qemu-e2k/hw/core/clock.c
Philippe Mathieu-Daudé 15aa2876d9 hw/clock: Let clock_set() return boolean value
Let clock_set() return a boolean value whether the clock
has been updated or not.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200806123858.30058-3-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-08-28 10:02:44 +01:00

136 lines
3.0 KiB
C

/*
* Hardware Clocks
*
* Copyright GreenSocs 2016-2020
*
* Authors:
* Frederic Konrad
* Damien Hedde
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "hw/clock.h"
#include "trace.h"
#define CLOCK_PATH(_clk) (_clk->canonical_path)
void clock_setup_canonical_path(Clock *clk)
{
g_free(clk->canonical_path);
clk->canonical_path = object_get_canonical_path(OBJECT(clk));
}
void clock_set_callback(Clock *clk, ClockCallback *cb, void *opaque)
{
clk->callback = cb;
clk->callback_opaque = opaque;
}
void clock_clear_callback(Clock *clk)
{
clock_set_callback(clk, NULL, NULL);
}
bool clock_set(Clock *clk, uint64_t period)
{
if (clk->period == period) {
return false;
}
trace_clock_set(CLOCK_PATH(clk), CLOCK_PERIOD_TO_NS(clk->period),
CLOCK_PERIOD_TO_NS(period));
clk->period = period;
return true;
}
static void clock_propagate_period(Clock *clk, bool call_callbacks)
{
Clock *child;
QLIST_FOREACH(child, &clk->children, sibling) {
if (child->period != clk->period) {
child->period = clk->period;
trace_clock_update(CLOCK_PATH(child), CLOCK_PATH(clk),
CLOCK_PERIOD_TO_NS(clk->period),
call_callbacks);
if (call_callbacks && child->callback) {
child->callback(child->callback_opaque);
}
clock_propagate_period(child, call_callbacks);
}
}
}
void clock_propagate(Clock *clk)
{
assert(clk->source == NULL);
trace_clock_propagate(CLOCK_PATH(clk));
clock_propagate_period(clk, true);
}
void clock_set_source(Clock *clk, Clock *src)
{
/* changing clock source is not supported */
assert(!clk->source);
trace_clock_set_source(CLOCK_PATH(clk), CLOCK_PATH(src));
clk->period = src->period;
QLIST_INSERT_HEAD(&src->children, clk, sibling);
clk->source = src;
clock_propagate_period(clk, false);
}
static void clock_disconnect(Clock *clk)
{
if (clk->source == NULL) {
return;
}
trace_clock_disconnect(CLOCK_PATH(clk));
clk->source = NULL;
QLIST_REMOVE(clk, sibling);
}
static void clock_initfn(Object *obj)
{
Clock *clk = CLOCK(obj);
QLIST_INIT(&clk->children);
}
static void clock_finalizefn(Object *obj)
{
Clock *clk = CLOCK(obj);
Clock *child, *next;
/* clear our list of children */
QLIST_FOREACH_SAFE(child, &clk->children, sibling, next) {
clock_disconnect(child);
}
/* remove us from source's children list */
clock_disconnect(clk);
g_free(clk->canonical_path);
}
static const TypeInfo clock_info = {
.name = TYPE_CLOCK,
.parent = TYPE_OBJECT,
.instance_size = sizeof(Clock),
.instance_init = clock_initfn,
.instance_finalize = clock_finalizefn,
};
static void clock_register_types(void)
{
type_register_static(&clock_info);
}
type_init(clock_register_types)