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freebsd-nq/sys/kern/kern_cpu.c

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/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2004-2007 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/sbuf.h>
#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/sx.h>
#include <sys/timetc.h>
#include <sys/taskqueue.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 256
struct cf_saved_freq {
struct cf_level level;
int priority;
SLIST_ENTRY(cf_saved_freq) link;
};
struct cpufreq_softc {
struct sx lock;
struct cf_level curr_level;
int curr_priority;
SLIST_HEAD(, cf_saved_freq) saved_freq;
struct cf_level_lst all_levels;
int all_count;
int max_mhz;
device_t dev;
device_t cf_drv_dev;
struct sysctl_ctx_list sysctl_ctx;
struct task startup_task;
struct cf_level *levels_buf;
};
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)
#define CF_DEBUG(msg...) do { \
if (cf_verbose) \
printf("cpufreq: " msg); \
} while (0)
static int cpufreq_attach(device_t dev);
static void cpufreq_startup_task(void *ctx, int pending);
static int cpufreq_detach(device_t dev);
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)
};
DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, 0, 0);
static int cf_lowest_freq;
static int cf_verbose;
static SYSCTL_NODE(_debug, OID_AUTO, cpufreq, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
"cpufreq debugging");
SYSCTL_INT(_debug_cpufreq, OID_AUTO, lowest, CTLFLAG_RWTUN, &cf_lowest_freq, 1,
"Don't provide levels below this frequency.");
SYSCTL_INT(_debug_cpufreq, OID_AUTO, verbose, CTLFLAG_RWTUN, &cf_verbose, 1,
"Print verbose debugging messages");
/*
* This is called as the result of a hardware specific frequency control driver
* calling cpufreq_register. It provides a general interface for system wide
* frequency controls and operates on a per cpu basis.
*/
static int
cpufreq_attach(device_t dev)
{
struct cpufreq_softc *sc;
struct pcpu *pc;
device_t parent;
uint64_t rate;
CF_DEBUG("initializing %s\n", device_get_nameunit(dev));
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;
SLIST_INIT(&sc->saved_freq);
/* Try to get nominal CPU freq to use it as maximum later if needed */
sc->max_mhz = cpu_get_nominal_mhz(dev);
/* If that fails, try to measure the current rate */
if (sc->max_mhz <= 0) {
CF_DEBUG("Unable to obtain nominal frequency.\n");
pc = cpu_get_pcpu(dev);
if (cpu_est_clockrate(pc->pc_cpuid, &rate) == 0)
sc->max_mhz = rate / 1000000;
else
sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
}
CF_DEBUG("initializing one-time data for %s\n",
device_get_nameunit(dev));
sc->levels_buf = malloc(CF_MAX_LEVELS * sizeof(*sc->levels_buf),
M_DEVBUF, M_WAITOK);
SYSCTL_ADD_PROC(&sc->sysctl_ctx,
SYSCTL_CHILDREN(device_get_sysctl_tree(parent)),
OID_AUTO, "freq", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
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 | CTLFLAG_NEEDGIANT, sc, 0,
cpufreq_levels_sysctl, "A", "CPU frequency levels");
/*
* Queue a one-shot broadcast that levels have changed.
* It will run once the system has completed booting.
