1 // SPDX-License-Identifier: GPL-2.0-only
3  * intel_powerclamp.c - package c-state idle injection
5  * Copyright (c) 2012-2023, Intel Corporation.
16  *              cpu in non-irq context does not reduce irq. for majority of the
56 /* Idle ratio observed using package C-state counters */
91 		pr_err("Out of recommended range %lu, between 6-25ms\n",  in duration_set()
93 		ret = -EINVAL;  in duration_set()
98 	duration = clamp(new_duration, 6ul, 25ul) * 1000;  in duration_set()
110 	ret = sysfs_emit(buf, "%d\n", duration / 1000);  in duration_get()
138 		return -ENOMEM;  in allocate_copy_idle_injection_mask()
164 		ret = -EAGAIN;  in cpumask_set()
178 		ret = -EINVAL;  in cpumask_set()
202 		return -ENODEV;  in cpumask_get()
225 		ret = -EAGAIN;  in max_idle_set()
234 		ret = -EINVAL;  in max_idle_set()
245 		ret = -EINVAL;  in max_idle_set()
263 …RM_DESC(max_idle, "maximum injected idle time to the total CPU time ratio in percent range:1-100");
291 		pr_err("Out of recommended window size %lu, between 2-10\n",  in window_size_set()
293 		ret = -EINVAL;  in window_size_set()
317 	unsigned int eax, ebx, ecx, edx;  in find_target_mwait()  local
325 	cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);  in find_target_mwait()
327 	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||  in find_target_mwait()
328 	    !(ecx & CPUID5_ECX_INTERRUPT_BREAK))  in find_target_mwait()
339 		(highest_subcstate - 1);  in find_target_mwait()
371 	while (info->msr_index) {  in has_pkg_state_counter()
372 		if (!rdmsrl_safe(info->msr_index, &val))  in has_pkg_state_counter()
386 	while (info->msr_index) {  in pkg_state_counter()
387 		if (!info->skip) {  in pkg_state_counter()
388 			if (!rdmsrl_safe(info->msr_index, &val))  in pkg_state_counter()
391 				info->skip = true;  in pkg_state_counter()
414 	} else if (ratio == MAX_TARGET_RATIO - 1 &&  in get_compensation()
416 		cal_data[ratio - 1].confidence >= CONFIDENCE_OK &&  in get_compensation()
417 		cal_data[ratio - 2].confidence >= CONFIDENCE_OK) {  in get_compensation()
419 			cal_data[ratio - 1].steady_comp +  in get_compensation()
420 			cal_data[ratio - 2].steady_comp) / 3;  in get_compensation()
422 		cal_data[ratio - 1].confidence >= CONFIDENCE_OK &&  in get_compensation()
425 			cal_data[ratio - 1].steady_comp +  in get_compensation()
431 		comp = MAX_TARGET_RATIO - ratio - 1;  in get_compensation()
444 	if (d->confidence >= CONFIDENCE_OK)  in adjust_compensation()
447 	delta = powerclamp_data.target_ratio - current_ratio;  in adjust_compensation()
450 		if (d->steady_comp)  in adjust_compensation()
451 			d->steady_comp =  in adjust_compensation()
452 				roundup(delta+d->steady_comp, 2)/2;  in adjust_compensation()
454 			d->steady_comp = delta;  in adjust_compensation()
455 		d->confidence++;  in adjust_compensation()
473 	else if (tsc_now-tsc_last) {  in powerclamp_adjust_controls()
474 		val64 = 100*(msr_now-msr_last);  in powerclamp_adjust_controls()
475 		do_div(val64, (tsc_now-tsc_last));  in powerclamp_adjust_controls()
508 	 * c-states, thus we need to compensate the injected idle ratio  in get_run_time()
516 	runtime = duration * 100 / compensated_ratio - duration;  in get_run_time()
543 		if (tsc_now - tsc_last) {  in poll_pkg_cstate()
544 			val64 = 100 * (msr_now - msr_last);  in poll_pkg_cstate()
545 			do_div(val64, (tsc_now - tsc_last));  in poll_pkg_cstate()
627 		return -EAGAIN;  in powerclamp_idle_injection_register()
705 				(unsigned long) (max_idle - 1));  in powerclamp_set_cur_state()
753 		return -ENODEV;  in powerclamp_probe()
758 		pr_info("No package C-state available\n");  in powerclamp_probe()
759 		return -ENODEV;  in powerclamp_probe()
817 		return -ENODEV;  in powerclamp_init()
849 MODULE_DESCRIPTION("Package Level C-state Idle Injection for Intel CPUs");