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Release 4.11 drivers/cpufreq/highbank-cpufreq.c

Directory: drivers/cpufreq
/*
 * 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); }

Contributors

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Langsdorf, Mark2583.33%150.00%
Emilio López516.67%150.00%
Total30100.00%2100.00%


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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Langsdorf, Mark109100.00%1100.00%
Total109100.00%1100.00%

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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PersonTokensPropCommitsCommitProp
Langsdorf, Mark14980.54%240.00%
Sudeep KarkadaNagesha189.73%120.00%
Shawn Guo168.65%120.00%
Viresh Kumar21.08%120.00%
Total185100.00%5100.00%

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

PersonTokensPropCommitsCommitProp
Langsdorf, Mark35488.50%228.57%
Shawn Guo194.75%114.29%
Sudeep KarkadaNagesha184.50%114.29%
Emilio López51.25%114.29%
Viresh Kumar30.75%114.29%
Suman Anna10.25%114.29%
Total400100.00%7100.00%
Directory: drivers/cpufreq
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