| /* |
| * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. |
| * http://www.samsung.com |
| * |
| * EXYNOS - CPU frequency scaling support for EXYNOS series |
| * |
| * 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/kernel.h> |
| #include <linux/module.h> |
| #include <linux/err.h> |
| #include <linux/clk.h> |
| #include <linux/io.h> |
| #include <linux/slab.h> |
| #include <linux/regulator/consumer.h> |
| #include <linux/cpufreq.h> |
| #include <linux/platform_device.h> |
| #include <linux/of.h> |
| #include <linux/cpu_cooling.h> |
| #include <linux/cpu.h> |
| |
| #include "exynos-cpufreq.h" |
| |
| static struct exynos_dvfs_info *exynos_info; |
| static struct thermal_cooling_device *cdev; |
| static struct regulator *arm_regulator; |
| static unsigned int locking_frequency; |
| |
| static int exynos_cpufreq_get_index(unsigned int freq) |
| { |
| struct cpufreq_frequency_table *freq_table = exynos_info->freq_table; |
| struct cpufreq_frequency_table *pos; |
| |
| cpufreq_for_each_entry(pos, freq_table) |
| if (pos->frequency == freq) |
| break; |
| |
| if (pos->frequency == CPUFREQ_TABLE_END) |
| return -EINVAL; |
| |
| return pos - freq_table; |
| } |
| |
| static int exynos_cpufreq_scale(unsigned int target_freq) |
| { |
| struct cpufreq_frequency_table *freq_table = exynos_info->freq_table; |
| unsigned int *volt_table = exynos_info->volt_table; |
| struct cpufreq_policy *policy = cpufreq_cpu_get(0); |
| unsigned int arm_volt, safe_arm_volt = 0; |
| unsigned int mpll_freq_khz = exynos_info->mpll_freq_khz; |
| struct device *dev = exynos_info->dev; |
| unsigned int old_freq; |
| int index, old_index; |
| int ret = 0; |
| |
| old_freq = policy->cur; |
| |
| /* |
| * The policy max have been changed so that we cannot get proper |
| * old_index with cpufreq_frequency_table_target(). Thus, ignore |
| * policy and get the index from the raw frequency table. |
| */ |
| old_index = exynos_cpufreq_get_index(old_freq); |
| if (old_index < 0) { |
| ret = old_index; |
| goto out; |
| } |
| |
| index = exynos_cpufreq_get_index(target_freq); |
| if (index < 0) { |
| ret = index; |
| goto out; |
| } |
| |
| /* |
| * ARM clock source will be changed APLL to MPLL temporary |
| * To support this level, need to control regulator for |
| * required voltage level |
| */ |
| if (exynos_info->need_apll_change != NULL) { |
| if (exynos_info->need_apll_change(old_index, index) && |
| (freq_table[index].frequency < mpll_freq_khz) && |
| (freq_table[old_index].frequency < mpll_freq_khz)) |
| safe_arm_volt = volt_table[exynos_info->pll_safe_idx]; |
| } |
| arm_volt = volt_table[index]; |
| |
| /* When the new frequency is higher than current frequency */ |
| if ((target_freq > old_freq) && !safe_arm_volt) { |
| /* Firstly, voltage up to increase frequency */ |
| ret = regulator_set_voltage(arm_regulator, arm_volt, arm_volt); |
| if (ret) { |
| dev_err(dev, "failed to set cpu voltage to %d\n", |
| arm_volt); |
| return ret; |
| } |
| } |
| |
| if (safe_arm_volt) { |
| ret = regulator_set_voltage(arm_regulator, safe_arm_volt, |
| safe_arm_volt); |
| if (ret) { |
| dev_err(dev, "failed to set cpu voltage to %d\n", |
| safe_arm_volt); |
| return ret; |
| } |
| } |
| |
| exynos_info->set_freq(old_index, index); |
| |
| /* When the new frequency is lower than current frequency */ |
| if ((target_freq < old_freq) || |
| ((target_freq > old_freq) && safe_arm_volt)) { |
