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
tt560_start(int unit,struct peer * peer)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
tt560_shutdown(int unit,struct peer * peer)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
tt560_poll(int unit,struct peer * peer)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
byte_swap(unsigned int input_num)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