freebsd-dev/sys/kern/kern_cpu.c
Nate Lawson 71ab130c9b Add a check for cpufreq_unregister() being called with no cpufreq device
active.  Note that the logic indicates this should not be possible so
generate a warning if this ever happens.

Found by:	Coverity Prevent (via sam)
2005-03-31 18:56:54 +00:00

921 lines
24 KiB
C

/*-
* Copyright (c) 2004-2005 Nate Lawson (SDG)
* 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.
* 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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/bus.h>
#include <sys/cpu.h>
#include <sys/eventhandler.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sched.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/sbuf.h>
#include <sys/sx.h>
#include <sys/timetc.h>
#include "cpufreq_if.h"
/*
* Common CPU frequency glue code. Drivers for specific hardware can
* attach this interface to allow users to get/set the CPU frequency.
*/
/*
* Number of levels we can handle. Levels are synthesized from settings
* so for M settings and N drivers, there may be M*N levels.
*/
#define CF_MAX_LEVELS 64
struct cpufreq_softc {
struct sx lock;
struct cf_level curr_level;
int curr_priority;
struct cf_level saved_level;
int saved_priority;
struct cf_level_lst all_levels;
int all_count;
int max_mhz;
device_t dev;
struct sysctl_ctx_list sysctl_ctx;
};
struct cf_setting_array {
struct cf_setting sets[MAX_SETTINGS];
int count;
TAILQ_ENTRY(cf_setting_array) link;
};
TAILQ_HEAD(cf_setting_lst, cf_setting_array);
#define CF_MTX_INIT(x) sx_init((x), "cpufreq lock")
#define CF_MTX_LOCK(x) sx_xlock((x))
#define CF_MTX_UNLOCK(x) sx_xunlock((x))
#define CF_MTX_ASSERT(x) sx_assert((x), SX_XLOCKED)
static int cpufreq_attach(device_t dev);
static int cpufreq_detach(device_t dev);
static void cpufreq_evaluate(void *arg);
static int cf_set_method(device_t dev, const struct cf_level *level,
int priority);
static int cf_get_method(device_t dev, struct cf_level *level);
static int cf_levels_method(device_t dev, struct cf_level *levels,
int *count);
static int cpufreq_insert_abs(struct cpufreq_softc *sc,
struct cf_setting *sets, int count);
static int cpufreq_expand_set(struct cpufreq_softc *sc,
struct cf_setting_array *set_arr);
static struct cf_level *cpufreq_dup_set(struct cpufreq_softc *sc,
struct cf_level *dup, struct cf_setting *set);
static int cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS);
static int cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS);
static int cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS);
static device_method_t cpufreq_methods[] = {
DEVMETHOD(device_probe, bus_generic_probe),
DEVMETHOD(device_attach, cpufreq_attach),
DEVMETHOD(device_detach, cpufreq_detach),
DEVMETHOD(cpufreq_set, cf_set_method),
DEVMETHOD(cpufreq_get, cf_get_method),
DEVMETHOD(cpufreq_levels, cf_levels_method),
{0, 0}
};
static driver_t cpufreq_driver = {
"cpufreq", cpufreq_methods, sizeof(struct cpufreq_softc)
};
static devclass_t cpufreq_dc;
DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, cpufreq_dc, 0, 0);
static eventhandler_tag cf_ev_tag;
static int cf_lowest_freq;
TUNABLE_INT("debug.cpufreq.lowest", &cf_lowest_freq);
SYSCTL_NODE(_debug, OID_AUTO, cpufreq, CTLFLAG_RD, NULL, "cpufreq debugging");
SYSCTL_INT(_debug_cpufreq, OID_AUTO, lowest, CTLFLAG_RW, &cf_lowest_freq, 1,
"Don't provide levels below this frequency.");
static int
cpufreq_attach(device_t dev)
{
struct cpufreq_softc *sc;
device_t parent;
int numdevs;
sc = device_get_softc(dev);
parent = device_get_parent(dev);
sc->dev = dev;
sysctl_ctx_init(&sc->sysctl_ctx);
TAILQ_INIT(&sc->all_levels);
CF_MTX_INIT(&sc->lock);
sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
sc->saved_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
/*
* Only initialize one set of sysctls for all CPUs. In the future,
* if multiple CPUs can have different settings, we can move these
* sysctls to be under every CPU instead of just the first one.
