diff mbox series

[v8,1/8] RISC-V: Enable CPU_IDLE drivers

Message ID 20211011081820.1135261-2-anup.patel@wdc.com (mailing list archive)
State New, archived
Headers show
Series RISC-V CPU Idle Support | expand

Commit Message

Anup Patel Oct. 11, 2021, 8:18 a.m. UTC
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      |  1 +
 arch/riscv/configs/rv32_defconfig |  1 +
 arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
 arch/riscv/kernel/process.c       |  3 ++-
 5 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 arch/riscv/include/asm/cpuidle.h

Comments

Heiko Stuebner Oct. 11, 2021, 10:04 p.m. UTC | #1
Hi Anup,

Am Montag, 11. Oktober 2021, 10:18:13 CEST schrieb Anup Patel:
> 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      |  1 +
>  arch/riscv/configs/rv32_defconfig |  1 +
>  arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
>  arch/riscv/kernel/process.c       |  3 ++-
>  5 files changed, 35 insertions(+), 1 deletion(-)
>  create mode 100644 arch/riscv/include/asm/cpuidle.h
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 8de2afb460f7..d02f1f5a2431 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -46,6 +46,7 @@ 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
> @@ -564,5 +565,11 @@ source "kernel/power/Kconfig"
>  
>  endmenu
>  
> +menu "CPU Power Management"
> +
> +source "drivers/cpuidle/Kconfig"
> +
> +endmenu
> +
>  source "arch/riscv/kvm/Kconfig"
>  source "drivers/firmware/Kconfig"
> diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
> index be21f54e9b91..39b4c32e7997 100644
> --- a/arch/riscv/configs/defconfig
> +++ b/arch/riscv/configs/defconfig
> @@ -20,6 +20,7 @@ CONFIG_SOC_SIFIVE=y
>  CONFIG_SOC_VIRT=y
>  CONFIG_SMP=y
>  CONFIG_HOTPLUG_CPU=y
> +CONFIG_CPU_IDLE=y
>  CONFIG_VIRTUALIZATION=y
>  CONFIG_KVM=y
>  CONFIG_JUMP_LABEL=y

This doesn't apply.

In the history of your tree that you referenced in the cover-letter
I found "RISC-V: Enable KVM for RV64 and RV32"
with that nice "DO NOT UPSTREAM !!!!!" message in caps in it ;-)

This of course makes this not apply on the main riscv tree.

So you might want to base your series on top of a clean "for-next"
branch of Palmer's tree instead of collecting other stuff below it.

Same for rv32_defconfig below.


Heiko


> diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> index ad01f50c98f1..fed827c82a9e 100644
> --- a/arch/riscv/configs/rv32_defconfig
> +++ b/arch/riscv/configs/rv32_defconfig
> @@ -20,6 +20,7 @@ CONFIG_SOC_VIRT=y
>  CONFIG_ARCH_RV32I=y
>  CONFIG_SMP=y
>  CONFIG_HOTPLUG_CPU=y
> +CONFIG_CPU_IDLE=y
>  CONFIG_VIRTUALIZATION=y
>  CONFIG_KVM=y
>  CONFIG_JUMP_LABEL=y
> diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h
> new file mode 100644
> index 000000000000..71fdc607d4bc
> --- /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 accesses are completed prior
> +	 * to entering WFI.
> +	 */
> +	mb();
> +	wait_for_interrupt();
> +}
> +
> +#endif
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index 03ac3aa611f5..504b496787aa 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -23,6 +23,7 @@
>  #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");
>  
> @@ -37,7 +38,7 @@ extern asmlinkage void ret_from_kernel_thread(void);
>  
>  void arch_cpu_idle(void)
>  {
> -	wait_for_interrupt();
> +	cpu_do_idle();
>  	raw_local_irq_enable();
>  }
>  
>
Heiko Stuebner Oct. 11, 2021, 11:16 p.m. UTC | #2
Hi Anup,

Am Montag, 11. Oktober 2021, 10:18:13 CEST schrieb Anup Patel:
> 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      |  1 +
>  arch/riscv/configs/rv32_defconfig |  1 +
>  arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
>  arch/riscv/kernel/process.c       |  3 ++-
>  5 files changed, 35 insertions(+), 1 deletion(-)
>  create mode 100644 arch/riscv/include/asm/cpuidle.h
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 8de2afb460f7..d02f1f5a2431 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -46,6 +46,7 @@ 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
> @@ -564,5 +565,11 @@ source "kernel/power/Kconfig"
>  
>  endmenu
>  
> +menu "CPU Power Management"
> +
> +source "drivers/cpuidle/Kconfig"
> +
> +endmenu
> +
>  source "arch/riscv/kvm/Kconfig"
>  source "drivers/firmware/Kconfig"

another issue, the "arch/riscv/kvm/Kconfig" line above comes from a
commit that is not in the riscv-tree at all but in the kvm-tree [0],
making this patch fail to apply onto riscv/for-next alone.

