Re: [PATCH v2 2/2] arm: kernel: implement cpuidle_ops with psci backend

[Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>]

On Wed, Jul 08, 2015 at 01:51:08PM +0100, Jisheng Zhang wrote:
> This patch implements cpuidle_ops using psci. After this patch, we can
> use cpuidle-arm.c with psci backend for both arm and arm64.
> 
> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
>  arch/arm/kernel/Makefile       |  1 +
>  arch/arm/kernel/psci_cpuidle.c | 29 +++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+)
>  create mode 100644 arch/arm/kernel/psci_cpuidle.c
> 
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index 3b995f5..96383d8 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -91,6 +91,7 @@ obj-$(CONFIG_ARM_VIRT_EXT)	+= hyp-stub.o
>  ifeq ($(CONFIG_ARM_PSCI),y)
>  obj-y				+= psci-call.o
>  obj-$(CONFIG_SMP)		+= psci_smp.o
> +obj-$(CONFIG_CPU_IDLE)		+= psci_cpuidle.o
>  endif
>  
>  extra-y := $(head-y) vmlinux.lds
> diff --git a/arch/arm/kernel/psci_cpuidle.c b/arch/arm/kernel/psci_cpuidle.c
> new file mode 100644
> index 0000000..ae85d97
> --- /dev/null
> +++ b/arch/arm/kernel/psci_cpuidle.c
> @@ -0,0 +1,29 @@
> +/*
> + * Copyright (C) 2015 Marvell Technology Group Ltd.
> + * Author: Jisheng Zhang <jszhang@marvell.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/cpuidle.h>
> +#include <linux/psci.h>
> +
> +#include <asm/cpuidle.h>
> +
> +static int psci_cpuidle_suspend(int cpu, unsigned long arg)
> +{
> +	return cpu_psci_cpu_suspend(arg);
> +}
> +
> +static int psci_cpuidle_init(struct device_node *node, int cpu)
> +{
> +	return cpu_psci_cpu_init_idle(cpu);
> +}

It probably makes sense to change the prototypes now that there is
just one cpuidle ops merged for arm, better now than later.

I am not too fussed about leaving these shims, but I think this can
save us some time in the future.

Daniel what do you think ?

Lorenzo

> +
> +static struct cpuidle_ops psci_cpuidle_ops __initdata = {
> +	.suspend = psci_cpuidle_suspend,
> +	.init = psci_cpuidle_init,
> +};
> +CPUIDLE_METHOD_OF_DECLARE(psci_cpuidle, "psci", &psci_cpuidle_ops);
> -- 
> 2.1.4
>