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-rw-r--r--sys/kern/kern_et.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/sys/kern/kern_et.c b/sys/kern/kern_et.c
new file mode 100644
index 0000000..3156c81
--- /dev/null
+++ b/sys/kern/kern_et.c
@@ -0,0 +1,259 @@
+/*-
+ * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer,
+ * without modification, immediately at the beginning of the file.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/sysctl.h>
+#include <sys/systm.h>
+#include <sys/queue.h>
+#include <sys/timeet.h>
+
+SLIST_HEAD(et_eventtimers_list, eventtimer);
+static struct et_eventtimers_list eventtimers = SLIST_HEAD_INITIALIZER(et_eventtimers);
+
+struct mtx et_eventtimers_mtx;
+MTX_SYSINIT(et_eventtimers_init, &et_eventtimers_mtx, "et_mtx", MTX_DEF);
+
+SYSCTL_NODE(_kern, OID_AUTO, eventtimer, CTLFLAG_RW, 0, "Event timers");
+static SYSCTL_NODE(_kern_eventtimer, OID_AUTO, et, CTLFLAG_RW, 0, "");
+
+/*
+ * Register a new event timer hardware.
+ */
+int
+et_register(struct eventtimer *et)
+{
+ struct eventtimer *tmp, *next;
+
+ if (et->et_quality >= 0 || bootverbose) {
+ if (et->et_frequency == 0) {
+ printf("Event timer \"%s\" quality %d\n",
+ et->et_name, et->et_quality);
+ } else {
+ printf("Event timer \"%s\" "
+ "frequency %ju Hz quality %d\n",
+ et->et_name, (uintmax_t)et->et_frequency,
+ et->et_quality);
+ }
+ }
+ et->et_sysctl = SYSCTL_ADD_NODE(NULL,
+ SYSCTL_STATIC_CHILDREN(_kern_eventtimer_et), OID_AUTO, et->et_name,
+ CTLFLAG_RW, 0, "event timer description");
+ SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO,
+ "flags", CTLFLAG_RD, &(et->et_flags), 0,
+ "Event timer capabilities");
+ SYSCTL_ADD_UQUAD(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO,
+ "frequency", CTLFLAG_RD, &(et->et_frequency),
+ "Event timer base frequency");
+ SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(et->et_sysctl), OID_AUTO,
+ "quality", CTLFLAG_RD, &(et->et_quality), 0,
+ "Goodness of event timer");
+ ET_LOCK();
+ if (SLIST_EMPTY(&eventtimers) ||
+ SLIST_FIRST(&eventtimers)->et_quality < et->et_quality) {
+ SLIST_INSERT_HEAD(&eventtimers, et, et_all);
+ } else {
+ SLIST_FOREACH(tmp, &eventtimers, et_all) {
+ next = SLIST_NEXT(tmp, et_all);
+ if (next == NULL || next->et_quality < et->et_quality) {
+ SLIST_INSERT_AFTER(tmp, et, et_all);
+ break;
+ }
+ }
+ }
+ ET_UNLOCK();
+ return (0);
+}
+
+/*
+ * Deregister event timer hardware.
+ */
+int
+et_deregister(struct eventtimer *et)
+{
+ int err = 0;
+
+ if (et->et_deregister_cb != NULL) {
+ if ((err = et->et_deregister_cb(et, et->et_arg)) != 0)
+ return (err);
+ }
+
+ ET_LOCK();
+ SLIST_REMOVE(&eventtimers, et, eventtimer, et_all);
+ ET_UNLOCK();
+ sysctl_remove_oid(et->et_sysctl, 1, 1);
+ return (0);
+}
+
+/*
+ * Find free event timer hardware with specified parameters.
