1 /*- 2 * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification, immediately at the beginning of the file. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/kernel.h> 32 #include <sys/sysctl.h> 33 #include <sys/systm.h> 34 #include <sys/queue.h> 35 #include <sys/timeet.h> 36 37 SLIST_HEAD(et_eventtimers_list, eventtimer); 38 static struct et_eventtimers_list eventtimers = SLIST_HEAD_INITIALIZER(et_eventtimers); 39 40 struct mtx et_eventtimers_mtx; 41 MTX_SYSINIT(et_eventtimers_init, &et_eventtimers_mtx, "et_mtx", MTX_DEF); 42 43 SYSCTL_NODE(_kern, OID_AUTO, eventtimer, CTLFLAG_RW, 0, "Event timers"); 44 SYSCTL_NODE(_kern_eventtimer, OID_AUTO, et, CTLFLAG_RW, 0, ""); 45 46 /* 47 * Register a new event timer hardware. 48 */ 49 int 50 et_register(struct eventtimer *et) 51 { 52 struct eventtimer *tmp, *next; 53 54 if (et->et_quality >= 0 || bootverbose) { 55 if (et->et_frequency == 0) { 56 printf("Event timer \"%s\" quality %d\n", 57 et->et_name, et->et_quality); 58 } else { 59 printf("Event timer \"%s\" " 60 "frequency %ju Hz quality %d\n", 61 et->et_name, (uintmax_t)et->et_frequency, 62 et->et_quality); 63 } 64 } 65 et->et_sysctl = SYSCTL_ADD_NODE(NULL, 66 SYSCTL_STATIC_CHILDREN(_kern_eventtimer_et), OID_AUTO, et->et_name, 67 CTLFLAG_RW, 0, "event timer description"); 68 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, 69 "flags", CTLFLAG_RD, &(et->et_flags), 0, 70 "Event timer capabilities"); 71 SYSCTL_ADD_UQUAD(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, 72 "frequency", CTLFLAG_RD, &(et->et_frequency), 73 "Event timer base frequency"); 74 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO, 75 "quality", CTLFLAG_RD, &(et->et_quality), 0, 76 "Goodness of event timer"); 77 ET_LOCK(); 78 if (SLIST_EMPTY(&eventtimers) || 79 SLIST_FIRST(&eventtimers)->et_quality < et->et_quality) { 80 SLIST_INSERT_HEAD(&eventtimers, et, et_all); 81 } else { 82 SLIST_FOREACH(tmp, &eventtimers, et_all) { 83 next = SLIST_NEXT(tmp, et_all); 84 if (next == NULL || next->et_quality < et->et_quality) { 85 SLIST_INSERT_AFTER(tmp, et, et_all); 86 break; 87 } 88 } 89 } 90 ET_UNLOCK(); 91 return (0); 92 } 93 94 /* 95 * Deregister event timer hardware. 96 */ 97 int 98 et_deregister(struct eventtimer *et) 99 { 100 int err = 0; 101 102 if (et->et_deregister_cb != NULL) { 103 if ((err = et->et_deregister_cb(et, et->et_arg)) != 0) 104 return (err); 105 } 106 107 ET_LOCK(); 108 SLIST_REMOVE(&eventtimers, et, eventtimer, et_all); 109 ET_UNLOCK(); 110 sysctl_remove_oid(et->et_sysctl, 1, 1); 111 return (0); 112 } 113 114 /* 115 * Find free event timer hardware with specified parameters. 116 */ 117 struct eventtimer * 118 et_find(const char *name, int check, int want) 119 { 120 struct eventtimer *et = NULL; 121 122 SLIST_FOREACH(et, &eventtimers, et_all) { 123 if (et->et_active) 124 continue; 125 if (name != NULL && strcasecmp(et->et_name, name) != 0) 126 continue; 127 if (name == NULL && et->et_quality < 0) 128 continue; 129 if ((et->et_flags & check) != want) 130 continue; 131 break; 132 } 133 return (et); 134 } 135 136 /* 137 * Initialize event timer hardware. Set callbacks. 