[PATCH v11 0/8] RISC-V CPU Idle Support

Anup Patel
2022-02-10T05:50:48Z

From: Anup Patel <anup.patel@wdc.com>

This series adds RISC-V CPU Idle support using SBI HSM suspend function.
The RISC-V SBI CPU idle driver added by this series is highly inspired
from the ARM PSCI CPU idle driver.

At high-level, this series includes the following changes:
1) Preparatory arch/riscv patches (Patches 1 to 3)
2) Defines for RISC-V SBI HSM suspend (Patch 4)
3) Preparatory patch to share code between RISC-V SBI CPU idle driver
and ARM PSCI CPU idle driver (Patch 5)
4) RISC-V SBI CPU idle driver and related DT bindings (Patches 6 to 7)

These patches can be found in riscv_sbi_hsm_suspend_v11 branch of
https://github.com/avpatel/linux.git

Special thanks Sandeep Tripathy for providing early feeback on SBI HSM
support in all above projects (RISC-V SBI specification, OpenSBI, and
Linux RISC-V).

Changes since v10:
- Rebased on Linux-5.17-rc3
- Typo fix in commit description of PATCH6

Changes since v9:
- Rebased on Linux-5.17-rc1

Changes since v8:
- Rebased on Linux-5.15-rc5
- Fixed DT schema check errors in PATCH7

Changes since v7:
- Rebased on Linux-5.15-rc3
- Renamed cpuidle-sbi.c to cpuidle-riscv-sbi.c in PATCH6

Changes since v6:
- Fixed error reported by "make DT_CHECKER_FLAGS=-m dt_binding_check"

Changes since v5:
- Rebased on Linux-5.13-rc5
- Removed unnecessary exports from PATCH5
- Removed stray ";" from PATCH5
- Moved sbi_cpuidle_pd_power_off() under "#ifdef CONFIG_DT_IDLE_GENPD"
in PATCH6

Changes since v4:
- Rebased on Linux-5.13-rc2
- Renamed all dt_idle_genpd functions to have "dt_idle_" prefix
- Added MAINTAINERS file entry for dt_idle_genpd

Changes since v3:
- Rebased on Linux-5.13-rc2
- Fixed __cpu_resume_enter() which was broken due to XIP kernel support
- Removed "struct dt_idle_genpd_ops" abstraction which simplifies code
sharing between ARM PSCI and RISC-V SBI drivers in PATCH5

Changes since v2:
- Rebased on Linux-5.12-rc3
- Updated PATCH7 to add common DT bindings for both ARM and RISC-V
idle states
- Added "additionalProperties = false" for both idle-states node and
child nodes in PATCH7

Changes since v1:
- Fixex minor typo in PATCH1
- Use just "idle-states" as DT node name for CPU idle states
- Added documentation for "cpu-idle-states" DT property in
devicetree/bindings/riscv/cpus.yaml
- Added documentation for "riscv,sbi-suspend-param" DT property in
devicetree/bindings/riscv/idle-states.yaml

Anup Patel (8):
RISC-V: Enable CPU_IDLE drivers
RISC-V: Rename relocate() and make it global
RISC-V: Add arch functions for non-retentive suspend entry/exit
RISC-V: Add SBI HSM suspend related defines
cpuidle: Factor-out power domain related code from PSCI domain driver
cpuidle: Add RISC-V SBI CPU idle driver
dt-bindings: Add common bindings for ARM and RISC-V idle states
RISC-V: Enable RISC-V SBI CPU Idle driver for QEMU virt machine

.../bindings/arm/msm/qcom,idle-state.txt | 2 +-
.../devicetree/bindings/arm/psci.yaml | 2 +-
.../bindings/{arm => cpu}/idle-states.yaml | 228 ++++++-
.../devicetree/bindings/riscv/cpus.yaml | 6 +
MAINTAINERS | 14 +
arch/riscv/Kconfig | 7 +
arch/riscv/Kconfig.socs | 3 +
arch/riscv/configs/defconfig | 2 +
arch/riscv/configs/rv32_defconfig | 2 +
arch/riscv/include/asm/asm.h | 27 +
arch/riscv/include/asm/cpuidle.h | 24 +
arch/riscv/include/asm/sbi.h | 27 +-
arch/riscv/include/asm/suspend.h | 36 +
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/asm-offsets.c | 3 +
arch/riscv/kernel/cpu_ops_sbi.c | 2 +-
arch/riscv/kernel/head.S | 28 +-
arch/riscv/kernel/process.c | 3 +-
arch/riscv/kernel/suspend.c | 87 +++
arch/riscv/kernel/suspend_entry.S | 124 ++++
arch/riscv/kvm/vcpu_sbi_hsm.c | 4 +-
drivers/cpuidle/Kconfig | 9 +
drivers/cpuidle/Kconfig.arm | 1 +
drivers/cpuidle/Kconfig.riscv | 15 +
drivers/cpuidle/Makefile | 5 +
drivers/cpuidle/cpuidle-psci-domain.c | 138 +---
drivers/cpuidle/cpuidle-psci.h | 15 +-
drivers/cpuidle/cpuidle-riscv-sbi.c | 627 ++++++++++++++++++
drivers/cpuidle/dt_idle_genpd.c | 178 +++++
drivers/cpuidle/dt_idle_genpd.h | 50 ++
30 files changed, 1484 insertions(+), 187 deletions(-)
rename Documentation/devicetree/bindings/{arm => cpu}/idle-states.yaml (74%)
create mode 100644 arch/riscv/include/asm/cpuidle.h
create mode 100644 arch/riscv/include/asm/suspend.h
create mode 100644 arch/riscv/kernel/suspend.c
create mode 100644 arch/riscv/kernel/suspend_entry.S
create mode 100644 drivers/cpuidle/Kconfig.riscv
create mode 100644 drivers/cpuidle/cpuidle-riscv-sbi.c
create mode 100644 drivers/cpuidle/dt_idle_genpd.c
create mode 100644 drivers/cpuidle/dt_idle_genpd.h

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2.25.1