linux_dsm_epyc7002/drivers/cpufreq/tegra-cpufreq.c

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/*
* 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>
static struct cpufreq_frequency_table freq_table[] = {
{ .frequency = 216000 },
{ .frequency = 312000 },
{ .frequency = 456000 },
{ .frequency = 608000 },
{ .frequency = 760000 },
{ .frequency = 816000 },
{ .frequency = 912000 },
{ .frequency = 1000000 },
{ .frequency = 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 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;
if (tegra_getspeed(0) == rate)
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 */
ret = tegra_cpu_clk_set_rate(rate * 1000);
if (ret)
pr_err("cpu-tegra: Failed to set cpu frequency to %lu kHz\n",
rate);
return ret;
}
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;
}
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 21:15:48 +07:00
static int tegra_target(struct cpufreq_policy *policy, unsigned int index)
{
unsigned int freq;
int ret = 0;
mutex_lock(&tegra_cpu_lock);
if (is_suspended)
goto out;
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 21:15:48 +07:00
freq = freq_table[index].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)
{
int ret;
if (policy->cpu >= NUM_CPUS)
return -EINVAL;
clk_prepare_enable(emc_clk);
clk_prepare_enable(cpu_clk);
target_cpu_speed[policy->cpu] = tegra_getspeed(policy->cpu);
/* FIXME: what's the actual transition time? */
ret = cpufreq_generic_init(policy, freq_table, 300 * 1000);
if (ret) {
clk_disable_unprepare(cpu_clk);
clk_disable_unprepare(emc_clk);
return ret;
}
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_put_attr(policy->cpu);
clk_disable_unprepare(cpu_clk);
clk_disable_unprepare(emc_clk);
return 0;
}
static struct cpufreq_driver tegra_cpufreq_driver = {
.verify = cpufreq_generic_frequency_table_verify,
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 21:15:48 +07:00
.target_index = tegra_target,
.get = tegra_getspeed,
.init = tegra_cpu_init,
.exit = tegra_cpu_exit,
.name = "tegra",
.attr = cpufreq_generic_attr,
};
static int __init tegra_cpufreq_init(void)
{
cpu_clk = clk_get_sys(NULL, "cclk");
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");
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);