1 # Copyright 2014-2015 ARM Limited 2 # 3 # Licensed under the Apache License, Version 2.0 (the "License"); 4 # you may not use this file except in compliance with the License. 5 # You may obtain a copy of the License at 6 # 7 # http://www.apache.org/licenses/LICENSE-2.0 8 # 9 # Unless required by applicable law or agreed to in writing, software 10 # distributed under the License is distributed on an "AS IS" BASIS, 11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 # See the License for the specific language governing permissions and 13 # limitations under the License. 14 # 15 # pylint: disable=attribute-defined-outside-init 16 from devlib.module import Module 17 from devlib.utils.misc import memoized 18 from devlib.utils.types import integer, boolean 19 20 21 class CpuidleState(object): 22 23 @property 24 def usage(self): 25 return integer(self.get('usage')) 26 27 @property 28 def time(self): 29 return integer(self.get('time')) 30 31 @property 32 def is_enabled(self): 33 return not boolean(self.get('disable')) 34 35 @property 36 def ordinal(self): 37 i = len(self.id) 38 while self.id[i - 1].isdigit(): 39 i -= 1 40 if not i: 41 raise ValueError('invalid idle state name: "{}"'.format(self.id)) 42 return int(self.id[i:]) 43 44 def __init__(self, target, index, path, name, desc, power, latency, residency): 45 self.target = target 46 self.index = index 47 self.path = path 48 self.name = name 49 self.desc = desc 50 self.power = power 51 self.latency = latency 52 self.id = self.target.path.basename(self.path) 53 self.cpu = self.target.path.basename(self.target.path.dirname(path)) 54 55 def enable(self): 56 self.set('disable', 0) 57 58 def disable(self): 59 self.set('disable', 1) 60 61 def get(self, prop): 62 property_path = self.target.path.join(self.path, prop) 63 return self.target.read_value(property_path) 64 65 def set(self, prop, value): 66 property_path = self.target.path.join(self.path, prop) 67 self.target.write_value(property_path, value) 68 69 def __eq__(self, other): 70 if isinstance(other, CpuidleState): 71 return (self.name == other.name) and (self.desc == other.desc) 72 elif isinstance(other, basestring): 73 return (self.name == other) or (self.desc == other) 74 else: 75 return False 76 77 def __ne__(self, other): 78 return not self.__eq__(other) 79 80 def __str__(self): 81 return 'CpuidleState({}, {})'.format(self.name, self.desc) 82 83 __repr__ = __str__ 84 85 86 class Cpuidle(Module): 87 88 name = 'cpuidle' 89 root_path = '/sys/devices/system/cpu/cpuidle' 90 91 @staticmethod 92 def probe(target): 93 return target.file_exists(Cpuidle.root_path) 94 95 def __init__(self, target): 96 super(Cpuidle, self).__init__(target) 97 self._states = {} 98 99 basepath = '/sys/devices/system/cpu/' 100 values_tree = self.target.read_tree_values(basepath, depth=4, check_exit_code=False) 101 i = 0 102 cpu_id = 'cpu{}'.format(i) 103 while cpu_id in values_tree: 104 cpu_node = values_tree[cpu_id] 105 106 if 'cpuidle' in cpu_node: 107 idle_node = cpu_node['cpuidle'] 108 self._states[cpu_id] = [] 109 j = 0 110 state_id = 'state{}'.format(j) 111 while state_id in idle_node: 112 state_node = idle_node[state_id] 113 state = CpuidleState( 114 self.target, 115 index=j, 116 path=self.target.path.join(basepath, cpu_id, 'cpuidle', state_id), 117 name=state_node['name'], 118 desc=state_node['desc'], 119 power=int(state_node['power']), 120 latency=int(state_node['latency']), 121 residency=int(state_node['residency']) if 'residency' in state_node else None, 122 ) 123 msg = 'Adding {} state {}: {} {}' 124 self.logger.debug(msg.format(cpu_id, j, state.name, state.desc)) 125 self._states[cpu_id].append(state) 126 j += 1 127 state_id = 'state{}'.format(j) 128 129 i += 1 130 cpu_id = 'cpu{}'.format(i) 131 132 def get_states(self, cpu=0): 133 if isinstance(cpu, int): 134 cpu = 'cpu{}'.format(cpu) 135 return self._states.get(cpu) 136 137 def get_state(self, state, cpu=0): 138 if isinstance(state, int): 139 try: 140 return self.get_states(cpu)[state] 141 except IndexError: 142 raise ValueError('Cpuidle state {} does not exist'.format(state)) 143 else: # assume string-like 144 for s in self.get_states(cpu): 145 if state in [s.id, s.name, s.desc]: 146 return s 147 raise ValueError('Cpuidle state {} does not exist'.format(state)) 148 149 def enable(self, state, cpu=0): 150 self.get_state(state, cpu).enable() 151 152 def disable(self, state, cpu=0): 153 self.get_state(state, cpu).disable() 154 155 def enable_all(self, cpu=0): 156 for state in self.get_states(cpu): 157 state.enable() 158 159 def disable_all(self, cpu=0): 160 for state in self.get_states(cpu): 161 state.disable() 162 163 def perturb_cpus(self): 164 """ 165 Momentarily wake each CPU. Ensures cpu_idle events in trace file. 166 """ 167 output = self.target._execute_util('cpuidle_wake_all_cpus') 168 print(output) 169 170 def get_driver(self): 171 return self.target.read_value(self.target.path.join(self.root_path, 'current_driver')) 172 173 def get_governor(self): 174 return self.target.read_value(self.target.path.join(self.root_path, 'current_governor_ro')) 175
