drivers/cpufreq/omap-cpufreq.c - maze/linux - Git at Google

 /*
  *  CPU frequency scaling for OMAP
  *
  *  Copyright (C) 2005 Nokia Corporation
  *  Written by Tony Lindgren <tony@atomide.com>
  *
  *  Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
  *
  * Copyright (C) 2007-2011 Texas Instruments, Inc.
  * - OMAP3/4 support by Rajendra Nayak, Santosh Shilimkar
  *
  * 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/types.h>
 #include <linux/kernel.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/opp.h>
 #include <linux/cpu.h>

 #include <asm/system.h>
 #include <asm/smp_plat.h>
 #include <asm/cpu.h>

 #include <plat/clock.h>
 #include <plat/omap-pm.h>
 #include <plat/common.h>

 #include <mach/hardware.h>

 #define VERY_HI_RATE	900000000

 #ifdef CONFIG_SMP
 struct lpj_info {
 	unsigned long	ref;
 	unsigned int	freq;
 };

 static DEFINE_PER_CPU(struct lpj_info, lpj_ref);
 static struct lpj_info global_lpj_ref;
 #endif

 static struct cpufreq_frequency_table *freq_table;
 static struct clk *mpu_clk;

 static int omap_verify_speed(struct cpufreq_policy *policy)
 {
 	if (freq_table)
 		return cpufreq_frequency_table_verify(policy, freq_table);

 	if (policy->cpu)
 		return -EINVAL;

 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
 				     policy->cpuinfo.max_freq);

 	policy->min = clk_round_rate(mpu_clk, policy->min * 1000) / 1000;
 	policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000;
 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
 				     policy->cpuinfo.max_freq);
 	return 0;
 }

 static unsigned int omap_getspeed(unsigned int cpu)
 {
 	unsigned long rate;

 	if (cpu >= NR_CPUS)
 		return 0;

 	rate = clk_get_rate(mpu_clk) / 1000;
 	return rate;
 }

 static int omap_target(struct cpufreq_policy *policy,
 		       unsigned int target_freq,
 		       unsigned int relation)
 {
 	int i, ret = 0;
 	struct cpufreq_freqs freqs;

 	/* Ensure desired rate is within allowed range.  Some govenors
 	 * (ondemand) will just pass target_freq=0 to get the minimum. */
 	if (target_freq < policy->min)
 		target_freq = policy->min;
 	if (target_freq > policy->max)
 		target_freq = policy->max;

 	freqs.old = omap_getspeed(policy->cpu);
 	freqs.new = clk_round_rate(mpu_clk, target_freq * 1000) / 1000;
 	freqs.cpu = policy->cpu;

 	if (freqs.old == freqs.new && policy->cur == freqs.new)
 		return ret;

 	/* notifiers */
 	for_each_cpu(i, policy->cpus) {
 		freqs.cpu = i;
 		cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 	}

 #ifdef CONFIG_CPU_FREQ_DEBUG
 	pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new);
 #endif

 	ret = clk_set_rate(mpu_clk, freqs.new * 1000);
 	freqs.new = omap_getspeed(policy->cpu);

 #ifdef CONFIG_SMP
 	/*
 	 * Note that loops_per_jiffy is not updated on SMP systems in
 	 * cpufreq driver. So, update the per-CPU loops_per_jiffy value
 	 * on frequency transition. We need to update all dependent CPUs.
 	 */
 	for_each_cpu(i, policy->cpus) {
 		struct lpj_info *lpj = &per_cpu(lpj_ref, i);
 		if (!lpj->freq) {
 			lpj->ref = per_cpu(cpu_data, i).loops_per_jiffy;
 			lpj->freq = freqs.old;
 		}

 		per_cpu(cpu_data, i).loops_per_jiffy =
 			cpufreq_scale(lpj->ref, lpj->freq, freqs.new);
 	}

 	/* And don't forget to adjust the global one */
 	if (!global_lpj_ref.freq) {
 		global_lpj_ref.ref = loops_per_jiffy;
 		global_lpj_ref.freq = freqs.old;
 	}
 	loops_per_jiffy = cpufreq_scale(global_lpj_ref.ref, global_lpj_ref.freq,
 					freqs.new);
 #endif

 	/* notifiers */
 	for_each_cpu(i, policy->cpus) {
 		freqs.cpu = i;
 		cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 	}

 	return ret;
 }

 static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy)
 {
 	int result = 0;
 	struct device *mpu_dev;

 	if (cpu_is_omap24xx())
 		mpu_clk = clk_get(NULL, "virt_prcm_set");
 	else if (cpu_is_omap34xx())
 		mpu_clk = clk_get(NULL, "dpll1_ck");
 	else if (cpu_is_omap44xx())
 		mpu_clk = clk_get(NULL, "dpll_mpu_ck");

 	if (IS_ERR(mpu_clk))
 		return PTR_ERR(mpu_clk);

 	if (policy->cpu >= NR_CPUS)
 		return -EINVAL;

