summaryrefslogtreecommitdiffstats
path: root/drivers/devfreq
diff options
context:
space:
mode:
authorDmitry Osipenko <digetx@gmail.com>2019-11-05 00:56:13 +0300
committerChanwoo Choi <cw00.choi@samsung.com>2019-11-06 12:04:01 +0900
commit28615e37be96877e5bb3559f566e50a291cf7a05 (patch)
tree07e54f794cc475578db0f7663da7bc1b37e13ada /drivers/devfreq
parent88ec816446fab2012c73c7096fb8b1924fe6837c (diff)
downloadlinux-28615e37be96877e5bb3559f566e50a291cf7a05.tar.bz2
PM / devfreq: tegra30: Use kHz units for dependency threshold
The dependency threshold designates a memory activity level below which CPU's frequency isn't accounted. Currently the threshold is given in "memory cycle" units and that value depends on the polling interval which is fixed to 12ms in the driver. Later on we'd want to add support for a variable polling interval and thus the threshold value either needs to be scaled in accordance to the polling interval or it needs to be represented in a units that do not depend on the polling interval. It is nicer to have threshold value being defined independently of the polling interval, thus this patch converts the dependency threshold units from "cycle" to "kHz". Having this change as a separate-preparatory patch will make easier to follow further patches. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Diffstat (limited to 'drivers/devfreq')
-rw-r--r--drivers/devfreq/tegra30-devfreq.c30
1 files changed, 17 insertions, 13 deletions
diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
index 852bde6249c7..3bd920829bfd 100644
--- a/drivers/devfreq/tegra30-devfreq.c
+++ b/drivers/devfreq/tegra30-devfreq.c
@@ -96,9 +96,10 @@ struct tegra_devfreq_device_config {
unsigned int boost_down_threshold;
/*
- * Threshold of activity (cycles) below which the CPU frequency isn't
- * to be taken into account. This is to avoid increasing the EMC
- * frequency when the CPU is very busy but not accessing the bus often.
+ * Threshold of activity (cycles translated to kHz) below which the
+ * CPU frequency isn't to be taken into account. This is to avoid
+ * increasing the EMC frequency when the CPU is very busy but not
+ * accessing the bus often.
*/
u32 avg_dependency_threshold;
};
@@ -126,7 +127,7 @@ static const struct tegra_devfreq_device_config actmon_device_configs[] = {
.boost_down_coeff = 90,
.boost_up_threshold = 27,
.boost_down_threshold = 10,
- .avg_dependency_threshold = 50000,
+ .avg_dependency_threshold = 16000, /* 16MHz in kHz units */
},
};
@@ -311,7 +312,6 @@ static unsigned long actmon_device_target_freq(struct tegra_devfreq *tegra,
target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD;
avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold;
target_freq = do_percent(target_freq, avg_sustain_coef);
- target_freq += dev->boost_freq;
return target_freq;
}
@@ -322,15 +322,18 @@ static void actmon_update_target(struct tegra_devfreq *tegra,
unsigned long cpu_freq = 0;
unsigned long static_cpu_emc_freq = 0;
- if (dev->config->avg_dependency_threshold) {
+ dev->target_freq = actmon_device_target_freq(tegra, dev);
+
+ if (dev->config->avg_dependency_threshold &&
+ dev->config->avg_dependency_threshold <= dev->target_freq) {
cpu_freq = cpufreq_quick_get(0);
static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
- }
- dev->target_freq = actmon_device_target_freq(tegra, dev);
-
- if (dev->avg_count >= dev->config->avg_dependency_threshold)
+ dev->target_freq += dev->boost_freq;
dev->target_freq = max(dev->target_freq, static_cpu_emc_freq);
+ } else {
+ dev->target_freq += dev->boost_freq;
+ }
}
static irqreturn_t actmon_thread_isr(int irq, void *data)
@@ -396,15 +399,16 @@ static unsigned long
tegra_actmon_cpufreq_contribution(struct tegra_devfreq *tegra,
unsigned int cpu_freq)
{
+ struct tegra_devfreq_device *actmon_dev = &tegra->devices[MCCPU];
unsigned long static_cpu_emc_freq, dev_freq;
+ dev_freq = actmon_device_target_freq(tegra, actmon_dev);
+
/* check whether CPU's freq is taken into account at all */
- if (tegra->devices[MCCPU].avg_count <
- tegra->devices[MCCPU].config->avg_dependency_threshold)
+ if (dev_freq < actmon_dev->config->avg_dependency_threshold)
return 0;
static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
- dev_freq = actmon_device_target_freq(tegra, &tegra->devices[MCCPU]);
if (dev_freq >= static_cpu_emc_freq)
return 0;