| Message ID | 20210209132040.5091-3-peter.maydell@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | New APIs for the Clock framework | expand |
On Tue, Feb 9, 2021 at 5:21 AM Peter Maydell <peter.maydell@linaro.org> wrote: > Add a new callback event type ClockPreUpdate, which is called on > period changes before the period is updated. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > Reviewed-by: Hao Wu <wuhaotsh@google.com> > --- > docs/devel/clocks.rst | 9 ++++++++- > include/hw/clock.h | 1 + > hw/core/clock.c | 3 +++ > 3 files changed, 12 insertions(+), 1 deletion(-) > > diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst > index cd344e3fe5d..f0391e76b4f 100644 > --- a/docs/devel/clocks.rst > +++ b/docs/devel/clocks.rst > @@ -181,7 +181,14 @@ events. > > The events currently supported are: > > - * ``ClockUpdate`` : called after the input clock's period has changed > + * ``ClockPreUpdate`` : called when the input clock's period is about to > + update. This is useful if the device needs to do some action for > + which it needs to know the old value of the clock period. During > + this callback, Clock API functions like ``clock_get()`` or > + ``clock_ticks_to_ns()`` will use the old period. > + * ``ClockUpdate`` : called after the input clock's period has changed. > + During this callback, Clock API functions like ``clock_ticks_to_ns()`` > + will use the new period. > > Note that a clock only has one callback: it is not possible to register > different functions for different events. You must register a single > diff --git a/include/hw/clock.h b/include/hw/clock.h > index 5c73b4e7ae9..d7a6673c29e 100644 > --- a/include/hw/clock.h > +++ b/include/hw/clock.h > @@ -30,6 +30,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(Clock, CLOCK) > */ > typedef enum ClockEvent { > ClockUpdate = 1, /* Clock period has just updated */ > + ClockPreUpdate = 2, /* Clock period is about to update */ > } ClockEvent; > > typedef void ClockCallback(void *opaque, ClockEvent event); > diff --git a/hw/core/clock.c b/hw/core/clock.c > index 71dc1f4de65..2c86091d8a3 100644 > --- a/hw/core/clock.c > +++ b/hw/core/clock.c > @@ -80,6 +80,9 @@ static void clock_propagate_period(Clock *clk, bool > call_callbacks) > > QLIST_FOREACH(child, &clk->children, sibling) { > if (child->period != clk->period) { > + if (call_callbacks) { > + clock_call_callback(child, ClockPreUpdate); > + } > child->period = clk->period; > trace_clock_update(CLOCK_PATH(child), CLOCK_PATH(clk), > CLOCK_PERIOD_TO_HZ(clk->period), > -- > 2.20.1 > > >
On 2/9/21 2:20 PM, Peter Maydell wrote: > Add a new callback event type ClockPreUpdate, which is called on > period changes before the period is updated. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > docs/devel/clocks.rst | 9 ++++++++- > include/hw/clock.h | 1 + > hw/core/clock.c | 3 +++ > 3 files changed, 12 insertions(+), 1 deletion(-) Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
On 13:20 Tue 09 Feb , Peter Maydell wrote: > Add a new callback event type ClockPreUpdate, which is called on > period changes before the period is updated. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Luc Michel <luc@lmichel.fr> > --- > docs/devel/clocks.rst | 9 ++++++++- > include/hw/clock.h | 1 + > hw/core/clock.c | 3 +++ > 3 files changed, 12 insertions(+), 1 deletion(-) > > diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst > index cd344e3fe5d..f0391e76b4f 100644 > --- a/docs/devel/clocks.rst > +++ b/docs/devel/clocks.rst > @@ -181,7 +181,14 @@ events. > > The events currently supported are: > > - * ``ClockUpdate`` : called after the input clock's period has changed > + * ``ClockPreUpdate`` : called when the input clock's period is about to > + update. This is useful if the device needs to do some action for > + which it needs to know the old value of the clock period. During > + this callback, Clock API functions like ``clock_get()`` or > + ``clock_ticks_to_ns()`` will use the old period. > + * ``ClockUpdate`` : called after the input clock's period has changed. > + During this callback, Clock API functions like ``clock_ticks_to_ns()`` > + will use the new period. > > Note that a clock only has one callback: it is not possible to register > different functions for different events. You must register a single > diff --git a/include/hw/clock.h b/include/hw/clock.h > index 5c73b4e7ae9..d7a6673c29e 100644 > --- a/include/hw/clock.h > +++ b/include/hw/clock.h > @@ -30,6 +30,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(Clock, CLOCK) > */ > typedef enum ClockEvent { > ClockUpdate = 1, /* Clock period has just updated */ > + ClockPreUpdate = 2, /* Clock period is about to update */ > } ClockEvent; > > typedef void ClockCallback(void *opaque, ClockEvent event); > diff --git a/hw/core/clock.c b/hw/core/clock.c > index 71dc1f4de65..2c86091d8a3 100644 > --- a/hw/core/clock.c > +++ b/hw/core/clock.c > @@ -80,6 +80,9 @@ static void clock_propagate_period(Clock *clk, bool call_callbacks) > > QLIST_FOREACH(child, &clk->children, sibling) { > if (child->period != clk->period) { > + if (call_callbacks) { > + clock_call_callback(child, ClockPreUpdate); > + } > child->period = clk->period; > trace_clock_update(CLOCK_PATH(child), CLOCK_PATH(clk), > CLOCK_PERIOD_TO_HZ(clk->period), > -- > 2.20.1 > --
diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst index cd344e3fe5d..f0391e76b4f 100644 --- a/docs/devel/clocks.rst +++ b/docs/devel/clocks.rst @@ -181,7 +181,14 @@ events. The events currently supported are: - * ``ClockUpdate`` : called after the input clock's period has changed + * ``ClockPreUpdate`` : called when the input clock's period is about to + update. This is useful if the device needs to do some action for + which it needs to know the old value of the clock period. During + this callback, Clock API functions like ``clock_get()`` or + ``clock_ticks_to_ns()`` will use the old period. + * ``ClockUpdate`` : called after the input clock's period has changed. + During this callback, Clock API functions like ``clock_ticks_to_ns()`` + will use the new period. Note that a clock only has one callback: it is not possible to register different functions for different events. You must register a single diff --git a/include/hw/clock.h b/include/hw/clock.h index 5c73b4e7ae9..d7a6673c29e 100644 --- a/include/hw/clock.h +++ b/include/hw/clock.h @@ -30,6 +30,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(Clock, CLOCK) */ typedef enum ClockEvent { ClockUpdate = 1, /* Clock period has just updated */ + ClockPreUpdate = 2, /* Clock period is about to update */ } ClockEvent; typedef void ClockCallback(void *opaque, ClockEvent event); diff --git a/hw/core/clock.c b/hw/core/clock.c index 71dc1f4de65..2c86091d8a3 100644 --- a/hw/core/clock.c +++ b/hw/core/clock.c @@ -80,6 +80,9 @@ static void clock_propagate_period(Clock *clk, bool call_callbacks) QLIST_FOREACH(child, &clk->children, sibling) { if (child->period != clk->period) { + if (call_callbacks) { + clock_call_callback(child, ClockPreUpdate); + } child->period = clk->period; trace_clock_update(CLOCK_PATH(child), CLOCK_PATH(clk), CLOCK_PERIOD_TO_HZ(clk->period),
Add a new callback event type ClockPreUpdate, which is called on period changes before the period is updated. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- docs/devel/clocks.rst | 9 ++++++++- include/hw/clock.h | 1 + hw/core/clock.c | 3 +++ 3 files changed, 12 insertions(+), 1 deletion(-)