Re: [PATCH 5/6] ARM: psci: cpuidle: Enable PSCI CPUidle driver

[Sudeep Holla]

On Mon, Jul 22, 2019 at 04:37:44PM +0100, Lorenzo Pieralisi wrote:
> Allow selection of the PSCI CPUidle in the kernel by adding
> the required Kconfig options.
> 
> Remove PSCI callbacks from ARM/ARM64 generic CPU ops
> to prevent the PSCI idle driver from clashing with the generic
> ARM CPUidle driver initialization, that relies on CPU ops
> to initialize and enter idle states.
> 
> Update the affected defconfig files to guarantee seamingless
> transition from the generic ARM CPUidle to the PSCI CPUidle
> driver on arch/platforms using it.
> 
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
> Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> ---
>  arch/arm/configs/imx_v6_v7_defconfig | 1 +
>  arch/arm64/configs/defconfig         | 1 +

Better to keep above you as separate patch, though it may cause
minor issues from bisectibility. It may be needed anyway for merging.

>  arch/arm64/kernel/cpuidle.c          | 7 ++++---
>  arch/arm64/kernel/psci.c             | 4 ----
>  drivers/cpuidle/Kconfig.arm          | 8 ++++++--
>  drivers/firmware/psci/psci.c         | 9 ---------
>  6 files changed, 12 insertions(+), 18 deletions(-)
> 
> diff --git a/arch/arm/configs/imx_v6_v7_defconfig b/arch/arm/configs/imx_v6_v7_defconfig
> index a53b29251ed4..4174fd1b79e7 100644
> --- a/arch/arm/configs/imx_v6_v7_defconfig
> +++ b/arch/arm/configs/imx_v6_v7_defconfig
> @@ -60,6 +60,7 @@ CONFIG_ARM_IMX6Q_CPUFREQ=y
>  CONFIG_ARM_IMX_CPUFREQ_DT=y
>  CONFIG_CPU_IDLE=y
>  CONFIG_ARM_CPUIDLE=y
> +CONFIG_ARM_PSCI_CPUIDLE=y
>  CONFIG_VFP=y
>  CONFIG_NEON=y
>  CONFIG_PM_DEBUG=y
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 0e58ef02880c..c0a7cfe3aebd 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -72,6 +72,7 @@ CONFIG_RANDOMIZE_BASE=y
>  CONFIG_HIBERNATION=y
>  CONFIG_WQ_POWER_EFFICIENT_DEFAULT=y
>  CONFIG_ARM_CPUIDLE=y
> +CONFIG_ARM_PSCI_CPUIDLE=y
>  CONFIG_CPU_FREQ=y
>  CONFIG_CPU_FREQ_STAT=y
>  CONFIG_CPU_FREQ_GOV_POWERSAVE=m
> diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c
> index d1048173fd8a..4bcd1bca0dfc 100644
> --- a/arch/arm64/kernel/cpuidle.c
> +++ b/arch/arm64/kernel/cpuidle.c
> @@ -11,6 +11,7 @@
>  #include <linux/cpu_pm.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
> +#include <linux/psci.h>
>  
>  #include <asm/cpuidle.h>
>  #include <asm/cpu_ops.h>
> @@ -48,15 +49,15 @@ int arm_cpuidle_suspend(int index)
>  
>  int acpi_processor_ffh_lpi_probe(unsigned int cpu)
>  {
> -	return arm_cpuidle_init(cpu);
> +	return psci_acpi_cpu_init_idle(cpu);

This will break build as psci_acpi_cpu_init_idle is introduced in next patch.
You can simply move it to next patch I assume.

>  }
>  
>  int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
>  {
>  	if (ARM64_LPI_IS_RETENTION_STATE(lpi->arch_flags))
> -		return CPU_PM_CPU_IDLE_ENTER_RETENTION(arm_cpuidle_suspend,
> +		return CPU_PM_CPU_IDLE_ENTER_RETENTION(psci_cpu_suspend_enter,
>  						lpi->index);
>  	else
> -		return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index);
> +		return CPU_PM_CPU_IDLE_ENTER(psci_cpu_suspend_enter, lpi->index);
>  }
>  #endif
> diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
> index 85ee7d07889e..a543ab7e007c 100644
> --- a/arch/arm64/kernel/psci.c
> +++ b/arch/arm64/kernel/psci.c
> @@ -105,10 +105,6 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
>  
>  const struct cpu_operations cpu_psci_ops = {
>  	.name		= "psci",
> -#ifdef CONFIG_CPU_IDLE
> -	.cpu_init_idle	= psci_cpu_init_idle,
> -	.cpu_suspend	= psci_cpu_suspend_enter,
> -#endif
>  	.cpu_init	= cpu_psci_cpu_init,
>  	.cpu_prepare	= cpu_psci_cpu_prepare,
>  	.cpu_boot	= cpu_psci_cpu_boot,
> diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
> index 929b57424ea4..b9c56c60ab98 100644
> --- a/drivers/cpuidle/Kconfig.arm
> +++ b/drivers/cpuidle/Kconfig.arm
> @@ -14,8 +14,12 @@ config ARM_CPUIDLE
>            provided by architecture code.
>  
>  config ARM_PSCI_CPUIDLE
> -	bool
> -
> +	bool "PSCI CPU idle Driver"

As mentioned in previous patch, do you see issues having just above
change in this patch and the below ones moved to the previous.

> +	depends on ARM_PSCI_FW
> +	select DT_IDLE_STATES
> +	select CPU_IDLE_MULTIPLE_DRIVERS
> +	help
> +	  Select this to enable PSCI firmware based CPUidle driver for ARM.

You need extra blank line here.

--
Regards,
Sudeep