[PATCH v11 1/8] RISC-V: Enable CPU_IDLE drivers
From: Anup Patel <hidden>
Date: 2022-02-10 05:51:01
Also in:
kvm-riscv, linux-arm-kernel, linux-pm, linux-riscv, lkml
Subsystem:
risc-v architecture, the rest · Maintainers:
Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
From: Anup Patel <redacted> 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 <redacted> Signed-off-by: Anup Patel <redacted> 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