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b82b6cca48
The only place where the time is invalid is when the ACPI_CSTATE_FFH entry method is not set. Otherwise for all the drivers, the time can be correctly measured. Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers for all the states, just invert the logic by replacing it by the flag CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle driver, remove the former flag from all the drivers and invert the logic with this flag in the different governor. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
131 lines
3.2 KiB
C
131 lines
3.2 KiB
C
/*
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* Copyright (c) 2012 Linaro : Daniel Lezcano <daniel.lezcano@linaro.org> (IBM)
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*
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* Based on the work of Rickard Andersson <rickard.andersson@stericsson.com>
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* and Jonas Aaberg <jonas.aberg@stericsson.com>.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/cpuidle.h>
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#include <linux/spinlock.h>
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#include <linux/atomic.h>
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#include <linux/smp.h>
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#include <linux/mfd/dbx500-prcmu.h>
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#include <linux/platform_data/arm-ux500-pm.h>
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#include <linux/platform_device.h>
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#include <asm/cpuidle.h>
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#include <asm/proc-fns.h>
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static atomic_t master = ATOMIC_INIT(0);
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static DEFINE_SPINLOCK(master_lock);
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static inline int ux500_enter_idle(struct cpuidle_device *dev,
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struct cpuidle_driver *drv, int index)
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{
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int this_cpu = smp_processor_id();
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bool recouple = false;
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if (atomic_inc_return(&master) == num_online_cpus()) {
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/* With this lock, we prevent the other cpu to exit and enter
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* this function again and become the master */
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if (!spin_trylock(&master_lock))
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goto wfi;
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/* decouple the gic from the A9 cores */
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if (prcmu_gic_decouple()) {
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spin_unlock(&master_lock);
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goto out;
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}
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/* If an error occur, we will have to recouple the gic
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* manually */
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recouple = true;
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/* At this state, as the gic is decoupled, if the other
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* cpu is in WFI, we have the guarantee it won't be wake
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* up, so we can safely go to retention */
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if (!prcmu_is_cpu_in_wfi(this_cpu ? 0 : 1))
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goto out;
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/* The prcmu will be in charge of watching the interrupts
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* and wake up the cpus */
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if (prcmu_copy_gic_settings())
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goto out;
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/* Check in the meantime an interrupt did
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* not occur on the gic ... */
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if (prcmu_gic_pending_irq())
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goto out;
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/* ... and the prcmu */
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if (prcmu_pending_irq())
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goto out;
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/* Go to the retention state, the prcmu will wait for the
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* cpu to go WFI and this is what happens after exiting this
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* 'master' critical section */
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if (prcmu_set_power_state(PRCMU_AP_IDLE, true, true))
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goto out;
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/* When we switch to retention, the prcmu is in charge
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* of recoupling the gic automatically */
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recouple = false;
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spin_unlock(&master_lock);
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}
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wfi:
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cpu_do_idle();
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out:
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atomic_dec(&master);
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if (recouple) {
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prcmu_gic_recouple();
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spin_unlock(&master_lock);
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}
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return index;
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}
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static struct cpuidle_driver ux500_idle_driver = {
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.name = "ux500_idle",
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.owner = THIS_MODULE,
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.states = {
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ARM_CPUIDLE_WFI_STATE,
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{
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.enter = ux500_enter_idle,
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.exit_latency = 70,
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.target_residency = 260,
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.flags = CPUIDLE_FLAG_TIMER_STOP,
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.name = "ApIdle",
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.desc = "ARM Retention",
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},
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},
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.safe_state_index = 0,
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.state_count = 2,
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};
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static int dbx500_cpuidle_probe(struct platform_device *pdev)
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{
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/* Configure wake up reasons */
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prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) |
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PRCMU_WAKEUP(ABB));
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return cpuidle_register(&ux500_idle_driver, NULL);
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}
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static struct platform_driver dbx500_cpuidle_plat_driver = {
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.driver = {
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.name = "cpuidle-dbx500",
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.owner = THIS_MODULE,
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},
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.probe = dbx500_cpuidle_probe,
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};
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module_platform_driver(dbx500_cpuidle_plat_driver);
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