1 // SPDX-License-Identifier: GPL-2.0-only
3  * Generic Exynos Bus frequency driver with DEVFREQ Framework
9  * DEVFREQ framework and is based on drivers/devfreq/exynos/exynos4_bus.c.
13 #include <linux/devfreq.h>
14 #include <linux/devfreq-event.h>
28 	struct devfreq *devfreq;  member
41  * Control the devfreq-event device to get the current state of bus
48 	for (i = 0; i < bus->edev_count; i++) {			\
49 		if (!bus->edev[i])				\
51 		ret = devfreq_event_##ops(bus->edev[i]);	\
69 	for (i = 0; i < bus->edev_count; i++) {  in exynos_bus_get_event()
70 		if (!bus->edev[i])  in exynos_bus_get_event()
73 		ret = devfreq_event_get_event(bus->edev[i], &event_data);  in exynos_bus_get_event()
83 	edata->load_count = load_count;  in exynos_bus_get_event()
84 	edata->total_count = total_count;  in exynos_bus_get_event()
90  * devfreq function for both simple-ondemand and passive governor
108 	mutex_lock(&bus->lock);  in exynos_bus_target()
111 		bus->curr_freq = *freq;  in exynos_bus_target()
113 	mutex_unlock(&bus->lock);  in exynos_bus_target()
125 	stat->current_frequency = bus->curr_freq;  in exynos_bus_get_dev_status()
129 		dev_err(dev, "failed to get event from devfreq-event devices\n");  in exynos_bus_get_dev_status()
130 		stat->total_time = stat->busy_time = 0;  in exynos_bus_get_dev_status()
134 	stat->busy_time = (edata.load_count * 100) / bus->ratio;  in exynos_bus_get_dev_status()
135 	stat->total_time = edata.total_count;  in exynos_bus_get_dev_status()
137 	dev_dbg(dev, "Usage of devfreq-event : %lu/%lu\n", stat->busy_time,  in exynos_bus_get_dev_status()
138 							stat->total_time);  in exynos_bus_get_dev_status()
143 		dev_err(dev, "failed to set event to devfreq-event devices\n");  in exynos_bus_get_dev_status()
157 		dev_warn(dev, "failed to disable the devfreq-event devices\n");  in exynos_bus_exit()
160 	clk_disable_unprepare(bus->clk);  in exynos_bus_exit()
161 	if (bus->opp_table) {  in exynos_bus_exit()
162 		dev_pm_opp_put_regulators(bus->opp_table);  in exynos_bus_exit()
163 		bus->opp_table = NULL;  in exynos_bus_exit()
172 	clk_disable_unprepare(bus->clk);  in exynos_bus_passive_exit()
178 	struct device *dev = bus->dev;  in exynos_bus_parent_parse_of()
190 	bus->opp_table = opp_table;  in exynos_bus_parent_parse_of()
193 	 * Get the devfreq-event devices to get the current utilization of  in exynos_bus_parent_parse_of()
194 	 * buses. This raw data will be used in devfreq ondemand governor.  in exynos_bus_parent_parse_of()
196 	count = devfreq_event_get_edev_count(dev, "devfreq-events");  in exynos_bus_parent_parse_of()
198 		dev_err(dev, "failed to get the count of devfreq-event dev\n");  in exynos_bus_parent_parse_of()
202 	bus->edev_count = count;  in exynos_bus_parent_parse_of()
204 	size = sizeof(*bus->edev) * count;  in exynos_bus_parent_parse_of()
205 	bus->edev = devm_kzalloc(dev, size, GFP_KERNEL);  in exynos_bus_parent_parse_of()
206 	if (!bus->edev) {  in exynos_bus_parent_parse_of()
207 		ret = -ENOMEM;  in exynos_bus_parent_parse_of()
212 		bus->edev[i] = devfreq_event_get_edev_by_phandle(dev,  in exynos_bus_parent_parse_of()
213 							"devfreq-events", i);  in exynos_bus_parent_parse_of()
214 		if (IS_ERR(bus->edev[i])) {  in exynos_bus_parent_parse_of()
215 			ret = -EPROBE_DEFER;  in exynos_bus_parent_parse_of()
222 	 * When measuring the utilization of each AXI bus with devfreq-event  in exynos_bus_parent_parse_of()
224 	 * total cycle of bus during sampling rate. In result, the devfreq  in exynos_bus_parent_parse_of()
225 	 * simple-ondemand governor might not decide to change the current  in exynos_bus_parent_parse_of()
230 	if (of_property_read_u32(np, "exynos,saturation-ratio", &bus->ratio))  in exynos_bus_parent_parse_of()
231 		bus->ratio = DEFAULT_SATURATION_RATIO;  in exynos_bus_parent_parse_of()
236 	dev_pm_opp_put_regulators(bus->opp_table);  in exynos_bus_parent_parse_of()
237 	bus->opp_table = NULL;  in exynos_bus_parent_parse_of()
245 	struct device *dev = bus->dev;  in exynos_bus_parse_of()
251 	bus->clk = devm_clk_get(dev, "bus");  in exynos_bus_parse_of()
252 	if (IS_ERR(bus->clk)) {  in exynos_bus_parse_of()
254 		return PTR_ERR(bus->clk);  in exynos_bus_parse_of()
257 	ret = clk_prepare_enable(bus->clk);  in exynos_bus_parse_of()
270 	rate = clk_get_rate(bus->clk);  in exynos_bus_parse_of()