*/
TASK_INIT(&sc->startup_task, 0, cpufreq_startup_task, dev);
taskqueue_enqueue(taskqueue_thread, &sc->startup_task);
return (0);
}
/* Handle any work to be done for all drivers that attached during boot. */
static void
cpufreq_startup_task(void *ctx, int pending)
{
cpufreq_settings_changed((device_t)ctx);
}
static int
cpufreq_detach(device_t dev)
{
struct cpufreq_softc *sc;
struct cf_saved_freq *saved_freq;
CF_DEBUG("shutdown %s\n", device_get_nameunit(dev));
sc = device_get_softc(dev);
sysctl_ctx_free(&sc->sysctl_ctx);
while ((saved_freq = SLIST_FIRST(&sc->saved_freq)) != NULL) {
SLIST_REMOVE_HEAD(&sc->saved_freq, link);
free(saved_freq, M_TEMP);
}
free(sc->levels_buf, M_DEVBUF);
return (0);
}
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 cf_saved_freq *saved_freq, *curr_freq;
struct pcpu *pc;
int error, i;
u_char pri;
sc = device_get_softc(dev);
error = 0;
set = NULL;
saved_freq = NULL;
/* We are going to change levels so notify the pre-change handler. */
EVENTHANDLER_INVOKE(cpufreq_pre_change, level, &error);
if (error != 0) {
EVENTHANDLER_INVOKE(cpufreq_post_change, level, error);
return (error);
}
CF_MTX_LOCK(&sc->lock);
#ifdef SMP
#ifdef EARLY_AP_STARTUP
MPASS(mp_ncpus == 1 || smp_started);
#else
/*
* If still booting and secondary CPUs not started yet, don't allow
* changing the frequency until they're online. This is because we
* can't switch to them using sched_bind() and thus we'd only be
* switching the main CPU. XXXTODO: Need to think more about how to
* handle having different CPUs at different frequencies.
*/
if (mp_ncpus > 1 && !smp_started) {
device_printf(dev, "rejecting change, SMP not started yet\n");
error = ENXIO;
goto out;
}
#endif
#endif /* SMP */
/*
* If the requested level has a lower priority, don't allow
* the new level right now.
*/
if (priority < sc->curr_priority) {
CF_DEBUG("ignoring, curr prio %d less than %d\n", priority,
sc->curr_priority);
error = EPERM;
goto out;
}
/*
* 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 (level == NULL) {
saved_freq = SLIST_FIRST(&sc->saved_freq);
if (saved_freq == NULL) {
CF_DEBUG("NULL level, no saved level\n");
error = ENXIO;
goto out;
}
level = &saved_freq->level;
priority = saved_freq->priority;
CF_DEBUG("restoring saved level, freq %d prio %d\n",
level->total_set.freq, priority);
}
/* Reject levels that are below our specified threshold. */
if (level->total_set.freq < cf_lowest_freq) {
CF_DEBUG("rejecting freq %d, less than %d limit\n",
level->total_set.freq, cf_lowest_freq);
error = EINVAL;
goto out;
}
/* If already at this level, just return. */
if (sc->curr_level.total_set.freq == level->total_set.freq) {
CF_DEBUG("skipping freq %d, same as current level %d\n",
level->total_set.freq, sc->curr_level.total_set.freq);
goto skip;
}
/* 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. */
pc = cpu_get_pcpu(set->dev);
/* Skip settings if CPU is not started. */
if (pc == NULL) {
error = 0;
goto out;
}
thread_lock(curthread);
pri = curthread->td_priority;
sched_prio(curthread, PRI_MIN);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
CF_DEBUG("setting abs freq %d on %s (cpu %d)\n", set->freq,
device_get_nameunit(set->dev), PCPU_GET(cpuid));
error = CPUFREQ_DRV_SET(set->dev, set);
thread_lock(curthread);
sched_unbind(curthread);
sched_prio(curthread, pri);
thread_unlock(curthread);
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. */
pc = cpu_get_pcpu(set->dev);
thread_lock(curthread);
pri = curthread->td_priority;
sched_prio(curthread, PRI_MIN);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
CF_DEBUG("setting rel freq %d on %s (cpu %d)\n", set->freq,
device_get_nameunit(set->dev), PCPU_GET(cpuid));
error = CPUFREQ_DRV_SET(set->dev, set);
thread_lock(curthread);
sched_unbind(curthread);
sched_prio(curthread, pri);
thread_unlock(curthread);
if (error) {
/* XXX Back out any successful setting? */
goto out;
}
}
skip:
/*
* Before recording the current level, check if we're going to a
* higher priority. If so, save the previous level and priority.
