hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

cpufreq: tegra20: Wrap cpufreq into platform driver 

Currently tegra20-cpufreq kernel module isn't getting autoloaded because
there is no device associated with the module, this is one of two patches
that resolves the module autoloading. This patch adds a module alias that
will associate the tegra20-cpufreq kernel module with the platform device,
other patch will instantiate the actual platform device. And now it makes
sense to wrap cpufreq driver into a platform driver for consistency.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Dmitry Osipenko 2018-05-18 23:06:42 +03:00 committed by Rafael J. Wysocki
parent 7732c9e0db
commit dc628cdf5c
1 changed files with 86 additions and 59 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

145
drivers/cpufreq/tegra20-cpufreq.c
View File

@ -21,7 +21,7 @@
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/types.h>
static struct cpufreq_frequency_table freq_table[] = {
@ -36,15 +36,20 @@ static struct cpufreq_frequency_table freq_table[] = {
{ .frequency = CPUFREQ_TABLE_END },
};
static struct clk *cpu_clk;
static struct clk *pll_x_clk;
static struct clk *pll_p_clk;
static bool pll_x_prepared;
struct tegra20_cpufreq {
struct device *dev;
struct cpufreq_driver driver;
struct clk *cpu_clk;
struct clk *pll_x_clk;
struct clk *pll_p_clk;
bool pll_x_prepared;
};
static unsigned int tegra_get_intermediate(struct cpufreq_policy *policy,
unsigned int index)
{
unsigned int ifreq = clk_get_rate(pll_p_clk) / 1000;
struct tegra20_cpufreq *cpufreq = cpufreq_get_driver_data();
unsigned int ifreq = clk_get_rate(cpufreq->pll_p_clk) / 1000;
/*
* Don't switch to intermediate freq if:
@ -60,6 +65,7 @@ static unsigned int tegra_get_intermediate(struct cpufreq_policy *policy,
static int tegra_target_intermediate(struct cpufreq_policy *policy,
unsigned int index)
{
struct tegra20_cpufreq *cpufreq = cpufreq_get_driver_data();
int ret;
/*
@ -72,21 +78,22 @@ static int tegra_target_intermediate(struct cpufreq_policy *policy,
* Also, we wouldn't be using pll_x anymore and must not take extra
* reference to it, as it can be disabled now to save some power.
*/
clk_prepare_enable(pll_x_clk);
clk_prepare_enable(cpufreq->pll_x_clk);
ret = clk_set_parent(cpu_clk, pll_p_clk);
ret = clk_set_parent(cpufreq->cpu_clk, cpufreq->pll_p_clk);
if (ret)
clk_disable_unprepare(pll_x_clk);
clk_disable_unprepare(cpufreq->pll_x_clk);
else
pll_x_prepared = true;
cpufreq->pll_x_prepared = true;
return ret;
}
static int tegra_target(struct cpufreq_policy *policy, unsigned int index)
{
struct tegra20_cpufreq *cpufreq = cpufreq_get_driver_data();
unsigned long rate = freq_table[index].frequency;
unsigned int ifreq = clk_get_rate(pll_p_clk) / 1000;
unsigned int ifreq = clk_get_rate(cpufreq->pll_p_clk) / 1000;
int ret;
/*
@ -94,14 +101,14 @@ static int tegra_target(struct cpufreq_policy *policy, unsigned int index)
* as it isn't used anymore.
*/
if (rate == ifreq)
return clk_set_parent(cpu_clk, pll_p_clk);
return clk_set_parent(cpufreq->cpu_clk, cpufreq->pll_p_clk);
ret = clk_set_rate(pll_x_clk, rate * 1000);
ret = clk_set_rate(cpufreq->pll_x_clk, rate * 1000);
/* Restore to earlier frequency on error, i.e. pll_x */
if (ret)
pr_err("Failed to change pll_x to %lu\n", rate);
dev_err(cpufreq->dev, "Failed to change pll_x to %lu\n", rate);
ret = clk_set_parent(cpu_clk, pll_x_clk);
ret = clk_set_parent(cpufreq->cpu_clk, cpufreq->pll_x_clk);
/* This shouldn't fail while changing or restoring */
WARN_ON(ret);
@ -109,9 +116,9 @@ static int tegra_target(struct cpufreq_policy *policy, unsigned int index)
* Drop count to pll_x clock only if we switched to intermediate freq
* earlier while transitioning to a target frequency.
*/
if (pll_x_prepared) {
clk_disable_unprepare(pll_x_clk);
pll_x_prepared = false;
if (cpufreq->pll_x_prepared) {
clk_disable_unprepare(cpufreq->pll_x_clk);
cpufreq->pll_x_prepared = false;
}
return ret;
