diff options
Diffstat (limited to 'arch/arm/mach-tegra/cpu-tegra.c')
-rw-r--r-- | arch/arm/mach-tegra/cpu-tegra.c | 294 |
1 files changed, 0 insertions, 294 deletions
diff --git a/arch/arm/mach-tegra/cpu-tegra.c b/arch/arm/mach-tegra/cpu-tegra.c deleted file mode 100644 index 11ca730970f8..000000000000 --- a/arch/arm/mach-tegra/cpu-tegra.c +++ /dev/null @@ -1,294 +0,0 @@ -/* - * arch/arm/mach-tegra/cpu-tegra.c - * - * Copyright (C) 2010 Google, Inc. - * - * Author: - * Colin Cross <ccross@google.com> - * Based on arch/arm/plat-omap/cpu-omap.c, (C) 2005 Nokia Corporation - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/types.h> -#include <linux/sched.h> -#include <linux/cpufreq.h> -#include <linux/delay.h> -#include <linux/init.h> -#include <linux/err.h> -#include <linux/clk.h> -#include <linux/io.h> -#include <linux/suspend.h> - -/* Frequency table index must be sequential starting at 0 */ -static struct cpufreq_frequency_table freq_table[] = { - { 0, 216000 }, - { 1, 312000 }, - { 2, 456000 }, - { 3, 608000 }, - { 4, 760000 }, - { 5, 816000 }, - { 6, 912000 }, - { 7, 1000000 }, - { 8, CPUFREQ_TABLE_END }, -}; - -#define NUM_CPUS 2 - -static struct clk *cpu_clk; -static struct clk *pll_x_clk; -static struct clk *pll_p_clk; -static struct clk *emc_clk; - -static unsigned long target_cpu_speed[NUM_CPUS]; -static DEFINE_MUTEX(tegra_cpu_lock); -static bool is_suspended; - -static int tegra_verify_speed(struct cpufreq_policy *policy) -{ - return cpufreq_frequency_table_verify(policy, freq_table); -} - -static unsigned int tegra_getspeed(unsigned int cpu) -{ - unsigned long rate; - - if (cpu >= NUM_CPUS) - return 0; - - rate = clk_get_rate(cpu_clk) / 1000; - return rate; -} - -static int tegra_cpu_clk_set_rate(unsigned long rate) -{ - int ret; - - /* - * Take an extra reference to the main pll so it doesn't turn - * off when we move the cpu off of it - */ - clk_prepare_enable(pll_x_clk); - - ret = clk_set_parent(cpu_clk, pll_p_clk); - if (ret) { - pr_err("Failed to switch cpu to clock pll_p\n"); - goto out; - } - - if (rate == clk_get_rate(pll_p_clk)) - goto out; - - ret = clk_set_rate(pll_x_clk, rate); - if (ret) { - pr_err("Failed to change pll_x to %lu\n", rate); - goto out; - } - - ret = clk_set_parent(cpu_clk, pll_x_clk); - if (ret) { - pr_err("Failed to switch cpu to clock pll_x\n"); - goto out; - } - -out: - clk_disable_unprepare(pll_x_clk); - return ret; -} - -static int tegra_update_cpu_speed(struct cpufreq_policy *policy, - unsigned long rate) -{ - int ret = 0; - struct cpufreq_freqs freqs; - - freqs.old = tegra_getspeed(0); - freqs.new = rate; - - if (freqs.old == freqs.new) - return ret; - - /* - * Vote on memory bus frequency based on cpu frequency - * This sets the minimum frequency, display or avp may request higher - */ - if (rate >= 816000) - clk_set_rate(emc_clk, 600000000); /* cpu 816 MHz, emc max */ - else if (rate >= 456000) - clk_set_rate(emc_clk, 300000000); /* cpu 456 MHz, emc 150Mhz */ - else - clk_set_rate(emc_clk, 100000000); /* emc 50Mhz */ - - cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); - -#ifdef CONFIG_CPU_FREQ_DEBUG - printk(KERN_DEBUG "cpufreq-tegra: transition: %u --> %u\n", - freqs.old, freqs.new); -#endif - - ret = tegra_cpu_clk_set_rate(freqs.new * 1000); - if (ret) { - pr_err("cpu-tegra: Failed to set cpu frequency to %d kHz\n", - freqs.new); - return ret; - } - - cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); - - return 