+ */
+struct eventtimer *
+et_find(const char *name, int check, int want)
+{
+ struct eventtimer *et = NULL;
+
+ SLIST_FOREACH(et, &eventtimers, et_all) {
+ if (et->et_active)
+ continue;
+ if (name != NULL && strcasecmp(et->et_name, name) != 0)
+ continue;
+ if (name == NULL && et->et_quality < 0)
+ continue;
+ if ((et->et_flags & check) != want)
+ continue;
+ break;
+ }
+ return (et);
+}
+
+/*
+ * Initialize event timer hardware. Set callbacks.
+ */
+int
+et_init(struct eventtimer *et, et_event_cb_t *event,
+ et_deregister_cb_t *deregister, void *arg)
+{
+
+ if (event == NULL)
+ return (EINVAL);
+ if (et->et_active)
+ return (EBUSY);
+
+ et->et_active = 1;
+ et->et_event_cb = event;
+ et->et_deregister_cb = deregister;
+ et->et_arg = arg;
+ return (0);
+}
+
+/*
+ * Start event timer hardware.
+ * first - delay before first tick.
+ * period - period of subsequent periodic ticks.
+ */
+int
+et_start(struct eventtimer *et,
+ struct bintime *first, struct bintime *period)
+{
+
+ if (!et->et_active)
+ return (ENXIO);
+ if (first == NULL && period == NULL)
+ return (EINVAL);
+ if ((et->et_flags & ET_FLAGS_PERIODIC) == 0 &&
+ period != NULL)
+ return (ENODEV);
+ if ((et->et_flags & ET_FLAGS_ONESHOT) == 0 &&
+ period == NULL)
+ return (ENODEV);
+ if (first != NULL) {
+ if (first->sec < et->et_min_period.sec ||
+ (first->sec == et->et_min_period.sec &&
+ first->frac < et->et_min_period.frac))
+ first = &et->et_min_period;
+ if (first->sec > et->et_max_period.sec ||
+ (first->sec == et->et_max_period.sec &&
+ first->frac > et->et_max_period.frac))
+ first = &et->et_max_period;
+ }
+ if (period != NULL) {
+ if (period->sec < et->et_min_period.sec ||
+ (period->sec == et->et_min_period.sec &&
+ period->frac < et->et_min_period.frac))
+ period = &et->et_min_period;
+ if (period->sec > et->et_max_period.sec ||
+ (period->sec == et->et_max_period.sec &&
+ period->frac > et->et_max_period.frac))
+ period = &et->et_max_period;
+ }
+ if (et->et_start)
+ return (et->et_start(et, first, period));
+ return (0);
+}
+
+/* Stop event timer hardware. */
+int
+et_stop(struct eventtimer *et)
+{
+
+ if (!et->et_active)
+ return (ENXIO);
+ if (et->et_stop)
+ return (et->et_stop(et));
+ return (0);
+}
+
+/* Mark event timer hardware as broken. */
+int
+et_ban(struct eventtimer *et)
+{
+
+ et->et_flags &= ~(ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT);
+ return (0);
+}
+
+/* Free event timer hardware. */
+int
+et_free(struct eventtimer *et)
+{
+
+ if (!et->et_active)
+ return (ENXIO);
+
+ et->et_active = 0;
+ return (0);
+}
+
+/* Report list of supported event timers hardware via sysctl. */
+static int
+sysctl_kern_eventtimer_choice(SYSCTL_HANDLER_ARGS)
+{
+ char buf[512], *spc;
+ struct eventtimer *et;
+ int error, off;
+
+ spc = "";
+ error = 0;
+ buf[0] = 0;
+ off = 0;
+ ET_LOCK();
+ SLIST_FOREACH(et, &eventtimers, et_all) {
+ off += snprintf(buf + off, sizeof(buf) - off, "%s%s(%d)",
+ spc, et->et_name, et->et_quality);
+ spc = " ";
+ }
+ ET_UNLOCK();
+ error = SYSCTL_OUT(req, buf, strlen(buf));
+ return (error);
+}
+SYSCTL_PROC(_kern_eventtimer, OID_AUTO, choice,
+ CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
+ 0, 0, sysctl_kern_eventtimer_choice, "A", "Present event timers");
+
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