138 */ 139 int 140 et_init(struct eventtimer *et, et_event_cb_t *event, 141 et_deregister_cb_t *deregister, void *arg) 142 { 143 144 if (event == NULL) 145 return (EINVAL); 146 if (et->et_active) 147 return (EBUSY); 148 149 et->et_active = 1; 150 et->et_event_cb = event; 151 et->et_deregister_cb = deregister; 152 et->et_arg = arg; 153 return (0); 154 } 155 156 /* 157 * Start event timer hardware. 158 * first - delay before first tick. 159 * period - period of subsequent periodic ticks. 160 */ 161 int 162 et_start(struct eventtimer *et, 163 struct bintime *first, struct bintime *period) 164 { 165 166 if (!et->et_active) 167 return (ENXIO); 168 if (first == NULL && period == NULL) 169 return (EINVAL); 170 if ((et->et_flags & ET_FLAGS_PERIODIC) == 0 && 171 period != NULL) 172 return (ENODEV); 173 if ((et->et_flags & ET_FLAGS_ONESHOT) == 0 && 174 period == NULL) 175 return (ENODEV); 176 if (first != NULL) { 177 if (first->sec < et->et_min_period.sec || 178 (first->sec == et->et_min_period.sec && 179 first->frac < et->et_min_period.frac)) 180 first = &et->et_min_period; 181 if (first->sec > et->et_max_period.sec || 182 (first->sec == et->et_max_period.sec && 183 first->frac > et->et_max_period.frac)) 184 first = &et->et_max_period; 185 } 186 if (period != NULL) { 187 if (period->sec < et->et_min_period.sec || 188 (period->sec == et->et_min_period.sec && 189 period->frac < et->et_min_period.frac)) 190 period = &et->et_min_period; 191 if (period->sec > et->et_max_period.sec || 192 (period->sec == et->et_max_period.sec && 193 period->frac > et->et_max_period.frac)) 194 period = &et->et_max_period; 195 } 196 if (et->et_start) 197 return (et->et_start(et, first, period)); 198 return (0); 199 } 200 201 /* Stop event timer hardware. */ 202 int 203 et_stop(struct eventtimer *et) 204 { 205 206 if (!et->et_active) 207 return (ENXIO); 208 if (et->et_stop) 209 return (et->et_stop(et)); 210 return (0); 211 } 212 213 /* Mark event timer hardware as broken. */ 214 int 215 et_ban(struct eventtimer *et) 216 { 217 218 et->et_flags &= ~(ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT); 219 return (0); 220 } 221 222 /* Free event timer hardware. */ 223 int 224 et_free(struct eventtimer *et) 225 { 226 227 if (!et->et_active) 228 return (ENXIO); 229 230 et->et_active = 0; 231 return (0); 232 } 233 234 /* Report list of supported event timers hardware via sysctl. */ 235 static int 236 sysctl_kern_eventtimer_choice(SYSCTL_HANDLER_ARGS) 237 { 238 char buf[512], *spc; 239 struct eventtimer *et; 240 int error, off; 241 242 spc = ""; 243 error = 0; 244 buf[0] = 0; 245 off = 0; 246 ET_LOCK(); 247 SLIST_FOREACH(et, &eventtimers, et_all) { 248 off += snprintf(buf + off, sizeof(buf) - off, "%s%s(%d)", 249 spc, et->et_name, et->et_quality); 250 spc = " "; 251 } 252 ET_UNLOCK(); 253 error = SYSCTL_OUT(req, buf, strlen(buf)); 254 return (error); 255 } 256 SYSCTL_PROC(_kern_eventtimer, OID_AUTO, choice, 257 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 258 0, 0, sysctl_kern_eventtimer_choice, "A", "Present event timers"); 259 260