xref: /linux/samples/timers/hpet_example.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <fcntl.h>
5 #include <string.h>
6 #include <memory.h>
7 #include <malloc.h>
8 #include <time.h>
9 #include <ctype.h>
10 #include <sys/types.h>
11 #include <sys/wait.h>
12 #include <signal.h>
13 #include <errno.h>
14 #include <sys/time.h>
15 #include <linux/hpet.h>
16 
17 
18 extern void hpet_open_close(int, const char **);
19 extern void hpet_info(int, const char **);
20 extern void hpet_poll(int, const char **);
21 extern void hpet_fasync(int, const char **);
22 extern void hpet_read(int, const char **);
23 
24 #include <sys/poll.h>
25 #include <sys/ioctl.h>
26 
27 struct hpet_command {
28 	char		*command;
29 	void		(*func)(int argc, const char ** argv);
30 } hpet_command[] = {
31 	{
32 		"open-close",
33 		hpet_open_close
34 	},
35 	{
36 		"info",
37 		hpet_info
38 	},
39 	{
40 		"poll",
41 		hpet_poll
42 	},
43 	{
44 		"fasync",
45 		hpet_fasync
46 	},
47 };
48 
49 int
50 main(int argc, const char ** argv)
51 {
52 	unsigned int	i;
53 
54 	argc--;
55 	argv++;
56 
57 	if (!argc) {
58 		fprintf(stderr, "-hpet: requires command\n");
59 		return -1;
60 	}
61 
62 
63 	for (i = 0; i < (sizeof (hpet_command) / sizeof (hpet_command[0])); i++)
64 		if (!strcmp(argv[0], hpet_command[i].command)) {
65 			argc--;
66 			argv++;
67 			fprintf(stderr, "-hpet: executing %s\n",
68 				hpet_command[i].command);
69 			hpet_command[i].func(argc, argv);
70 			return 0;
71 		}
72 
73 	fprintf(stderr, "do_hpet: command %s not implemented\n", argv[0]);
74 
75 	return -1;
76 }
77 
78 void
79 hpet_open_close(int argc, const char **argv)
80 {
81 	int	fd;
82 
83 	if (argc != 1) {
84 		fprintf(stderr, "hpet_open_close: device-name\n");
85 		return;
86 	}
87 
88 	fd = open(argv[0], O_RDONLY);
89 	if (fd < 0)
90 		fprintf(stderr, "hpet_open_close: open failed\n");
91 	else
92 		close(fd);
93 
94 	return;
95 }
96 
97 void
98 hpet_info(int argc, const char **argv)
99 {
100 	struct hpet_info	info;
101 	int			fd;
102 
103 	if (argc != 1) {
104 		fprintf(stderr, "hpet_info: device-name\n");
105 		return;
106 	}
107 
108 	fd = open(argv[0], O_RDONLY);
109 	if (fd < 0) {
110 		fprintf(stderr, "hpet_info: open of %s failed\n", argv[0]);
111 		return;
112 	}
113 
114 	if (ioctl(fd, HPET_INFO, &info) < 0) {
115 		fprintf(stderr, "hpet_info: failed to get info\n");
116 		goto out;
117 	}
118 
119 	fprintf(stderr, "hpet_info: hi_irqfreq 0x%lx hi_flags 0x%lx ",
120 		info.hi_ireqfreq, info.hi_flags);
121 	fprintf(stderr, "hi_hpet %d hi_timer %d\n",
122 		info.hi_hpet, info.hi_timer);
123 
124 out:
125 	close(fd);
126 	return;
127 }
128 
129 void
130 hpet_poll(int argc, const char **argv)
131 {
132 	unsigned long		freq;
133 	int			iterations, i, fd;
134 	struct pollfd		pfd;
135 	struct hpet_info	info;
136 	struct timeval		stv, etv;
137 	struct timezone		tz;
138 	long			usec;
139 
140 	if (argc != 3) {
141 		fprintf(stderr, "hpet_poll: device-name freq iterations\n");
142 		return;
143 	}
144 
145 	freq = atoi(argv[1]);
146 	iterations = atoi(argv[2]);
147 
148 	fd = open(argv[0], O_RDONLY);
149 
150 	if (fd < 0) {
151 		fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
152 		return;
153 	}
154 
155 	if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
156 		fprintf(stderr, "hpet_poll: HPET_IRQFREQ failed\n");
