zephyr/subsys/pm/policy/policy_state_lock.c

87 lines
2.4 KiB
C

/*
* Copyright (c) 2018 Intel Corporation.
* Copyright (c) 2022 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/pm/policy.h>
#include <zephyr/pm/state.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/sys/atomic.h>
#include <zephyr/toolchain.h>
#if DT_HAS_COMPAT_STATUS_OKAY(zephyr_power_state)
#define DT_SUB_LOCK_INIT(node_id) \
{ .state = PM_STATE_DT_INIT(node_id), \
.substate_id = DT_PROP_OR(node_id, substate_id, 0), \
.lock = ATOMIC_INIT(0), \
},
/**
* State and substate lock structure.
*
* This struct is associating a reference counting to each <state,substate>
* couple to be used with the pm_policy_substate_lock_* functions.
*
* Operations on this array are in the order of O(n) with the number of power
* states and this is mostly due to the random nature of the substate value
* (that can be anything from a small integer value to a bitmask). We can
* probably do better with an hashmap.
*/
static struct {
enum pm_state state;
uint8_t substate_id;
atomic_t lock;
} substate_lock_t[] = {
DT_FOREACH_STATUS_OKAY(zephyr_power_state, DT_SUB_LOCK_INIT)
};
#endif
void pm_policy_state_lock_get(enum pm_state state, uint8_t substate_id)
{
#if DT_HAS_COMPAT_STATUS_OKAY(zephyr_power_state)
for (size_t i = 0; i < ARRAY_SIZE(substate_lock_t); i++) {
if (substate_lock_t[i].state == state &&
(substate_lock_t[i].substate_id == substate_id ||
substate_id == PM_ALL_SUBSTATES)) {
atomic_inc(&substate_lock_t[i].lock);
}
}
#endif
}
void pm_policy_state_lock_put(enum pm_state state, uint8_t substate_id)
{
#if DT_HAS_COMPAT_STATUS_OKAY(zephyr_power_state)
for (size_t i = 0; i < ARRAY_SIZE(substate_lock_t); i++) {
if (substate_lock_t[i].state == state &&
(substate_lock_t[i].substate_id == substate_id ||
substate_id == PM_ALL_SUBSTATES)) {
atomic_t cnt = atomic_dec(&substate_lock_t[i].lock);
ARG_UNUSED(cnt);
__ASSERT(cnt >= 1, "Unbalanced state lock get/put");
}
}
#endif
}
bool pm_policy_state_lock_is_active(enum pm_state state, uint8_t substate_id)
{
#if DT_HAS_COMPAT_STATUS_OKAY(zephyr_power_state)
for (size_t i = 0; i < ARRAY_SIZE(substate_lock_t); i++) {
if (substate_lock_t[i].state == state &&
(substate_lock_t[i].substate_id == substate_id ||
substate_id == PM_ALL_SUBSTATES)) {
return (atomic_get(&substate_lock_t[i].lock) != 0);
}
}
#endif
return false;
}