From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/arm/kernel/psci.c | 299 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 arch/arm/kernel/psci.c (limited to 'arch/arm/kernel/psci.c') diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c new file mode 100644 index 000000000..f90fdf4ce --- /dev/null +++ b/arch/arm/kernel/psci.c @@ -0,0 +1,299 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2012 ARM Limited + * + * Author: Will Deacon + */ + +#define pr_fmt(fmt) "psci: " fmt + +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +struct psci_operations psci_ops; + +static int (*invoke_psci_fn)(u32, u32, u32, u32); +typedef int (*psci_initcall_t)(const struct device_node *); + +asmlinkage int __invoke_psci_fn_hvc(u32, u32, u32, u32); +asmlinkage int __invoke_psci_fn_smc(u32, u32, u32, u32); + +enum psci_function { + PSCI_FN_CPU_SUSPEND, + PSCI_FN_CPU_ON, + PSCI_FN_CPU_OFF, + PSCI_FN_MIGRATE, + PSCI_FN_AFFINITY_INFO, + PSCI_FN_MIGRATE_INFO_TYPE, + PSCI_FN_MAX, +}; + +static u32 psci_function_id[PSCI_FN_MAX]; + +static int psci_to_linux_errno(int errno) +{ + switch (errno) { + case PSCI_RET_SUCCESS: + return 0; + case PSCI_RET_NOT_SUPPORTED: + return -EOPNOTSUPP; + case PSCI_RET_INVALID_PARAMS: + return -EINVAL; + case PSCI_RET_DENIED: + return -EPERM; + }; + + return -EINVAL; +} + +static u32 psci_power_state_pack(struct psci_power_state state) +{ + return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT) + & PSCI_0_2_POWER_STATE_ID_MASK) | + ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT) + & PSCI_0_2_POWER_STATE_TYPE_MASK) | + ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT) + & PSCI_0_2_POWER_STATE_AFFL_MASK); +} + +static int psci_get_version(void) +{ + int err; + + err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0); + return err; +} + +static int psci_cpu_suspend(struct psci_power_state state, + unsigned long entry_point) +{ + int err; + u32 fn, power_state; + + fn = psci_function_id[PSCI_FN_CPU_SUSPEND]; + power_state = psci_power_state_pack(state); + err = invoke_psci_fn(fn, power_state, entry_point, 0); + return psci_to_linux_errno(err); +} + +static int psci_cpu_off(struct psci_power_state state) +{ + int err; + u32 fn, power_state; + + fn = psci_function_id[PSCI_FN_CPU_OFF]; + power_state = psci_power_state_pack(state); + err = invoke_psci_fn(fn, power_state, 0, 0); + return psci_to_linux_errno(err); +} + +static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point) +{ + int err; + u32 fn; + + fn = psci_function_id[PSCI_FN_CPU_ON]; + err = invoke_psci_fn(fn, cpuid, entry_point, 0); + return psci_to_linux_errno(err); +} + +static int psci_migrate(unsigned long cpuid) +{ + int err; + u32 fn; + + fn = psci_function_id[PSCI_FN_MIGRATE]; + err = invoke_psci_fn(fn, cpuid, 0, 0); + return psci_to_linux_errno(err); +} + +static int psci_affinity_info(unsigned long target_affinity, + unsigned long lowest_affinity_level) +{ + int err; + u32 fn; + + fn = psci_function_id[PSCI_FN_AFFINITY_INFO]; + err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0); + return err; +} + +static int psci_migrate_info_type(void) +{ + int err; + u32 fn; + + fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE]; + err = invoke_psci_fn(fn, 0, 0, 0); + return err; +} + +static int get_set_conduit_method(struct device_node *np) +{ + const char *method; + + pr_info("probing for conduit method from DT.