diff options
Diffstat (limited to 'sys/kern/kern_cpu.c')
| -rw-r--r-- | sys/kern/kern_cpu.c | 1063 |
1 files changed, 1063 insertions, 0 deletions
diff --git a/sys/kern/kern_cpu.c b/sys/kern/kern_cpu.c new file mode 100644 index 0000000..6df4d3f --- /dev/null +++ b/sys/kern/kern_cpu.c @@ -0,0 +1,1063 @@ +/*- + * 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 64 + +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; + 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) +}; +static devclass_t cpufreq_dc; +DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, cpufreq_dc, 0, 0); + +static int cf_lowest_freq; +static int cf_verbose; +TUNABLE_INT("debug.cpufreq.lowest", &cf_lowest_freq); +TUNABLE_INT("debug.cpufreq.verbose", &cf_verbose); +static 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."); +SYSCTL_INT(_debug_cpufreq, OID_AUTO, verbose, CTLFLAG_RW, &cf_verbose, 1, + "Print verbose debugging messages"); + +static int +cpufreq_attach(device_t dev) +{ + struct cpufreq_softc *sc; + struct pcpu *pc; + device_t parent; + uint64_t rate; + int numdevs; + + 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) { + 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; + } + + /* + * 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); + + 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, 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"); + + /* + * 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; + int numdevs; + + 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); + } + + /* Only clean up these resources when the last device is detaching. */ + numdevs = devclass_get_count(cpufreq_dc); + if (numdevs == 1) { + CF_DEBUG("final shutdown for %s\n", device_get_nameunit(dev)); + 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; + + 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 + /* + * 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_active) { + device_printf(dev, "rejecting change, SMP not started yet\n"); + error = ENXIO; + goto out; + } +#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); + thread_lock(curthread); + 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); + 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); + 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); + 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 +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, n, 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) { + CF_DEBUG("get returning known freq %d\n", curr_set->freq); + 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 (n = 0; n < numdevs && curr_set->freq == CPUFREQ_VAL_UNKNOWN; n++) { + if (!device_is_attached(devs[n])) + continue; + if (CPUFREQ_DRV_GET(devs[n], &set) != 0) + continue; + for (i = 0; i < count; i++) { + if (set.freq == levels[i].total_set.freq) { + sc->curr_level = levels[i]; + break; + } + } + } + free(devs, M_TEMP); + 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; + for (i = 0; i < count; i++) { + if (CPUFREQ_CMP(rate, levels[i].total_set.freq)) { + sc->curr_level = levels[i]; + CF_DEBUG("get estimated freq %d\n", curr_set->freq); + goto out; + } + } + error = ENXIO; + +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)) { + if (error == 0) { + CF_DEBUG("skipping info-only driver %s\n", + device_get_nameunit(devs[i])); + } + 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: + 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; + } + 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)) { + 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(&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)) { + 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); + 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(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; + } + 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); +} + +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); +} + +int +cpufreq_settings_changed(device_t dev) +{ + + EVENTHANDLER_INVOKE(cpufreq_levels_changed, + device_get_unit(device_get_parent(dev))); + return (0); +} |