*/
numdevs = devclass_get_count(cpufreq_dc);
if (numdevs > 1)
return (0);
SYSCTL_ADD_PROC(&sc->sysctl_ctx,
SYSCTL_CHILDREN(device_get_sysctl_tree(parent)),
OID_AUTO, "freq", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
cpufreq_curr_sysctl, "I", "Current CPU frequency");
SYSCTL_ADD_PROC(&sc->sysctl_ctx,
SYSCTL_CHILDREN(device_get_sysctl_tree(parent)),
OID_AUTO, "freq_levels", CTLTYPE_STRING | CTLFLAG_RD, sc, 0,
cpufreq_levels_sysctl, "A", "CPU frequency levels");
cf_ev_tag = EVENTHANDLER_REGISTER(cpufreq_changed, cpufreq_evaluate,
NULL, EVENTHANDLER_PRI_ANY);
return (0);
}
static int
cpufreq_detach(device_t dev)
{
struct cpufreq_softc *sc;
int numdevs;
sc = device_get_softc(dev);
sysctl_ctx_free(&sc->sysctl_ctx);
/* Only clean up these resources when the last device is detaching. */
numdevs = devclass_get_count(cpufreq_dc);
if (numdevs == 1)
EVENTHANDLER_DEREGISTER(cpufreq_changed, cf_ev_tag);
return (0);
}
static void
cpufreq_evaluate(void *arg)
{
/* TODO: Re-evaluate when notified of changes to drivers. */
}
static int
cf_set_method(device_t dev, const struct cf_level *level, int priority)
{
struct cpufreq_softc *sc;
const struct cf_setting *set;
struct pcpu *pc;
int cpu_id, error, i;
sc = device_get_softc(dev);
error = 0;
set = NULL;
/*
* Check that the TSC isn't being used as a timecounter.
* If it is, then return EBUSY and refuse to change the
* clock speed.
*/
if (strcmp(timecounter->tc_name, "TSC") == 0)
return (EBUSY);
/*
* If the caller didn't specify a level and one is saved, prepare to
* restore the saved level. If none has been saved, return an error.
* If they did specify one, but the requested level has a lower
* priority, don't allow the new level right now.
*/
CF_MTX_LOCK(&sc->lock);
if (level == NULL) {
if (sc->saved_level.total_set.freq != CPUFREQ_VAL_UNKNOWN) {
level = &sc->saved_level;
priority = sc->saved_priority;
} else {
error = ENXIO;
goto out;
}
} else if (priority < sc->curr_priority) {
error = EPERM;
goto out;
}
/* Reject levels that are below our specified threshold. */
if (level->total_set.freq <= cf_lowest_freq) {
error = EINVAL;
goto out;
}
/* If already at this level, just return. */
if (CPUFREQ_CMP(sc->curr_level.total_set.freq, level->total_set.freq))
goto out;
/* First, set the absolute frequency via its driver. */
set = &level->abs_set;
if (set->dev) {
if (!device_is_attached(set->dev)) {
error = ENXIO;
goto out;
}
/* Bind to the target CPU before switching, if necessary. */
cpu_id = PCPU_GET(cpuid);
pc = cpu_get_pcpu(set->dev);
if (cpu_id != pc->pc_cpuid) {
mtx_lock_spin(&sched_lock);
sched_bind(curthread, pc->pc_cpuid);
mtx_unlock_spin(&sched_lock);
}
error = CPUFREQ_DRV_SET(set->dev, set);
if (cpu_id != pc->pc_cpuid) {
mtx_lock_spin(&sched_lock);
sched_unbind(curthread);
mtx_unlock_spin(&sched_lock);
}
if (error) {
goto out;
