[RFC,1/8] RISC-V: Enable CPU_IDLE drivers

Message ID 20210221093758.210981-2-anup.patel@wdc.com
State Superseded
Headers show
Series
  • RISC-V CPU Idle Support
Related show

Commit Message

Anup Patel Feb. 21, 2021, 9:37 a.m.
We force select CPU_PM and provide asm/cpuidle.h so that we can
use CPU IDLE drivers for Linux RISC-V kernel.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
 arch/riscv/Kconfig                |  7 +++++++
 arch/riscv/configs/defconfig      |  7 +++----
 arch/riscv/configs/rv32_defconfig |  4 ++--
 arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
 arch/riscv/kernel/process.c       |  3 ++-
 5 files changed, 38 insertions(+), 7 deletions(-)
 create mode 100644 arch/riscv/include/asm/cpuidle.h

Comments

Alex Ghiti Feb. 26, 2021, 1:16 p.m. | #1
Hi Anup,

Le 2/21/21 à 4:37 AM, Anup Patel a écrit :
> We force select CPU_PM and provide asm/cpuidle.h so that we can
> use CPU IDLE drivers for Linux RISC-V kernel.
> 
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>   arch/riscv/Kconfig                |  7 +++++++
>   arch/riscv/configs/defconfig      |  7 +++----
>   arch/riscv/configs/rv32_defconfig |  4 ++--
>   arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
>   arch/riscv/kernel/process.c       |  3 ++-
>   5 files changed, 38 insertions(+), 7 deletions(-)
>   create mode 100644 arch/riscv/include/asm/cpuidle.h
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index fe6862b06ead..4901200b6b6c 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -37,6 +37,7 @@ config RISCV
>   	select CLONE_BACKWARDS
>   	select CLINT_TIMER if !MMU
>   	select COMMON_CLK
> +	select CPU_PM if CPU_IDLE
>   	select EDAC_SUPPORT
>   	select GENERIC_ARCH_TOPOLOGY if SMP
>   	select GENERIC_ATOMIC64 if !64BIT
> @@ -430,4 +431,10 @@ source "kernel/power/Kconfig"
>   
>   endmenu
>   
> +menu "CPU Power Management"
> +
> +source "drivers/cpuidle/Kconfig"
> +
> +endmenu
> +
>   source "drivers/firmware/Kconfig"
> diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
> index 6c0625aa96c7..dc4927c0e44b 100644
> --- a/arch/riscv/configs/defconfig
> +++ b/arch/riscv/configs/defconfig
> @@ -13,11 +13,13 @@ CONFIG_USER_NS=y
>   CONFIG_CHECKPOINT_RESTORE=y
>   CONFIG_BLK_DEV_INITRD=y
>   CONFIG_EXPERT=y
> +# CONFIG_SYSFS_SYSCALL is not set
>   CONFIG_BPF_SYSCALL=y
>   CONFIG_SOC_SIFIVE=y
>   CONFIG_SOC_VIRT=y
>   CONFIG_SMP=y
>   CONFIG_HOTPLUG_CPU=y
> +CONFIG_CPU_IDLE=y
>   CONFIG_JUMP_LABEL=y
>   CONFIG_MODULES=y
>   CONFIG_MODULE_UNLOAD=y
> @@ -65,10 +67,9 @@ CONFIG_HW_RANDOM=y
>   CONFIG_HW_RANDOM_VIRTIO=y
>   CONFIG_SPI=y
>   CONFIG_SPI_SIFIVE=y
> +# CONFIG_PTP_1588_CLOCK is not set
>   CONFIG_GPIOLIB=y
>   CONFIG_GPIO_SIFIVE=y
> -# CONFIG_PTP_1588_CLOCK is not set
> -CONFIG_POWER_RESET=y

Why do you remove this config ?

