// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2015 ARM Limited
*/
#define pr_fmt(fmt) "psci: " fmt
#include <linux/acpi.h>
#include <linux/arm-smccc.h>
#include <linux/cpuidle.h>
#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/printk.h>
#include <linux/psci.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/suspend.h>
#include <uapi/linux/psci.h>
#include <asm/cpuidle.h>
#include <asm/cputype.h>
#include <asm/hypervisor.h>
#include <asm/system_misc.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
/*
* While a 64-bit OS can make calls with SMC32 calling conventions, for some
* calls it is necessary to use SMC64 to pass or return 64-bit values.
* For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
* (native-width) function ID.
*/
#ifdef CONFIG_64BIT
#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN64_##name
#else
#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN_##name
#endif
/*
* The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
* calls to its resident CPU, so we must avoid issuing those. We never migrate
* a Trusted OS even if it claims to be capable of migration -- doing so will
* require cooperation with a Trusted OS driver.
*/
static int resident_cpu = -1;
struct psci_operations psci_ops;
static enum arm_smccc_conduit psci_conduit = SMCCC_CONDUIT_NONE;
bool psci_tos_resident_on(int cpu)
{
return cpu == resident_cpu;
}
typedef unsigned long (psci_fn)(unsigned long, unsigned long,
unsigned long, unsigned long);
static psci_fn *invoke_psci_fn;
static struct psci_0_1_function_ids psci_0_1_function_ids;
struct psci_0_1_function_ids get_psci_0_1_function_ids(void)
{
return psci_0_1_function_ids;
}
#define PSCI_0_2_POWER_STATE_MASK \
(PSCI_0_2_POWER_STATE_ID_MASK | \
PSCI_0_2_POWER_STATE_TYPE_MASK | \
PSCI_0_2_POWER_STATE_AFFL_MASK)
#define PSCI_1_0_EXT_POWER_STATE_MASK \
(PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
static u32 psci_cpu_suspend_feature;
static bool psci_system_reset2_supported;
static inline bool psci_has_ext_power_state(void)
{
return psci_cpu_suspend_feature &
PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
}
bool psci_has_osi_support(void)
{
return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;
}
static inline bool psci_power_state_loses_context(u32 state)
{
const u32 mask = psci_has_ext_power_state() ?
PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
PSCI_0_2_POWER_STATE_TYPE_MASK;
return state & mask;
}
bool psci_power_state_is_valid(u32 state)
{
const u32 valid_mask = psci_has_ext_power_state() ?
PSCI_1_0_EXT_POWER_STATE_MASK :
PSCI_0_2_POWER_STATE_MASK;
return !(state & ~valid_mask);
}
static __always_inline unsigned long
__invoke_psci_fn_hvc(unsigned long function_id,
unsigned long arg0, unsigned long arg1,
unsigned long arg2)
{
struct arm_smccc_res res;
arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
return res.a0;
}
static __always_inline unsigned long
__invoke_psci_fn_smc(unsigned long function_id,
unsigned long arg0, unsigned long arg1,
unsigned long arg2)
{
struct arm_smccc_res res;
arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
return res.a0;
}
static __always_inline 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:
case PSCI_RET_INVALID_ADDRESS:
return -EINVAL;
case PSCI_RET_DENIED:
return -EPERM;
}
return -EINVAL;
}
static u32 psci_0_1_get_version(void)
{
return PSCI_VERSION(0, 1);
}
static u32 psci_0_2_get_version(void)
{
return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
}
int psci_set_osi_mode(bool enable)
{
unsigned long suspend_mode;
int err;
suspend_mode = enable ? PSCI_1_0_SUSPEND_MODE_OSI :
PSCI_1_0_SUSPEND_MODE_PC;
err = invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE, suspend_mode, 0, 0);
if (err < 0)