}
}
/* Next, set any/all relative frequencies via their drivers. */
for (i = 0; i < level->rel_count; i++) {
set = &level->rel_set[i];
if (!device_is_attached(set->dev)) {
error = ENXIO;
goto out;
}
/* Bind to the target CPU before switching, if necessary. */
cpu_id = PCPU_GET(cpuid);
pc = cpu_get_pcpu(set->dev);
if (cpu_id != pc->pc_cpuid) {
mtx_lock_spin(&sched_lock);
sched_bind(curthread, pc->pc_cpuid);
mtx_unlock_spin(&sched_lock);
}
error = CPUFREQ_DRV_SET(set->dev, set);
if (cpu_id != pc->pc_cpuid) {
mtx_lock_spin(&sched_lock);
sched_unbind(curthread);
mtx_unlock_spin(&sched_lock);
}
if (error) {
/* XXX Back out any successful setting? */
goto out;
}
}
/* If we were restoring a saved state, reset it to "unused". */
if (level == &sc->saved_level) {
sc->saved_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
sc->saved_priority = 0;
}
/*
* Before recording the current level, check if we're going to a
* higher priority and have not saved a level yet. If so, save the
* previous level and priority.
*/
if (sc->curr_level.total_set.freq != CPUFREQ_VAL_UNKNOWN &&
sc->saved_level.total_set.freq == CPUFREQ_VAL_UNKNOWN &&
priority > sc->curr_priority) {
sc->saved_level = sc->curr_level;
sc->saved_priority = sc->curr_priority;
}
sc->curr_level = *level;
sc->curr_priority = priority;
error = 0;
out:
CF_MTX_UNLOCK(&sc->lock);
if (error && set)
device_printf(set->dev, "set freq failed, err %d\n", error);
return (error);
}
static int
cf_get_method(device_t dev, struct cf_level *level)
{
struct cpufreq_softc *sc;
struct cf_level *levels;
struct cf_setting *curr_set, set;
struct pcpu *pc;
device_t *devs;
int count, error, i, numdevs;
uint64_t rate;
sc = device_get_softc(dev);
error = 0;
levels = NULL;
/* If we already know the current frequency, we're done. */
CF_MTX_LOCK(&sc->lock);
curr_set = &sc->curr_level.total_set;
if (curr_set->freq != CPUFREQ_VAL_UNKNOWN)
goto out;
CF_MTX_UNLOCK(&sc->lock);
/*
* We need to figure out the current level. Loop through every
* driver, getting the current setting. Then, attempt to get a best
* match of settings against each level.
*/
count = CF_MAX_LEVELS;
levels = malloc(count * sizeof(*levels), M_TEMP, M_NOWAIT);
if (levels == NULL)
return (ENOMEM);
error = CPUFREQ_LEVELS(sc->dev, levels, &count);
if (error) {
if (error == E2BIG)
printf("cpufreq: need to increase CF_MAX_LEVELS\n");
free(levels, M_TEMP);
return (error);
}
error = device_get_children(device_get_parent(dev), &devs, &numdevs);
if (error) {
free(levels, M_TEMP);
return (error);
}
/*
* Reacquire the lock and search for the given level.
*
* XXX Note: this is not quite right since we really need to go
* through each level and compare both absolute and relative
* settings for each driver in the system before making a match.
* The estimation code below catches this case though.
