diff options
| -rw-r--r-- | drivers/devfreq/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/devfreq/exynos-bus.c | 219 |
2 files changed, 174 insertions, 46 deletions
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig index d260cd0219f6..30e1daf1c827 100644 --- a/drivers/devfreq/Kconfig +++ b/drivers/devfreq/Kconfig @@ -78,6 +78,7 @@ config ARM_EXYNOS_BUS_DEVFREQ bool "ARM EXYNOS Generic Memory Bus DEVFREQ Driver" depends on ARCH_EXYNOS select DEVFREQ_GOV_SIMPLE_ONDEMAND + select DEVFREQ_GOV_PASSIVE select DEVFREQ_EVENT_EXYNOS_PPMU select PM_DEVFREQ_EVENT select PM_OPP diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c index 137de6196af3..50fe1a16c574 100644 --- a/drivers/devfreq/exynos-bus.c +++ b/drivers/devfreq/exynos-bus.c @@ -1,7 +1,7 @@ /* * Generic Exynos Bus frequency driver with DEVFREQ Framework * - * Copyright (c) 2015 Samsung Electronics Co., Ltd. + * Copyright (c) 2016 Samsung Electronics Co., Ltd. * Author : Chanwoo Choi <cw00.choi@samsung.com> * * This driver support Exynos Bus frequency feature by using @@ -93,7 +93,7 @@ static int exynos_bus_get_event(struct exynos_bus *bus, } /* - * Must necessary function for devfreq governor + * Must necessary function for devfreq simple-ondemand governor */ static int exynos_bus_target(struct device *dev, unsigned long *freq, u32 flags) { @@ -202,59 +202,81 @@ static void exynos_bus_exit(struct device *dev) regulator_disable(bus->regulator); dev_pm_opp_of_remove_table(dev); + clk_disable_unprepare(bus->clk); } -static int exynos_bus_parse_of(struct device_node *np, - struct exynos_bus *bus) +/* + * Must necessary function for devfreq passive governor + */ +static int exynos_bus_passive_target(struct device *dev, unsigned long *freq, + u32 flags) { - struct device *dev = bus->dev; - unsigned long rate; - int i, ret, count, size; + struct exynos_bus *bus = dev_get_drvdata(dev); + struct dev_pm_opp *new_opp; + unsigned long old_freq, new_freq; + int ret = 0; - /* Get the clock to provide each bus with source clock */ - bus->clk = devm_clk_get(dev, "bus"); - if (IS_ERR(bus->clk)) { - dev_err(dev, "failed to get bus clock\n"); - return PTR_ERR(bus->clk); + /* Get new opp-bus instance according to new bus clock */ + rcu_read_lock(); + new_opp = devfreq_recommended_opp(dev, freq, flags); + if (IS_ERR(new_opp)) { + dev_err(dev, "failed to get recommended opp instance\n"); + rcu_read_unlock(); + return PTR_ERR(new_opp); } - ret = clk_prepare_enable(bus->clk); - if (ret < 0) { - dev_err(dev, "failed to get enable clock\n"); - return ret; - } + new_freq = dev_pm_opp_get_freq(new_opp); + old_freq = dev_pm_opp_get_freq(bus->curr_opp); + rcu_read_unlock(); - /* Get the freq/voltage OPP table to scale the bus frequency */ - rcu_read_lock(); - ret = dev_pm_opp_of_add_table(dev); + if (old_freq == new_freq) + return 0; + + /* Change the frequency according to new OPP level */ + mutex_lock(&bus->lock); + + ret = clk_set_rate(bus->clk, new_freq); if (ret < 0) { - dev_err(dev, "failed to get OPP table\n"); - rcu_read_unlock(); - goto err_clk; + dev_err(dev, "failed to set the clock of bus\n"); + goto out; } - rate = clk_get_rate(bus->clk); - bus->curr_opp = dev_pm_opp_find_freq_ceil(dev, &rate); - if (IS_ERR(bus->curr_opp)) { - dev_err(dev, "failed to find dev_pm_opp\n"); - rcu_read_unlock(); - ret = PTR_ERR(bus->curr_opp); - goto err_opp; - } - rcu_read_unlock(); + *freq = new_freq; + bus->curr_opp = new_opp; + + dev_dbg(dev, "Set the frequency of bus (%lukHz -> %lukHz)\n", + old_freq/1000, new_freq/1000); +out: + mutex_unlock(&bus->lock); + + return ret; +} + +static void exynos_bus_passive_exit(struct device *dev) +{ + struct exynos_bus *bus = dev_get_drvdata(dev); + + dev_pm_opp_of_remove_table(dev); + clk_disable_unprepare(bus->clk); +} + +static int exynos_bus_parent_parse_of(struct device_node *np, + struct exynos_bus *bus) +{ + struct device *dev = bus->dev; + int i, ret, count, size; /* Get the regulator to provide each bus with the power */ bus->regulator = devm_regulator_get(dev, "vdd"); if (IS_ERR(bus->regulator)) { dev_err(dev, "failed to get VDD regulator\n"); - ret = PTR_ERR(bus->regulator); - goto err_opp; + return PTR_ERR(bus->regulator); } ret = regulator_enable(bus->regulator); if (ret < 0) { dev_err(dev, "failed to enable VDD regulator\n"); - goto err_opp; + return ret; } /* @@ -305,6 +327,51 @@ static int exynos_bus_parse_of(struct device_node *np, err_regulator: regulator_disable(bus->regulator); + + return ret; +} + +static int exynos_bus_parse_of(struct device_node *np, + struct exynos_bus *bus) +{ + struct device *dev = bus->dev; + unsigned long rate; + int ret; + + /* Get the clock to provide each bus with source clock */ + bus->clk = devm_clk_get(dev, "bus"); + if (IS_ERR(bus->clk)) { + dev_err(dev, "failed to get bus clock\n"); + return PTR_ERR(bus->clk); + } + + ret = clk_prepare_enable(bus->clk); + if (ret < 0) { + dev_err(dev, "failed to get enable clock\n"); + return ret; + } + + /* Get the freq and voltage from OPP table to scale the bus freq */ + rcu_read_lock(); + ret = dev_pm_opp_of_add_table(dev); + if (ret < 0) { + dev_err(dev, "failed to get OPP table\n"); + rcu_read_unlock(); + goto err_clk; + } + + rate = clk_get_rate(bus->clk); + bus->curr_opp = devfreq_recommended_opp(dev, &rate, 0); + if (IS_ERR(bus->curr_opp)) { + dev_err(dev, "failed to find dev_pm_opp\n"); + rcu_read_unlock(); + ret = PTR_ERR(bus->curr_opp); + goto err_opp; + } + rcu_read_unlock(); + + return 0; + err_opp: dev_pm_opp_of_remove_table(dev); err_clk: @@ -319,8 +386,11 @@ static int exynos_bus_probe(struct platform_device *pdev) struct device_node *np = dev->of_node; struct devfreq_dev_profile *profile; struct devfreq_simple_ondemand_data *ondemand_data; + struct devfreq_passive_data *passive_data; + struct devfreq *parent_devfreq; struct exynos_bus *bus; - int ret; + int ret, max_state; + unsigned long min_freq, max_freq; if (!np) { dev_err(dev, "failed to find devicetree node\n"); @@ -337,20 +407,33 @@ static int exynos_bus_probe(struct platform_device *pdev) /* Parse the device-tree to get the resource information */ ret = exynos_bus_parse_of(np, bus); if (ret < 0) - return ret; + goto err; - /* Initalize the struct profile and governor data */ profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL); - if (!profile) - return -ENOMEM; + if (!profile) { + ret = -ENOMEM; + goto err; + } + + if (of_parse_phandle(dev->of_node, "devfreq", 0)) + goto passive; + else + ret = exynos_bus_parent_parse_of(np, bus); + + if (ret < 0) + goto err; + + /* Initalize the struct profile and governor data for parent device */ profile->polling_ms = 50; profile->target = exynos_bus_target; profile->get_dev_status = exynos_bus_get_dev_status; profile->exit = exynos_bus_exit; ondemand_data = devm_kzalloc(dev, sizeof(*ondemand_data), GFP_KERNEL); - if (!ondemand_data) - return -ENOMEM; + if (!ondemand_data) { + ret = -ENOMEM; + goto err; + } ondemand_data->upthreshold = 40; ondemand_data->downdifferential = 5; @@ -359,14 +442,15 @@ static int exynos_bus_probe(struct platform_device *pdev) ondemand_data); if (IS_ERR(bus->devfreq)) { dev_err(dev, "failed to add devfreq device\n"); - return PTR_ERR(bus->devfreq); + ret = PTR_ERR(bus->devfreq); + goto err; } /* Register opp_notifier to catch the change of OPP */ ret = devm_devfreq_register_opp_notifier(dev, bus->devfreq); if (ret < 0) { dev_err(dev, "failed to register opp notifier\n"); - return ret; + goto err; } /* @@ -376,16 +460,59 @@ static int exynos_bus_probe(struct platform_device *pdev) ret = exynos_bus_enable_edev(bus); if (ret < 0) { dev_err(dev, "failed to enable devfreq-event devices\n"); - return ret; + goto err; } ret = exynos_bus_set_event(bus); if (ret < 0) { dev_err(dev, "failed to set event to devfreq-event devices\n"); - return ret; + goto err; } + goto out; +passive: + /* Initalize the struct profile and governor data for passive device */ + profile->target = exynos_bus_passive_target; + profile->exit = exynos_bus_passive_exit; + + /* Get the instance of parent devfreq device */ + parent_devfreq = devfreq_get_devfreq_by_phandle(dev, 0); + if (IS_ERR(parent_devfreq)) { + ret = -EPROBE_DEFER; + goto err; + } + + passive_data = devm_kzalloc(dev, sizeof(*passive_data), GFP_KERNEL); + if (!passive_data) { + ret = -ENOMEM; + goto err; + } + passive_data->parent = parent_devfreq; + + /* Add devfreq device for exynos bus with passive governor */ + bus->devfreq = devm_devfreq_add_device(dev, profile, "passive", + passive_data); + if (IS_ERR(bus->devfreq)) { + dev_err(dev, + "failed to add devfreq dev with passive governor\n"); + ret = -EPROBE_DEFER; + goto err; + } + +out: + max_state = bus->devfreq->profile->max_state; + min_freq = (bus->devfreq->profile->freq_table[0] / 1000); + max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000); + pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n", + dev_name(dev), min_freq, max_freq); + return 0; + +err: + dev_pm_opp_of_remove_table(dev); + clk_disable_unprepare(bus->clk); + + return ret; } #ifdef CONFIG_PM_SLEEP |