mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Pali Rohár](/assets/img/avatar_default.png)
This patch adds missing MODULE_DEVICE_TABLE definition which generates
correct modalias for automatic loading of this cpufreq driver when it is
compiled as an external module.
Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: f525a67053
("cpufreq: ap806: add cpufreq driver for Armada 8K")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
215 lines
4.9 KiB
C
215 lines
4.9 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* CPUFreq support for Armada 8K
|
|
*
|
|
* Copyright (C) 2018 Marvell
|
|
*
|
|
* Omri Itach <omrii@marvell.com>
|
|
* Gregory Clement <gregory.clement@bootlin.com>
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/clk.h>
|
|
#include <linux/cpu.h>
|
|
#include <linux/err.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/pm_opp.h>
|
|
#include <linux/slab.h>
|
|
|
|
/*
|
|
* Setup the opps list with the divider for the max frequency, that
|
|
* will be filled at runtime.
|
|
*/
|
|
static const int opps_div[] __initconst = {1, 2, 3, 4};
|
|
|
|
static struct platform_device *armada_8k_pdev;
|
|
|
|
struct freq_table {
|
|
struct device *cpu_dev;
|
|
unsigned int freq[ARRAY_SIZE(opps_div)];
|
|
};
|
|
|
|
/* If the CPUs share the same clock, then they are in the same cluster. */
|
|
static void __init armada_8k_get_sharing_cpus(struct clk *cur_clk,
|
|
struct cpumask *cpumask)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct device *cpu_dev;
|
|
struct clk *clk;
|
|
|
|
cpu_dev = get_cpu_device(cpu);
|
|
if (!cpu_dev) {
|
|
pr_warn("Failed to get cpu%d device\n", cpu);
|
|
continue;
|
|
}
|
|
|
|
clk = clk_get(cpu_dev, 0);
|
|
if (IS_ERR(clk)) {
|
|
pr_warn("Cannot get clock for CPU %d\n", cpu);
|
|
} else {
|
|
if (clk_is_match(clk, cur_clk))
|
|
cpumask_set_cpu(cpu, cpumask);
|
|
|
|
clk_put(clk);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __init armada_8k_add_opp(struct clk *clk, struct device *cpu_dev,
|
|
struct freq_table *freq_tables,
|
|
int opps_index)
|
|
{
|
|
unsigned int cur_frequency;
|
|
unsigned int freq;
|
|
int i, ret;
|
|
|
|
/* Get nominal (current) CPU frequency. */
|
|
cur_frequency = clk_get_rate(clk);
|
|
if (!cur_frequency) {
|
|
dev_err(cpu_dev, "Failed to get clock rate for this CPU\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
freq_tables[opps_index].cpu_dev = cpu_dev;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(opps_div); i++) {
|
|
freq = cur_frequency / opps_div[i];
|
|
|
|
ret = dev_pm_opp_add(cpu_dev, freq, 0);
|
|
if (ret)
|
|
return ret;
|
|
|
|
freq_tables[opps_index].freq[i] = freq;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void armada_8k_cpufreq_free_table(struct freq_table *freq_tables)
|
|
{
|
|
int opps_index, nb_cpus = num_possible_cpus();
|
|
|
|
for (opps_index = 0 ; opps_index <= nb_cpus; opps_index++) {
|
|
int i;
|
|
|
|
/* If cpu_dev is NULL then we reached the end of the array */
|
|
if (!freq_tables[opps_index].cpu_dev)
|
|
break;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(opps_div); i++) {
|
|
/*
|
|
* A 0Hz frequency is not valid, this meant
|
|
* that it was not yet initialized so there is
|
|
* no more opp to free
|
|
*/
|
|
if (freq_tables[opps_index].freq[i] == 0)
|
|
break;
|
|
|
|
dev_pm_opp_remove(freq_tables[opps_index].cpu_dev,
|
|
freq_tables[opps_index].freq[i]);
|
|
}
|
|
}
|
|
|
|
kfree(freq_tables);
|
|
}
|
|
|
|
static int __init armada_8k_cpufreq_init(void)
|
|
{
|
|
int ret = 0, opps_index = 0, cpu, nb_cpus;
|
|
struct freq_table *freq_tables;
|
|
struct device_node *node;
|
|
struct cpumask cpus;
|
|
|
|
node = of_find_compatible_node(NULL, NULL, "marvell,ap806-cpu-clock");
|
|
if (!node || !of_device_is_available(node)) {
|
|
of_node_put(node);
|
|
return -ENODEV;
|
|
}
|
|
of_node_put(node);
|
|
|
|
nb_cpus = num_possible_cpus();
|
|
freq_tables = kcalloc(nb_cpus, sizeof(*freq_tables), GFP_KERNEL);
|
|
if (!freq_tables)
|
|
return -ENOMEM;
|
|
cpumask_copy(&cpus, cpu_possible_mask);
|
|
|
|
/*
|
|
* For each CPU, this loop registers the operating points
|
|
* supported (which are the nominal CPU frequency and full integer
|
|
* divisions of it).
