1 /* SPDX-License-Identifier: GPL-2.0 */
15  * struct em_perf_state - Performance state of a performance domain
16  * @performance:	CPU performance (capacity) at a given frequency
18  * @power:	The power consumed at this level (by 1 CPU or by a registered
43  * struct em_perf_table - Performance states table
55  * struct em_perf_domain - Performance domain
66  * In case of CPU device, a "performance domain" represents a group of CPUs
68  * must have the same micro-architecture. Performance domains often have
69  * a 1-to-1 mapping with CPUFreq policies. In case of other devices the @cpus
84  *  EM_PERF_DOMAIN_MICROWATTS: The power values are in micro-Watts or some
97 #define em_span_cpus(em) (to_cpumask((em)->cpus))
98 #define em_is_artificial(em) ((em)->flags & EM_PERF_DOMAIN_ARTIFICIAL)
102  * The max power value in micro-Watts. The limit of 64 Watts is set as
122 	 * active_power() - Provide power at the next performance state of
124 	 * @dev		: Device for which we do this operation (can be a CPU)
134 	 * In case of CPUs, the power is the one of a single CPU in the domain,
135 	 * expressed in micro-Watts or an abstract scale. It is expected to
144 	 * get_cost() - Provide the cost at the given performance state of
146 	 * @dev		: Device for which we do this operation (can be a CPU)
151 	 * In case of CPUs, the cost is the one of a single CPU in the domain.
167 struct em_perf_domain *em_cpu_get(int cpu);
185  * em_pd_get_efficient_state() - Get an efficient performance state from the EM
200 	unsigned long pd_flags = pd->flags;  in em_pd_get_efficient_state()
201 	int min_ps = pd->min_perf_state;  in em_pd_get_efficient_state()
202 	int max_ps = pd->max_perf_state;  in em_pd_get_efficient_state()
208 		if (ps->performance >= max_util) {  in em_pd_get_efficient_state()
210 			    ps->flags & EM_PERF_STATE_INEFFICIENT)  in em_pd_get_efficient_state()
220  * em_cpu_energy() - Estimates the energy consumed by the CPUs of a
225  * @allowed_cpu_cap	: maximum allowed CPU capacity for the @pd, which
228  * This function must be used only for CPU devices. There is no validation,
229  * i.e. if the EM is a CPU type and has cpumask allocated. It is called from
233  * a capacity state satisfying the max utilization of the domain.
252 	 * the most utilized CPU of the performance domain to a requested  in em_cpu_energy()
255 	 * max utilization to the allowed CPU capacity before calculating  in em_cpu_energy()
264 	em_table = rcu_dereference(pd->em_table);  in em_cpu_energy()
265 	i = em_pd_get_efficient_state(em_table->state, pd, max_util);  in em_cpu_energy()
266 	ps = &em_table->state[i];  in em_cpu_energy()
269 	 * The performance (capacity) of a CPU in the domain at the performance  in em_cpu_energy()
272 	 *                     ps->freq * scale_cpu  in em_cpu_energy()
273 	 *   ps->performance = --------------------                  (1)  in em_cpu_energy()
277 	 * the EM), the energy consumed by this CPU at that performance state  in em_cpu_energy()
280 	 *             ps->power * cpu_util  in em_cpu_energy()
281 	 *   cpu_nrg = --------------------                          (2)  in em_cpu_energy()
282 	 *               ps->performance  in em_cpu_energy()
284 	 * since 'cpu_util / ps->performance' represents its percentage of busy  in em_cpu_energy()
292 	 * By injecting (1) in (2), 'cpu_nrg' can be re-expressed as a product  in em_cpu_energy()
295 	 *             ps->power * cpu_max_freq  in em_cpu_energy()
296 	 *   cpu_nrg = ------------------------ * cpu_util           (3)  in em_cpu_energy()
297 	 *               ps->freq * scale_cpu  in em_cpu_energy()
300 	 * as 'ps->cost'.  in em_cpu_energy()
302 	 * Since all CPUs of the domain have the same micro-architecture, they  in em_cpu_energy()
303 	 * share the same 'ps->cost', and the same CPU capacity. Hence, the  in em_cpu_energy()
307 	 *   pd_nrg = ps->cost * \Sum cpu_util                       (4)  in em_cpu_energy()
309 	return ps->cost * sum_util;  in em_cpu_energy()
313  * em_pd_nr_perf_states() - Get the number of performance states of a perf.
321 	return pd->nr_perf_states;  in em_pd_nr_perf_states()
325  * em_perf_state_from_pd() - Get the performance states table of perf.
338 	return rcu_dereference(pd->em_table)->state;  in em_perf_state_from_pd()
352 	return -EINVAL;  in em_dev_register_perf_domain()
357 static inline struct em_perf_domain *em_cpu_get(int cpu)  in em_cpu_get()  argument
385 	return -EINVAL;  in em_dev_update_perf_domain()
396 	return -EINVAL;  in em_dev_compute_costs()
400 	return -EINVAL;  in em_dev_update_chip_binning()
406 	return -EINVAL;  in em_update_performance_limits()