If you have multiple independent patch series in flight, like shown in
the github branch you references, it might be easier to base each on
top of the relevant branch cleanly and after one gets applied rebase
the other ones.

That way you're not dependent on the others going in first and also
people can test patch series individually without too much hassle.

Thanks
Heiko


[0] https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git/commit/?h=next&id=99cdc6c18c2d815e940e81b9b477d469bdd41788
Anup Patel Oct. 12, 2021, 12:54 a.m. UTC | #3
On Tue, Oct 12, 2021 at 3:34 AM Heiko Stübner <heiko@sntech.de> wrote:
>
> Hi Anup,
>
> Am Montag, 11. Oktober 2021, 10:18:13 CEST schrieb Anup Patel:
> > 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      |  1 +
> >  arch/riscv/configs/rv32_defconfig |  1 +
> >  arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
> >  arch/riscv/kernel/process.c       |  3 ++-
> >  5 files changed, 35 insertions(+), 1 deletion(-)
> >  create mode 100644 arch/riscv/include/asm/cpuidle.h
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index 8de2afb460f7..d02f1f5a2431 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -46,6 +46,7 @@ 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
> > @@ -564,5 +565,11 @@ source "kernel/power/Kconfig"
> >
> >  endmenu
> >
> > +menu "CPU Power Management"
> > +
> > +source "drivers/cpuidle/Kconfig"
> > +
> > +endmenu
> > +
> >  source "arch/riscv/kvm/Kconfig"
> >  source "drivers/firmware/Kconfig"
> > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
> > index be21f54e9b91..39b4c32e7997 100644
> > --- a/arch/riscv/configs/defconfig
> > +++ b/arch/riscv/configs/defconfig
> > @@ -20,6 +20,7 @@ CONFIG_SOC_SIFIVE=y
> >  CONFIG_SOC_VIRT=y
> >  CONFIG_SMP=y
> >  CONFIG_HOTPLUG_CPU=y
> > +CONFIG_CPU_IDLE=y
> >  CONFIG_VIRTUALIZATION=y
> >  CONFIG_KVM=y
> >  CONFIG_JUMP_LABEL=y
>
> This doesn't apply.
>
> In the history of your tree that you referenced in the cover-letter
> I found "RISC-V: Enable KVM for RV64 and RV32"
> with that nice "DO NOT UPSTREAM !!!!!" message in caps in it ;-)
>
> This of course makes this not apply on the main riscv tree.
>
> So you might want to base your series on top of a clean "for-next"
> branch of Palmer's tree instead of collecting other stuff below it.

I usually base everything on the most recent Linus release tag.

This time I accidentally rebased on my KVM RISC-V branch which
was merged recently.

I will anyway send v9.

