include/hw/clock.h

4  * Copyright GreenSocs 2016-2020
11  * See the COPYING file in the top-level directory.
19 #include "qemu/host-utils.h"
39  * clock store a value representing the clock's period in 2^-32ns unit.
41  *  + periods from 2^-32ns up to 4seconds
65  * @source: source (or parent in clock tree) of the clock
66  * @children: list of clocks connected to this one (it is their source)
89     Clock *source;  member
110  * @clk: clock
114 void clock_setup_canonical_path(Clock *clk);
131  * @clk: the clock to register the callback into
141 void clock_set_callback(Clock *clk, ClockCallback *cb,
146  * @clk: the clock.
147  * @src: the source clock
149  * Setup @src as the clock source of @clk. The current @src period
150  * value is also copied to @clk and its subtree but no callback is
152  * Further @src update will be propagated to @clk and its subtree.
154 void clock_set_source(Clock *clk, Clock *src);
158  * @clk: the clock
160  * Returns true if the clock has a source clock connected to it.
166 static inline bool clock_has_source(const Clock *clk)  in clock_has_source()  argument
168     return clk->source != NULL;  in clock_has_source()
173  * @clk: the clock to initialize.
176  * Set the local cached period value of @clk to @value.
180 bool clock_set(Clock *clk, uint64_t value);
182 static inline bool clock_set_hz(Clock *clk, unsigned hz)  in clock_set_hz()  argument
184     return clock_set(clk, CLOCK_PERIOD_FROM_HZ(hz));  in clock_set_hz()
187 static inline bool clock_set_ns(Clock *clk, unsigned ns)  in clock_set_ns()  argument
189     return clock_set(clk, CLOCK_PERIOD_FROM_NS(ns));  in clock_set_ns()
194  * @clk: the clock
198  * It is an error to call this function on a clock which has a source.
202 void clock_propagate(Clock *clk);
206  * @clk: the clock to update.
209  * Update the @clk to the new @value. All connected clocks will be informed
213 static inline void clock_update(Clock *clk, uint64_t value)  in clock_update()  argument
215     if (clock_set(clk, value)) {  in clock_update()
216         clock_propagate(clk);  in clock_update()
220 static inline void clock_update_hz(Clock *clk, unsigned hz)  in clock_update_hz()  argument
222     clock_update(clk, CLOCK_PERIOD_FROM_HZ(hz));  in clock_update_hz()
225 static inline void clock_update_ns(Clock *clk, unsigned ns)  in clock_update_ns()  argument
227     clock_update(clk, CLOCK_PERIOD_FROM_NS(ns));  in clock_update_ns()
232  * @clk: the clk to fetch the clock
236 static inline uint64_t clock_get(const Clock *clk)  in clock_get()  argument
238     return clk->period;  in clock_get()
241 static inline unsigned clock_get_hz(Clock *clk)  in clock_get_hz()  argument
243     return CLOCK_PERIOD_TO_HZ(clock_get(clk));  in clock_get_hz()
248  * @clk: the clock to query
259  * The result could in theory be too large to fit in a 64-bit
265  * and callers can reasonably not special-case the saturated result.
267 static inline uint64_t clock_ticks_to_ns(const Clock *clk, uint64_t ticks)  in clock_ticks_to_ns()  argument
272      * clk->period is the period in units of 2^-32 ns, so  in clock_ticks_to_ns()
273      * (clk->period * ticks) is the required length of time in those  in clock_ticks_to_ns()
275      * 2^32, which is the same as shifting the 128-bit multiplication  in clock_ticks_to_ns()
278     mulu64(&ns_low, &ns_high, clk->period, ticks);  in clock_ticks_to_ns()
287  * @clk: the clock to query
298  * For some inputs the result could overflow a 64-bit value (because
300  * cases we truncate the result to a 64-bit value. This is on the
302  * a 32-bit or 64-bit guest register value, so wrapping either cannot
305 static inline uint64_t clock_ns_to_ticks(const Clock *clk, uint64_t ns)  in clock_ns_to_ticks()  argument
315     if (clk->period == 0) {  in clock_ns_to_ticks()
319     divu128(&lo, &hi, clk->period);  in clock_ns_to_ticks()
325  * @clk: a clock
329 static inline bool clock_is_enabled(const Clock *clk)  in clock_is_enabled()  argument
331     return clock_get(clk) != 0;  in clock_is_enabled()
335  * clock_display_freq: return human-readable representation of clock frequency
336  * @clk: clock
338  * Return a string which has a human-readable representation of the
344 char *clock_display_freq(Clock *clk);
348  * @clk: clock
371 bool clock_set_mul_div(Clock *clk, uint32_t multiplier, uint32_t divider);