1 // SPDX-License-Identifier: GPL-2.0-only
22 #include <asm/intel-family.h>
58  * Since the frequency freq_curr on x86 is controlled by micro-controller and
59  * our P-state setting is little more than a request/hint, we need to observe
65  * where freq_base is the max non-turbo P-state.
68  * can't know which turbo states will be available at a given point in time:
70  * the turbo level with 4 cores active.
72  * Benchmarks show that's a good compromise between the 1C turbo ratio
74  * which would ignore the entire turbo range (a conspicuous part, making
75  * freq_curr/freq_max always maxed out).
78  * highest turbo level for freq_max since Atom's are generally oriented towards
81  * Setting freq_max to anything less than the 1C turbo ratio makes the ratio
122 	*turbo_freq = *turbo_freq & 0x3F;           /* 1C turbo    */  in slv_set_max_freq_ratio()
178 			fratio -= delta_fratio;  in knl_set_max_freq_ratio()
232 	*turbo_freq = (msr >> 24) & 0xFF;         /* 4C turbo    */  in core_set_max_freq_ratio()
236 		*turbo_freq = msr & 0xFF;         /* 1C turbo    */  in core_set_max_freq_ratio()
270 	 * Some CPUs have turbo boost but don't declare any turbo ratio  in intel_set_max_freq_ratio()
274 …pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting…  in intel_set_max_freq_ratio()
280 		pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n");  in intel_set_max_freq_ratio()
362  * arch_enable_hybrid_capacity_scale() - Enable hybrid CPU capacity scaling
364  * Allocate memory for per-CPU data used by hybrid CPU capacity scaling,
383 		per_cpu_ptr(arch_cpu_scale, cpu)->capacity = SCHED_CAPACITY_SCALE;  in arch_enable_hybrid_capacity_scale()
384 		per_cpu_ptr(arch_cpu_scale, cpu)->freq_ratio = arch_max_freq_ratio;  in arch_enable_hybrid_capacity_scale()
395  * arch_set_cpu_capacity() - Set scale-invariance parameters for a CPU
398  * @max_cap: System-wide maximum CPU capacity.
407  * to let the scheduler know that capacity-aware scheduling can be used going
414 		WRITE_ONCE(per_cpu_ptr(arch_cpu_scale, cpu)->capacity,  in arch_set_cpu_capacity()
416 		WRITE_ONCE(per_cpu_ptr(arch_cpu_scale, cpu)->freq_ratio,  in arch_set_cpu_capacity()
426 		return READ_ONCE(per_cpu_ptr(arch_cpu_scale, cpu)->capacity);  in arch_scale_cpu_capacity()
443 		freq_ratio = READ_ONCE(this_cpu_ptr(arch_cpu_scale)->freq_ratio);  in scale_freq_tick()
479 	acnt = aperf - s->aperf;  in arch_scale_freq_tick()
480 	mcnt = mperf - s->mperf;  in arch_scale_freq_tick()
482 	s->aperf = aperf;  in arch_scale_freq_tick()
483 	s->mperf = mperf;  in arch_scale_freq_tick()
485 	raw_write_seqcount_begin(&s->seq);  in arch_scale_freq_tick()
486 	s->last_update = jiffies;  in arch_scale_freq_tick()
487 	s->acnt = acnt;  in arch_scale_freq_tick()
488 	s->mcnt = mcnt;  in arch_scale_freq_tick()
489 	raw_write_seqcount_end(&s->seq);  in arch_scale_freq_tick()
512 		seq = raw_read_seqcount_begin(&s->seq);  in arch_freq_get_on_cpu()
513 		last = s->last_update;  in arch_freq_get_on_cpu()
514 		acnt = s->acnt;  in arch_freq_get_on_cpu()
515 		mcnt = s->mcnt;  in arch_freq_get_on_cpu()
516 	} while (read_seqcount_retry(&s->seq, seq));  in arch_freq_get_on_cpu()
522 	if (!mcnt || (jiffies - last) > MAX_SAMPLE_AGE)  in arch_freq_get_on_cpu()