include/hw/ptimer.h

17  * using ptimer_run(), the value will count downwards at the frequency
21  * and keep counting down, or to stop (as a one-shot timer).
23  * A transaction-based API is used for modifying ptimer state: all calls
29  * list of state-modifying functions and detailed semantics of the callback.)
31  * Forgetting to set the period/frequency (or setting it to zero) is a
49  *  - Starting to run with a period = 0 emits error message and stops the
52  *  - Setting period to 0 of the running timer emits error message and
55  *  - Starting to run with counter = 0 or setting it to "0" while timer
59  *  - Counter value of the running timer is one less than the actual value.
61  *  - Changing period/frequency of the running timer loses time elapsed
72  * re-trigger every period.  */
79 /* Starting to run with/setting counter to "0" won't re-load counter
101  * ptimer_init - Allocate and return a new ptimer
109  * transaction-based API for modifying ptimer state: all calls
111  *  - ptimer_set_period()
112  *  - ptimer_set_freq()
113  *  - ptimer_set_limit()
114  *  - ptimer_set_count()
115  *  - ptimer_run()
116  *  - ptimer_stop()
133  * ptimer_free - Free a ptimer
141  * ptimer_transaction_begin() - Start a ptimer modification transaction
147  * It is an error to call this function for a BH-based ptimer;
153  * ptimer_transaction_commit() - Commit a ptimer modification transaction
163  * ptimer_set_period - Set counter increment interval in nanoseconds
168  * particular frequency rather than a period then ptimer_set_freq()
177  * ptimer_set_period_from_clock - Set counter increment from a Clock
179  * @clk: pointer to Clock object to take period from
180  * @divisor: value to scale the clock frequency down by
182  * If the ptimer is being driven from a Clock, this is the preferred
185  * representation of the Clock period was converted to either a period
186  * in ns or a frequency in Hz.
188  * If the ptimer should run at the same frequency as the clock,
190  * frequency, pass 2, and so on.
195 void ptimer_set_period_from_clock(ptimer_state *s, const Clock *clock,
199  * ptimer_set_freq - Set counter frequency in Hz
201  * @freq: counter frequency in Hz
205  * as setting the frequency then this function is more appropriate,
215  * ptimer_get_limit - Get the configured limit of the ptimer
219  * of the down-counter; that is, the value which it will be
230  * ptimer_set_limit - Set the limit of the ptimer
235  * Set the limit value of the down-counter. The @reload flag can
245  * ptimer_get_count - Get the current value of the ptimer
248  * Return the current value of the down-counter. This will
255  * ptimer_set_count - Set the current value of the ptimer
259  * Set the value of the down-counter. If the counter is currently
269  * ptimer_run - Start a ptimer counting
271  * @oneshot: non-zero if this timer should only count down once
277  * start counting down again. If @oneshot is non-zero, then the counter
286  * ptimer_stop - Stop a ptimer counting