diff options
author | Palmer Dabbelt <palmer@rivosinc.com> | 2024-03-20 03:51:41 +0300 |
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committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-03-20 18:56:06 +0300 |
commit | 85ab6fdf3791c68aa7b8eb484f68855b8a6b9884 (patch) | |
tree | ca77d26acc1326d9b66b96ec821e8cf4b3ca1ee9 /drivers | |
parent | 728e7ea2b56d0eba5a3c952e6c613523160723c8 (diff) | |
parent | 359df7c5be4ba5c57f641010be7237ad9f09ea53 (diff) | |
download | linux-85ab6fdf3791c68aa7b8eb484f68855b8a6b9884.tar.xz |
Merge patch series "RISC-V: ACPI: Add LPI support"
Sunil V L <sunilvl@ventanamicro.com> says:
This series adds support for Low Power Idle (LPI) on ACPI based
platforms.
LPI is described in the ACPI spec [1]. RISC-V FFH spec required to
enable this is available at [2].
[1] - https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html#lpi-low-power-idle-states
[2] - https://github.com/riscv-non-isa/riscv-acpi-ffh/releases/download/v/riscv-ffh.pdf
* b4-shazam-merge:
ACPI: Enable ACPI_PROCESSOR for RISC-V
ACPI: RISC-V: Add LPI driver
cpuidle: RISC-V: Move few functions to arch/riscv
Link: https://lore.kernel.org/r/20240118062930.245937-1-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/Kconfig | 2 | ||||
-rw-r--r-- | drivers/acpi/riscv/Makefile | 3 | ||||
-rw-r--r-- | drivers/acpi/riscv/cpuidle.c | 81 | ||||
-rw-r--r-- | drivers/cpuidle/cpuidle-riscv-sbi.c | 49 |
4 files changed, 89 insertions, 46 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 3c3f8037ebed..1606eb622a9f 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -286,7 +286,7 @@ config ACPI_CPPC_LIB config ACPI_PROCESSOR tristate "Processor" - depends on X86 || ARM64 || LOONGARCH + depends on X86 || ARM64 || LOONGARCH || RISCV select ACPI_PROCESSOR_IDLE select ACPI_CPU_FREQ_PSS if X86 || LOONGARCH select THERMAL diff --git a/drivers/acpi/riscv/Makefile b/drivers/acpi/riscv/Makefile index 8b3b126e0b94..7309d92dd477 100644 --- a/drivers/acpi/riscv/Makefile +++ b/drivers/acpi/riscv/Makefile @@ -1,2 +1,3 @@ # SPDX-License-Identifier: GPL-2.0-only -obj-y += rhct.o +obj-y += rhct.o +obj-$(CONFIG_ACPI_PROCESSOR_IDLE) += cpuidle.o diff --git a/drivers/acpi/riscv/cpuidle.c b/drivers/acpi/riscv/cpuidle.c new file mode 100644 index 000000000000..624f9bbdb58c --- /dev/null +++ b/drivers/acpi/riscv/cpuidle.c @@ -0,0 +1,81 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024, Ventana Micro Systems Inc + * Author: Sunil V L <sunilvl@ventanamicro.com> + * + */ + +#include <linux/acpi.h> +#include <acpi/processor.h> +#include <linux/cpu_pm.h> +#include <linux/cpuidle.h> +#include <linux/suspend.h> +#include <asm/cpuidle.h> +#include <asm/sbi.h> +#include <asm/suspend.h> + +#define RISCV_FFH_LPI_TYPE_MASK GENMASK_ULL(63, 60) +#define RISCV_FFH_LPI_RSVD_MASK GENMASK_ULL(59, 32) + +#define RISCV_FFH_LPI_TYPE_SBI BIT_ULL(60) + +static int acpi_cpu_init_idle(unsigned int cpu) +{ + int i; + struct acpi_lpi_state *lpi; + struct acpi_processor *pr = per_cpu(processors, cpu); + + if (unlikely(!pr || !pr->flags.has_lpi)) + return -EINVAL; + + if (!riscv_sbi_hsm_is_supported()) + return -ENODEV; + + if (pr->power.count <= 1) + return -ENODEV; + + for (i = 1; i < pr->power.count; i++) { + u32 state; + + lpi = &pr->power.lpi_states[i]; + + /* + * Validate Entry Method as per FFH spec. + * bits[63:60] should be 0x1 + * bits[59:32] should be 0x0 + * bits[31:0] represent a SBI power_state + */ + if (((lpi->address & RISCV_FFH_LPI_TYPE_MASK) != RISCV_FFH_LPI_TYPE_SBI) || + (lpi->address & RISCV_FFH_LPI_RSVD_MASK)) { + pr_warn("Invalid LPI