>   CONFIG_DRM=y
>   CONFIG_DRM_RADEON=y
>   CONFIG_DRM_VIRTIO_GPU=y
> @@ -132,5 +133,3 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y
>   # CONFIG_FTRACE is not set
>   # CONFIG_RUNTIME_TESTING_MENU is not set
>   CONFIG_MEMTEST=y
> -# CONFIG_SYSFS_SYSCALL is not set
> -CONFIG_EFI=y

And this is one too ? If those removals are intentional, maybe you can 
add something about that in the commit description ?

> diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> index 8dd02b842fef..332e43a4a2c3 100644
> --- a/arch/riscv/configs/rv32_defconfig
> +++ b/arch/riscv/configs/rv32_defconfig
> @@ -13,12 +13,14 @@ CONFIG_USER_NS=y
>   CONFIG_CHECKPOINT_RESTORE=y
>   CONFIG_BLK_DEV_INITRD=y
>   CONFIG_EXPERT=y
> +# CONFIG_SYSFS_SYSCALL is not set
>   CONFIG_BPF_SYSCALL=y
>   CONFIG_SOC_SIFIVE=y
>   CONFIG_SOC_VIRT=y
>   CONFIG_ARCH_RV32I=y
>   CONFIG_SMP=y
>   CONFIG_HOTPLUG_CPU=y
> +CONFIG_CPU_IDLE=y
>   CONFIG_JUMP_LABEL=y
>   CONFIG_MODULES=y
>   CONFIG_MODULE_UNLOAD=y
> @@ -67,7 +69,6 @@ CONFIG_HW_RANDOM_VIRTIO=y
>   CONFIG_SPI=y
>   CONFIG_SPI_SIFIVE=y
>   # CONFIG_PTP_1588_CLOCK is not set
> -CONFIG_POWER_RESET=y
>   CONFIG_DRM=y
>   CONFIG_DRM_RADEON=y
>   CONFIG_DRM_VIRTIO_GPU=y
> @@ -131,4 +132,3 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y
>   # CONFIG_FTRACE is not set
>   # CONFIG_RUNTIME_TESTING_MENU is not set
>   CONFIG_MEMTEST=y
> -# CONFIG_SYSFS_SYSCALL is not set
> diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h
> new file mode 100644
> index 000000000000..1042d790e446
> --- /dev/null
> +++ b/arch/riscv/include/asm/cpuidle.h
> @@ -0,0 +1,24 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2021 Allwinner Ltd
> + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> + */
> +
> +#ifndef _ASM_RISCV_CPUIDLE_H
> +#define _ASM_RISCV_CPUIDLE_H
> +
> +#include <asm/barrier.h>
> +#include <asm/processor.h>
> +
> +static inline void cpu_do_idle(void)
> +{
> +	/*
> +	 * Add mb() here to ensure that all
> +	 * IO/MEM access are completed prior

accessES ?

> +	 * to enter WFI.
> +	 */
> +	mb();
> +	wait_for_interrupt();
> +}
> +
> +#endif
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index dd5f985b1f40..b5b51fd26624 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -21,6 +21,7 @@
>   #include <asm/string.h>
>   #include <asm/switch_to.h>
>   #include <asm/thread_info.h>
> +#include <asm/cpuidle.h>
>   
>   register unsigned long gp_in_global __asm__("gp");
>   
> @@ -35,7 +36,7 @@ extern asmlinkage void ret_from_kernel_thread(void);
>   
>   void arch_cpu_idle(void)
>   {
> -	wait_for_interrupt();
> +	cpu_do_idle();
>   	raw_local_irq_enable();
>   }
>   
>
Anup Patel March 2, 2021, 6:42 a.m. | #2
On Fri, Feb 26, 2021 at 6:46 PM Alex Ghiti <alex@ghiti.fr> wrote:
>

> Hi Anup,

>

> Le 2/21/21 à 4:37 AM, Anup Patel a écrit :

> > We force select CPU_PM and provide asm/cpuidle.h so that we can

> > use CPU IDLE drivers for Linux RISC-V kernel.