0; -} - -static unsigned long tegra_cpu_highest_speed(void) -{ - unsigned long rate = 0; - int i; - - for_each_online_cpu(i) - rate = max(rate, target_cpu_speed[i]); - return rate; -} - -static int tegra_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation) -{ - unsigned int idx; - unsigned int freq; - int ret = 0; - - mutex_lock(&tegra_cpu_lock); - - if (is_suspended) { - ret = -EBUSY; - goto out; - } - - cpufreq_frequency_table_target(policy, freq_table, target_freq, - relation, &idx); - - freq = freq_table[idx].frequency; - - target_cpu_speed[policy->cpu] = freq; - - ret = tegra_update_cpu_speed(policy, tegra_cpu_highest_speed()); - -out: - mutex_unlock(&tegra_cpu_lock); - return ret; -} - -static int tegra_pm_notify(struct notifier_block *nb, unsigned long event, - void *dummy) -{ - mutex_lock(&tegra_cpu_lock); - if (event == PM_SUSPEND_PREPARE) { - struct cpufreq_policy *policy = cpufreq_cpu_get(0); - is_suspended = true; - pr_info("Tegra cpufreq suspend: setting frequency to %d kHz\n", - freq_table[0].frequency); - tegra_update_cpu_speed(policy, freq_table[0].frequency); - cpufreq_cpu_put(policy); - } else if (event == PM_POST_SUSPEND) { - is_suspended = false; - } - mutex_unlock(&tegra_cpu_lock); - - return NOTIFY_OK; -} - -static struct notifier_block tegra_cpu_pm_notifier = { - .notifier_call = tegra_pm_notify, -}; - -static int tegra_cpu_init(struct cpufreq_policy *policy) -{ - if (policy->cpu >= NUM_CPUS) - return -EINVAL; - - clk_prepare_enable(emc_clk); - clk_prepare_enable(cpu_clk); - - cpufreq_frequency_table_cpuinfo(policy, freq_table); - cpufreq_frequency_table_get_attr(freq_table, policy->cpu); - policy->cur = tegra_getspeed(policy->cpu); - target_cpu_speed[policy->cpu] = policy->cur; - - /* FIXME: what's the actual transition time? */ - policy->cpuinfo.transition_latency = 300 * 1000; - - cpumask_copy(policy->cpus, cpu_possible_mask); - - if (policy->cpu == 0) - register_pm_notifier(&tegra_cpu_pm_notifier); - - return 0; -} - -static int tegra_cpu_exit(struct cpufreq_policy *policy) -{ - cpufreq_frequency_table_cpuinfo(policy, freq_table); - clk_disable_unprepare(emc_clk); - return 0; -} - -static struct freq_attr *tegra_cpufreq_attr[] = { - &cpufreq_freq_attr_scaling_available_freqs, - NULL, -}; - -static struct cpufreq_driver tegra_cpufreq_driver = { - .verify = tegra_verify_speed, - .target = tegra_target, - .get = tegra_getspeed, - .init = tegra_cpu_init, - .exit = tegra_cpu_exit, - .name = "tegra", - .attr = tegra_cpufreq_attr, -}; - -static int __init tegra_cpufreq_init(void) -{ - cpu_clk = clk_get_sys(NULL, "cpu"); - if (IS_ERR(cpu_clk)) - return PTR_ERR(cpu_clk); - - pll_x_clk = clk_get_sys(NULL, "pll_x"); - if (IS_ERR(pll_x_clk)) - return PTR_ERR(pll_x_clk); - - pll_p_clk = clk_get_sys(NULL, "pll_p_cclk"); - if (IS_ERR(pll_p_clk)) - return PTR_ERR(pll_p_clk); - - emc_clk = clk_get_sys("cpu", "emc"); - if (IS_ERR(emc_clk)) { - clk_put(cpu_clk); - return PTR_ERR(emc_clk); - } - - return cpufreq_register_driver(&tegra_cpufreq_driver); -} - -static void __exit tegra_cpufreq_exit(void) -{ - cpufreq_unregister_driver(&tegra_cpufreq_driver); - clk_put(emc_clk); - clk_put(cpu_clk); -} - - -MODULE_AUTHOR("Colin Cross <ccross@android.com>"); -MODULE_DESCRIPTION("cpufreq driver for Nvidia Tegra2"); -MODULE_LICENSE("GPL"); -module_init(tegra_cpufreq_init); -module_exit(tegra_cpufreq_exit); |