entry method %#llx\n", lpi->address); + return -EINVAL; + } + + state = lpi->address; + if (!riscv_sbi_suspend_state_is_valid(state)) { + pr_warn("Invalid SBI power state %#x\n", state); + return -EINVAL; + } + } + + return 0; +} + +int acpi_processor_ffh_lpi_probe(unsigned int cpu) +{ + return acpi_cpu_init_idle(cpu); +} + +int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) +{ + u32 state = lpi->address; + + if (state & SBI_HSM_SUSP_NON_RET_BIT) + return CPU_PM_CPU_IDLE_ENTER_PARAM(riscv_sbi_hart_suspend, + lpi->index, + state); + else + return CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(riscv_sbi_hart_suspend, + lpi->index, + state); +} diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.c b/drivers/cpuidle/cpuidle-riscv-sbi.c index e8094fc92491..a6e123dfe394 100644 --- a/drivers/cpuidle/cpuidle-riscv-sbi.c +++ b/drivers/cpuidle/cpuidle-riscv-sbi.c @@ -73,26 +73,6 @@ static inline bool sbi_is_domain_state_available(void) return data->available; } -static int sbi_suspend_finisher(unsigned long suspend_type, - unsigned long resume_addr, - unsigned long opaque) -{ - struct sbiret ret; - - ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_SUSPEND, - suspend_type, resume_addr, opaque, 0, 0, 0); - - return (ret.error) ? sbi_err_map_linux_errno(ret.error) : 0; -} - -static int sbi_suspend(u32 state) -{ - if (state & SBI_HSM_SUSP_NON_RET_BIT) - return cpu_suspend(state, sbi_suspend_finisher); - else - return sbi_suspend_finisher(state, 0, 0); -} - static __cpuidle int sbi_cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, int idx) { @@ -100,9 +80,9 @@ static __cpuidle int sbi_cpuidle_enter_state(struct cpuidle_device *dev, u32 state = states[idx]; if (state & SBI_HSM_SUSP_NON_RET_BIT) - return CPU_PM_CPU_IDLE_ENTER_PARAM(sbi_suspend, idx, state); + return CPU_PM_CPU_IDLE_ENTER_PARAM(riscv_sbi_hart_suspend, idx, state); else - return CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(sbi_suspend, + return CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(riscv_sbi_hart_suspend, idx, state); } @@ -133,7 +113,7 @@ static __cpuidle int __sbi_enter_domain_idle_state(struct cpuidle_device *dev, else state = states[idx]; - ret = sbi_suspend(state) ? -1 : idx; + ret = riscv_sbi_hart_suspend(state) ? -1 : idx; ct_cpuidle_exit(); @@ -206,17 +186,6 @@ static const struct of_device_id sbi_cpuidle_state_match[] = { { }, }; -static bool sbi_suspend_state_is_valid(u32 state) -{ - if (state > SBI_HSM_SUSPEND_RET_DEFAULT && - state < SBI_HSM_SUSPEND_RET_PLATFORM) - return false; - if (state > SBI_HSM_SUSPEND_NON_RET_DEFAULT && - state < SBI_HSM_SUSPEND_NON_RET_PLATFORM) - return false; - return true; -} - static int sbi_dt_parse_state_node(struct device_node *np, u32 *state) { int err = of_property_read_u32(np, "riscv,sbi-suspend-param", state); @@ -226,7 +195,7 @@ static int sbi_dt_parse_state_node(struct device_node *np, u32 *state) return err; } - if (!sbi_suspend_state_is_valid(*state)) { + if (!riscv_sbi_suspend_state_is_valid(*state)) { pr_warn("Invalid SBI suspend state %#x\n", *state); return -EINVAL; } @@ -607,16 +576,8 @@ static int __init sbi_cpuidle_init(void) int ret; struct platform_device *pdev; - /* - * The SBI HSM suspend function is only available when: - * 1) SBI version is 0.3 or higher - * 2) SBI HSM extension is available - */ - if ((sbi_spec_version < sbi_mk_version(0, 3)) || - !sbi_probe_extension(SBI_EXT_HSM)) { - pr_info("HSM suspend not available\n"); + if (!riscv_sbi_hsm_is_supported()) return 0; - } ret = platform_driver_register(&sbi_cpuidle_driver); if (ret) |