> >

> > Signed-off-by: Anup Patel <anup.patel@wdc.com>

> > ---

> >   arch/riscv/Kconfig                |  7 +++++++

> >   arch/riscv/configs/defconfig      |  7 +++----

> >   arch/riscv/configs/rv32_defconfig |  4 ++--

> >   arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++

> >   arch/riscv/kernel/process.c       |  3 ++-

> >   5 files changed, 38 insertions(+), 7 deletions(-)

> >   create mode 100644 arch/riscv/include/asm/cpuidle.h

> >

> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig

> > index fe6862b06ead..4901200b6b6c 100644

> > --- a/arch/riscv/Kconfig

> > +++ b/arch/riscv/Kconfig

> > @@ -37,6 +37,7 @@ config RISCV

> >       select CLONE_BACKWARDS

> >       select CLINT_TIMER if !MMU

> >       select COMMON_CLK

> > +     select CPU_PM if CPU_IDLE

> >       select EDAC_SUPPORT

> >       select GENERIC_ARCH_TOPOLOGY if SMP

> >       select GENERIC_ATOMIC64 if !64BIT

> > @@ -430,4 +431,10 @@ source "kernel/power/Kconfig"

> >

> >   endmenu

> >

> > +menu "CPU Power Management"

> > +

> > +source "drivers/cpuidle/Kconfig"

> > +

> > +endmenu

> > +

> >   source "drivers/firmware/Kconfig"

> > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig

> > index 6c0625aa96c7..dc4927c0e44b 100644

> > --- a/arch/riscv/configs/defconfig

> > +++ b/arch/riscv/configs/defconfig

> > @@ -13,11 +13,13 @@ CONFIG_USER_NS=y

> >   CONFIG_CHECKPOINT_RESTORE=y

> >   CONFIG_BLK_DEV_INITRD=y

> >   CONFIG_EXPERT=y

> > +# CONFIG_SYSFS_SYSCALL is not set

> >   CONFIG_BPF_SYSCALL=y

> >   CONFIG_SOC_SIFIVE=y

> >   CONFIG_SOC_VIRT=y

> >   CONFIG_SMP=y

> >   CONFIG_HOTPLUG_CPU=y

> > +CONFIG_CPU_IDLE=y

> >   CONFIG_JUMP_LABEL=y

> >   CONFIG_MODULES=y

> >   CONFIG_MODULE_UNLOAD=y

> > @@ -65,10 +67,9 @@ CONFIG_HW_RANDOM=y

> >   CONFIG_HW_RANDOM_VIRTIO=y

> >   CONFIG_SPI=y

> >   CONFIG_SPI_SIFIVE=y

> > +# CONFIG_PTP_1588_CLOCK is not set

> >   CONFIG_GPIOLIB=y

> >   CONFIG_GPIO_SIFIVE=y

> > -# CONFIG_PTP_1588_CLOCK is not set

> > -CONFIG_POWER_RESET=y

>

> Why do you remove this config ?


This option is selected by CONFIG_SOC_VIRT so it is being
removed from defconfig by savedefconfig.

>

> >   CONFIG_DRM=y

> >   CONFIG_DRM_RADEON=y

> >   CONFIG_DRM_VIRTIO_GPU=y

> > @@ -132,5 +133,3 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y

> >   # CONFIG_FTRACE is not set

> >   # CONFIG_RUNTIME_TESTING_MENU is not set

> >   CONFIG_MEMTEST=y

> > -# CONFIG_SYSFS_SYSCALL is not set

> > -CONFIG_EFI=y

>

> And this is one too ? If those removals are intentional, maybe you can

> add something about that in the commit description ?


This is enabled by default so savedefconfig removes it.