@ -119,91 +126,111 @@ static int tegra_target(struct cpufreq_policy *policy, unsigned int index)
static int tegra_cpu_init(struct cpufreq_policy *policy)
{
struct tegra20_cpufreq *cpufreq = cpufreq_get_driver_data();
int ret;
clk_prepare_enable(cpu_clk);
clk_prepare_enable(cpufreq->cpu_clk);
/* 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(cpufreq->cpu_clk);
return ret;
}
policy->clk = cpu_clk;
policy->clk = cpufreq->cpu_clk;
policy->suspend_freq = freq_table[0].frequency;
return 0;
}
static int tegra_cpu_exit(struct cpufreq_policy *policy)
{
clk_disable_unprepare(cpu_clk);
struct tegra20_cpufreq *cpufreq = cpufreq_get_driver_data();
clk_disable_unprepare(cpufreq->cpu_clk);
return 0;
}
static struct cpufreq_driver tegra_cpufreq_driver = {
.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.verify = cpufreq_generic_frequency_table_verify,
.get_intermediate = tegra_get_intermediate,
.target_intermediate = tegra_target_intermediate,
.target_index = tegra_target,
.get = cpufreq_generic_get,
.init = tegra_cpu_init,
.exit = tegra_cpu_exit,
.name = "tegra",
.attr = cpufreq_generic_attr,
.suspend = cpufreq_generic_suspend,
};
static int __init tegra_cpufreq_init(void)
static int tegra20_cpufreq_probe(struct platform_device *pdev)
{
struct tegra20_cpufreq *cpufreq;
int err;
if (!of_machine_is_compatible("nvidia,tegra20"))
return -ENODEV;
cpufreq = devm_kzalloc(&pdev->dev, sizeof(*cpufreq), GFP_KERNEL);
if (!cpufreq)
return -ENOMEM;
cpu_clk = clk_get_sys(NULL, "cclk");
if (IS_ERR(cpu_clk))
return PTR_ERR(cpu_clk);
cpufreq->cpu_clk = clk_get_sys(NULL, "cclk");
if (IS_ERR(cpufreq->cpu_clk))
return PTR_ERR(cpufreq->cpu_clk);
pll_x_clk = clk_get_sys(NULL, "pll_x");
if (IS_ERR(pll_x_clk)) {
err = PTR_ERR(pll_x_clk);
cpufreq->pll_x_clk = clk_get_sys(NULL, "pll_x");
if (IS_ERR(cpufreq->pll_x_clk)) {
err = PTR_ERR(cpufreq->pll_x_clk);
goto put_cpu;
}
pll_p_clk = clk_get_sys(NULL, "pll_p");
if (IS_ERR(pll_p_clk)) {
err = PTR_ERR(pll_p_clk);
cpufreq->pll_p_clk = clk_get_sys(NULL, "pll_p");
if (IS_ERR(cpufreq->pll_p_clk)) {
err = PTR_ERR(cpufreq->pll_p_clk);
goto put_pll_x;
}
err = cpufreq_register_driver(&tegra_cpufreq_driver);
cpufreq->dev = &pdev->dev;
cpufreq->driver.get = cpufreq_generic_get;
cpufreq->driver.attr = cpufreq_generic_attr;
cpufreq->driver.init = tegra_cpu_init;
cpufreq->driver.exit = tegra_cpu_exit;
cpufreq->driver.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK;
cpufreq->driver.verify = cpufreq_generic_frequency_table_verify;
cpufreq->driver.suspend = cpufreq_generic_suspend;
cpufreq->driver.driver_data = cpufreq;
cpufreq->driver.target_index = tegra_target;
cpufreq->driver.get_intermediate = tegra_get_intermediate;
cpufreq->driver.target_intermediate = tegra_target_intermediate;
snprintf(cpufreq->driver.name, CPUFREQ_NAME_LEN, "tegra");
err = cpufreq_register_driver(&cpufreq->driver);
if (err)
goto put_pll_p;
platform_set_drvdata(pdev, cpufreq);
return 0;
put_pll_p:
clk_put(pll_p_clk);
clk_put(cpufreq->pll_p_clk);
put_pll_x:
clk_put(pll_x_clk);
clk_put(cpufreq->pll_x_clk);
put_cpu:
clk_put(cpu_clk);
clk_put(cpufreq->cpu_clk);
return err;
}
static void __exit tegra_cpufreq_exit(void)
static int tegra20_cpufreq_remove(struct platform_device *pdev)
{
cpufreq_unregister_driver(&tegra_cpufreq_driver);
clk_put(pll_p_clk);
clk_put(pll_x_clk);
clk_put(cpu_clk);
struct tegra20_cpufreq *cpufreq = platform_get_drvdata(pdev);
cpufreq_unregister_driver(&cpufreq->driver);
clk_put(cpufreq->pll_p_clk);
clk_put(cpufreq->pll_x_clk);
clk_put(cpufreq->cpu_clk);
return 0;
}
static struct platform_driver tegra20_cpufreq_driver = {
.probe = tegra20_cpufreq_probe,
.remove = tegra20_cpufreq_remove,
.driver = {
.name = "tegra20-cpufreq",
},
};
module_platform_driver(tegra20_cpufreq_driver);
MODULE_ALIAS("platform:tegra20-cpufreq");
MODULE_AUTHOR("Colin Cross <ccross@android.com>");
MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
MODULE_LICENSE("GPL");
module_init(tegra_cpufreq_init);
module_exit(tegra_cpufreq_exit);