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/* Copyright 2019 The ChromiumOS Authors
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef __CROS_EC_FPC_TIMEBASE_H
#define __CROS_EC_FPC_TIMEBASE_H
/**
* @file fpc_timebase.h
* @brief Timebase based on a system tick.
*
* Supplies tick counter and wait operation(s).
*/
#include <stdint.h>
#include "common.h"
/**
* @brief Reads the system tick counter.
*
* @details To handle tick counter wrap around when checking for timeout, make
* sure to do the calculation in the following manner:
* "if ((current_tick - old_tick) > timeout) {"
* Example: current time (uint32_t) = 10 ticks
* old time (uint32_t) = 30 ticks before overflow of uint32_t
* current_time - old_time = 10 - (2**32 - 30) -> wraps around to 40
*
* @return Tick count since fpc_timebase_init() call. [ms]
*/
uint32_t __unused fpc_timebase_get_tick(void);
/**
* @brief Busy wait.
*
* @param[in] ms Time to wait [ms].
* 0 => return immediately
* 1 => wait at least 1ms etc.
*/
void __unused fpc_timebase_busy_wait(uint32_t ms);
/**
* @brief Initializes timebase. Starts system tick counter.
*/
void __unused fpc_timebase_init(void);
#endif /* __CROS_EC_FPC_TIMEBASE_H */
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