PM / devfreq: tegra30: Tune up MCCPU boost-down coefficient

MCCPU boosts up very aggressively by 800% and boosts down very mildly by
10%. This doesn't work well when system is idling because the very slow
de-boosting results in lots of consecutive-down interrupts, in result
memory stays clocked high and CPU doesn't enter deepest idling state
instead of keeping memory at lowest freq and having CPU cluster turned
off. A more faster de-boosting fixes the case of idling system and doesn't
affect the case of an active system.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
index e44f1a4..0b65f89 100644 (file)
--- a/drivers/devfreq/tegra30-devfreq.c
+++ b/drivers/devfreq/tegra30-devfreq.c
@@ -124,7 +124,7 @@ static const struct tegra_devfreq_device_config actmon_device_configs[] = {
                .offset = 0x200,
                .irq_mask = 1 << 25,
                .boost_up_coeff = 800,
-               .boost_down_coeff = 90,
+               .boost_down_coeff = 40,
                .boost_up_threshold = 27,
                .boost_down_threshold = 10,
                .avg_dependency_threshold = 16000, /* 16MHz in kHz units */