*/
CF_MTX_LOCK(&sc->lock);
for (i = 0; i < numdevs && curr_set->freq == CPUFREQ_VAL_UNKNOWN; i++) {
if (!device_is_attached(devs[i]))
continue;
error = CPUFREQ_DRV_GET(devs[i], &set);
if (error)
continue;
for (i = 0; i < count; i++) {
if (CPUFREQ_CMP(set.freq, levels[i].total_set.freq)) {
sc->curr_level = levels[i];
break;
}
}
}
free(devs, M_TEMP);
if (curr_set->freq != CPUFREQ_VAL_UNKNOWN)
goto out;
/*
* We couldn't find an exact match, so attempt to estimate and then
* match against a level.
*/
pc = cpu_get_pcpu(dev);
if (pc == NULL) {
error = ENXIO;
goto out;
}
cpu_est_clockrate(pc->pc_cpuid, &rate);
rate /= 1000000;
for (i = 0; i < count; i++) {
if (CPUFREQ_CMP(rate, levels[i].total_set.freq)) {
sc->curr_level = levels[i];
break;
}
}
out:
if (error == 0)
*level = sc->curr_level;
CF_MTX_UNLOCK(&sc->lock);
if (levels)
free(levels, M_TEMP);
return (error);
}
static int
cf_levels_method(device_t dev, struct cf_level *levels, int *count)
{
struct cf_setting_array *set_arr;
struct cf_setting_lst rel_sets;
struct cpufreq_softc *sc;
struct cf_level *lev;
struct cf_setting *sets;
struct pcpu *pc;
device_t *devs;
int error, i, numdevs, set_count, type;
uint64_t rate;
if (levels == NULL || count == NULL)
return (EINVAL);
TAILQ_INIT(&rel_sets);
sc = device_get_softc(dev);
error = device_get_children(device_get_parent(dev), &devs, &numdevs);
if (error)
return (error);
sets = malloc(MAX_SETTINGS * sizeof(*sets), M_TEMP, M_NOWAIT);
if (sets == NULL) {
free(devs, M_TEMP);
return (ENOMEM);
}
/* Get settings from all cpufreq drivers. */
CF_MTX_LOCK(&sc->lock);
for (i = 0; i < numdevs; i++) {
/* Skip devices that aren't ready. */
if (!device_is_attached(devs[i]))
continue;
/*
* Get settings, skipping drivers that offer no settings or
* provide settings for informational purposes only.
*/
error = CPUFREQ_DRV_TYPE(devs[i], &type);
if (error || (type & CPUFREQ_FLAG_INFO_ONLY))
continue;
set_count = MAX_SETTINGS;
error = CPUFREQ_DRV_SETTINGS(devs[i], sets, &set_count);
if (error || set_count == 0)
continue;
/* Add the settings to our absolute/relative lists. */
switch (type & CPUFREQ_TYPE_MASK) {
case CPUFREQ_TYPE_ABSOLUTE:
error = cpufreq_insert_abs(sc, sets, set_count);
break;
case CPUFREQ_TYPE_RELATIVE:
set_arr = malloc(sizeof(*set_arr), M_TEMP, M_NOWAIT);
if (set_arr == NULL) {
error = ENOMEM;
goto out;
}
bcopy(sets, set_arr->sets, set_count * sizeof(*sets));
set_arr->count = set_count;
TAILQ_INSERT_TAIL(&rel_sets, set_arr, link);
break;
default:
error = EINVAL;
break;
}
if (error)
goto out;
}
/*
* If there are no absolute levels, create a fake one at 100%. We
* then cache the clockrate for later use as our base frequency.
*
* XXX This assumes that the first time through, if we only have
* relative drivers, the CPU is currently running at 100%.