278 	bus->curr_freq = dev_pm_opp_get_freq(opp);  in exynos_bus_parse_of()
286 	clk_disable_unprepare(bus->clk);  in exynos_bus_parse_of()
294 	struct device *dev = bus->dev;  in exynos_bus_profile_init()
299 	profile->polling_ms = 50;  in exynos_bus_profile_init()
300 	profile->target = exynos_bus_target;  in exynos_bus_profile_init()
301 	profile->get_dev_status = exynos_bus_get_dev_status;  in exynos_bus_profile_init()
302 	profile->exit = exynos_bus_exit;  in exynos_bus_profile_init()
306 		return -ENOMEM;  in exynos_bus_profile_init()
308 	ondemand_data->upthreshold = 40;  in exynos_bus_profile_init()
309 	ondemand_data->downdifferential = 5;  in exynos_bus_profile_init()
311 	/* Add devfreq device to monitor and handle the exynos bus */  in exynos_bus_profile_init()
312 	bus->devfreq = devm_devfreq_add_device(dev, profile,  in exynos_bus_profile_init()
315 	if (IS_ERR(bus->devfreq)) {  in exynos_bus_profile_init()
316 		dev_err(dev, "failed to add devfreq device\n");  in exynos_bus_profile_init()
317 		return PTR_ERR(bus->devfreq);  in exynos_bus_profile_init()
321 	ret = devm_devfreq_register_opp_notifier(dev, bus->devfreq);  in exynos_bus_profile_init()
328 	 * Enable devfreq-event to get raw data which is used to determine  in exynos_bus_profile_init()
333 		dev_err(dev, "failed to enable devfreq-event devices\n");  in exynos_bus_profile_init()
339 		dev_err(dev, "failed to set event to devfreq-event devices\n");  in exynos_bus_profile_init()
347 		dev_warn(dev, "failed to disable the devfreq-event devices\n");  in exynos_bus_profile_init()
355 	struct device *dev = bus->dev;  in exynos_bus_profile_init_passive()
357 	struct devfreq *parent_devfreq;  in exynos_bus_profile_init_passive()
360 	profile->target = exynos_bus_target;  in exynos_bus_profile_init_passive()
361 	profile->exit = exynos_bus_passive_exit;  in exynos_bus_profile_init_passive()
363 	/* Get the instance of parent devfreq device */  in exynos_bus_profile_init_passive()
364 	parent_devfreq = devfreq_get_devfreq_by_phandle(dev, "devfreq", 0);  in exynos_bus_profile_init_passive()
366 		return -EPROBE_DEFER;  in exynos_bus_profile_init_passive()
370 		return -ENOMEM;  in exynos_bus_profile_init_passive()
372 	passive_data->parent = parent_devfreq;  in exynos_bus_profile_init_passive()
374 	/* Add devfreq device for exynos bus with passive governor */  in exynos_bus_profile_init_passive()
375 	bus->devfreq = devm_devfreq_add_device(dev, profile, DEVFREQ_GOV_PASSIVE,  in exynos_bus_profile_init_passive()
377 	if (IS_ERR(bus->devfreq)) {  in exynos_bus_profile_init_passive()
379 			"failed to add devfreq dev with passive governor\n");  in exynos_bus_profile_init_passive()
380 		return PTR_ERR(bus->devfreq);  in exynos_bus_profile_init_passive()
388 	struct device *dev = &pdev->dev;  in exynos_bus_probe()
389 	struct device_node *np = dev->of_node, *node;  in exynos_bus_probe()
398 		return -EINVAL;  in exynos_bus_probe()
401 	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);  in exynos_bus_probe()
403 		return -ENOMEM;  in exynos_bus_probe()
404 	mutex_init(&bus->lock);  in exynos_bus_probe()
405 	bus->dev = &pdev->dev;  in exynos_bus_probe()
410 		return -ENOMEM;  in exynos_bus_probe()
412 	node = of_parse_phandle(dev->of_node, "devfreq", 0);  in exynos_bus_probe()
422 	/* Parse the device-tree to get the resource information */  in exynos_bus_probe()
435 	max_state = bus->devfreq->profile->max_state;  in exynos_bus_probe()
436 	min_freq = (bus->devfreq->profile->freq_table[0] / 1000);  in exynos_bus_probe()
437 	max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);  in exynos_bus_probe()
438 	pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",  in exynos_bus_probe()
445 	clk_disable_unprepare(bus->clk);  in exynos_bus_probe()
448 		dev_pm_opp_put_regulators(bus->opp_table);  in exynos_bus_probe()
449 		bus->opp_table = NULL;  in exynos_bus_probe()
457 	struct exynos_bus *bus = dev_get_drvdata(&pdev->dev);  in exynos_bus_shutdown()
459 	devfreq_suspend_device(bus->devfreq);  in exynos_bus_shutdown()
470 		dev_err(dev, "failed to enable the devfreq-event devices\n");  in exynos_bus_resume()
484 		dev_err(dev, "failed to disable the devfreq-event devices\n");  in exynos_bus_suspend()
497 	{ .compatible = "samsung,exynos-bus", },
506 		.name	= "exynos-bus",