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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
*/
#ifndef _TIMER_H_
#define _TIMER_H_
#define timer_get_ops(dev) ((struct timer_ops *)(dev)->driver->ops)
/**
* dm_timer_init() - set up a timer for time keeping
*
* Sets up gd->timer if the device is not already bound, making sure it is
* probed and ready for use
*
* On success, inits gd->timer so that lib/timer can use it for future reference
*
* Returns: 0 on success, -EAGAIN if driver model is not ready yet, -ENODEV if
* no timer could be found, other error if the timer could not be bound or
* probed
*/
int dm_timer_init(void);
/**
* timer_timebase_fallback() - Helper for timers using timebase fallback
* @dev: A timer partially-probed timer device
*
* This is a helper function designed for timers which need to fall back on the
* cpu's timebase. This function is designed to be called during the driver's
* probe(). If there is a clocks or clock-frequency property in the timer's
* binding, then it will be used. Otherwise, the timebase of the current cpu
* will be used. This is initialized by the cpu driver, and usually gotten from
* ``/cpus/timebase-frequency`` or ``/cpus/cpu@X/timebase-frequency``.
*
* Return: 0 if OK, or negative error code on failure
*/
int timer_timebase_fallback(struct udevice *dev);
/**
* timer_conv_64() - convert 32-bit counter value to 64-bit
* @count: 32-bit counter value
*
* Return: 64-bit counter value
*/
u64 timer_conv_64(u32 count);
/**
* timer_get_count() - Get the current timer count
* @dev: The timer device
* @count: pointer that returns the current timer count
*
* Return: 0 if OK, -ve on error
*/
int timer_get_count(struct udevice *dev, u64 *count);
/**
* timer_get_rate() - Get the timer input clock frequency
* @dev: The timer device
*
* Return: the timer input clock frequency
*/
unsigned long timer_get_rate(struct udevice *dev);
/**
* struct timer_ops - Driver model timer operations
*
* The uclass interface is implemented by all timer devices which use
* driver model.
*/
struct timer_ops {
/**
* @get_count: Get the current timer count
*
* @dev: The timer device
*
* This function may be called at any time after the driver is probed.
* All necessary initialization must be completed by the time probe()
* returns. The count returned by this functions should be monotonic.
* This function must succeed.
*
* Return: The current 64-bit timer count
*/
u64 (*get_count)(struct udevice *dev);
};
/**
* struct timer_dev_priv - information about a device used by the uclass
*
* @clock_rate: the timer input clock frequency
*/
struct timer_dev_priv {
unsigned long clock_rate;
};
/**
* timer_early_get_count() - Implement timer_get_count() before driver model
*
* If ``CONFIG_TIMER_EARLY`` is enabled, this function wil be called to return
* the current timer value before the proper driver model timer is ready.
* It should be implemented by one of the timer values. This is mostly useful
* for tracing.
*/
u64 timer_early_get_count(void);
/**
* timer_early_get_rate() - Get the timer rate before driver model
*
* If ``CONFIG_TIMER_EARLY`` is enabled, this function wil be called to return
* the current timer rate in Hz before the proper driver model timer is ready.
* It should be implemented by one of the timer values. This is mostly useful
* for tracing. This corresponds to the clock_rate value in struct
* timer_dev_priv.
*/
unsigned long timer_early_get_rate(void);
#endif /* _TIMER_H_ */
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