pr_info(FW_BUG "failed to set %s mode: %d\n",
enable ? "OSI" : "PC", err);
return psci_to_linux_errno(err);
}
static __always_inline int
__psci_cpu_suspend(u32 fn, u32 state, unsigned long entry_point)
{
int err;
err = invoke_psci_fn(fn, state, entry_point, 0);
return psci_to_linux_errno(err);
}
static __always_inline int
psci_0_1_cpu_suspend(u32 state, unsigned long entry_point)
{
return __psci_cpu_suspend(psci_0_1_function_ids.cpu_suspend,
state, entry_point);
}
static __always_inline int
psci_0_2_cpu_suspend(u32 state, unsigned long entry_point)
{
return __psci_cpu_suspend(PSCI_FN_NATIVE(0_2, CPU_SUSPEND),
state, entry_point);
}
static int __psci_cpu_off(u32 fn, u32 state)
{
int err;
err = invoke_psci_fn(fn, state, 0, 0);
return psci_to_linux_errno(err);
}
static int psci_0_1_cpu_off(u32 state)
{
return __psci_cpu_off(psci_0_1_function_ids.cpu_off, state);
}
static int psci_0_2_cpu_off(u32 state)
{
return __psci_cpu_off(PSCI_0_2_FN_CPU_OFF, state);
}
static int __psci_cpu_on(u32 fn, unsigned long cpuid, unsigned long entry_point)
{
int err;
err = invoke_psci_fn(fn, cpuid, entry_point, 0);
return psci_to_linux_errno(err);
}
static int psci_0_1_cpu_on(unsigned long cpuid, unsigned long entry_point)
{
return __psci_cpu_on(psci_0_1_function_ids.cpu_on, cpuid, entry_point);
}
static int psci_0_2_cpu_on(unsigned long cpuid, unsigned long entry_point)
{
return __psci_cpu_on(PSCI_FN_NATIVE(0_2, CPU_ON), cpuid, entry_point);
}
static int __psci_migrate(u32 fn, unsigned long cpuid)
{
int err;
err = invoke_psci_fn(fn, cpuid, 0, 0);
return psci_to_linux_errno(err);
}
static int psci_0_1_migrate(unsigned long cpuid)
{
return __psci_migrate(psci_0_1_function_ids.migrate, cpuid);
}
static int psci_0_2_migrate(unsigned long cpuid)
{
return __psci_migrate(PSCI_FN_NATIVE(0_2, MIGRATE), cpuid);
}
static int psci_affinity_info(unsigned long target_affinity,
unsigned long lowest_affinity_level)
{
return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
target_affinity, lowest_affinity_level, 0);
}
static int psci_migrate_info_type(void)
{
return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
}
static unsigned long psci_migrate_info_up_cpu(void)
{
return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
0, 0, 0);
}
static void set_conduit(enum arm_smccc_conduit conduit)
{
switch (conduit) {
case SMCCC_CONDUIT_HVC:
invoke_psci_fn = __invoke_psci_fn_hvc;
break;
case SMCCC_CONDUIT_SMC:
invoke_psci_fn = __invoke_psci_fn_smc;
break;
default:
WARN(1, "Unexpected PSCI conduit %d\n", conduit);
}
psci_conduit = conduit;
}
static int get_set_conduit_method(const 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)) {
set_conduit(SMCCC_CONDUIT_HVC);
} else if (!strcmp("smc", method)) {
set_conduit(SMCCC_CONDUIT_SMC);
} else {
pr_warn("invalid \"method\" property: %s\n", method);
return -EINVAL;
}
return 0;
}
static int psci_sys_reset(struct notifier_block *nb, unsigned long action,
void *data)
{
if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
psci_system_reset2_supported) {
/*
* reset_type[31] = 0 (architectural)
* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
* cookie = 0 (ignored by the implementation)
*/
invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
} else {
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
}
return NOTIFY_DONE;
}
static struct notifier_block psci_sys_reset_nb = {
.notifier_call = psci_sys_reset,
.priority = 129,
};
static void psci_sys_poweroff(void)
{
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
}
static int psci_features(u32 psci_func_id)
{
return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
psci_func_id, 0, 0);
}
#ifdef CONFIG_DEBUG_FS
#define PSCI_ID(ver, _name) \
{ .fn = PSCI_##ver##_FN_##_name, .name = #_name, }