>

> > diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig

> > index 8dd02b842fef..332e43a4a2c3 100644

> > --- a/arch/riscv/configs/rv32_defconfig

> > +++ b/arch/riscv/configs/rv32_defconfig

> > @@ -13,12 +13,14 @@ CONFIG_USER_NS=y

> >   CONFIG_CHECKPOINT_RESTORE=y

> >   CONFIG_BLK_DEV_INITRD=y

> >   CONFIG_EXPERT=y

> > +# CONFIG_SYSFS_SYSCALL is not set

> >   CONFIG_BPF_SYSCALL=y

> >   CONFIG_SOC_SIFIVE=y

> >   CONFIG_SOC_VIRT=y

> >   CONFIG_ARCH_RV32I=y

> >   CONFIG_SMP=y

> >   CONFIG_HOTPLUG_CPU=y

> > +CONFIG_CPU_IDLE=y

> >   CONFIG_JUMP_LABEL=y

> >   CONFIG_MODULES=y

> >   CONFIG_MODULE_UNLOAD=y

> > @@ -67,7 +69,6 @@ CONFIG_HW_RANDOM_VIRTIO=y

> >   CONFIG_SPI=y

> >   CONFIG_SPI_SIFIVE=y

> >   # CONFIG_PTP_1588_CLOCK is not set

> > -CONFIG_POWER_RESET=y

> >   CONFIG_DRM=y

> >   CONFIG_DRM_RADEON=y

> >   CONFIG_DRM_VIRTIO_GPU=y

> > @@ -131,4 +132,3 @@ CONFIG_DEBUG_BLOCK_EXT_DEVT=y

> >   # CONFIG_FTRACE is not set

> >   # CONFIG_RUNTIME_TESTING_MENU is not set

> >   CONFIG_MEMTEST=y

> > -# CONFIG_SYSFS_SYSCALL is not set

> > diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h

> > new file mode 100644

> > index 000000000000..1042d790e446

> > --- /dev/null

> > +++ b/arch/riscv/include/asm/cpuidle.h

> > @@ -0,0 +1,24 @@

> > +/* SPDX-License-Identifier: GPL-2.0 */

> > +/*

> > + * Copyright (C) 2021 Allwinner Ltd

> > + * Copyright (C) 2021 Western Digital Corporation or its affiliates.

> > + */

> > +

> > +#ifndef _ASM_RISCV_CPUIDLE_H

> > +#define _ASM_RISCV_CPUIDLE_H

> > +

> > +#include <asm/barrier.h>

> > +#include <asm/processor.h>

> > +

> > +static inline void cpu_do_idle(void)

> > +{

> > +     /*

> > +      * Add mb() here to ensure that all

> > +      * IO/MEM access are completed prior

>

> accessES ?

>

> > +      * to enter WFI.

> > +      */

> > +     mb();

> > +     wait_for_interrupt();

> > +}

> > +

> > +#endif

> > diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c

> > index dd5f985b1f40..b5b51fd26624 100644

> > --- a/arch/riscv/kernel/process.c

> > +++ b/arch/riscv/kernel/process.c

> > @@ -21,6 +21,7 @@

> >   #include <asm/string.h>

> >   #include <asm/switch_to.h>

> >   #include <asm/thread_info.h>

> > +#include <asm/cpuidle.h>

> >

> >   register unsigned long gp_in_global __asm__("gp");

> >

> > @@ -35,7 +36,7 @@ extern asmlinkage void ret_from_kernel_thread(void);

> >

> >   void arch_cpu_idle(void)

> >   {

> > -     wait_for_interrupt();

> > +     cpu_do_idle();

> >       raw_local_irq_enable();

> >   }

> >

> >


Regards,
Anup

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index fe6862b06ead..4901200b6b6c 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -37,6 +37,7 @@  config RISCV
 	select CLONE_BACKWARDS
 	select CLINT_TIMER if !MMU
 	select COMMON_CLK
+	select CPU_PM if CPU_IDLE
 	select EDAC_SUPPORT
 	select GENERIC_ARCH_TOPOLOGY if SMP
 	select GENERIC_ATOMIC64 if !64BIT
@@ -430,4 +431,10 @@  source "kernel/power/Kconfig"
 