*/
if (TAILQ_EMPTY(&sc->all_levels)) {
if (sc->max_mhz == CPUFREQ_VAL_UNKNOWN) {
pc = cpu_get_pcpu(dev);
cpu_est_clockrate(pc->pc_cpuid, &rate);
sc->max_mhz = rate / 1000000;
}
memset(&sets[0], CPUFREQ_VAL_UNKNOWN, sizeof(*sets));
sets[0].freq = sc->max_mhz;
sets[0].dev = NULL;
error = cpufreq_insert_abs(sc, sets, 1);
if (error)
goto out;
}
/* Create a combined list of absolute + relative levels. */
TAILQ_FOREACH(set_arr, &rel_sets, link)
cpufreq_expand_set(sc, set_arr);
/* If the caller doesn't have enough space, return the actual count. */
if (sc->all_count > *count) {
*count = sc->all_count;
error = E2BIG;
goto out;
}
/* Finally, output the list of levels. */
i = 0;
TAILQ_FOREACH(lev, &sc->all_levels, link) {
/* Skip levels that have a frequency that is too low. */
if (lev->total_set.freq <= cf_lowest_freq) {
sc->all_count--;
continue;
}
levels[i] = *lev;
i++;
}
*count = sc->all_count;
error = 0;
out:
/* Clear all levels since we regenerate them each time. */
while ((lev = TAILQ_FIRST(&sc->all_levels)) != NULL) {
TAILQ_REMOVE(&sc->all_levels, lev, link);
free(lev, M_TEMP);
}
sc->all_count = 0;
CF_MTX_UNLOCK(&sc->lock);
while ((set_arr = TAILQ_FIRST(&rel_sets)) != NULL) {
TAILQ_REMOVE(&rel_sets, set_arr, link);
free(set_arr, M_TEMP);
}
free(devs, M_TEMP);
free(sets, M_TEMP);
return (error);
}
/*
* Create levels for an array of absolute settings and insert them in
* sorted order in the specified list.
*/
static int
cpufreq_insert_abs(struct cpufreq_softc *sc, struct cf_setting *sets,
int count)
{
struct cf_level_lst *list;
struct cf_level *level, *search;
int i;
CF_MTX_ASSERT(&sc->lock);
list = &sc->all_levels;
for (i = 0; i < count; i++) {
level = malloc(sizeof(*level), M_TEMP, M_NOWAIT | M_ZERO);
if (level == NULL)
return (ENOMEM);
level->abs_set = sets[i];
level->total_set = sets[i];
level->total_set.dev = NULL;
sc->all_count++;
if (TAILQ_EMPTY(list)) {
TAILQ_INSERT_HEAD(list, level, link);
continue;
}
TAILQ_FOREACH_REVERSE(search, list, cf_level_lst, link) {
if (sets[i].freq <= search->total_set.freq) {
TAILQ_INSERT_AFTER(list, search, level, link);
break;
}
}
}
return (0);
}
/*
* Expand a group of relative settings, creating derived levels from them.
*/
static int
cpufreq_expand_set(struct cpufreq_softc *sc, struct cf_setting_array *set_arr)
{
struct cf_level *fill, *search;
struct cf_setting *set;
int i;
CF_MTX_ASSERT(&sc->lock);
TAILQ_FOREACH(search, &sc->all_levels, link) {
/* Skip this level if we've already modified it. */
for (i = 0; i < search->rel_count; i++) {
if (search->rel_set[i].dev == set_arr->sets[0].dev)
break;
}
if (i != search->rel_count)
continue;
/* Add each setting to the level, duplicating if necessary. */
for (i = 0; i < set_arr->count; i++) {
set = &set_arr->sets[i];
/*
* If this setting is less than 100%, split the level
* into two and add this setting to the new level.
*/
fill = search;
if (set->freq < 10000)
fill = cpufreq_dup_set(sc, search, set);
/*
* The new level was a duplicate of an existing level
* so we freed it. Go to the next setting.
*/
if (fill == NULL)
continue;
/* Add this setting to the existing or new level. */
KASSERT(fill->rel_count < MAX_SETTINGS,
("cpufreq: too many relative drivers (%d)",
MAX_SETTINGS));
fill->rel_set[fill->rel_count] = *set;
fill->rel_count++;
}
}
return (0);
}
static struct cf_level *
cpufreq_dup_set(struct cpufreq_softc *sc, struct cf_level *dup,
struct cf_setting *set)
{
struct cf_level_lst *list;
struct cf_level *fill, *itr;
struct cf_setting *fill_set, *itr_set;
int i;
CF_MTX_ASSERT(&sc->lock);
/*
* Create a new level, copy it from the old one, and update the
* total frequency and power by the percentage specified in the
* relative setting.
