/*
* When cpufreq levels change, find out about the (new) max frequency. We
* use this to update CPU accounting in case it got a lower estimate at boot.
*/
static void
tsc_levels_changed(void *arg, int unit)
{
device_t cf_dev;
struct cf_level *levels;
int count, error;
uint64_t max_freq;
/* Only use values from the first CPU, assuming all are equal. */
if (unit != 0)
return;
/* Find the appropriate cpufreq device instance. */
cf_dev = devclass_get_device(devclass_find("cpufreq"), unit);
if (cf_dev == NULL) {
printf("tsc_levels_changed() called but no cpufreq device?\n");
return;
}
/* Get settings from the device and find the max frequency. */
count = 64;
levels = malloc(count * sizeof(*levels), M_TEMP, M_NOWAIT);
if (levels == NULL)
return;
error = CPUFREQ_LEVELS(cf_dev, levels, &count);
if (error == 0 && count != 0) {
max_freq = (uint64_t)levels[0].total_set.freq * 1000000;
set_cputicker(rdtsc, max_freq, 1);
} else
printf("tsc_levels_changed: no max freq found\n");
free(levels, M_TEMP);
}
static int
acpi_tz_cpufreq_update(struct acpi_tz_softc *sc, int req)
{
device_t dev;
struct cf_level *levels;
int num_levels, error, freq, desired_freq, perf, i;
levels = malloc(CPUFREQ_MAX_LEVELS * sizeof(*levels), M_TEMP, M_NOWAIT);
if (levels == NULL)
return (ENOMEM);
/*
* Find the main device, cpufreq0. We don't yet support independent
* CPU frequency control on SMP.
*/
if ((dev = devclass_get_device(devclass_find("cpufreq"), 0)) == NULL) {
error = ENXIO;
goto out;
}
/* Get the current frequency. */
error = CPUFREQ_GET(dev, &levels[0]);
if (error)
goto out;
freq = levels[0].total_set.freq;
/* Get the current available frequency levels. */
num_levels = CPUFREQ_MAX_LEVELS;
error = CPUFREQ_LEVELS(dev, levels, &num_levels);
if (error) {
if (error == E2BIG)
printf("cpufreq: need to increase CPUFREQ_MAX_LEVELS\n");
goto out;
}
/* Calculate the desired frequency as a percent of the max frequency. */
perf = 100 * freq / levels[0].total_set.freq - req;
if (perf < 0)
perf = 0;
else if (perf > 100)
perf = 100;
desired_freq = levels[0].total_set.freq * perf / 100;
if (desired_freq < freq) {
/* Find the closest available frequency, rounding down. */
for (i = 0; i < num_levels; i++)
if (levels[i].total_set.freq <= desired_freq)
break;
/* If we didn't find a relevant setting, use the lowest. */
if (i == num_levels)
i--;
} else {
/* If we didn't decrease frequency yet, don't increase it. */
if (!sc->tz_cooling_updated) {
sc->tz_cooling_active = FALSE;
goto out;
}
/* Use saved cpu frequency as maximum value. */
if (desired_freq > sc->tz_cooling_saved_freq)
desired_freq = sc->tz_cooling_saved_freq;
/* Find the closest available frequency, rounding up. */
for (i = num_levels - 1; i >= 0; i--)
if (levels[i].total_set.freq >= desired_freq)
break;
/* If we didn't find a relevant setting, use the highest. */
if (i == -1)
i++;
/* If we're going to the highest frequency, restore the old setting. */
if (i == 0 || desired_freq == sc->tz_cooling_saved_freq) {
error = acpi_tz_cpufreq_restore(sc);
if (error == 0)
sc->tz_cooling_active = FALSE;
goto out;
}
}
/* If we are going to a new frequency, activate it. */
if (levels[i].total_set.freq != freq) {
ACPI_VPRINT(sc->tz_dev, acpi_device_get_parent_softc(sc->tz_dev),
"temperature %d.%dC: %screasing clock speed "
"from %d MHz to %d MHz\n",
TZ_KELVTOC(sc->tz_temperature),
(freq > levels[i].total_set.freq) ? "de" : "in",
freq, levels[i].total_set.freq);
error = CPUFREQ_SET(dev, &levels[i], CPUFREQ_PRIO_KERN);
if (error == 0 && !sc->tz_cooling_updated) {
sc->tz_cooling_saved_freq = freq;
sc->tz_cooling_updated = TRUE;
}
}
out:
if (levels)
free(levels, M_TEMP);
return (error);
}