include/timer.h

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