*/
fill = malloc(sizeof(*fill), M_TEMP, M_NOWAIT);
if (fill == NULL)
return (NULL);
*fill = *dup;
fill_set = &fill->total_set;
fill_set->freq =
((uint64_t)fill_set->freq * set->freq) / 10000;
if (fill_set->power != CPUFREQ_VAL_UNKNOWN) {
fill_set->power = ((uint64_t)fill_set->power * set->freq)
/ 10000;
}
if (set->lat != CPUFREQ_VAL_UNKNOWN) {
if (fill_set->lat != CPUFREQ_VAL_UNKNOWN)
fill_set->lat += set->lat;
else
fill_set->lat = set->lat;
}
/*
* If we copied an old level that we already modified (say, at 100%),
* we need to remove that setting before adding this one. Since we
* process each setting array in order, we know any settings for this
* driver will be found at the end.
*/
for (i = fill->rel_count; i != 0; i--) {
if (fill->rel_set[i - 1].dev != set->dev)
break;
fill->rel_count--;
}
/*
* Insert the new level in sorted order. If we find a duplicate,
* free the new level. We can do this since any existing level will
* be guaranteed to have the same or less settings and thus consume
* less power. For example, a level with one absolute setting of
* 800 Mhz uses less power than one composed of an absolute setting
* of 1600 Mhz and a relative setting at 50%.
*/
list = &sc->all_levels;
if (TAILQ_EMPTY(list)) {
TAILQ_INSERT_HEAD(list, fill, link);
} else {
TAILQ_FOREACH_REVERSE(itr, list, cf_level_lst, link) {
itr_set = &itr->total_set;
if (CPUFREQ_CMP(fill_set->freq, itr_set->freq)) {
free(fill, M_TEMP);
fill = NULL;
break;
} else if (fill_set->freq < itr_set->freq) {
TAILQ_INSERT_AFTER(list, itr, fill, link);
sc->all_count++;
break;
}
}
}
return (fill);
}
static int
cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS)
{
struct cpufreq_softc *sc;
struct cf_level *levels;
int count, devcount, error, freq, i, n;
device_t *devs;
devs = NULL;
sc = oidp->oid_arg1;
levels = malloc(CF_MAX_LEVELS * sizeof(*levels), M_TEMP, M_NOWAIT);
if (levels == NULL)
return (ENOMEM);
error = CPUFREQ_GET(sc->dev, &levels[0]);
if (error)
goto out;
freq = levels[0].total_set.freq;
error = sysctl_handle_int(oidp, &freq, 0, req);
if (error != 0 || req->newptr == NULL)
goto out;
/*
* While we only call cpufreq_get() on one device (assuming all
* CPUs have equal levels), we call cpufreq_set() on all CPUs.
* This is needed for some MP systems.