 	policy->cur = policy->min = policy->max = omap_getspeed(policy->cpu);
 	mpu_dev = omap2_get_mpuss_device();

 	if (!mpu_dev) {
 		pr_warning("%s: unable to get the mpu device\n", __func__);
 		return -EINVAL;
 	}
 	opp_init_cpufreq_table(mpu_dev, &freq_table);

 	if (freq_table) {
 		result = cpufreq_frequency_table_cpuinfo(policy, freq_table);
 		if (!result)
 			cpufreq_frequency_table_get_attr(freq_table,
 							policy->cpu);
 	} else {
 		policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
 		policy->cpuinfo.max_freq = clk_round_rate(mpu_clk,
 							VERY_HI_RATE) / 1000;
 	}

 	policy->min = policy->cpuinfo.min_freq;
 	policy->max = policy->cpuinfo.max_freq;
 	policy->cur = omap_getspeed(policy->cpu);

 	/*
 	 * On OMAP SMP configuartion, both processors share the voltage
 	 * and clock. So both CPUs needs to be scaled together and hence
 	 * needs software co-ordination. Use cpufreq affected_cpus
 	 * interface to handle this scenario. Additional is_smp() check
 	 * is to keep SMP_ON_UP build working.
 	 */
 	if (is_smp()) {
 		policy->shared_type = CPUFREQ_SHARED_TYPE_ANY;
 		cpumask_setall(policy->cpus);
 	}

 	/* FIXME: what's the actual transition time? */
 	policy->cpuinfo.transition_latency = 300 * 1000;

 	return 0;
 }

 static int omap_cpu_exit(struct cpufreq_policy *policy)
 {
 	clk_exit_cpufreq_table(&freq_table);
 	clk_put(mpu_clk);
 	return 0;
 }

 static struct freq_attr *omap_cpufreq_attr[] = {
 	&cpufreq_freq_attr_scaling_available_freqs,
 	NULL,
 };

 static struct cpufreq_driver omap_driver = {
 	.flags		= CPUFREQ_STICKY,
 	.verify		= omap_verify_speed,
 	.target		= omap_target,
 	.get		= omap_getspeed,
 	.init		= omap_cpu_init,
 	.exit		= omap_cpu_exit,
 	.name		= "omap",
 	.attr		= omap_cpufreq_attr,
 };

 static int __init omap_cpufreq_init(void)
 {
 	return cpufreq_register_driver(&omap_driver);
 }

 static void __exit omap_cpufreq_exit(void)
 {
 	cpufreq_unregister_driver(&omap_driver);
 }

 MODULE_DESCRIPTION("cpufreq driver for OMAP SoCs");
 MODULE_LICENSE("GPL");
 module_init(omap_cpufreq_init);
 module_exit(omap_cpufreq_exit);
	/*
	* CPU frequency scaling for OMAP
	*
	* Copyright (C) 2005 Nokia Corporation
	* Written by Tony Lindgren <tony@atomide.com>
	*
	* Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
	*
	* Copyright (C) 2007-2011 Texas Instruments, Inc.
	* - OMAP3/4 support by Rajendra Nayak, Santosh Shilimkar
	*
	* 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/types.h>
	#include <linux/kernel.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/opp.h>
	#include <linux/cpu.h>

	#include <asm/system.h>
	#include <asm/smp_plat.h>
	#include <asm/cpu.h>

	#include <plat/clock.h>
	#include <plat/omap-pm.h>
	#include <plat/common.h>

	#include <mach/hardware.h>

	#define VERY_HI_RATE 900000000

	#ifdef CONFIG_SMP
	struct lpj_info {
	unsigned long ref;
	unsigned int freq;
	};

	static DEFINE_PER_CPU(struct lpj_info, lpj_ref);
	static struct lpj_info global_lpj_ref;
	#endif

	static struct cpufreq_frequency_table *freq_table;
	static struct clk *mpu_clk;

	static int omap_verify_speed(struct cpufreq_policy *policy)
	{
	if (freq_table)
	return cpufreq_frequency_table_verify(policy, freq_table);

	if (policy->cpu)
	return -EINVAL;

	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
	policy->cpuinfo.max_freq);

	policy->min = clk_round_rate(mpu_clk, policy->min * 1000) / 1000;
	policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000;
	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
	policy->cpuinfo.max_freq);
	return 0;
	}

	static unsigned int omap_getspeed(unsigned int cpu)
	{
	unsigned long rate;

	if (cpu >= NR_CPUS)
	return 0;

	rate = clk_get_rate(mpu_clk) / 1000;
	return rate;
	}

	static int omap_target(struct cpufreq_policy *policy,
	unsigned int target_freq,
	unsigned int relation)
	{
	int i, ret = 0;
	struct cpufreq_freqs freqs;