|
|
*/
|
|
for_each_cpu(cpu, &cpus) {
|
|
struct cpumask shared_cpus;
|
|
struct device *cpu_dev;
|
|
struct clk *clk;
|
|
|
|
cpu_dev = get_cpu_device(cpu);
|
|
|
|
if (!cpu_dev) {
|
|
pr_err("Cannot get CPU %d\n", cpu);
|
|
continue;
|
|
}
|
|
|
|
clk = clk_get(cpu_dev, 0);
|
|
|
|
if (IS_ERR(clk)) {
|
|
pr_err("Cannot get clock for CPU %d\n", cpu);
|
|
ret = PTR_ERR(clk);
|
|
goto remove_opp;
|
|
}
|
|
|
|
ret = armada_8k_add_opp(clk, cpu_dev, freq_tables, opps_index);
|
|
if (ret) {
|
|
clk_put(clk);
|
|
goto remove_opp;
|
|
}
|
|
|
|
opps_index++;
|
|
cpumask_clear(&shared_cpus);
|
|
armada_8k_get_sharing_cpus(clk, &shared_cpus);
|
|
dev_pm_opp_set_sharing_cpus(cpu_dev, &shared_cpus);
|
|
cpumask_andnot(&cpus, &cpus, &shared_cpus);
|
|
clk_put(clk);
|
|
}
|
|
|
|
armada_8k_pdev = platform_device_register_simple("cpufreq-dt", -1,
|
|
NULL, 0);
|
|
ret = PTR_ERR_OR_ZERO(armada_8k_pdev);
|
|
if (ret)
|
|
goto remove_opp;
|
|
|
|
platform_set_drvdata(armada_8k_pdev, freq_tables);
|
|
|
|
return 0;
|
|
|
|
remove_opp:
|
|
armada_8k_cpufreq_free_table(freq_tables);
|
|
return ret;
|
|
}
|
|
module_init(armada_8k_cpufreq_init);
|
|
|
|
static void __exit armada_8k_cpufreq_exit(void)
|
|
{
|
|
struct freq_table *freq_tables = platform_get_drvdata(armada_8k_pdev);
|
|
|
|
platform_device_unregister(armada_8k_pdev);
|
|
armada_8k_cpufreq_free_table(freq_tables);
|
|
}
|
|
module_exit(armada_8k_cpufreq_exit);
|
|
|
|
static const struct of_device_id __maybe_unused armada_8k_cpufreq_of_match[] = {
|
|
{ .compatible = "marvell,ap806-cpu-clock" },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, armada_8k_cpufreq_of_match);
|
|
|
|
MODULE_AUTHOR("Gregory Clement <gregory.clement@bootlin.com>");
|
|
MODULE_DESCRIPTION("Armada 8K cpufreq driver");
|
|
MODULE_LICENSE("GPL");
|