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Release 4.14 drivers/cpufreq/loongson2_cpufreq.c

Directory: drivers/cpufreq
/*
 * Cpufreq driver for the loongson-2 processors
 *
 * The 2E revision of loongson processor not support this feature.
 *
 * Copyright (C) 2006 - 2008 Lemote Inc. & Institute of Computing Technology
 * Author: Yanhua, yanh@lemote.com
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/cpufreq.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/sched.h>	/* set_cpus_allowed() */
#include <linux/delay.h>
#include <linux/platform_device.h>

#include <asm/clock.h>
#include <asm/idle.h>

#include <asm/mach-loongson64/loongson.h>


static uint nowait;


static void (*saved_cpu_wait) (void);

static int loongson2_cpu_freq_notifier(struct notifier_block *nb,
					unsigned long val, void *data);


static struct notifier_block loongson2_cpufreq_notifier_block = {
	.notifier_call = loongson2_cpu_freq_notifier
};


static int loongson2_cpu_freq_notifier(struct notifier_block *nb, unsigned long val, void *data) { if (val == CPUFREQ_POSTCHANGE) current_cpu_data.udelay_val = loops_per_jiffy; return 0; }

Contributors

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Wu Zhangjin34100.00%1100.00%
Total34100.00%1100.00%

/* * Here we notify other drivers of the proposed change and the final change. */
static int loongson2_cpufreq_target(struct cpufreq_policy *policy, unsigned int index) { unsigned int freq; freq = ((cpu_clock_freq / 1000) * loongson2_clockmod_table[index].driver_data) / 8; /* setting the cpu frequency */ clk_set_rate(policy->clk, freq * 1000); return 0; }

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PersonTokensPropCommitsCommitProp
Wu Zhangjin4584.91%120.00%
Viresh Kumar611.32%360.00%
Aaro Koskinen23.77%120.00%
Total53100.00%5100.00%


static int loongson2_cpufreq_cpu_init(struct cpufreq_policy *policy) { struct clk *cpuclk; int i; unsigned long rate; int ret; cpuclk = clk_get(NULL, "cpu_clk"); if (IS_ERR(cpuclk)) { pr_err("couldn't get CPU clk\n"); return PTR_ERR(cpuclk); } rate = cpu_clock_freq / 1000; if (!rate) { clk_put(cpuclk); return -EINVAL; } /* clock table init */ for (i = 2; (loongson2_clockmod_table[i].frequency != CPUFREQ_TABLE_END); i++) loongson2_clockmod_table[i].frequency = (rate * i) / 8; ret = clk_set_rate(cpuclk, rate * 1000); if (ret) { clk_put(cpuclk); return ret; } policy->clk = cpuclk; return cpufreq_generic_init(policy, &loongson2_clockmod_table[0], 0); }

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PersonTokensPropCommitsCommitProp
Wu Zhangjin10365.19%112.50%
Aaro Koskinen2515.82%225.00%
Viresh Kumar148.86%225.00%
Julia Lawall148.86%112.50%
Joe Perches21.27%225.00%
Total158100.00%8100.00%


static int loongson2_cpufreq_exit(struct cpufreq_policy *policy) { clk_put(policy->clk); return 0; }

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Wu Zhangjin1885.71%150.00%
Viresh Kumar314.29%150.00%
Total21100.00%2100.00%

static struct cpufreq_driver loongson2_cpufreq_driver = { .name = "loongson2", .init = loongson2_cpufreq_cpu_init, .verify = cpufreq_generic_frequency_table_verify, .target_index = loongson2_cpufreq_target, .get = cpufreq_generic_get, .exit = loongson2_cpufreq_exit, .attr = cpufreq_generic_attr, }; static const struct platform_device_id platform_device_ids[] = { { .name = "loongson2_cpufreq", }, {} }; MODULE_DEVICE_TABLE(platform, platform_device_ids); static struct platform_driver platform_driver = { .driver = { .name = "loongson2_cpufreq", }, .id_table = platform_device_ids, }; /* * This is the simple version of Loongson-2 wait, Maybe we need do this in * interrupt disabled context. */ static DEFINE_SPINLOCK(loongson2_wait_lock);
static void loongson2_cpu_wait(void) { unsigned long flags; u32 cpu_freq; spin_lock_irqsave(&loongson2_wait_lock, flags); cpu_freq = LOONGSON_CHIPCFG(0); LOONGSON_CHIPCFG(0) &= ~0x7; /* Put CPU into wait mode */ LOONGSON_CHIPCFG(0) = cpu_freq; /* Restore CPU state */ spin_unlock_irqrestore(&loongson2_wait_lock, flags); local_irq_enable(); }

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Ralf Bächle4679.31%266.67%
Huacai Chen1220.69%133.33%
Total58100.00%3100.00%


static int __init cpufreq_init(void) { int ret; /* Register platform stuff */ ret = platform_driver_register(&platform_driver); if (ret) return ret; pr_info("Loongson-2F CPU frequency driver\n"); cpufreq_register_notifier(&loongson2_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER); ret = cpufreq_register_driver(&loongson2_cpufreq_driver); if (!ret && !nowait) { saved_cpu_wait = cpu_wait; cpu_wait = loongson2_cpu_wait; } return ret; }

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Wu Zhangjin6998.57%150.00%
Joe Perches11.43%150.00%
Total70100.00%2100.00%


static void __exit cpufreq_exit(void) { if (!nowait && saved_cpu_wait) cpu_wait = saved_cpu_wait; cpufreq_unregister_driver(&loongson2_cpufreq_driver); cpufreq_unregister_notifier(&loongson2_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER); platform_driver_unregister(&platform_driver); }

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Wu Zhangjin40100.00%1100.00%
Total40100.00%1100.00%

module_init(cpufreq_init); module_exit(cpufreq_exit); module_param(nowait, uint, 0644); MODULE_PARM_DESC(nowait, "Disable Loongson-2F specific wait"); MODULE_AUTHOR("Yanhua <yanh@lemote.com>"); MODULE_DESCRIPTION("cpufreq driver for Loongson2F"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Wu Zhangjin50377.15%15.56%
Ralf Bächle588.90%527.78%
Viresh Kumar274.14%527.78%
Aaro Koskinen274.14%211.11%
Julia Lawall142.15%15.56%
Huacai Chen121.84%15.56%
Joe Perches101.53%211.11%
Arvind Yadav10.15%15.56%
Total652100.00%18100.00%
Directory: drivers/cpufreq
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