From: Mike Turquette <[email protected]> Removes directly handling of OPP tables and voltage regulators by calling of_clk_cpufreq_notifier_handler, introduced by commit "clk: cpufreq helper for voltage scaling".
In the future this can help consolidate code found across similar CPUfreq drivers. [[email protected]: updates to keep the OPP logic still in cpufreq-cpu0 - optimization to generalize that for cpufreq is to be done in a later series] Signed-off-by: Nishanth Menon <[email protected]> Signed-off-by: Mike Turquette <[email protected]> --- drivers/cpufreq/Kconfig | 1 + drivers/cpufreq/cpufreq-cpu0.c | 140 ++++++++++++---------------------------- 2 files changed, 42 insertions(+), 99 deletions(-) diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig index 4b029c0..70b07ab 100644 --- a/drivers/cpufreq/Kconfig +++ b/drivers/cpufreq/Kconfig @@ -187,6 +187,7 @@ config GENERIC_CPUFREQ_CPU0 tristate "Generic CPU0 cpufreq driver" depends on HAVE_CLK && REGULATOR && OF && THERMAL && CPU_THERMAL select PM_OPP + select VOLTAGE_DOMAIN help This adds a generic cpufreq driver for CPU0 frequency management. It supports both uniprocessor (UP) and symmetric multiprocessor (SMP) diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c index 0c12ffc..32719d3 100644 --- a/drivers/cpufreq/cpufreq-cpu0.c +++ b/drivers/cpufreq/cpufreq-cpu0.c @@ -21,23 +21,20 @@ #include <linux/of.h> #include <linux/pm_opp.h> #include <linux/platform_device.h> -#include <linux/regulator/consumer.h> +#include <linux/pm_voltage_domain.h> #include <linux/slab.h> #include <linux/thermal.h> static unsigned int transition_latency; -static unsigned int voltage_tolerance; /* in percentage */ static struct device *cpu_dev; static struct clk *cpu_clk; -static struct regulator *cpu_reg; static struct cpufreq_frequency_table *freq_table; static struct thermal_cooling_device *cdev; +static struct notifier_block *clk_nb; static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index) { - struct dev_pm_opp *opp; - unsigned long volt = 0, volt_old = 0, tol = 0; unsigned int old_freq, new_freq; long freq_Hz, freq_exact; int ret; @@ -50,50 +47,14 @@ static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index) new_freq = freq_Hz / 1000; old_freq = clk_get_rate(cpu_clk) / 1000; - if (!IS_ERR(cpu_reg)) { - rcu_read_lock(); - opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_Hz); - if (IS_ERR(opp)) { - rcu_read_unlock(); - pr_err("failed to find OPP for %ld\n", freq_Hz); - return PTR_ERR(opp); - } - volt = dev_pm_opp_get_voltage(opp); - rcu_read_unlock(); - tol = volt * voltage_tolerance / 100; - volt_old = regulator_get_voltage(cpu_reg); - } - - pr_debug("%u MHz, %ld mV --> %u MHz, %ld mV\n", - old_freq / 1000, volt_old ? volt_old / 1000 : -1, - new_freq / 1000, volt ? volt / 1000 : -1); - - /* scaling up? scale voltage before frequency */ - if (!IS_ERR(cpu_reg) && new_freq > old_freq) { - ret = regulator_set_voltage_tol(cpu_reg, volt, tol); - if (ret) { - pr_err("failed to scale voltage up: %d\n", ret); - return ret; - } - } + pr_debug("%u MHz --> %u MHz\n", old_freq / 1000, new_freq / 1000); ret = clk_set_rate(cpu_clk, freq_exact); if (ret) { pr_err("failed to set clock rate: %d\n", ret); - if (!IS_ERR(cpu_reg)) - regulator_set_voltage_tol(cpu_reg, volt_old, tol); return ret; } - /* scaling down? scale voltage after frequency */ - if (!IS_ERR(cpu_reg) && new_freq < old_freq) { - ret = regulator_set_voltage_tol(cpu_reg, volt, tol); - if (ret) { - pr_err("failed to scale voltage down: %d\n", ret); - clk_set_rate(cpu_clk, old_freq * 1000); - } - } - return ret; } @@ -117,33 +78,24 @@ static struct cpufreq_driver cpu0_cpufreq_driver = { static int cpu0_cpufreq_probe(struct platform_device *pdev) { struct