| /* down the voltage after frequency change */ |
| ret = regulator_set_voltage(arm_regulator, arm_volt, |
| arm_volt); |
| if (ret) { |
| dev_err(dev, "failed to set cpu voltage to %d\n", |
| arm_volt); |
| goto out; |
| } |
| } |
| |
| out: |
| cpufreq_cpu_put(policy); |
| |
| return ret; |
| } |
| |
| static int exynos_target(struct cpufreq_policy *policy, unsigned int index) |
| { |
| return exynos_cpufreq_scale(exynos_info->freq_table[index].frequency); |
| } |
| |
| static int exynos_cpufreq_cpu_init(struct cpufreq_policy *policy) |
| { |
| policy->clk = exynos_info->cpu_clk; |
| policy->suspend_freq = locking_frequency; |
| return cpufreq_generic_init(policy, exynos_info->freq_table, 100000); |
| } |
| |
| static struct cpufreq_driver exynos_driver = { |
| .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, |
| .verify = cpufreq_generic_frequency_table_verify, |
| .target_index = exynos_target, |
| .get = cpufreq_generic_get, |
| .init = exynos_cpufreq_cpu_init, |
| .name = "exynos_cpufreq", |
| .attr = cpufreq_generic_attr, |
| #ifdef CONFIG_ARM_EXYNOS_CPU_FREQ_BOOST_SW |
| .boost_supported = true, |
| #endif |
| #ifdef CONFIG_PM |
| .suspend = cpufreq_generic_suspend, |
| #endif |
| }; |
| |
| static int exynos_cpufreq_probe(struct platform_device *pdev) |
| { |
| struct device_node *cpu0; |
| int ret = -EINVAL; |
| |
| exynos_info = kzalloc(sizeof(*exynos_info), GFP_KERNEL); |
| if (!exynos_info) |
| return -ENOMEM; |
| |
| exynos_info->dev = &pdev->dev; |
| |
| if (of_machine_is_compatible("samsung,exynos4212")) { |
| exynos_info->type = EXYNOS_SOC_4212; |
| ret = exynos4x12_cpufreq_init(exynos_info); |
| } else if (of_machine_is_compatible("samsung,exynos4412")) { |
| exynos_info->type = EXYNOS_SOC_4412; |
| ret = exynos4x12_cpufreq_init(exynos_info); |
| } else if (of_machine_is_compatible("samsung,exynos5250")) { |
| exynos_info->type = EXYNOS_SOC_5250; |
| ret = exynos5250_cpufreq_init(exynos_info); |
| } else { |
| pr_err("%s: Unknown SoC type\n", __func__); |
| ret = -ENODEV; |
| } |
| |
| if (ret) |
| goto err_vdd_arm; |
| |
| if (exynos_info->set_freq == NULL) { |
| dev_err(&pdev->dev, "No set_freq function (ERR)\n"); |
| ret = -EINVAL; |
| goto err_vdd_arm; |
| } |
| |
| arm_regulator = regulator_get(NULL, "vdd_arm"); |
| if (IS_ERR(arm_regulator)) { |
| dev_err(&pdev->dev, "failed to get resource vdd_arm\n"); |
| ret = -EINVAL; |
| goto err_vdd_arm; |
| } |
| |
| /* Done here as we want to capture boot frequency */ |
| locking_frequency = clk_get_rate(exynos_info->cpu_clk) / 1000; |
| |
| ret = cpufreq_register_driver(&exynos_driver); |
| if (ret) |
| goto err_cpufreq_reg; |
| |
| cpu0 = of_get_cpu_node(0, NULL); |
| if (!cpu0) { |
| pr_err("failed to find cpu0 node\n"); |
| return 0; |
| } |
| |
| if (of_find_property(cpu0, "#cooling-cells", NULL)) { |
| cdev = of_cpufreq_cooling_register(cpu0, |
| cpu_present_mask); |
| if (IS_ERR(cdev)) |
| pr_err("running cpufreq without cooling device: %ld\n", |
| PTR_ERR(cdev)); |
| } |
| |
| return 0; |
| |
| err_cpufreq_reg: |
| dev_err(&pdev->dev, "failed to register cpufreq driver\n"); |
| regulator_put(arm_regulator); |
| err_vdd_arm: |
| kfree(exynos_info); |
| return ret; |
| } |
| |
| static struct platform_driver exynos_cpufreq_platdrv = { |
| .driver = { |
| .name = "exynos-cpufreq", |
| }, |
| .probe = exynos_cpufreq_probe, |
| }; |
| module_platform_driver(exynos_cpufreq_platdrv); |