#define PSCI_ID_NATIVE(ver, _name) \
{ .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, }
/* A table of all optional functions */
static const struct {
u32 fn;
const char *name;
} psci_fn_ids[] = {
PSCI_ID_NATIVE(0_2, MIGRATE),
PSCI_ID(0_2, MIGRATE_INFO_TYPE),
PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
PSCI_ID(1_0, CPU_FREEZE),
PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND),
PSCI_ID_NATIVE(1_0, NODE_HW_STATE),
PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND),
PSCI_ID(1_0, SET_SUSPEND_MODE),
PSCI_ID_NATIVE(1_0, STAT_RESIDENCY),
PSCI_ID_NATIVE(1_0, STAT_COUNT),
PSCI_ID_NATIVE(1_1, SYSTEM_RESET2),
PSCI_ID(1_1, MEM_PROTECT),
PSCI_ID_NATIVE(1_1, MEM_PROTECT_CHECK_RANGE),
};
static int psci_debugfs_read(struct seq_file *s, void *data)
{
int feature, type, i;
u32 ver;
ver = psci_ops.get_version();
seq_printf(s, "PSCIv%d.%d\n",
PSCI_VERSION_MAJOR(ver),
PSCI_VERSION_MINOR(ver));
/* PSCI_FEATURES is available only starting from 1.0 */
if (PSCI_VERSION_MAJOR(ver) < 1)
return 0;
feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
if (feature != PSCI_RET_NOT_SUPPORTED) {
ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
seq_printf(s, "SMC Calling Convention v%d.%d\n",
PSCI_VERSION_MAJOR(ver),
PSCI_VERSION_MINOR(ver));
} else {
seq_puts(s, "SMC Calling Convention v1.0 is assumed\n");
}
feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
if (feature < 0) {
seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature);
} else {
seq_printf(s, "OSI is %ssupported\n",
(feature & BIT(0)) ? "" : "not ");
seq_printf(s, "%s StateID format is used\n",
(feature & BIT(1)) ? "Extended" : "Original");
}
type = psci_ops.migrate_info_type();
if (type == PSCI_0_2_TOS_UP_MIGRATE ||
type == PSCI_0_2_TOS_UP_NO_MIGRATE) {
unsigned long cpuid;
seq_printf(s, "Trusted OS %smigrate capable\n",
type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : "");
cpuid = psci_migrate_info_up_cpu();
seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n",
cpuid, resident_cpu);
} else if (type == PSCI_0_2_TOS_MP) {
seq_puts(s, "Trusted OS migration not required\n");
} else {
if (type != PSCI_RET_NOT_SUPPORTED)
seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
}
for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) {
feature = psci_features(psci_fn_ids[i].fn);
if (feature == PSCI_RET_NOT_SUPPORTED)
continue;
if (feature < 0)
seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n",
psci_fn_ids[i].name, feature);
else
seq_printf(s, "%s is supported\n", psci_fn_ids[i].name);
}
return 0;
}
static int psci_debugfs_open(struct inode *inode, struct file *f)
{
return single_open(f, psci_debugfs_read, NULL);
}
static const struct file_operations psci_debugfs_ops = {
.owner = THIS_MODULE,
.open = psci_debugfs_open,
.release = single_release,
.read = seq_read,
.llseek = seq_lseek
};
static int __init psci_debugfs_init(void)
{
if (!invoke_psci_fn || !psci_ops.get_version)
return 0;
return PTR_ERR_OR_ZERO(debugfs_create_file("psci", 0444, NULL, NULL,
&psci_debugfs_ops));
}
late_initcall(psci_debugfs_init)
#endif
#ifdef CONFIG_CPU_IDLE
static noinstr int psci_suspend_finisher(unsigned long state)
{
u32 power_state = state;
phys_addr_t pa_cpu_resume;
pa_cpu_resume = __pa_symbol_nodebug((unsigned long)cpu_resume);
return psci_ops.cpu_suspend(power_state, pa_cpu_resume);
}
int psci_cpu_suspend_enter(u32 state)
{
int ret;
if (!psci_power_state_loses_context(state)) {
struct arm_cpuidle_irq_context context;
ct_cpuidle_enter();
arm_cpuidle_save_irq_context(&context);
ret = psci_ops.cpu_suspend(state, 0);
arm_cpuidle_restore_irq_context(&context);
ct_cpuidle_exit();
} else {
/*
* ARM64 cpu_suspend() wants to do ct_cpuidle_*() itself.