\n"); + + if (of_property_read_string(np, "method", &method)) { + pr_warn("missing \"method\" property\n"); + return -ENXIO; + } + + if (!strcmp("hvc", method)) { + invoke_psci_fn = __invoke_psci_fn_hvc; + } else if (!strcmp("smc", method)) { + invoke_psci_fn = __invoke_psci_fn_smc; + } else { + pr_warn("invalid \"method\" property: %s\n", method); + return -EINVAL; + } + return 0; +} + +static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd) +{ + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); +} + +static void psci_sys_poweroff(void) +{ + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); +} + +/* + * PSCI Function IDs for v0.2+ are well defined so use + * standard values. + */ +static int psci_0_2_init(struct device_node *np) +{ + int err, ver; + + err = get_set_conduit_method(np); + + if (err) + goto out_put_node; + + ver = psci_get_version(); + + if (ver == PSCI_RET_NOT_SUPPORTED) { + /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */ + pr_err("PSCI firmware does not comply with the v0.2 spec.\n"); + err = -EOPNOTSUPP; + goto out_put_node; + } else { + pr_info("PSCIv%d.%d detected in firmware.\n", + PSCI_VERSION_MAJOR(ver), + PSCI_VERSION_MINOR(ver)); + + if (PSCI_VERSION_MAJOR(ver) == 0 && + PSCI_VERSION_MINOR(ver) < 2) { + err = -EINVAL; + pr_err("Conflicting PSCI version detected.\n"); + goto out_put_node; + } + } + + pr_info("Using standard PSCI v0.2 function IDs\n"); + psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_CPU_SUSPEND; + psci_ops.cpu_suspend = psci_cpu_suspend; + + psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF; + psci_ops.cpu_off = psci_cpu_off; + + psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_CPU_ON; + psci_ops.cpu_on = psci_cpu_on; + + psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_MIGRATE; + psci_ops.migrate = psci_migrate; + + psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN_AFFINITY_INFO; + psci_ops.affinity_info = psci_affinity_info; + + psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] = + PSCI_0_2_FN_MIGRATE_INFO_TYPE; + psci_ops.migrate_info_type = psci_migrate_info_type; + + arm_pm_restart = psci_sys_reset; + + pm_power_off = psci_sys_poweroff; + +out_put_node: + of_node_put(np); + return err; +} + +/* + * PSCI < v0.2 get PSCI Function IDs via DT. + */ +static int psci_0_1_init(struct device_node *np) +{ + u32 id; + int err; + + err = get_set_conduit_method(np); + + if (err) + goto out_put_node; + + pr_info("Using PSCI v0.1 Function IDs from DT\n"); + + if (!of_property_read_u32(np, "cpu_suspend", &id)) { + psci_function_id[PSCI_FN_CPU_SUSPEND] = id; + psci_ops.cpu_suspend = psci_cpu_suspend; + } + + if (!of_property_read_u32(np, "cpu_off", &id)) { + psci_function_id[PSCI_FN_CPU_OFF] = id; + psci_ops.cpu_off = psci_cpu_off; + } + + if (!of_property_read_u32(np, "cpu_on", &id)) { + psci_function_id[PSCI_FN_CPU_ON] = id; + psci_ops.cpu_on = psci_cpu_on; + } + + if (!of_property_read_u32(np, "migrate", &id)) { + psci_function_id[PSCI_FN_MIGRATE] = id; + psci_ops.migrate = psci_migrate; + } + +out_put_node: + of_node_put(np); + return err; +} + +static const struct of_device_id psci_of_match[] __initconst = { + { .compatible = "arm,psci", .data = psci_0_1_init}, + { .compatible = "arm,psci-0.2", .data = psci_0_2_init}, + {}, +}; + +int __init psci_init(void) +{ + struct device_node *np; + const struct of_device_id *matched_np; + psci_initcall_t init_fn; + + np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np); + if (!np) + return -ENODEV; + + init_fn = (psci_initcall_t)matched_np->data; + return init_fn(np); +} -- cgit v1.2.3-54-g00ecf