Commit a5e0454c authored by Ulf Hansson's avatar Ulf Hansson
Browse files

cpuidle: psci: Add a helper to attach a CPU to its PM domain 



Introduce a PSCI DT helper function, psci_dt_attach_cpu(), which takes a
CPU number as an in-parameter and tries to attach the CPU's struct device
to its corresponding PM domain.

Let's makes use of dev_pm_domain_attach_by_name(), as it allows us to
specify "psci" as the "name" of the PM domain to attach to. Additionally,
let's also prepare the attached device to be power managed via runtime PM.

Note that, the implementation of the new helper function is in a new
separate c-file, which may seems a bit too much at this point. However,
subsequent changes that implements the remaining part of the PM domain
support for cpuidle-psci, helps to justify this split.

Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: default avatarSudeep Holla <sudeep.holla@arm.com>
Acked-by: default avatarRafael J. Wysocki <rafael@kernel.org>
parent f08cfbfa

drivers/cpuidle/Makefile

+3 −1
Original line number Diff line number Diff line
@@ -21,7 +21,9 @@ obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o 
obj-$(CONFIG_ARM_AT91_CPUIDLE)          += cpuidle-at91.o

obj-$(CONFIG_ARM_EXYNOS_CPUIDLE)        += cpuidle-exynos.o

obj-$(CONFIG_ARM_CPUIDLE)		+= cpuidle-arm.o

obj-$(CONFIG_ARM_PSCI_CPUIDLE)		+= cpuidle-psci.o

obj-$(CONFIG_ARM_PSCI_CPUIDLE)		+= cpuidle_psci.o

cpuidle_psci-y				:= cpuidle-psci.o

cpuidle_psci-$(CONFIG_PM_GENERIC_DOMAINS_OF) += cpuidle-psci-domain.o



###############################################################################

# MIPS drivers

drivers/cpuidle/cpuidle-psci-domain.c

0 → 100644
+31 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * PM domains for CPUs via genpd - managed by cpuidle-psci.

 *

 * Copyright (C) 2019 Linaro Ltd.

 * Author: Ulf Hansson <ulf.hansson@linaro.org>

 *

 */



#include <linux/cpu.h>

#include <linux/device.h>

#include <linux/kernel.h>

#include <linux/pm_domain.h>

#include <linux/pm_runtime.h>



#include "cpuidle-psci.h"



struct device __init *psci_dt_attach_cpu(int cpu)

{

	struct device *dev;



	dev = dev_pm_domain_attach_by_name(get_cpu_device(cpu), "psci");

	if (IS_ERR_OR_NULL(dev))

		return dev;



	pm_runtime_irq_safe(dev);

	if (cpu_online(cpu))

		pm_runtime_get_sync(dev);



	return dev;

}

drivers/cpuidle/cpuidle-psci.h

0 → 100644
+12 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */



#ifndef __CPUIDLE_PSCI_H

#define __CPUIDLE_PSCI_H



#ifdef CONFIG_PM_GENERIC_DOMAINS_OF

struct device __init *psci_dt_attach_cpu(int cpu);

#else

static inline struct device __init *psci_dt_attach_cpu(int cpu) { return NULL; }

#endif



#endif /* __CPUIDLE_PSCI_H */

CRA Git | Maintained and supported by SUSTech CRA and CCSE