| Message ID | 20220210054947.170134-2-apatel@ventanamicro.com |
|---|---|
| State | New |
| Headers | show |
| Series | RISC-V CPU Idle Support | expand |
Hi! > From: Anup Patel <anup.patel@wdc.com> > > 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> > Signed-off-by: Anup Patel <apatel@vetanamicro.com> This is quite... interesting. Normally we have one signoff per person... Best regards, Pavel
On Sat, Feb 12, 2022 at 5:13 PM Pavel Machek <pavel@ucw.cz> wrote: > > Hi! > > > From: Anup Patel <anup.patel@wdc.com> > > > > 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> > > Signed-off-by: Anup Patel <apatel@vetanamicro.com> > > This is quite... interesting. Normally we have one signoff per > person... I was working for Western Digital (WDC) when I first submitted this series and recently I joined Ventana Micro Systems. Regards, Anup > > Best regards, > Pavel > -- > http://www.livejournal.com/~pavelmachek
On Wed, Feb 9, 2022 at 9:50 PM Anup Patel <apatel@ventanamicro.com> wrote: > > From: Anup Patel <anup.patel@wdc.com> > > 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> > Signed-off-by: Anup Patel <apatel@vetanamicro.com> > Reviewed-by: Guo Ren <guoren@kernel.org> > --- > 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 5adcbd9b5e88..76976d12b463 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 > @@ -547,4 +548,10 @@ source "kernel/power/Kconfig" > > endmenu > > +menu "CPU Power Management" > + > +source "drivers/cpuidle/Kconfig" > + > +endmenu > + > source "arch/riscv/kvm/Kconfig" > diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig > index f120fcc43d0a..a5e0482a4969 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=m > CONFIG_JUMP_LABEL=y > diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig > index 8b56a7f1eb06..d1b87db54d68 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=m > 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(); > } > > -- > 2.25.1 > Reviewed-by: Atish Patra <atishp@rivosinc.com>
On Sat, 12 Feb 2022 04:49:46 PST (-0800), apatel@ventanamicro.com wrote: > On Sat, Feb 12, 2022 at 5:13 PM Pavel Machek <pavel@ucw.cz> wrote: >> >> Hi! >> >> > From: Anup Patel <anup.patel@wdc.com> >> > >> > 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> >> > Signed-off-by: Anup Patel <apatel@vetanamicro.com> >> >> This is quite... interesting. Normally we have one signoff per >> person... > > I was working for Western Digital (WDC) when I first submitted this > series and recently I joined Ventana Micro Systems. IIUC that's the correct way to go about this, it's certainly what I'd do. > > Regards, > Anup > >> >> Best regards, >> Pavel >> -- >> http://www.livejournal.com/~pavelmachek
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 5adcbd9b5e88..76976d12b463 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 @@ -547,4 +548,10 @@ source "kernel/power/Kconfig" endmenu +menu "CPU Power Management" + +source "drivers/cpuidle/Kconfig" + +endmenu + source "arch/riscv/kvm/Kconfig" diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig index f120fcc43d0a..a5e0482a4969 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=m CONFIG_JUMP_LABEL=y diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig index 8b56a7f1eb06..d1b87db54d68 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=m 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(); }