device_node *np; + unsigned int voltage_latency; int ret; - cpu_dev = get_cpu_device(0); if (!cpu_dev) { - pr_err("failed to get cpu0 device\n"); - return -ENODEV; - } - - np = of_node_get(cpu_dev->of_node); - if (!np) { - pr_err("failed to find cpu0 node\n"); - return -ENOENT; - } + cpu_dev = get_cpu_device(0); + if (!cpu_dev) { + pr_err("failed to get cpu0 device\n"); + return -ENODEV; + } - cpu_reg = devm_regulator_get_optional(cpu_dev, "cpu0"); - if (IS_ERR(cpu_reg)) { - /* - * If cpu0 regulator supply node is present, but regulator is - * not yet registered, we should try defering probe. - */ - if (PTR_ERR(cpu_reg) == -EPROBE_DEFER) { - dev_err(cpu_dev, "cpu0 regulator not ready, retry\n"); - ret = -EPROBE_DEFER; - goto out_put_node; + np = of_node_get(cpu_dev->of_node); + ret = of_init_opp_table(cpu_dev); + if (ret) { + pr_err("failed to init OPP table: %d\n", ret); + return ret; } - pr_warn("failed to get cpu0 regulator: %ld\n", - PTR_ERR(cpu_reg)); + } else { + np = of_node_get(cpu_dev->of_node); } cpu_clk = devm_clk_get(cpu_dev, NULL); @@ -153,11 +105,8 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev) goto out_put_node; } - ret = of_init_opp_table(cpu_dev); - if (ret) { - pr_err("failed to init OPP table: %d\n", ret); - goto out_put_node; - } + if (of_property_read_u32(np, "clock-latency", &transition_latency)) + transition_latency = CPUFREQ_ETERNAL; ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table); if (ret) { @@ -165,40 +114,30 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev) goto out_put_node; } - of_property_read_u32(np, "voltage-tolerance", &voltage_tolerance); - - if (of_property_read_u32(np, "clock-latency", &transition_latency)) - transition_latency = CPUFREQ_ETERNAL; - - if (!IS_ERR(cpu_reg)) { - struct dev_pm_opp *opp; - unsigned long min_uV, max_uV; - int i; - - /* - * OPP is maintained in order of increasing frequency, and - * freq_table initialised from OPP is therefore sorted in the - * same order. - */ - for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++) - ; - rcu_read_lock(); - opp = dev_pm_opp_find_freq_exact(cpu_dev, - freq_table[0].frequency * 1000, true); - min_uV = dev_pm_opp_get_voltage(opp); - opp = dev_pm_opp_find_freq_exact(cpu_dev, - freq_table[i-1].frequency * 1000, true); - max_uV = dev_pm_opp_get_voltage(opp); - rcu_read_unlock(); - ret = regulator_set_voltage_time(cpu_reg, min_uV, max_uV); - if (ret > 0) - transition_latency += ret * 1000; + clk_nb = of_pm_voltdm_notifier_register(cpu_dev, np, cpu_clk, "cpu0", + &voltage_latency); + + if (IS_ERR(clk_nb)) { + ret = PTR_ERR(clk_nb); + /* defer probe if regulator is not yet registered */ + if (ret == -EPROBE_DEFER) { + dev_err(cpu_dev, + "cpu0 clock notifier not ready, retry\n"); + } else { + dev_err(cpu_dev, + "Failed to register cpu0 clock notifier: %d\n", + ret); + } + goto out_freq_table_free; } + if (voltage_latency > 0) + transition_latency += voltage_latency; + ret = cpufreq_register_driver(&cpu0_cpufreq_driver); if (ret) { pr_err("failed register driver: %d\n", ret); - goto out_free_table; + goto out_notifier_unregister; } /* @@ -215,7 +154,9 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev) of_node_put(np); return 0; -out_free_table: +out_notifier_unregister: + of_pm_voltdm_notifier_unregister(clk_nb); +out_freq_table_free: dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); out_put_node: of_node_put(np); @@ -226,6 +167,7 @@ static int cpu0_cpufreq_remove(struct platform_device *pdev) { cpufreq_cooling_unregister(cdev); cpufreq_unregister_driver(&cpu0_cpufreq_driver); + of_pm_voltdm_notifier_unregister(clk_nb); dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); return 0; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