	/* Ensure desired rate is within allowed range. Some govenors
	* (ondemand) will just pass target_freq=0 to get the minimum. */
	if (target_freq < policy->min)
	target_freq = policy->min;
	if (target_freq > policy->max)
	target_freq = policy->max;

	freqs.old = omap_getspeed(policy->cpu);
	freqs.new = clk_round_rate(mpu_clk, target_freq * 1000) / 1000;
	freqs.cpu = policy->cpu;

	if (freqs.old == freqs.new && policy->cur == freqs.new)
	return ret;

	/* notifiers */
	for_each_cpu(i, policy->cpus) {
	freqs.cpu = i;
	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	}

	#ifdef CONFIG_CPU_FREQ_DEBUG
	pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new);
	#endif

	ret = clk_set_rate(mpu_clk, freqs.new * 1000);
	freqs.new = omap_getspeed(policy->cpu);

	#ifdef CONFIG_SMP
	/*
	* Note that loops_per_jiffy is not updated on SMP systems in
	* cpufreq driver. So, update the per-CPU loops_per_jiffy value
	* on frequency transition. We need to update all dependent CPUs.
	*/
	for_each_cpu(i, policy->cpus) {
	struct lpj_info *lpj = &per_cpu(lpj_ref, i);
	if (!lpj->freq) {
	lpj->ref = per_cpu(cpu_data, i).loops_per_jiffy;
	lpj->freq = freqs.old;
	}

	per_cpu(cpu_data, i).loops_per_jiffy =
	cpufreq_scale(lpj->ref, lpj->freq, freqs.new);
	}

	/* And don't forget to adjust the global one */
	if (!global_lpj_ref.freq) {
	global_lpj_ref.ref = loops_per_jiffy;
	global_lpj_ref.freq = freqs.old;
	}
	loops_per_jiffy = cpufreq_scale(global_lpj_ref.ref, global_lpj_ref.freq,
	freqs.new);
	#endif

	/* notifiers */
	for_each_cpu(i, policy->cpus) {
	freqs.cpu = i;
	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
	}

	return ret;
	}

	static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy)
	{
	int result = 0;
	struct device *mpu_dev;

	if (cpu_is_omap24xx())
	mpu_clk = clk_get(NULL, "virt_prcm_set");
	else if (cpu_is_omap34xx())
	mpu_clk = clk_get(NULL, "dpll1_ck");
	else if (cpu_is_omap44xx())
	mpu_clk = clk_get(NULL, "dpll_mpu_ck");

	if (IS_ERR(mpu_clk))
	return PTR_ERR(mpu_clk);

	if (policy->cpu >= NR_CPUS)
	return -EINVAL;

	policy->cur = policy->min = policy->max = omap_getspeed(policy->cpu);
	mpu_dev = omap2_get_mpuss_device();

	if (!mpu_dev) {
	pr_warning("%s: unable to get the mpu device\n", __func__);
	return -EINVAL;
	}
	opp_init_cpufreq_table(mpu_dev, &freq_table);

	if (freq_table) {
	result = cpufreq_frequency_table_cpuinfo(policy, freq_table);
	if (!result)
	cpufreq_frequency_table_get_attr(freq_table,
	policy->cpu);
	} else {
	policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000;
	policy->cpuinfo.max_freq = clk_round_rate(mpu_clk,
	VERY_HI_RATE) / 1000;
	}

	policy->min = policy->cpuinfo.min_freq;
	policy->max = policy->cpuinfo.max_freq;
	policy->cur = omap_getspeed(policy->cpu);

	/*
	* On OMAP SMP configuartion, both processors share the voltage
	* and clock. So both CPUs needs to be scaled together and hence
	* needs software co-ordination. Use cpufreq affected_cpus
	* interface to handle this scenario. Additional is_smp() check
	* is to keep SMP_ON_UP build working.
	*/
	if (is_smp()) {
	policy->shared_type = CPUFREQ_SHARED_TYPE_ANY;
	cpumask_setall(policy->cpus);
	}

	/* FIXME: what's the actual transition time? */
	policy->cpuinfo.transition_latency = 300 * 1000;

	return 0;
	}

	static int omap_cpu_exit(struct cpufreq_policy *policy)
	{
	clk_exit_cpufreq_table(&freq_table);
	clk_put(mpu_clk);
	return 0;
	}

	static struct freq_attr *omap_cpufreq_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	NULL,
	};

	static struct cpufreq_driver omap_driver = {
	.flags = CPUFREQ_STICKY,
	.verify = omap_verify_speed,
	.target = omap_target,
	.get = omap_getspeed,
	.init = omap_cpu_init,
	.exit = omap_cpu_exit,
	.name = "omap",
	.attr = omap_cpufreq_attr,
	};

	static int __init omap_cpufreq_init(void)
	{
	return cpufreq_register_driver(&omap_driver);
	}

	static void __exit omap_cpufreq_exit(void)
	{
	cpufreq_unregister_driver(&omap_driver);
	}

	MODULE_DESCRIPTION("cpufreq driver for OMAP SoCs");
	MODULE_LICENSE("GPL");
	module_init(omap_cpufreq_init);
	module_exit(omap_cpufreq_exit);