| /* |
| * Copyright (c) 2012 Samsung Electronics Co., Ltd. |
| * http://www.samsung.com/ |
| * |
| * EXYNOS5 INT clock frequency scaling support using DEVFREQ framework |
| * Based on work done by Jonghwan Choi <jhbird.choi@samsung.com> |
| * Support for only EXYNOS5250 is present. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/devfreq.h> |
| #include <linux/io.h> |
| #include <linux/pm_opp.h> |
| #include <linux/slab.h> |
| #include <linux/suspend.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_qos.h> |
| #include <linux/regulator/consumer.h> |
| #include <linux/of_address.h> |
| #include <linux/of_platform.h> |
| |
| #include "exynos_ppmu.h" |
| |
| #define MAX_SAFEVOLT 1100000 /* 1.10V */ |
| /* Assume that the bus is saturated if the utilization is 25% */ |
| #define INT_BUS_SATURATION_RATIO 25 |
| |
| enum int_level_idx { |
| LV_0, |
| LV_1, |
| LV_2, |
| LV_3, |
| LV_4, |
| _LV_END |
| }; |
| |
| enum exynos_ppmu_list { |
| PPMU_RIGHT, |
| PPMU_END, |
| }; |
| |
| struct busfreq_data_int { |
| struct device *dev; |
| struct devfreq *devfreq; |
| struct regulator *vdd_int; |
| struct exynos_ppmu ppmu[PPMU_END]; |
| unsigned long curr_freq; |
| bool disabled; |
| |
| struct notifier_block pm_notifier; |
| struct mutex lock; |
| struct pm_qos_request int_req; |
| struct clk *int_clk; |
| }; |
| |
| struct int_bus_opp_table { |
| unsigned int idx; |
| unsigned long clk; |
| unsigned long volt; |
| }; |
| |
| static struct int_bus_opp_table exynos5_int_opp_table[] = { |
| {LV_0, 266000, 1025000}, |
| {LV_1, 200000, 1025000}, |
| {LV_2, 160000, 1025000}, |
| {LV_3, 133000, 1025000}, |
| {LV_4, 100000, 1025000}, |
| {0, 0, 0}, |
| }; |
| |
| static void busfreq_mon_reset(struct busfreq_data_int *data) |
| { |
| unsigned int i; |
| |
| for (i = PPMU_RIGHT; i < PPMU_END; i++) { |
| void __iomem *ppmu_base = data->ppmu[i].hw_base; |
| |
| /* Reset the performance and cycle counters */ |
| exynos_ppmu_reset(ppmu_base); |
| |
| /* Setup count registers to monitor read/write transactions */ |
| data->ppmu[i].event[PPMU_PMNCNT3] = RDWR_DATA_COUNT; |
| exynos_ppmu_setevent(ppmu_base, PPMU_PMNCNT3, |
| data->ppmu[i].event[PPMU_PMNCNT3]); |
| |
| exynos_ppmu_start(ppmu_base); |
| } |
| } |
| |
| static void exynos5_read_ppmu(struct busfreq_data_int *data) |
| { |
| int i, j; |
| |
| for (i = PPMU_RIGHT; i < PPMU_END; i++) { |
| void __iomem *ppmu_base = data->ppmu[i].hw_base; |
| |
| exynos_ppmu_stop(ppmu_base); |
| |
| /* Update local data from PPMU */ |
| data->ppmu[i].ccnt = __raw_readl(ppmu_base + PPMU_CCNT); |
| |
| for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) { |
| if (data->ppmu[i].event[j] == 0) |
| data->ppmu[i].count[j] = 0; |
| else |
| data->ppmu[i].count[j] = |
| exynos_ppmu_read(ppmu_base, j); |
| } |
| } |
| |
| busfreq_mon_reset(data); |
| } |
| |
| static int exynos5_int_setvolt(struct busfreq_data_int *data, |
| unsigned long volt) |
| { |
| return regulator_set_voltage(data->vdd_int, volt, MAX_SAFEVOLT); |
| } |
| |
| static int exynos5_busfreq_int_target(struct device *dev, unsigned long *_freq, |
| u32 flags) |
| { |
| int err = 0; |
