From 6d87641e1842128eba6fbc05ba16d2cb12674a3f Mon Sep 17 00:00:00 2001 From: Antti P Miettinen Date: Sun, 1 Jan 2012 13:41:40 +0200 Subject: ARM: tegra: Document sysfs/debugfs/module params Bug 894311 Change-Id: I376a03adc2088a9b1b0b19168f72dbcb770e6ad2 Signed-off-by: Antti P Miettinen Reviewed-on: http://git-master/r/83497 Reviewed-by: Juha Tukkinen --- Documentation/arm/nvidia/tegra_parameters.txt | 169 ++++++++++++++++++++++++++ 1 file changed, 169 insertions(+) create mode 100644 Documentation/arm/nvidia/tegra_parameters.txt (limited to 'Documentation') diff --git a/Documentation/arm/nvidia/tegra_parameters.txt b/Documentation/arm/nvidia/tegra_parameters.txt new file mode 100644 index 000000000000..4c73fe7269f3 --- /dev/null +++ b/Documentation/arm/nvidia/tegra_parameters.txt @@ -0,0 +1,169 @@ +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//rate +------------------------------------- + +/sys/kernel/debug/clock//parent +--------------------------------------- + +/sys/kernel/debug/clock//state +-------------------------------------- + +/sys/kernel/debug/clock//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 +------------------------------------ -- cgit v1.2.3