Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * linux/drivers/devfreq/governor_passive.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) 2016 Samsung Electronics
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Author: Chanwoo Choi <cw00.choi@samsung.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/devfreq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include "governor.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 					unsigned long *freq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 	struct devfreq_passive_data *p_data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 			= (struct devfreq_passive_data *)devfreq->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 	struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	unsigned long child_freq = ULONG_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	struct dev_pm_opp *opp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	int i, count, ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	 * If the devfreq device with passive governor has the specific method
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	 * to determine the next frequency, should use the get_target_freq()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	 * of struct devfreq_passive_data.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	if (p_data->get_target_freq) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 		ret = p_data->get_target_freq(devfreq, freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	 * If the parent and passive devfreq device uses the OPP table,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	 * get the next frequency by using the OPP table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	 * - parent devfreq device uses the governors except for passive.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	 * - passive devfreq device uses the passive governor.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	 * Each devfreq has the OPP table. After deciding the new frequency
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	 * from the governor of parent devfreq device, the passive governor
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	 * need to get the index of new frequency on OPP table of parent
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	 * device. And then the index is used for getting the suitable
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	 * new frequency for passive devfreq device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	if (!devfreq->profile || !devfreq->profile->freq_table
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 		|| devfreq->profile->max_state <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	 * The passive governor have to get the correct frequency from OPP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	 * list of parent device. Because in this case, *freq is temporary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	 * value which is decided by ondemand governor.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	opp = devfreq_recommended_opp(parent_devfreq->dev.parent, freq, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	if (IS_ERR(opp)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 		ret = PTR_ERR(opp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	dev_pm_opp_put(opp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	 * Get the OPP table's index of decided freqeuncy by governor
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	 * of parent device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	for (i = 0; i < parent_devfreq->profile->max_state; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 		if (parent_devfreq->profile->freq_table[i] == *freq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	if (i == parent_devfreq->profile->max_state) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	/* Get the suitable frequency by using index of parent device. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	if (i < devfreq->profile->max_state) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		child_freq = devfreq->profile->freq_table[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 		count = devfreq->profile->max_state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 		child_freq = devfreq->profile->freq_table[count - 1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	/* Return the suitable frequency for passive device. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	*freq = child_freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	if (!devfreq->governor)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	mutex_lock_nested(&devfreq->lock, SINGLE_DEPTH_NESTING);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	ret = devfreq->governor->get_target_freq(devfreq, &freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	ret = devfreq->profile->target(devfreq->dev.parent, &freq, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	if (devfreq->profile->freq_table
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 		&& (devfreq_update_status(devfreq, freq)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 		dev_err(&devfreq->dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 			"Couldn't update frequency transition information.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	devfreq->previous_freq = freq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	mutex_unlock(&devfreq->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) static int devfreq_passive_notifier_call(struct notifier_block *nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 				unsigned long event, void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	struct devfreq_passive_data *data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 			= container_of(nb, struct devfreq_passive_data, nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	struct devfreq *devfreq = (struct devfreq *)data->this;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	struct devfreq *parent = (struct devfreq *)data->parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	struct devfreq_freqs *freqs = (struct devfreq_freqs *)ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	unsigned long freq = freqs->new;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	switch (event) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	case DEVFREQ_PRECHANGE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 		if (parent->previous_freq > freq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 			update_devfreq_passive(devfreq, freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	case DEVFREQ_POSTCHANGE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 		if (parent->previous_freq < freq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 			update_devfreq_passive(devfreq, freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	return NOTIFY_DONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) static int devfreq_passive_event_handler(struct devfreq *devfreq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 				unsigned int event, void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	struct devfreq_passive_data *p_data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 			= (struct devfreq_passive_data *)devfreq->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	struct devfreq *parent = (struct devfreq *)p_data->parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	struct notifier_block *nb = &p_data->nb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	if (!parent)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		return -EPROBE_DEFER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	switch (event) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	case DEVFREQ_GOV_START:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 		if (!p_data->this)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 			p_data->this = devfreq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 		nb->notifier_call = devfreq_passive_notifier_call;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 		ret = devfreq_register_notifier(parent, nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 					DEVFREQ_TRANSITION_NOTIFIER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	case DEVFREQ_GOV_STOP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 		WARN_ON(devfreq_unregister_notifier(parent, nb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 					DEVFREQ_TRANSITION_NOTIFIER));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) static struct devfreq_governor devfreq_passive = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	.name = DEVFREQ_GOV_PASSIVE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	.immutable = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	.get_target_freq = devfreq_passive_get_target_freq,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	.event_handler = devfreq_passive_event_handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) static int __init devfreq_passive_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	return devfreq_add_governor(&devfreq_passive);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) subsys_initcall(devfreq_passive_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) static void __exit devfreq_passive_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 	ret = devfreq_remove_governor(&devfreq_passive);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 		pr_err("%s: failed remove governor %d\n", __func__, ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) module_exit(devfreq_passive_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) MODULE_DESCRIPTION("DEVFREQ Passive governor");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) MODULE_LICENSE("GPL v2");