| struct platform_device *pdev = container_of(dev, struct platform_device, |
| dev); |
| struct busfreq_data_int *data = platform_get_drvdata(pdev); |
| struct dev_pm_opp *opp; |
| unsigned long old_freq, freq; |
| unsigned long volt; |
| |
| rcu_read_lock(); |
| opp = devfreq_recommended_opp(dev, _freq, flags); |
| if (IS_ERR(opp)) { |
| rcu_read_unlock(); |
| dev_err(dev, "%s: Invalid OPP.\n", __func__); |
| return PTR_ERR(opp); |
| } |
| |
| freq = dev_pm_opp_get_freq(opp); |
| volt = dev_pm_opp_get_voltage(opp); |
| rcu_read_unlock(); |
| |
| old_freq = data->curr_freq; |
| |
| if (old_freq == freq) |
| return 0; |
| |
| dev_dbg(dev, "targetting %lukHz %luuV\n", freq, volt); |
| |
| mutex_lock(&data->lock); |
| |
| if (data->disabled) |
| goto out; |
| |
| if (freq > exynos5_int_opp_table[0].clk) |
| pm_qos_update_request(&data->int_req, freq * 16 / 1000); |
| else |
| pm_qos_update_request(&data->int_req, -1); |
| |
| if (old_freq < freq) |
| err = exynos5_int_setvolt(data, volt); |
| if (err) |
| goto out; |
| |
| err = clk_set_rate(data->int_clk, freq * 1000); |
| |
| if (err) |
| goto out; |
| |
| if (old_freq > freq) |
| err = exynos5_int_setvolt(data, volt); |
| if (err) |
| goto out; |
| |
| data->curr_freq = freq; |
| out: |
| mutex_unlock(&data->lock); |
| return err; |
| } |
| |
| static int exynos5_get_busier_dmc(struct busfreq_data_int *data) |
| { |
| int i, j; |
| int busy = 0; |
| unsigned int temp = 0; |
| |
| for (i = PPMU_RIGHT; i < PPMU_END; i++) { |
| for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) { |
| if (data->ppmu[i].count[j] > temp) { |
| temp = data->ppmu[i].count[j]; |
| busy = i; |
| } |
| } |
| } |
| |
| return busy; |
| } |
| |
| static int exynos5_int_get_dev_status(struct device *dev, |
| struct devfreq_dev_status *stat) |
| { |
| struct platform_device *pdev = container_of(dev, struct platform_device, |
| dev); |
| struct busfreq_data_int *data = platform_get_drvdata(pdev); |
| int busier_dmc; |
| |
| exynos5_read_ppmu(data); |
| busier_dmc = exynos5_get_busier_dmc(data); |
| |
| stat->current_frequency = data->curr_freq; |
| |
| /* Number of cycles spent on memory access */ |
| stat->busy_time = data->ppmu[busier_dmc].count[PPMU_PMNCNT3]; |
| stat->busy_time *= 100 / INT_BUS_SATURATION_RATIO; |
| stat->total_time = data->ppmu[busier_dmc].ccnt; |
| |
| return 0; |
| } |
| static void exynos5_int_exit(struct device *dev) |
| { |
| struct platform_device *pdev = container_of(dev, struct platform_device, |
| dev); |
| struct busfreq_data_int *data = platform_get_drvdata(pdev); |
| |
| devfreq_unregister_opp_notifier(dev, data->devfreq); |
| } |
| |
| static struct devfreq_dev_profile exynos5_devfreq_int_profile = { |
| .initial_freq = 160000, |
| .polling_ms = 100, |
| .target = exynos5_busfreq_int_target, |
| .get_dev_status = exynos5_int_get_dev_status, |
| .exit = exynos5_int_exit, |
| }; |
| |
| static int exynos5250_init_int_tables(struct busfreq_data_int *data) |
| { |
| int i, err = 0; |
| |
| for (i = LV_0; i < _LV_END; i++) { |
| err = dev_pm_opp_add(data->dev, exynos5_int_opp_table[i].clk, |
| exynos5_int_opp_table[i].volt); |
| if (err) { |