157 		goto out;
158 	}
159 
160 	if (ioctl(fd, HPET_INFO, &info) < 0) {
161 		fprintf(stderr, "hpet_poll: failed to get info\n");
162 		goto out;
163 	}
164 
165 	fprintf(stderr, "hpet_poll: info.hi_flags 0x%lx\n", info.hi_flags);
166 
167 	if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
168 		fprintf(stderr, "hpet_poll: HPET_EPI failed\n");
169 		goto out;
170 	}
171 
172 	if (ioctl(fd, HPET_IE_ON, 0) < 0) {
173 		fprintf(stderr, "hpet_poll, HPET_IE_ON failed\n");
174 		goto out;
175 	}
176 
177 	pfd.fd = fd;
178 	pfd.events = POLLIN;
179 
180 	for (i = 0; i < iterations; i++) {
181 		pfd.revents = 0;
182 		gettimeofday(&stv, &tz);
183 		if (poll(&pfd, 1, -1) < 0)
184 			fprintf(stderr, "hpet_poll: poll failed\n");
185 		else {
186 			long 	data;
187 
188 			gettimeofday(&etv, &tz);
189 			usec = stv.tv_sec * 1000000 + stv.tv_usec;
190 			usec = (etv.tv_sec * 1000000 + etv.tv_usec) - usec;
191 
192 			fprintf(stderr,
193 				"hpet_poll: expired time = 0x%lx\n", usec);
194 
195 			fprintf(stderr, "hpet_poll: revents = 0x%x\n",
196 				pfd.revents);
197 
198 			if (read(fd, &data, sizeof(data)) != sizeof(data)) {
199 				fprintf(stderr, "hpet_poll: read failed\n");
200 			}
201 			else
202 				fprintf(stderr, "hpet_poll: data 0x%lx\n",
203 					data);
204 		}
205 	}
206 
207 out:
208 	close(fd);
209 	return;
210 }
211 
212 static int hpet_sigio_count;
213 
214 static void
215 hpet_sigio(int val)
216 {
217 	fprintf(stderr, "hpet_sigio: called\n");
218 	hpet_sigio_count++;
219 }
220 
221 void
222 hpet_fasync(int argc, const char **argv)
223 {
224 	unsigned long		freq;
225 	int			iterations, i, fd, value;
226 	sig_t			oldsig;
227 	struct hpet_info	info;
228 
229 	hpet_sigio_count = 0;
230 	fd = -1;
231 
232 	if ((oldsig = signal(SIGIO, hpet_sigio)) == SIG_ERR) {
233 		fprintf(stderr, "hpet_fasync: failed to set signal handler\n");
234 		return;
235 	}
236 
237 	if (argc != 3) {
238 		fprintf(stderr, "hpet_fasync: device-name freq iterations\n");
239 		goto out;
240 	}
241 
242 	fd = open(argv[0], O_RDONLY);
243 
244 	if (fd < 0) {
245 		fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);
246 		return;
247 	}
248 
249 
250 	if ((fcntl(fd, F_SETOWN, getpid()) == 1) ||
251 		((value = fcntl(fd, F_GETFL)) == 1) ||
252 		(fcntl(fd, F_SETFL, value | O_ASYNC) == 1)) {
253 		fprintf(stderr, "hpet_fasync: fcntl failed\n");
254 		goto out;
255 	}
256 
257 	freq = atoi(argv[1]);
258 	iterations = atoi(argv[2]);
259 
260 	if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
261 		fprintf(stderr, "hpet_fasync: HPET_IRQFREQ failed\n");
262 		goto out;
263 	}
264 
265 	if (ioctl(fd, HPET_INFO, &info) < 0) {
266 		fprintf(stderr, "hpet_fasync: failed to get info\n");
267 		goto out;
268 	}
269 
270 	fprintf(stderr, "hpet_fasync: info.hi_flags 0x%lx\n", info.hi_flags);
271 
272 	if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
273 		fprintf(stderr, "hpet_fasync: HPET_EPI failed\n");
274 		goto out;
275 	}
276 
277 	if (ioctl(fd, HPET_IE_ON, 0) < 0) {
278 		fprintf(stderr, "hpet_fasync, HPET_IE_ON failed\n");
279 		goto out;
280 	}
281 
282 	for (i = 0; i < iterations; i++) {
283 		(void) pause();
284 		fprintf(stderr, "hpet_fasync: count = %d\n", hpet_sigio_count);
285 	}
286 
287 out:
288 	signal(SIGIO, oldsig);
289 
290 	if (fd >= 0)
291 		close(fd);
292 
293 	return;
294 }
295