*/
if (sc->curr_level.total_set.freq != CPUFREQ_VAL_UNKNOWN &&
priority > sc->curr_priority) {
CF_DEBUG("saving level, freq %d prio %d\n",
sc->curr_level.total_set.freq, sc->curr_priority);
curr_freq = malloc(sizeof(*curr_freq), M_TEMP, M_NOWAIT);
if (curr_freq == NULL) {
error = ENOMEM;
goto out;
}
curr_freq->level = sc->curr_level;
curr_freq->priority = sc->curr_priority;
SLIST_INSERT_HEAD(&sc->saved_freq, curr_freq, link);
}
sc->curr_level = *level;
sc->curr_priority = priority;
/* If we were restoring a saved state, reset it to "unused". */
if (saved_freq != NULL) {
CF_DEBUG("resetting saved level\n");
sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
SLIST_REMOVE_HEAD(&sc->saved_freq, link);
free(saved_freq, M_TEMP);
}
out:
CF_MTX_UNLOCK(&sc->lock);
/*
* We changed levels (or attempted to) so notify the post-change
* handler of new frequency or error.
*/
EVENTHANDLER_INVOKE(cpufreq_post_change, level, error);
if (error && set)
device_printf(set->dev, "set freq failed, err %d\n", error);
return (error);
}
static int
cpufreq_get_frequency(device_t dev)
{
struct cf_setting set;
if (CPUFREQ_DRV_GET(dev, &set) != 0)
return (-1);
return (set.freq);
}
/* Returns the index into *levels with the match */
static int
cpufreq_get_level(device_t dev, struct cf_level *levels, int count)
{
int i, freq;
if ((freq = cpufreq_get_frequency(dev)) < 0)
return (-1);
for (i = 0; i < count; i++)
if (freq == levels[i].total_set.freq)
return (i);
return (-1);
}
/*
* Used by the cpufreq core, this function will populate *level with the current
* frequency as either determined by a cached value sc->curr_level, or in the
* case the lower level driver has set the CPUFREQ_FLAG_UNCACHED flag, it will
* obtain the frequency from the driver itself.
*/
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;
struct pcpu *pc;
int bdiff, count, diff, error, i, type;
uint64_t rate;
sc = device_get_softc(dev);
error = 0;
levels = NULL;
/*
* If we already know the current frequency, and the driver didn't ask
* for uncached usage, we're done.
*/
CF_MTX_LOCK(&sc->lock);
curr_set = &sc->curr_level.total_set;
error = CPUFREQ_DRV_TYPE(sc->cf_drv_dev, &type);
if (error == 0 && (type & CPUFREQ_FLAG_UNCACHED)) {
struct cf_setting set;
/*
* If the driver wants to always report back the real frequency,
* first try the driver and if that fails, fall back to
* estimating.
*/
if (CPUFREQ_DRV_GET(sc->cf_drv_dev, &set) == 0) {
sc->curr_level.total_set = set;
CF_DEBUG("get returning immediate freq %d\n",
curr_set->freq);
goto out;
}
} else if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) {
CF_DEBUG("get returning known freq %d\n", curr_set->freq);
error = 0;
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);
}
/*
* 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);
i = cpufreq_get_level(sc->cf_drv_dev, levels, count);
if (i >= 0)
sc->curr_level = levels[i];
else
CF_DEBUG("Couldn't find supported level for %s\n",
device_get_nameunit(sc->cf_drv_dev));
if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) {
CF_DEBUG("get matched freq %d from drivers\n", curr_set->freq);
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;
bdiff = 1 << 30;
for (i = 0; i < count; i++) {
diff = abs(levels[i].total_set.freq - rate);
if (diff < bdiff) {
bdiff = diff;
sc->curr_level = levels[i];
}
}
CF_DEBUG("get estimated freq %d\n", curr_set->freq);
out:
if (error == 0)
*level = sc->curr_level;
CF_MTX_UNLOCK(&sc->lock);
if (levels)
free(levels, M_TEMP);
return (error);
}
/*
* Either directly obtain settings from the cpufreq driver, or build a list of
* relative settings to be integrated later against an absolute max.
*/
static int
cpufreq_add_levels(device_t cf_dev, struct cf_setting_lst *rel_sets)
{
struct cf_setting_array *set_arr;
struct cf_setting *sets;
device_t dev;
struct cpufreq_softc *sc;
int type, set_count, error;
sc = device_get_softc(cf_dev);
dev = sc->cf_drv_dev;
/* Skip devices that aren't ready. */
if (!device_is_attached(cf_dev))
return (0);
/*
* Get settings, skipping drivers that offer no settings or
* provide settings for informational purposes only.
