUT);
231 		return;
232 	}
233 	record_clock_stats(&peer->srcadr, pp->a_lastcode);
234 	refclock_receive(peer);
235 }
236 
237 /******************************************************************
238  *
239  *  byte_swap
240  *
241  *  Inputs: 32 bit integer
242  *
243  *  Output: byte swapped 32 bit integer.
244  *
245  *  This routine is used to compensate for the byte alignment
246  *  differences between big-endian and little-endian integers.
247  *
248  ******************************************************************/
249 static unsigned int
250 byte_swap(unsigned int input_num)
251 {
252     byteswap_t    byte_swap;
253     unsigned char temp;
254 
255     byte_swap.long_word = input_num;
256 
257     temp              = byte_swap.byte[3];
258     byte_swap.byte[3] = byte_swap.byte[0];
259     byte_swap.byte[0] = temp;
260 
261     temp              = byte_swap.byte[2];
262     byte_swap.byte[2] = byte_swap.byte[1];
263     byte_swap.byte[1] = temp;
264 
265     return (byte_swap.long_word);
266 }
267 
268 #else
269 NONEMPTY_TRANSLATION_UNIT
270 #endif /* REFCLOCK */
271