xref: /openbmc/u-boot/include/timer.h (revision d330e04d9d427a26381b59f40875af17f4c288a2)
1  /*
2   * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
3   *
4   * SPDX-License-Identifier:	GPL-2.0+
5   */
6  
7  #ifndef _TIMER_H_
8  #define _TIMER_H_
9  
10  /*
11   * dm_timer_init - initialize a timer for time keeping. On success
12   * initializes gd->timer so that lib/timer can use it for future
13   * referrence.
14   *
15   * @return - 0 on success or error number
16   */
17  int dm_timer_init(void);
18  
19  /*
20   * timer_conv_64 - convert 32-bit counter value to 64-bit
21   *
22   * @count: 32-bit counter value
23   * @return: 64-bit counter value
24   */
25  u64 timer_conv_64(u32 count);
26  
27  /*
28   * Get the current timer count
29   *
30   * @dev: The timer device
31   * @count: pointer that returns the current timer count
32   * @return: 0 if OK, -ve on error
33   */
34  int timer_get_count(struct udevice *dev, u64 *count);
35  
36  /*
37   * Get the timer input clock frequency
38   *
39   * @dev: The timer device
40   * @return: the timer input clock frequency
41   */
42  unsigned long timer_get_rate(struct udevice *dev);
43  
44  /*
45   * struct timer_ops - Driver model timer operations
46   *
47   * The uclass interface is implemented by all timer devices which use
48   * driver model.
49   */
50  struct timer_ops {
51  	/*
52  	 * Get the current timer count
53  	 *
54  	 * @dev: The timer device
55  	 * @count: pointer that returns the current 64-bit timer count
56  	 * @return: 0 if OK, -ve on error
57  	 */
58  	int (*get_count)(struct udevice *dev, u64 *count);
59  };
60  
61  /*
62   * struct timer_dev_priv - information about a device used by the uclass
63   *
64   * @clock_rate: the timer input clock frequency
65   */
66  struct timer_dev_priv {
67  	unsigned long clock_rate;
68  };
69  
70  /**
71   * timer_early_get_count() - Implement timer_get_count() before driver model
72   *
73   * If CONFIG_TIMER_EARLY is enabled, this function wil be called to return
74   * the current timer value before the proper driver model timer is ready.
75   * It should be implemented by one of the timer values. This is mostly useful
76   * for tracing.
77   */
78  u64 timer_early_get_count(void);
79  
80  /**
81   * timer_early_get_rate() - Get the timer rate before driver model
82   *
83   * If CONFIG_TIMER_EARLY is enabled, this function wil be called to return
84   * the current timer rate in Hz before the proper driver model timer is ready.
85   * It should be implemented by one of the timer values. This is mostly useful
86   * for tracing. This corresponds to the clock_rate value in struct
87   * timer_dev_priv.
88   */
89  unsigned long timer_early_get_rate(void);
90  
91  #endif	/* _TIMER_H_ */
92