| dev_err(data->dev, "Cannot add opp entries.\n"); |
| return err; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int exynos5_busfreq_int_pm_notifier_event(struct notifier_block *this, |
| unsigned long event, void *ptr) |
| { |
| struct busfreq_data_int *data = container_of(this, |
| struct busfreq_data_int, pm_notifier); |
| struct dev_pm_opp *opp; |
| unsigned long maxfreq = ULONG_MAX; |
| unsigned long freq; |
| unsigned long volt; |
| int err = 0; |
| |
| switch (event) { |
| case PM_SUSPEND_PREPARE: |
| /* Set Fastest and Deactivate DVFS */ |
| mutex_lock(&data->lock); |
| |
| data->disabled = true; |
| |
| rcu_read_lock(); |
| opp = dev_pm_opp_find_freq_floor(data->dev, &maxfreq); |
| if (IS_ERR(opp)) { |
| rcu_read_unlock(); |
| err = PTR_ERR(opp); |
| goto unlock; |
| } |
| freq = dev_pm_opp_get_freq(opp); |
| volt = dev_pm_opp_get_voltage(opp); |
| rcu_read_unlock(); |
| |
| err = exynos5_int_setvolt(data, volt); |
| if (err) |
| goto unlock; |
| |
| err = clk_set_rate(data->int_clk, freq * 1000); |
| |
| if (err) |
| goto unlock; |
| |
| data->curr_freq = freq; |
| unlock: |
| mutex_unlock(&data->lock); |
| if (err) |
| return NOTIFY_BAD; |
| return NOTIFY_OK; |
| case PM_POST_RESTORE: |
| case PM_POST_SUSPEND: |
| /* Reactivate */ |
| mutex_lock(&data->lock); |
| data->disabled = false; |
| mutex_unlock(&data->lock); |
| return NOTIFY_OK; |
| } |
| |
| return NOTIFY_DONE; |
| } |
| |
| static int exynos5_busfreq_int_probe(struct platform_device *pdev) |
| { |
| struct busfreq_data_int *data; |
| struct dev_pm_opp *opp; |
| struct device *dev = &pdev->dev; |
| struct device_node *np; |
| unsigned long initial_freq; |
| unsigned long initial_volt; |
| int err = 0; |
| int i; |
| |
| data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data_int), |
| GFP_KERNEL); |
| if (data == NULL) { |
| dev_err(dev, "Cannot allocate memory.\n"); |
| return -ENOMEM; |
| } |
| |
| np = of_find_compatible_node(NULL, NULL, "samsung,exynos5250-ppmu"); |
| if (np == NULL) { |
| pr_err("Unable to find PPMU node\n"); |
| return -ENOENT; |
| } |
| |
| for (i = PPMU_RIGHT; i < PPMU_END; i++) { |
| /* map PPMU memory region */ |
| data->ppmu[i].hw_base = of_iomap(np, i); |
| if (data->ppmu[i].hw_base == NULL) { |
| dev_err(&pdev->dev, "failed to map memory region\n"); |
| return -ENOMEM; |
| } |
| } |
| data->pm_notifier.notifier_call = exynos5_busfreq_int_pm_notifier_event; |
| data->dev = dev; |
| mutex_init(&data->lock); |
| |
| err = exynos5250_init_int_tables(data); |
| if (err) |
| return err; |
| |
| data->vdd_int = devm_regulator_get(dev, "vdd_int"); |
| if (IS_ERR(data->vdd_int)) { |
| dev_err(dev, "Cannot get the regulator \"vdd_int\"\n"); |
| return PTR_ERR(data->vdd_int); |
| } |
| |
| data->int_clk = devm_clk_get(dev, "int_clk"); |
| if (IS_ERR(data->int_clk)) { |
| dev_err(dev, "Cannot get clock \"int_clk\"\n"); |
| return PTR_ERR(data->int_clk); |
| } |
| |
| rcu_read_lock(); |
| opp = dev_pm_opp_find_freq_floor(dev, |
| &exynos5_devfreq_int_profile.initial_freq); |
| if (IS_ERR(opp)) { |
| rcu_read_unlock(); |
| dev_err(dev, "Invalid initial frequency %lu kHz.\n", |
