Documentation/arm/nvidia/tegra_parameters.txt

This file documents NVIDIA Tegra specific sysfs and debugfs files and
kernel module parameters.

/sys/power/suspend/mode
-----------------------

Used to select the LP1 or LP0 power state during system suspend.
# echo lp0 > /sys/kernel/debug/suspend_mode
# echo lp1 > /sys/kernel/debug/suspend_mode

/sys/module/cpuidle/parameters/lp2_in_idle
------------------------------------------

Used to enable/disable LP2 in idle.
# echo 1 > /sys/module/cpuidle/parameters/lp2_in_idle
# echo 0 > /sys/module/cpuidle/parameters/lp2_in_idle

/sys/kernel/debug/cpuidle/lp2
-----------------------------

Contains LP2 statistics.
# cat /sys/kernel/debug/cpuidle/lp2

/sys/kernel/debug/powergate
---------------------------

Contains power gating state of different tegra blocks.

# cat /sys/kernel/debug/powergate

/sys/module/cpu_tegra3/parameters/auto_hotplug
----------------------------------------------

Used to control auto hotplug governor
# echo 0 >/sys/module/cpu_tegra3/parameters/auto_hotplug
# echo 1 >/sys/module/cpu_tegra3/parameters/auto_hotplug
# cat /sys/module/cpu_tegra3/parameters/auto_hotplug
0: disabled
1: idle
2: down
3: up

/sys/module/cpu_tegra3/parameters/no_lp
---------------------------------------

Used to enable/disable shadow cluster.
# echo 0 >/sys/module/cpu_tegra3/parameters/no_lp
# echo 1 >/sys/module/cpu_tegra3/parameters/no_lp

/sys/module/cpu_tegra3/parameters/idle_bottom_freq
--------------------------------------------------

Shadow cluster maximum frequency.

/sys/module/cpu_tegra3/parameters/idle_top_freq
-----------------------------------------------

Main cluster minimum frequency.

/sys/module/cpu_tegra3/parameters/down_delay
---------------------------------------------

Auto hotplug delay (in jiffies) for reducing cores.

/sys/module/cpu_tegra3/parameters/up2g0_delay
---------------------------------------------

Delay (in jiffies) for swithing to main cluster.

/sys/module/cpu_tegra3/parameters/up2gn_delay
---------------------------------------------

Delay (in jiffies) for bringing additional cores online in main
cluster.

/sys/module/cpu_tegra3/parameters/balance_level
-----------------------------------------------

Percentage of max speed considered to be in balance. Half of balanced
speed is considered skewed. Speed balance states:
* balanced: freq targets for all CPUs are above 50% of highest speed
* biased: freq target for at least one CPU is below 50% threshold
* skewed: freq targets for at least 2 CPUs are below 25% threshold
Speed balance state and hotplug state dictates auto hotlug behavior.

/sys/module/cpu_tegra3/parameters/mp_overhead
---------------------------------------------

Multi-core overhead percentage for EDP limit calculation.

/sys/kernel/debug/tegra_hotplug/stats
-------------------------------------

Contains hotplug statistics.

/sys/kernel/cluster/active
--------------------------

Controls active CPU cluster: main (G) or shadow (LP).
For manual control disable auto hotlug, enable immediate switch and
possibly force switch to happen always:
# echo 0 > /sys/module/cpu_tegra3/parameters/auto_hotplug
# echo 1 > /sys/kernel/cluster/immediate
# echo 1 > /sys/kernel/cluster/force

Cluster switching can happen only when only core 0 is online.

Active cluster can be set or toggled:
# echo "G" > /sys/kernel/cluster/active
# echo "LP" > /sys/kernel/cluster/active
# echo "toggle" > /sys/kernel/cluster/active

/sys/module/tegra3_clocks/parameters/detach_shared_bus
------------------------------------------------------

Enable/disable shared bus clock update.

/sys/module/tegra3_emc/parameters/emc_enable
--------------------------------------------

Enable/disable EMC DFS.

/sys/kernel/debug/tegra_emc/stats
---------------------------------

Contains EMC clock statistics.

/sys/module/tegra3_dvfs/parameters/disable_cpu
----------------------------------------------

Enable/disable DVFS for CPU domain.

/sys/module/tegra3_dvfs/parameters/disable_core
-----------------------------------------------

Enable/disable DVFS for CORE domain.

/sys/kernel/debug/clock/emc/rate
--------------------------------

Get/set EMC clock rate.

/sys/kernel/debug/clock/<module>/rate
-------------------------------------

/sys/kernel/debug/clock/<module>/parent
---------------------------------------

/sys/kernel/debug/clock/<module>/state
--------------------------------------

/sys/kernel/debug/clock/<module>/time_on
----------------------------------------

/sys/kernel/debug/clock/clock_tree
----------------------------------

Shows the state of the clock tree.

/sys/kernel/debug/clock/dvfs
----------------------------

Contains voltage state.

/sys/kernel/debug/tegra_actmon/avp/state
----------------------------------------

/sys/kernel/debug/clock/mon.avp/rate
------------------------------------

/sys/kernel/debug/clock/rails
-----------------------------

Contains the time at each voltage.

/sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
--------------------------------------------------------

Contains the time at each frequency.