Release 4.7 drivers/cpufreq/highbank-cpufreq.c
/*
* Copyright (C) 2012 Calxeda, Inc.
*
* 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.
*
* This driver provides the clk notifier callbacks that are used when
* the cpufreq-dt driver changes to frequency to alert the highbank
* EnergyCore Management Engine (ECME) about the need to change
* voltage. The ECME interfaces with the actual voltage regulators.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/cpu.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/pl320-ipc.h>
#include <linux/platform_device.h>
#define HB_CPUFREQ_CHANGE_NOTE 0x80000001
#define HB_CPUFREQ_IPC_LEN 7
#define HB_CPUFREQ_VOLT_RETRIES 15
static int hb_voltage_change(unsigned int freq)
{
u32 msg[HB_CPUFREQ_IPC_LEN] = {HB_CPUFREQ_CHANGE_NOTE, freq / 1000000};
return pl320_ipc_transmit(msg);
}
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| Total | 30 | 100.00% | 2 | 100.00% |
static int hb_cpufreq_clk_notify(struct notifier_block *nb,
unsigned long action, void *hclk)
{
struct clk_notifier_data *clk_data = hclk;
int i = 0;
if (action == PRE_RATE_CHANGE) {
if (clk_data->new_rate > clk_data->old_rate)
while (hb_voltage_change(clk_data->new_rate))
if (i++ > HB_CPUFREQ_VOLT_RETRIES)
return NOTIFY_BAD;
} else if (action == POST_RATE_CHANGE) {
if (clk_data->new_rate < clk_data->old_rate)
while (hb_voltage_change(clk_data->new_rate))
if (i++ > HB_CPUFREQ_VOLT_RETRIES)
return NOTIFY_BAD;
}
return NOTIFY_DONE;
}
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| Person | Tokens | Prop | Commits | CommitProp |
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static struct notifier_block hb_cpufreq_clk_nb = {
.notifier_call = hb_cpufreq_clk_notify,
};
static int hb_cpufreq_driver_init(void)
{
struct platform_device_info devinfo = { .name = "cpufreq-dt", };
struct device *cpu_dev;
struct clk *cpu_clk;
struct device_node *np;
int ret;
if ((!of_machine_is_compatible("calxeda,highbank")) &&
(!of_machine_is_compatible("calxeda,ecx-2000")))
return -ENODEV;
cpu_dev = get_cpu_device(0);
if (!cpu_dev) {
pr_err("failed to get highbank cpufreq device\n");
return -ENODEV;
}
np = of_node_get(cpu_dev->of_node);
if (!np) {
pr_err("failed to find highbank cpufreq node\n");
return -ENOENT;
}
cpu_clk = clk_get(cpu_dev, NULL);
if (IS_ERR(cpu_clk)) {
ret = PTR_ERR(cpu_clk);
pr_err("failed to get cpu0 clock: %d\n", ret);
goto out_put_node;
}
ret = clk_notifier_register(cpu_clk, &hb_cpufreq_clk_nb);
if (ret) {
pr_err("failed to register clk notifier: %d\n", ret);
goto out_put_node;
}
/* Instantiate cpufreq-dt */
platform_device_register_full(&devinfo);
out_put_node:
of_node_put(np);
return ret;
}
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| Person | Tokens | Prop | Commits | CommitProp |
| mark langsdorf | mark langsdorf | 149 | 80.54% | 2 | 40.00% |
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module_init(hb_cpufreq_driver_init);
MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@calxeda.com>");
MODULE_DESCRIPTION("Calxeda Highbank cpufreq driver");
MODULE_LICENSE("GPL");
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| mark langsdorf | mark langsdorf | 354 | 88.50% | 2 | 28.57% |
| shawn guo | shawn guo | 19 | 4.75% | 1 | 14.29% |
| sudeep karkadanagesha | sudeep karkadanagesha | 18 | 4.50% | 1 | 14.29% |
| emilio lopez | emilio lopez | 5 | 1.25% | 1 | 14.29% |
| viresh kumar | viresh kumar | 3 | 0.75% | 1 | 14.29% |
| suman anna | suman anna | 1 | 0.25% | 1 | 14.29% |
| Total | 400 | 100.00% | 7 | 100.00% |
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