*/
error = CPUFREQ_DRV_TYPE(dev, &type);
if (error != 0 || (type & CPUFREQ_FLAG_INFO_ONLY)) {
if (error == 0) {
CF_DEBUG("skipping info-only driver %s\n",
device_get_nameunit(cf_dev));
}
return (error);
}
sets = malloc(MAX_SETTINGS * sizeof(*sets), M_TEMP, M_NOWAIT);
if (sets == NULL)
return (ENOMEM);
set_count = MAX_SETTINGS;
error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count);
if (error != 0 || set_count == 0)
goto out;
/* 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:
CF_DEBUG("adding %d relative settings\n", set_count);
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;
}
out:
free(sets, 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 pcpu *pc;
int error, i;
uint64_t rate;
if (levels == NULL || count == NULL)
return (EINVAL);
TAILQ_INIT(&rel_sets);
sc = device_get_softc(dev);
CF_MTX_LOCK(&sc->lock);
error = cpufreq_add_levels(sc->dev, &rel_sets);
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.
*/
if (TAILQ_EMPTY(&sc->all_levels)) {
struct cf_setting set;
CF_DEBUG("No absolute levels returned by driver\n");
if (sc->max_mhz == CPUFREQ_VAL_UNKNOWN) {
sc->max_mhz = cpu_get_nominal_mhz(dev);
/*
* If the CPU can't report a rate for 100%, hope
* the CPU is running at its nominal rate right now,
* and use that instead.
*/
if (sc->max_mhz <= 0) {
pc = cpu_get_pcpu(dev);
cpu_est_clockrate(pc->pc_cpuid, &rate);
sc->max_mhz = rate / 1000000;
}
}
memset(&set, CPUFREQ_VAL_UNKNOWN, sizeof(set));
set.freq = sc->max_mhz;
set.dev = NULL;
error = cpufreq_insert_abs(sc, &set, 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);
}
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, inserted;
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++;
inserted = 0;
if (TAILQ_EMPTY(list)) {
CF_DEBUG("adding abs setting %d at head\n",
sets[i].freq);
TAILQ_INSERT_HEAD(list, level, link);
continue;
}
TAILQ_FOREACH_REVERSE(search, list, cf_level_lst, link)
if (sets[i].freq <= search->total_set.freq) {
CF_DEBUG("adding abs setting %d after %d\n",
sets[i].freq, search->total_set.freq);
TAILQ_INSERT_AFTER(list, search, level, link);
inserted = 1;
break;
}
if (inserted == 0) {
TAILQ_FOREACH(search, list, link)
if (sets[i].freq >= search->total_set.freq) {
CF_DEBUG("adding abs setting %d before %d\n",
sets[i].freq, search->total_set.freq);
TAILQ_INSERT_BEFORE(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);
/*
* Walk the set of all existing levels in reverse. This is so we
* create derived states from the lowest absolute settings first
* and discard duplicates created from higher absolute settings.
* For instance, a level of 50 Mhz derived from 100 Mhz + 50% is
* preferable to 200 Mhz + 25% because absolute settings are more
* efficient since they often change the voltage as well.
*/
TAILQ_FOREACH_REVERSE(search, &sc->all_levels, cf_level_lst, link) {
/* 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 or its absolute setting is too high
* so we freed it. For example, we discard a
* derived level of 1000 MHz/25% if a level
* of 500 MHz/100% already exists.
*/
if (fill == NULL)
break;
}
/* 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++;
CF_DEBUG(
"expand set added rel setting %d%% to %d level\n",
set->freq / 100, fill->total_set.freq);
}
}
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;
}
CF_DEBUG("dup set considering derived setting %d\n", fill_set->freq);
/*
* 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;
CF_DEBUG("removed last relative driver: %s\n",
device_get_nameunit(set->dev));
fill->rel_count--;
}
/*
* Insert the new level in sorted order. If it is a duplicate of an
* existing level (1) or has an absolute setting higher than the
* existing level (2), do not add it. We can do this since any such
* level is guaranteed use less power. For example (1), 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%.
