39ab662df761c0ad3490cdb7660424645f01c065
[linux-2.6.git] / Documentation / arm / nvidia / tegra_parameters.txt
1 This file documents NVIDIA Tegra specific sysfs and debugfs files and
2 kernel module parameters.
3
4 /sys/power/suspend/mode
5 -----------------------
6
7 Used to select the LP1 or LP0 power state during system suspend.
8 # echo lp0 > /sys/kernel/debug/suspend_mode
9 # echo lp1 > /sys/kernel/debug/suspend_mode
10
11 /sys/module/cpuidle/parameters/lp2_in_idle
12 ------------------------------------------
13
14 Used to enable/disable LP2 in idle.
15 # echo 1 > /sys/module/cpuidle/parameters/lp2_in_idle
16 # echo 0 > /sys/module/cpuidle/parameters/lp2_in_idle
17
18 /sys/kernel/debug/cpuidle/lp2
19 -----------------------------
20
21 Contains LP2 statistics.
22 # cat /sys/kernel/debug/cpuidle/lp2
23
24 /sys/kernel/debug/powergate
25 ---------------------------
26
27 Contains power gating state of different tegra blocks.
28
29 # cat /sys/kernel/debug/powergate
30
31 /sys/module/cpu_tegra3/parameters/auto_hotplug
32 ----------------------------------------------
33
34 Used to control auto hotplug governor
35 # echo 0 >/sys/module/cpu_tegra3/parameters/auto_hotplug
36 # echo 1 >/sys/module/cpu_tegra3/parameters/auto_hotplug
37 # cat /sys/module/cpu_tegra3/parameters/auto_hotplug
38 0: disabled
39 1: idle
40 2: down
41 3: up
42
43 /sys/module/cpu_tegra3/parameters/no_lp
44 ---------------------------------------
45
46 Used to enable/disable shadow cluster.
47 # echo 0 >/sys/module/cpu_tegra3/parameters/no_lp
48 # echo 1 >/sys/module/cpu_tegra3/parameters/no_lp
49
50 /sys/module/cpu_tegra3/parameters/idle_bottom_freq
51 --------------------------------------------------
52
53 Shadow cluster maximum frequency.
54
55 /sys/module/cpu_tegra3/parameters/idle_top_freq
56 -----------------------------------------------
57
58 Main cluster minimum frequency.
59
60 /sys/module/cpu_tegra3/parameters/down_delay
61 ---------------------------------------------
62
63 Auto hotplug delay (in jiffies) for reducing cores.
64
65 /sys/module/cpu_tegra3/parameters/up2g0_delay
66 ---------------------------------------------
67
68 Delay (in jiffies) for swithing to main cluster.
69
70 /sys/module/cpu_tegra3/parameters/up2gn_delay
71 ---------------------------------------------
72
73 Delay (in jiffies) for bringing additional cores online in main
74 cluster.
75
76 /sys/module/cpu_tegra3/parameters/balance_level
77 -----------------------------------------------
78
79 Percentage of max speed considered to be in balance. Half of balanced
80 speed is considered skewed. Speed balance states:
81 * balanced: freq targets for all CPUs are above 50% of highest speed
82 * biased: freq target for at least one CPU is below 50% threshold
83 * skewed: freq targets for at least 2 CPUs are below 25% threshold
84 Speed balance state and hotplug state dictates auto hotlug behavior.
85
86 /sys/module/cpu_tegra3/parameters/mp_overhead
87 ---------------------------------------------
88
89 Multi-core overhead percentage for EDP limit calculation.
90
91 /sys/kernel/debug/tegra_hotplug/stats
92 -------------------------------------
93
94 Contains hotplug statistics.
95
96 /sys/kernel/cluster/active
97 --------------------------
98
99 Controls active CPU cluster: main (G) or shadow (LP).
100 For manual control disable auto hotlug, enable immediate switch and
101 possibly force switch to happen always:
102 # echo 0 > /sys/module/cpu_tegra3/parameters/auto_hotplug
103 # echo 1 > /sys/kernel/cluster/immediate
104 # echo 1 > /sys/kernel/cluster/force
105
106 Cluster switching can happen only when only core 0 is online.
107
108 Active cluster can be set or toggled:
109 # echo "G" > /sys/kernel/cluster/active
110 # echo "LP" > /sys/kernel/cluster/active
111 # echo "toggle" > /sys/kernel/cluster/active
112
113 /sys/module/tegra3_clocks/parameters/detach_shared_bus
114 ------------------------------------------------------
115
116 Enable/disable shared bus clock update.
117
118 /sys/module/tegra3_emc/parameters/emc_enable
119 --------------------------------------------
120
121 Enable/disable EMC DFS.
122
123 /sys/kernel/debug/tegra_emc/stats
124 ---------------------------------
125
126 Contains EMC clock statistics.
127
128 /sys/module/tegra3_dvfs/parameters/disable_cpu
129 ----------------------------------------------
130
131 Enable/disable DVFS for CPU domain.
132
133 /sys/module/tegra3_dvfs/parameters/disable_core
134 -----------------------------------------------
135
136 Enable/disable DVFS for CORE domain.
137
138 /sys/kernel/debug/clock/emc/rate
139 --------------------------------
140
141 Get/set EMC clock rate.
142
143 /sys/kernel/debug/clock/<module>/rate
144 -------------------------------------
145
146 /sys/kernel/debug/clock/<module>/parent
147 ---------------------------------------
148
149 /sys/kernel/debug/clock/<module>/state
150 --------------------------------------
151
152 /sys/kernel/debug/clock/<module>/time_on
153 ----------------------------------------
154
155 /sys/kernel/debug/clock/clock_tree
156 ----------------------------------
157
158 Shows the state of the clock tree.
159
160 /sys/kernel/debug/clock/dvfs
161 ----------------------------
162
163 Contains voltage state.
164
165 /sys/kernel/debug/tegra_actmon/avp/state
166 ----------------------------------------
167
168 /sys/kernel/debug/clock/mon.avp/rate
169 ------------------------------------
170
171 /sys/kernel/debug/clock/rails
172 -----------------------------
173
174 Contains the time at each voltage.
175
176 /sys/devices/system/cpu/cpu0/cpufreq/stats/time_in_state
177 --------------------------------------------------------
178
179 Contains the time at each frequency.