2c2b24d9c3
The dbx500_cpuidle_probe is tagged as an __init section but the variable dbx500_cpuidle_plat_driver is not. The dbx500_cpuidle_probe could not be declared as __init because of macro module_platform_driver builds the exit function, tags as __exit and this one refers to the dbx500_cpuidle_plat_driver which is an __initdata. That leads to a section mismatch. Fix it by removing the __init tag for the probe function. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org>
132 lines
3.3 KiB
C
132 lines
3.3 KiB
C
/*
|
|
* Copyright (c) 2012 Linaro : Daniel Lezcano <daniel.lezcano@linaro.org> (IBM)
|
|
*
|
|
* Based on the work of Rickard Andersson <rickard.andersson@stericsson.com>
|
|
* and Jonas Aaberg <jonas.aberg@stericsson.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.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/mfd/dbx500-prcmu.h>
|
|
#include <linux/platform_data/arm-ux500-pm.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
#include <asm/cpuidle.h>
|
|
#include <asm/proc-fns.h>
|
|
|
|
static atomic_t master = ATOMIC_INIT(0);
|
|
static DEFINE_SPINLOCK(master_lock);
|
|
|
|
static inline int ux500_enter_idle(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int index)
|
|
{
|
|
int this_cpu = smp_processor_id();
|
|
bool recouple = false;
|
|
|
|
if (atomic_inc_return(&master) == num_online_cpus()) {
|
|
|
|
/* With this lock, we prevent the other cpu to exit and enter
|
|
* this function again and become the master */
|
|
if (!spin_trylock(&master_lock))
|
|
goto wfi;
|
|
|
|
/* decouple the gic from the A9 cores */
|
|
if (prcmu_gic_decouple()) {
|
|
spin_unlock(&master_lock);
|
|
goto out;
|
|
}
|
|
|
|
/* If an error occur, we will have to recouple the gic
|
|
* manually */
|
|
recouple = true;
|
|
|
|
/* At this state, as the gic is decoupled, if the other
|
|
* cpu is in WFI, we have the guarantee it won't be wake
|
|
* up, so we can safely go to retention */
|
|
if (!prcmu_is_cpu_in_wfi(this_cpu ? 0 : 1))
|
|
goto out;
|
|
|
|
/* The prcmu will be in charge of watching the interrupts
|
|
* and wake up the cpus */
|
|
if (prcmu_copy_gic_settings())
|
|
goto out;
|
|
|
|
/* Check in the meantime an interrupt did
|
|
* not occur on the gic ... */
|
|
if (prcmu_gic_pending_irq())
|
|
goto out;
|
|
|
|
/* ... and the prcmu */
|
|
if (prcmu_pending_irq())
|
|
goto out;
|
|
|
|
/* Go to the retention state, the prcmu will wait for the
|
|
* cpu to go WFI and this is what happens after exiting this
|
|
* 'master' critical section */
|
|
if (prcmu_set_power_state(PRCMU_AP_IDLE, true, true))
|
|
goto out;
|
|
|
|
/* When we switch to retention, the prcmu is in charge
|
|
* of recoupling the gic automatically */
|
|
recouple = false;
|
|
|
|
spin_unlock(&master_lock);
|
|
}
|
|
wfi:
|
|
cpu_do_idle();
|
|
out:
|
|
atomic_dec(&master);
|
|
|
|
if (recouple) {
|
|
prcmu_gic_recouple();
|
|
spin_unlock(&master_lock);
|
|
}
|
|
|
|
return index;
|
|
}
|
|
|
|
static struct cpuidle_driver ux500_idle_driver = {
|
|
.name = "ux500_idle",
|
|
.owner = THIS_MODULE,
|
|
.states = {
|
|
ARM_CPUIDLE_WFI_STATE,
|
|
{
|
|
.enter = ux500_enter_idle,
|
|
.exit_latency = 70,
|
|
.target_residency = 260,
|
|
.flags = CPUIDLE_FLAG_TIME_VALID |
|
|
CPUIDLE_FLAG_TIMER_STOP,
|
|
.name = "ApIdle",
|
|
.desc = "ARM Retention",
|
|
},
|
|
},
|
|
.safe_state_index = 0,
|
|
.state_count = 2,
|
|
};
|
|
|
|
static int dbx500_cpuidle_probe(struct platform_device *pdev)
|
|
{
|
|
/* Configure wake up reasons */
|
|
prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) |
|
|
PRCMU_WAKEUP(ABB));
|
|
|
|
return cpuidle_register(&ux500_idle_driver, NULL);
|
|
}
|
|
|
|
static struct platform_driver dbx500_cpuidle_plat_driver = {
|
|
.driver = {
|
|
.name = "cpuidle-dbx500",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = dbx500_cpuidle_probe,
|
|
};
|
|
|
|
module_platform_driver(dbx500_cpuidle_plat_driver);
|