Lines Matching +full:micro +full:- +full:watts
1 .. SPDX-License-Identifier: GPL-2.0
8 -----------
12 subsystems willing to use that information to make energy-aware decisions.
18 each and every client subsystem to re-implement support for each and every
23 The power values might be expressed in micro-Watts or in an 'abstract scale'.
26 can be found in the Energy-Aware Scheduler documentation
27 Documentation/scheduler/sched-energy.rst. For some subsystems like thermal or
30 thus the real micro-Watts might be needed. An example of these requirements can
32 Documentation/driver-api/thermal/power_allocator.rst.
36 an 'abstract scale' deriving real energy in micro-Joules would not be possible.
38 The figure below depicts an example of drivers (Arm-specific here, but the
42 +---------------+ +-----------------+ +---------------+
44 +---------------+ +-----------------+ +---------------+
47 +---------+ | +---------+
50 +---------------------+
53 +---------------------+
56 +----------+ | +---------+
58 +---------------+ +---------------+ +--------------+
59 | cpufreq-dt | | arm_scmi | | Other |
60 +---------------+ +---------------+ +--------------+
63 +--------------+ +---------------+ +--------------+
65 +--------------+ +---------------+ +--------------+
70 1-to-1 mapping with CPUFreq policies. All CPUs in a performance domain are
71 required to have the same micro-architecture. CPUs in different performance
72 domains can have different micro-architectures.
83 framework will handle the clean-up when it's possible.
101 ------------
145 "operating-points-v2". Each OPP entry in DT can be extended with a property
146 "opp-microwatt" containing micro-Watts power value. This OPP DT property
230 and will be visible to other sub-systems in the kernel (thermal, powercap).
232 or memory allocations at runtime. When pre-computed EMs are available in the
233 device driver, than it should be possible to simply re-use them with low
242 no other sub-system using it, e.g. EAS.
244 To use the power values in other sub-systems (like thermal, powercap) there is
280 .. kernel-doc:: include/linux/energy_model.h
283 .. kernel-doc:: kernel/power/energy_model.c
288 -----------
302 -> drivers/cpufreq/foo_cpufreq.c
332 29 cpu_dev = get_cpu_device(cpumask_first(policy->cpus));
338 35 em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb, policy->cpus,
354 -> drivers/soc/example/example_em_mod.c
360 05 struct device *dev = ctx->dev;
373 18 new_table = em_table->state;
377 22 for (i = 0; i < pd->nr_perf_states; i++) {
384 29 ret = em_dev_compute_costs(dev, table, pd->nr_perf_states);
399 44 * Since it's one-time-update drop the usage counter.
411 56 struct device *dev = ctx->dev;
414 59 ctx->temperature = foo_get_temp(dev, ctx);
415 60 if (ctx->temperature < FOO_EM_UPDATE_TEMP_THRESHOLD)