Regards,
Anup

>
> Same for rv32_defconfig below.
>
>
> Heiko
>
>
> > diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
> > index ad01f50c98f1..fed827c82a9e 100644
> > --- a/arch/riscv/configs/rv32_defconfig
> > +++ b/arch/riscv/configs/rv32_defconfig
> > @@ -20,6 +20,7 @@ CONFIG_SOC_VIRT=y
> >  CONFIG_ARCH_RV32I=y
> >  CONFIG_SMP=y
> >  CONFIG_HOTPLUG_CPU=y
> > +CONFIG_CPU_IDLE=y
> >  CONFIG_VIRTUALIZATION=y
> >  CONFIG_KVM=y
> >  CONFIG_JUMP_LABEL=y
> > diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h
> > new file mode 100644
> > index 000000000000..71fdc607d4bc
> > --- /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 accesses are completed prior
> > +      * to entering WFI.
> > +      */
> > +     mb();
> > +     wait_for_interrupt();
> > +}
> > +
> > +#endif
> > diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> > index 03ac3aa611f5..504b496787aa 100644
> > --- a/arch/riscv/kernel/process.c
> > +++ b/arch/riscv/kernel/process.c
> > @@ -23,6 +23,7 @@
> >  #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");
> >
> > @@ -37,7 +38,7 @@ 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 Oct. 12, 2021, 12:57 a.m. UTC | #4
On Tue, Oct 12, 2021 at 4:46 AM Heiko Stübner <heiko@sntech.de> wrote:
>
> Hi Anup,
>
> Am Montag, 11. Oktober 2021, 10:18:13 CEST schrieb Anup Patel:
> > 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      |  1 +
> >  arch/riscv/configs/rv32_defconfig |  1 +
> >  arch/riscv/include/asm/cpuidle.h  | 24 ++++++++++++++++++++++++
> >  arch/riscv/kernel/process.c       |  3 ++-
> >  5 files changed, 35 insertions(+), 1 deletion(-)
> >  create mode 100644 arch/riscv/include/asm/cpuidle.h
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index 8de2afb460f7..d02f1f5a2431 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -46,6 +46,7 @@ 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
> > @@ -564,5 +565,11 @@ source "kernel/power/Kconfig"
> >
> >  endmenu
> >
> > +menu "CPU Power Management"
> > +
> > +source "drivers/cpuidle/Kconfig"
> > +
> > +endmenu
> > +
> >  source "arch/riscv/kvm/Kconfig"
> >  source "drivers/firmware/Kconfig"
>
> another issue, the "arch/riscv/kvm/Kconfig" line above comes from a
> commit that is not in the riscv-tree at all but in the kvm-tree [0],
> making this patch fail to apply onto riscv/for-next alone.
>
> If you have multiple independent patch series in flight, like shown in
> the github branch you references, it might be easier to base each on
> top of the relevant branch cleanly and after one gets applied rebase
> the other ones.

I know I have been doing that but this time accidently picked the wrong
branch to rebase upon.

Thanks for trying.

Regards,
Anup

>
> That way you're not dependent on the others going in first and also
> people can test patch series individually without too much hassle.
>
> Thanks
> Heiko
>
>
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git/commit/?h=next&id=99cdc6c18c2d815e940e81b9b477d469bdd41788
>
>
diff mbox series

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 8de2afb460f7..d02f1f5a2431 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -46,6 +46,7 @@  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
@@ -564,5 +565,11 @@  source "kernel/power/Kconfig"
 
 endmenu
 
+menu "CPU Power Management"
+
+source "drivers/cpuidle/Kconfig"
+
+endmenu
+
 source "arch/riscv/kvm/Kconfig"
 source "drivers/firmware/Kconfig"
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index be21f54e9b91..39b4c32e7997 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -20,6 +20,7 @@  CONFIG_SOC_SIFIVE=y
 CONFIG_SOC_VIRT=y
 CONFIG_SMP=y
 CONFIG_HOTPLUG_CPU=y
+CONFIG_CPU_IDLE=y
 CONFIG_VIRTUALIZATION=y
 CONFIG_KVM=y
 CONFIG_JUMP_LABEL=y
diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
index ad01f50c98f1..fed827c82a9e 100644
--- a/arch/riscv/configs/rv32_defconfig
+++ b/arch/riscv/configs/rv32_defconfig
@@ -20,6 +20,7 @@  CONFIG_SOC_VIRT=y
 CONFIG_ARCH_RV32I=y
 CONFIG_SMP=y
 CONFIG_HOTPLUG_CPU=y
+CONFIG_CPU_IDLE=y
 CONFIG_VIRTUALIZATION=y
 CONFIG_KVM=y
 CONFIG_JUMP_LABEL=y
diff --git a/arch/riscv/include/asm/cpuidle.h b/arch/riscv/include/asm/cpuidle.h
new file mode 100644
index 000000000000..71fdc607d4bc
--- /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 accesses are completed prior
+	 * to entering WFI.
+	 */
+	mb();
+	wait_for_interrupt();
+}
+
+#endif
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 03ac3aa611f5..504b496787aa 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -23,6 +23,7 @@ 
 #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");
 
@@ -37,7 +38,7 @@  extern asmlinkage void ret_from_kernel_thread(void);
 
 void arch_cpu_idle(void)
 {
-	wait_for_interrupt();
+	cpu_do_idle();
 	raw_local_irq_enable();
 }