*/
if (!IS_ENABLED(CONFIG_ARM64))
ct_cpuidle_enter();
ret = cpu_suspend(state, psci_suspend_finisher);
if (!IS_ENABLED(CONFIG_ARM64))
ct_cpuidle_exit();
}
return ret;
}
#endif
static int psci_system_suspend(unsigned long unused)
{
int err;
phys_addr_t pa_cpu_resume = __pa_symbol(cpu_resume);
err = invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
pa_cpu_resume, 0, 0);
return psci_to_linux_errno(err);
}
static int psci_system_suspend_enter(suspend_state_t state)
{
return cpu_suspend(0, psci_system_suspend);
}
static const struct platform_suspend_ops psci_suspend_ops = {
.valid = suspend_valid_only_mem,
.enter = psci_system_suspend_enter,
};
static void __init psci_init_system_reset2(void)
{
int ret;
ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
if (ret != PSCI_RET_NOT_SUPPORTED)
psci_system_reset2_supported = true;
}
static void __init psci_init_system_suspend(void)
{
int ret;
if (!IS_ENABLED(CONFIG_SUSPEND))
return;
ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
if (ret != PSCI_RET_NOT_SUPPORTED)
suspend_set_ops(&psci_suspend_ops);
}
static void __init psci_init_cpu_suspend(void)
{
int feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
if (feature != PSCI_RET_NOT_SUPPORTED)
psci_cpu_suspend_feature = feature;
}
/*
* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
* return DENIED (which would be fatal).
*/
static void __init psci_init_migrate(void)
{
unsigned long cpuid;
int type, cpu = -1;
type = psci_ops.migrate_info_type();
if (type == PSCI_0_2_TOS_MP) {
pr_info("Trusted OS migration not required\n");
return;
}
if (type == PSCI_RET_NOT_SUPPORTED) {
pr_info("MIGRATE_INFO_TYPE not supported.\n");
return;
}
if (type != PSCI_0_2_TOS_UP_MIGRATE &&
type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
return;
}
cpuid = psci_migrate_info_up_cpu();
if (cpuid & ~MPIDR_HWID_BITMASK) {
pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
cpuid);
return;
}
cpu = get_logical_index(cpuid);
resident_cpu = cpu >= 0 ? cpu : -1;
pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
}
static void __init psci_init_smccc(void)
{
u32 ver = ARM_SMCCC_VERSION_1_0;
int feature;
feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
if (feature != PSCI_RET_NOT_SUPPORTED) {
u32 ret;
ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
if (ret >= ARM_SMCCC_VERSION_1_1) {
arm_smccc_version_init(ret, psci_conduit);
ver = ret;
}
}
/*
* Conveniently, the SMCCC and PSCI versions are encoded the
* same way. No, this isn't accidental.
