[PATCH v9 1/8] RISC-V: Enable CPU_IDLE drivers
Anup Patel
anup.patel at wdc.com
Tue Oct 12 02:58:50 PDT 2021
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 at wdc.com>
---
arch/riscv/Kconfig | 7 +++++++
arch/riscv/configs/defconfig | 14 ++++++--------
arch/riscv/configs/rv32_defconfig | 7 +++----
arch/riscv/include/asm/cpuidle.h | 24 ++++++++++++++++++++++++
arch/riscv/kernel/process.c | 3 ++-
5 files changed, 42 insertions(+), 13 deletions(-)
create mode 100644 arch/riscv/include/asm/cpuidle.h
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 3105e1beb980..7256ee3e8629 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
@@ -562,3 +563,9 @@ menu "Power management options"
source "kernel/power/Kconfig"
endmenu
+
+menu "CPU Power Management"
+
+source "drivers/cpuidle/Kconfig"
+
+endmenu
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index 4ebc80315f01..9851ba671e90 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -2,6 +2,7 @@ CONFIG_SYSVIPC=y
CONFIG_POSIX_MQUEUE=y
CONFIG_NO_HZ_IDLE=y
CONFIG_HIGH_RES_TIMERS=y
+CONFIG_BPF_SYSCALL=y
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y
CONFIG_CGROUPS=y
@@ -13,12 +14,13 @@ CONFIG_USER_NS=y
CONFIG_CHECKPOINT_RESTORE=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_EXPERT=y
-CONFIG_BPF_SYSCALL=y
+# CONFIG_SYSFS_SYSCALL is not set
+CONFIG_SOC_MICROCHIP_POLARFIRE=y
CONFIG_SOC_SIFIVE=y
CONFIG_SOC_VIRT=y
-CONFIG_SOC_MICROCHIP_POLARFIRE=y
CONFIG_SMP=y
CONFIG_HOTPLUG_CPU=y
+CONFIG_CPU_IDLE=y
CONFIG_JUMP_LABEL=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
@@ -68,14 +70,12 @@ 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
-CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_USB=y
CONFIG_USB_XHCI_HCD=y
CONFIG_USB_XHCI_PLATFORM=y
@@ -85,10 +85,10 @@ CONFIG_USB_OHCI_HCD=y
CONFIG_USB_OHCI_HCD_PLATFORM=y
CONFIG_USB_STORAGE=y
CONFIG_USB_UAS=y
+CONFIG_MMC=y
CONFIG_MMC_SDHCI=y
CONFIG_MMC_SDHCI_PLTFM=y
CONFIG_MMC_SDHCI_CADENCE=y
-CONFIG_MMC=y
CONFIG_MMC_SPI=y
CONFIG_RTC_CLASS=y
CONFIG_VIRTIO_PCI=y
@@ -139,5 +139,3 @@ CONFIG_RCU_EQS_DEBUG=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 434ef5b64599..725ca3332900 100644
--- a/arch/riscv/configs/rv32_defconfig
+++ b/arch/riscv/configs/rv32_defconfig
@@ -2,6 +2,7 @@ CONFIG_SYSVIPC=y
CONFIG_POSIX_MQUEUE=y
CONFIG_NO_HZ_IDLE=y
CONFIG_HIGH_RES_TIMERS=y
+CONFIG_BPF_SYSCALL=y
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y
CONFIG_CGROUPS=y
@@ -13,12 +14,13 @@ CONFIG_USER_NS=y
CONFIG_CHECKPOINT_RESTORE=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_EXPERT=y
-CONFIG_BPF_SYSCALL=y
+# CONFIG_SYSFS_SYSCALL is not set
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
@@ -67,11 +69,9 @@ 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
-CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_USB=y
CONFIG_USB_XHCI_HCD=y
CONFIG_USB_XHCI_PLATFORM=y
@@ -130,4 +130,3 @@ CONFIG_RCU_EQS_DEBUG=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..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
More information about the linux-riscv
mailing list