cregit-Linux how code gets into the kernel

Release 4.17 drivers/cpuidle/cpuidle-arm.c

Directory: drivers/cpuidle
/*
 * ARM/ARM64 generic CPU idle driver.
 *
 * Copyright (C) 2014 ARM Ltd.
 * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
 *
 * 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.
 */


#define pr_fmt(fmt) "CPUidle arm: " fmt

#include <linux/cpuidle.h>
#include <linux/cpumask.h>
#include <linux/cpu_pm.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/topology.h>

#include <asm/cpuidle.h>

#include "dt_idle_states.h"

/*
 * arm_enter_idle_state - Programs CPU to enter the specified state
 *
 * dev: cpuidle device
 * drv: cpuidle driver
 * idx: state index
 *
 * Called from the CPUidle framework to program the device to the
 * specified target state selected by the governor.
 */

static int arm_enter_idle_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, int idx) { /* * Pass idle state index to arm_cpuidle_suspend which in turn * will call the CPU ops suspend protocol with idle index as a * parameter. */ return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, idx); }

Contributors

PersonTokensPropCommitsCommitProp
Lorenzo Pieralisi2382.14%133.33%
Sudeep Holla414.29%133.33%
Daniel Lezcano13.57%133.33%
Total28100.00%3100.00%

static struct cpuidle_driver arm_idle_driver __initdata = { .name = "arm_idle", .owner = THIS_MODULE, /* * State at index 0 is standby wfi and considered standard * on all ARM platforms. If in some platforms simple wfi * can't be used as "state 0", DT bindings must be implemented * to work around this issue and allow installing a special * handler for idle state index 0. */ .states[0] = { .enter = arm_enter_idle_state, .exit_latency = 1, .target_residency = 1, .power_usage = UINT_MAX, .name = "WFI", .desc = "ARM WFI", } }; static const struct of_device_id arm_idle_state_match[] __initconst = { { .compatible = "arm,idle-state", .data = arm_enter_idle_state }, { }, }; /* * arm_idle_init_cpu * * Registers the arm specific cpuidle driver with the cpuidle * framework. It relies on core code to parse the idle states * and initialize them using driver data structures accordingly. */
static int __init arm_idle_init_cpu(int cpu) { int ret; struct cpuidle_driver *drv; struct cpuidle_device *dev; drv = kmemdup(&arm_idle_driver, sizeof(*drv), GFP_KERNEL); if (!drv) return -ENOMEM; drv->cpumask = (struct cpumask *)cpumask_of(cpu); /* * Initialize idle states data, starting at index 1. This * driver is DT only, if no DT idle states are detected (ret * == 0) let the driver initialization fail accordingly since * there is no reason to initialize the idle driver if only * wfi is supported. */ ret = dt_init_idle_driver(drv, arm_idle_state_match, 1); if (ret <= 0) { ret = ret ? : -ENODEV; goto out_kfree_drv; } ret = cpuidle_register_driver(drv); if (ret) { pr_err("Failed to register cpuidle driver\n"); goto out_kfree_drv; } /* * Call arch CPU operations in order to initialize * idle states suspend back-end specific data */ ret = arm_cpuidle_init(cpu); /* * Skip the cpuidle device initialization if the reported * failure is a HW misconfiguration/breakage (-ENXIO). */ if (ret == -ENXIO) return 0; if (ret) { pr_err("CPU %d failed to init idle CPU ops\n", cpu); goto out_unregister_drv; } dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) { ret = -ENOMEM; goto out_unregister_drv; } dev->cpu = cpu; ret = cpuidle_register_device(dev); if (ret) { pr_err("Failed to register cpuidle device for CPU %d\n", cpu); goto out_kfree_dev; } return 0; out_kfree_dev: kfree(dev); out_unregister_drv: cpuidle_unregister_driver(drv); out_kfree_drv: kfree(drv); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Daniel Lezcano13156.22%440.00%
Lorenzo Pieralisi5624.03%220.00%
Leo Yan3515.02%220.00%
Stefan Wahren62.58%110.00%
Christophe Jaillet52.15%110.00%
Total233100.00%10100.00%

/* * arm_idle_init - Initializes arm cpuidle driver * * Initializes arm cpuidle driver for all CPUs, if any CPU fails * to register cpuidle driver then rollback to cancel all CPUs * registeration. */
static int __init arm_idle_init(void) { int cpu, ret; struct cpuidle_driver *drv; struct cpuidle_device *dev; for_each_possible_cpu(cpu) { ret = arm_idle_init_cpu(cpu); if (ret) goto out_fail; } return 0; out_fail: while (--cpu >= 0) { dev = per_cpu(cpuidle_devices, cpu); drv = cpuidle_get_cpu_driver(dev); cpuidle_unregister_device(dev); cpuidle_unregister_driver(drv); kfree(dev); kfree(drv); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Leo Yan5556.70%240.00%
Daniel Lezcano3738.14%240.00%
Lorenzo Pieralisi55.15%120.00%
Total97100.00%5100.00%

device_initcall(arm_idle_init);

Overall Contributors

PersonTokensPropCommitsCommitProp
Lorenzo Pieralisi19239.59%218.18%
Daniel Lezcano18638.35%436.36%
Leo Yan9218.97%218.18%
Stefan Wahren61.24%19.09%
Christophe Jaillet51.03%19.09%
Sudeep Holla40.82%19.09%
Total485100.00%11100.00%
Directory: drivers/cpuidle
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.