| exynos5_devfreq_int_profile.initial_freq); |
| return PTR_ERR(opp); |
| } |
| initial_freq = dev_pm_opp_get_freq(opp); |
| initial_volt = dev_pm_opp_get_voltage(opp); |
| rcu_read_unlock(); |
| data->curr_freq = initial_freq; |
| |
| err = clk_set_rate(data->int_clk, initial_freq * 1000); |
| if (err) { |
| dev_err(dev, "Failed to set initial frequency\n"); |
| return err; |
| } |
| |
| err = exynos5_int_setvolt(data, initial_volt); |
| if (err) |
| return err; |
| |
| platform_set_drvdata(pdev, data); |
| |
| busfreq_mon_reset(data); |
| |
| data->devfreq = devfreq_add_device(dev, &exynos5_devfreq_int_profile, |
| "simple_ondemand", NULL); |
| |
| if (IS_ERR(data->devfreq)) { |
| err = PTR_ERR(data->devfreq); |
| goto err_devfreq_add; |
| } |
| |
| devfreq_register_opp_notifier(dev, data->devfreq); |
| |
| err = register_pm_notifier(&data->pm_notifier); |
| if (err) { |
| dev_err(dev, "Failed to setup pm notifier\n"); |
| goto err_devfreq_add; |
| } |
| |
| /* TODO: Add a new QOS class for int/mif bus */ |
| pm_qos_add_request(&data->int_req, PM_QOS_NETWORK_THROUGHPUT, -1); |
| |
| return 0; |
| |
| err_devfreq_add: |
| devfreq_remove_device(data->devfreq); |
| return err; |
| } |
| |
| static int exynos5_busfreq_int_remove(struct platform_device *pdev) |
| { |
| struct busfreq_data_int *data = platform_get_drvdata(pdev); |
| |
| pm_qos_remove_request(&data->int_req); |
| unregister_pm_notifier(&data->pm_notifier); |
| devfreq_remove_device(data->devfreq); |
| |
| return 0; |
| } |
| |
| static int exynos5_busfreq_int_resume(struct device *dev) |
| { |
| struct platform_device *pdev = container_of(dev, struct platform_device, |
| dev); |
| struct busfreq_data_int *data = platform_get_drvdata(pdev); |
| |
| busfreq_mon_reset(data); |
| return 0; |
| } |
| |
| static const struct dev_pm_ops exynos5_busfreq_int_pm = { |
| .resume = exynos5_busfreq_int_resume, |
| }; |
| |
| /* platform device pointer for exynos5 devfreq device. */ |
| static struct platform_device *exynos5_devfreq_pdev; |
| |
| static struct platform_driver exynos5_busfreq_int_driver = { |
| .probe = exynos5_busfreq_int_probe, |
| .remove = exynos5_busfreq_int_remove, |
| .driver = { |
| .name = "exynos5-bus-int", |
| .owner = THIS_MODULE, |
| .pm = &exynos5_busfreq_int_pm, |
| }, |
| }; |
| |
| static int __init exynos5_busfreq_int_init(void) |
| { |
| int ret; |
| |
| ret = platform_driver_register(&exynos5_busfreq_int_driver); |
| if (ret < 0) |
| goto out; |
| |
| exynos5_devfreq_pdev = |
| platform_device_register_simple("exynos5-bus-int", -1, NULL, 0); |
| if (IS_ERR(exynos5_devfreq_pdev)) { |
| ret = PTR_ERR(exynos5_devfreq_pdev); |
| goto out1; |
| } |
| |
| return 0; |
| out1: |
| platform_driver_unregister(&exynos5_busfreq_int_driver); |
| out: |
| return ret; |
| } |
| late_initcall(exynos5_busfreq_int_init); |
| |
| static void __exit exynos5_busfreq_int_exit(void) |
| { |
| platform_device_unregister(exynos5_devfreq_pdev); |
| platform_driver_unregister(&exynos5_busfreq_int_driver); |
| } |
| module_exit(exynos5_busfreq_int_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("EXYNOS5 busfreq driver with devfreq framework"); |