*/
error = devclass_get_devices(cpufreq_dc, &devs, &devcount);
if (error)
goto out;
for (n = 0; n < devcount; n++) {
count = CF_MAX_LEVELS;
error = CPUFREQ_LEVELS(devs[n], levels, &count);
if (error) {
if (error == E2BIG)
printf(
"cpufreq: need to increase CF_MAX_LEVELS\n");
break;
}
for (i = 0; i < count; i++) {
if (CPUFREQ_CMP(levels[i].total_set.freq, freq)) {
error = CPUFREQ_SET(devs[n], &levels[i],
CPUFREQ_PRIO_USER);
break;
}
}
if (i == count) {
error = EINVAL;
break;
}
}
out:
if (devs)
free(devs, M_TEMP);
if (levels)
free(levels, M_TEMP);
return (error);
}
static int
cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS)
{
struct cpufreq_softc *sc;
struct cf_level *levels;
struct cf_setting *set;
struct sbuf sb;
int count, error, i;
sc = oidp->oid_arg1;
sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND);
/* Get settings from the device and generate the output string. */
count = CF_MAX_LEVELS;
levels = malloc(count * sizeof(*levels), M_TEMP, M_NOWAIT);
if (levels == NULL)
return (ENOMEM);
error = CPUFREQ_LEVELS(sc->dev, levels, &count);
if (error) {
if (error == E2BIG)
printf("cpufreq: need to increase CF_MAX_LEVELS\n");
goto out;
}
if (count) {
for (i = 0; i < count; i++) {
set = &levels[i].total_set;
sbuf_printf(&sb, "%d/%d ", set->freq, set->power);
}
} else
sbuf_cpy(&sb, "0");
sbuf_trim(&sb);
sbuf_finish(&sb);
error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
out:
free(levels, M_TEMP);
sbuf_delete(&sb);
return (error);
}
static int
cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS)
{
device_t dev;
struct cf_setting *sets;
struct sbuf sb;
int error, i, set_count;
dev = oidp->oid_arg1;
sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND);
/* Get settings from the device and generate the output string. */
set_count = MAX_SETTINGS;
sets = malloc(set_count * sizeof(*sets), M_TEMP, M_NOWAIT);
if (sets == NULL)
return (ENOMEM);
error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count);
if (error)
goto out;
if (set_count) {
for (i = 0; i < set_count; i++)
sbuf_printf(&sb, "%d/%d ", sets[i].freq, sets[i].power);
} else
sbuf_cpy(&sb, "0");
sbuf_trim(&sb);
sbuf_finish(&sb);
error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
out:
free(sets, M_TEMP);
sbuf_delete(&sb);
return (error);
}
int
cpufreq_register(device_t dev)
{
struct cpufreq_softc *sc;
device_t cf_dev, cpu_dev;
/* Add a sysctl to get each driver's settings separately. */
SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
OID_AUTO, "freq_settings", CTLTYPE_STRING | CTLFLAG_RD, dev, 0,
cpufreq_settings_sysctl, "A", "CPU frequency driver settings");
/*
* Add only one cpufreq device to each CPU. Currently, all CPUs
* must offer the same levels and be switched at the same time.
*/
cpu_dev = device_get_parent(dev);
if ((cf_dev = device_find_child(cpu_dev, "cpufreq", -1))) {
sc = device_get_softc(cf_dev);
sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
return (0);
}
/* Add the child device and possibly sysctls. */
cf_dev = BUS_ADD_CHILD(cpu_dev, 0, "cpufreq", -1);
if (cf_dev == NULL)
return (ENOMEM);
device_quiet(cf_dev);
return (device_probe_and_attach(cf_dev));
}
int
cpufreq_unregister(device_t dev)
{
device_t cf_dev, *devs;
int cfcount, devcount, error, i, type;
/*
* If this is the last cpufreq child device, remove the control
* device as well. We identify cpufreq children by calling a method
* they support.
*/
error = device_get_children(device_get_parent(dev), &devs, &devcount);
if (error)
return (error);
cf_dev = device_find_child(device_get_parent(dev), "cpufreq", -1);
if (cf_dev == NULL) {
device_printf(dev,
"warning: cpufreq_unregister called with no cpufreq device active\n");
return (0);
}
cfcount = 0;
for (i = 0; i < devcount; i++) {
if (!device_is_attached(devs[i]))
continue;
if (CPUFREQ_DRV_TYPE(devs[i], &type) == 0)
cfcount++;
}
if (cfcount <= 1)
device_delete_child(device_get_parent(cf_dev), cf_dev);
free(devs, M_TEMP);
return (0);
}