*/
pr_info("SMC Calling Convention v%d.%d\n",
PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
}
static void __init psci_0_2_set_functions(void)
{
pr_info("Using standard PSCI v0.2 function IDs\n");
psci_ops = (struct psci_operations){
.get_version = psci_0_2_get_version,
.cpu_suspend = psci_0_2_cpu_suspend,
.cpu_off = psci_0_2_cpu_off,
.cpu_on = psci_0_2_cpu_on,
.migrate = psci_0_2_migrate,
.affinity_info = psci_affinity_info,
.migrate_info_type = psci_migrate_info_type,
};
register_restart_handler(&psci_sys_reset_nb);
pm_power_off = psci_sys_poweroff;
}
/*
* Probe function for PSCI firmware versions >= 0.2
*/
static int __init psci_probe(void)
{
u32 ver = psci_0_2_get_version();
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) {
pr_err("Conflicting PSCI version detected.\n");
return -EINVAL;
}
psci_0_2_set_functions();
psci_init_migrate();
if (PSCI_VERSION_MAJOR(ver) >= 1) {
psci_init_smccc();
psci_init_cpu_suspend();
psci_init_system_suspend();
psci_init_system_reset2();
kvm_init_hyp_services();
}
return 0;
}
typedef int (*psci_initcall_t)(const struct device_node *);
/*
* PSCI init function for PSCI versions >=0.2
*
* Probe based on PSCI PSCI_VERSION function
*/
static int __init psci_0_2_init(const struct device_node *np)
{
int err;
err = get_set_conduit_method(np);
if (err)
return err;
/*
* Starting with v0.2, the PSCI specification introduced a call
* (PSCI_VERSION) that allows probing the firmware version, so
* that PSCI function IDs and version specific initialization
* can be carried out according to the specific version reported
* by firmware
*/
return psci_probe();
}
/*
* PSCI < v0.2 get PSCI Function IDs via DT.
*/
static int __init psci_0_1_init(const struct device_node *np)
{
u32 id;
int err;
err = get_set_conduit_method(np);
if (err)
return err;
pr_info("Using PSCI v0.1 Function IDs from DT\n");
psci_ops.get_version = psci_0_1_get_version;
if (!of_property_read_u32(np, "cpu_suspend", &id)) {
psci_0_1_function_ids.cpu_suspend = id;
psci_ops.cpu_suspend = psci_0_1_cpu_suspend;
}
if (!of_property_read_u32(np, "cpu_off", &id)) {
psci_0_1_function_ids.cpu_off = id;
psci_ops.cpu_off = psci_0_1_cpu_off;
}
if (!of_property_read_u32(np, "cpu_on", &id)) {
psci_0_1_function_ids.cpu_on = id;
psci_ops.cpu_on = psci_0_1_cpu_on;
}
if (!of_property_read_u32(np, "migrate", &id)) {
psci_0_1_function_ids.migrate = id;
psci_ops.migrate = psci_0_1_migrate;
}
return 0;
}
static int __init psci_1_0_init(const struct device_node *np)
{
int err;
err = psci_0_2_init(np);
if (err)
return err;
if (psci_has_osi_support()) {
pr_info("OSI mode supported.\n");
/* Default to PC mode. */
psci_set_osi_mode(false);
}
return 0;
}
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},
{ .compatible = "arm,psci-1.0", .data = psci_1_0_init},
{},
};
int __init psci_dt_init(void)
{
struct device_node *np;
const struct of_device_id *matched_np;
psci_initcall_t init_fn;
int ret;
np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
if (!np || !of_device_is_available(np))
return -ENODEV;
init_fn = (psci_initcall_t)matched_np->data;
ret = init_fn(np);
of_node_put(np);
return ret;
}
#ifdef CONFIG_ACPI
/*
* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
* explicitly clarified in SBBR
*/
int __init psci_acpi_init(void)
{
if (!acpi_psci_present()) {
pr_info("is not implemented in ACPI.\n");
return -EOPNOTSUPP;
}
pr_info("probing for conduit method from ACPI.\n");
if (acpi_psci_use_hvc())
set_conduit(SMCCC_CONDUIT_HVC);
else
set_conduit(SMCCC_CONDUIT_SMC);
return psci_probe();
}
#endif
Codebase Browser
linux