1 /* SPDX-License-Identifier: GPL-2.0 */
14  * struct em_perf_state - Performance state of a performance domain
40  * struct em_perf_domain - Performance domain
51  * must have the same micro-architecture. Performance domains often have
52  * a 1-to-1 mapping with CPUFreq policies. In case of other devices the @cpus
65  *  EM_PERF_DOMAIN_MICROWATTS: The power values are in micro-Watts or some
78 #define em_span_cpus(em) (to_cpumask((em)->cpus))
79 #define em_is_artificial(em) ((em)->flags & EM_PERF_DOMAIN_ARTIFICIAL)
83  * The max power value in micro-Watts. The limit of 64 Watts is set as
106  * e.g. power ~1.3 Watt at max freq, so the 'cost' value > 1mln micro-Watts.
124 	 * active_power() - Provide power at the next performance state of
129 	 * @freq	: Frequency at the performance state in kHz
133 	 * 'freq' and update 'power' and 'freq' to the matching active power
137 	 * expressed in micro-Watts or an abstract scale. It is expected to
143 			    unsigned long *freq);
146 	 * get_cost() - Provide the cost at the given performance state of
149 	 * @freq	: Frequency at the performance state in kHz
159 	int (*get_cost)(struct device *dev, unsigned long freq,
177  * em_pd_get_efficient_state() - Get an efficient performance state from the EM
179  * @freq : Frequency to map with the EM
184  * Return: An efficient performance state, high enough to meet @freq
189 						unsigned long freq)  in em_pd_get_efficient_state()  argument
194 	for (i = 0; i < pd->nr_perf_states; i++) {  in em_pd_get_efficient_state()
195 		ps = &pd->table[i];  in em_pd_get_efficient_state()
196 		if (ps->frequency >= freq) {  in em_pd_get_efficient_state()
197 			if (pd->flags & EM_PERF_DOMAIN_SKIP_INEFFICIENCIES &&  in em_pd_get_efficient_state()
198 			    ps->flags & EM_PERF_STATE_INEFFICIENT)  in em_pd_get_efficient_state()
208  * em_cpu_energy() - Estimates the energy consumed by the CPUs of a
221  * a capacity state satisfying the max utilization of the domain.
227 	unsigned long freq, ref_freq, scale_cpu;  in em_cpu_energy()  local
239 	 * max utilization to the allowed CPU capacity before calculating  in em_cpu_energy()
242 	cpu = cpumask_first(to_cpumask(pd->cpus));  in em_cpu_energy()
247 	freq = map_util_freq(max_util, ref_freq, scale_cpu);  in em_cpu_energy()
253 	ps = em_pd_get_efficient_state(pd, freq);  in em_cpu_energy()
259 	 *             ps->freq * scale_cpu  in em_cpu_energy()
260 	 *   ps->cap = --------------------                          (1)  in em_cpu_energy()
267 	 *             ps->power * cpu_util  in em_cpu_energy()
268 	 *   cpu_nrg = --------------------                          (2)  in em_cpu_energy()
269 	 *                   ps->cap  in em_cpu_energy()
271 	 * since 'cpu_util / ps->cap' represents its percentage of busy time.  in em_cpu_energy()
278 	 * By injecting (1) in (2), 'cpu_nrg' can be re-expressed as a product  in em_cpu_energy()
281 	 *             ps->power * cpu_max_freq   cpu_util  in em_cpu_energy()
282 	 *   cpu_nrg = ------------------------ * ---------          (3)  in em_cpu_energy()
283 	 *                    ps->freq            scale_cpu  in em_cpu_energy()
286 	 * as 'ps->cost'.  in em_cpu_energy()
288 	 * Since all CPUs of the domain have the same micro-architecture, they  in em_cpu_energy()
289 	 * share the same 'ps->cost', and the same CPU capacity. Hence, the  in em_cpu_energy()
293 	 *            ps->cost * \Sum cpu_util  in em_cpu_energy()
294 	 *   pd_nrg = ------------------------                       (4)  in em_cpu_energy()
297 	return em_estimate_energy(ps->cost, sum_util, scale_cpu);  in em_cpu_energy()
301  * em_pd_nr_perf_states() - Get the number of performance states of a perf.
309 	return pd->nr_perf_states;  in em_pd_nr_perf_states()
323 	return -EINVAL;  in em_dev_register_perf_domain()