 endmenu
 
+menu "CPU Power Management"
+
+source "drivers/cpuidle/Kconfig"
+
+endmenu
+
 source "drivers/firmware/Kconfig"
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index 6c0625aa96c7..dc4927c0e44b 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -13,11 +13,13 @@  CONFIG_USER_NS=y
 CONFIG_CHECKPOINT_RESTORE=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
+# CONFIG_SYSFS_SYSCALL is not set
 CONFIG_BPF_SYSCALL=y
 CONFIG_SOC_SIFIVE=y
 CONFIG_SOC_VIRT=y
 CONFIG_SMP=y
 CONFIG_HOTPLUG_CPU=y
+CONFIG_CPU_IDLE=y
 CONFIG_JUMP_LABEL=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
@@ -65,10 +67,9 @@  CONFIG_HW_RANDOM=y
 CONFIG_HW_RANDOM_VIRTIO=y
 CONFIG_SPI=y
 CONFIG_SPI_SIFIVE=y
+# CONFIG_PTP_1588_CLOCK is not set
 CONFIG_GPIOLIB=y
 CONFIG_GPIO_SIFIVE=y
-# CONFIG_PTP_1588_CLOCK is not set
-CONFIG_POWER_RESET=y
 CONFIG_DRM=y
 CONFIG_DRM_RADEON=y
 CONFIG_DRM_VIRTIO_GPU=y
@@ -132,5 +133,3 @@  CONFIG_DEBUG_BLOCK_EXT_DEVT=y
 # CONFIG_FTRACE is not set
 # CONFIG_RUNTIME_TESTING_MENU is not set
 CONFIG_MEMTEST=y
-# CONFIG_SYSFS_SYSCALL is not set
-CONFIG_EFI=y
diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
index 8dd02b842fef..332e43a4a2c3 100644
--- a/arch/riscv/configs/rv32_defconfig
+++ b/arch/riscv/configs/rv32_defconfig
@@ -13,12 +13,14 @@  CONFIG_USER_NS=y
 CONFIG_CHECKPOINT_RESTORE=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
+# CONFIG_SYSFS_SYSCALL is not set
 CONFIG_BPF_SYSCALL=y
 CONFIG_SOC_SIFIVE=y
 CONFIG_SOC_VIRT=y
 CONFIG_ARCH_RV32I=y
 CONFIG_SMP=y
 CONFIG_HOTPLUG_CPU=y
+CONFIG_CPU_IDLE=y
 CONFIG_JUMP_LABEL=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
@@ -67,7 +69,6 @@  CONFIG_HW_RANDOM_VIRTIO=y
 CONFIG_SPI=y
 CONFIG_SPI_SIFIVE=y
 # CONFIG_PTP_1588_CLOCK is not set
-CONFIG_POWER_RESET=y
 CONFIG_DRM=y
 CONFIG_DRM_RADEON=y
 CONFIG_DRM_VIRTIO_GPU=y
@@ -131,4 +132,3 @@  CONFIG_DEBUG_BLOCK_EXT_DEVT=y
 # CONFIG_FTRACE is not set
 # CONFIG_RUNTIME_TESTING_MENU is not set
 CONFIG_MEMTEST=y
-# CONFIG_SYSFS_SYSCALL is not set
diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h
new file mode 100644
index 000000000000..1042d790e446
--- /dev/null
+++ b/arch/riscv/include/asm/cpuidle.h
@@ -0,0 +1,24 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2021 Allwinner Ltd
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ */
+
+#ifndef _ASM_RISCV_CPUIDLE_H
+#define _ASM_RISCV_CPUIDLE_H
+
+#include <asm/barrier.h>
+#include <asm/processor.h>
+
+static inline void cpu_do_idle(void)
+{
+	/*
+	 * Add mb() here to ensure that all
+	 * IO/MEM access are completed prior
+	 * to enter WFI.
+	 */
+	mb();
+	wait_for_interrupt();
+}
+
+#endif
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index dd5f985b1f40..b5b51fd26624 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -21,6 +21,7 @@ 
 #include <asm/string.h>
 #include <asm/switch_to.h>
 #include <asm/thread_info.h>
+#include <asm/cpuidle.h>
 
 register unsigned long gp_in_global __asm__("gp");
 
@@ -35,7 +36,7 @@  extern asmlinkage void ret_from_kernel_thread(void);
 
 void arch_cpu_idle(void)
 {
-	wait_for_interrupt();
+	cpu_do_idle();
 	raw_local_irq_enable();
 }