* Also for example (2), a level of 800 Mhz/75% is preferable to
* 1600 Mhz/25% even though the latter has a lower total frequency.
*/
list = &sc->all_levels;
KASSERT(!TAILQ_EMPTY(list), ("all levels list empty in dup set"));
TAILQ_FOREACH_REVERSE(itr, list, cf_level_lst, link) {
itr_set = &itr->total_set;
if (CPUFREQ_CMP(fill_set->freq, itr_set->freq)) {
CF_DEBUG("dup set rejecting %d (dupe)\n",
fill_set->freq);
itr = NULL;
break;
} else if (fill_set->freq < itr_set->freq) {
if (fill->abs_set.freq <= itr->abs_set.freq) {
CF_DEBUG(
"dup done, inserting new level %d after %d\n",
fill_set->freq, itr_set->freq);
TAILQ_INSERT_AFTER(list, itr, fill, link);
sc->all_count++;
} else {
CF_DEBUG("dup set rejecting %d (abs too big)\n",
fill_set->freq);
itr = NULL;
}
break;
}
}
/* We didn't find a good place for this new level so free it. */
if (itr == NULL) {
CF_DEBUG("dup set freeing new level %d (not optimal)\n",
fill_set->freq);
free(fill, M_TEMP);
fill = NULL;
}
return (fill);
}
static int
cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS)
{
struct cpufreq_softc *sc;
struct cf_level *levels;
int best, count, diff, bdiff, devcount, error, freq, i, n;
device_t *devs;
devs = NULL;
sc = oidp->oid_arg1;
levels = sc->levels_buf;
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(devclass_find("cpufreq"), &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;
}
best = 0;
bdiff = 1 << 30;
for (i = 0; i < count; i++) {
diff = abs(levels[i].total_set.freq - freq);
if (diff < bdiff) {
bdiff = diff;
best = i;
}
}
error = CPUFREQ_SET(devs[n], &levels[best], CPUFREQ_PRIO_USER);
}
out:
if (devs)
free(devs, 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 = sc->levels_buf;
if (levels == NULL) {
sbuf_delete(&sb);
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:
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) {
sbuf_delete(&sb);
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);
}
static void
cpufreq_add_freq_driver_sysctl(device_t cf_dev)
{
struct cpufreq_softc *sc;
sc = device_get_softc(cf_dev);
SYSCTL_ADD_CONST_STRING(&sc->sysctl_ctx,
SYSCTL_CHILDREN(device_get_sysctl_tree(cf_dev)), OID_AUTO,
"freq_driver", CTLFLAG_RD, device_get_nameunit(sc->cf_drv_dev),
"cpufreq driver used by this cpu");
}
int
cpufreq_register(device_t dev)
{
struct cpufreq_softc *sc;
device_t cf_dev, cpu_dev;
int error;
/* 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 | CTLFLAG_NEEDGIANT, 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;
MPASS(sc->cf_drv_dev != NULL);
return (0);
}
/* Add the child device and possibly sysctls. */
cf_dev = BUS_ADD_CHILD(cpu_dev, 0, "cpufreq", device_get_unit(cpu_dev));
if (cf_dev == NULL)
return (ENOMEM);
device_quiet(cf_dev);
error = device_probe_and_attach(cf_dev);
if (error)
return (error);
sc = device_get_softc(cf_dev);
sc->cf_drv_dev = dev;
cpufreq_add_freq_driver_sysctl(cf_dev);
return (error);
}
int
cpufreq_unregister(device_t dev)
{
device_t cf_dev;
struct cpufreq_softc *sc __diagused;
/*
* If this is the last cpufreq child device, remove the control
* device as well. We identify cpufreq children by calling a method
* they support.
*/
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);
}
sc = device_get_softc(cf_dev);
MPASS(sc->cf_drv_dev == dev);
device_delete_child(device_get_parent(cf_dev), cf_dev);
return (0);
}
int
cpufreq_settings_changed(device_t dev)
{
EVENTHANDLER_INVOKE(cpufreq_levels_changed,
device_get_unit(device_get_parent(dev)));
return (0);
}
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