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charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2607:f8b0:4864:20::a30; envelope-from=alistair23@gmail.com; helo=mail-vk1-xa30.google.com X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Mar 26, 2024 at 1:29=E2=80=AFAM Philippe Mathieu-Daud=C3=A9 wrote: > > Let clock_set_mul_div() return a boolean value whether the > clock has been updated or not, similarly to clock_set(). > > Return early when clock_set_mul_div() is called with > same mul/div values the clock has. > > Acked-by: Luc Michel > Signed-off-by: Philippe Mathieu-Daud=C3=A9 Reviewed-by: Alistair Francis Alistair > --- > docs/devel/clocks.rst | 4 ++++ > include/hw/clock.h | 4 +++- > hw/core/clock.c | 8 +++++++- > 3 files changed, 14 insertions(+), 2 deletions(-) > > diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst > index c4d14bde04..b2d1148cdb 100644 > --- a/docs/devel/clocks.rst > +++ b/docs/devel/clocks.rst > @@ -279,6 +279,10 @@ You can change the multiplier and divider of a clock= at runtime, > so you can use this to model clock controller devices which > have guest-programmable frequency multipliers or dividers. > > +Similary to ``clock_set()``, ``clock_set_mul_div()`` returns ``true`` if > +the clock state was modified; that is, if the multiplier or the diviser > +or both were changed by the call. > + > Note that ``clock_set_mul_div()`` does not automatically call > ``clock_propagate()``. If you make a runtime change to the > multiplier or divider you must call clock_propagate() yourself. > diff --git a/include/hw/clock.h b/include/hw/clock.h > index bb12117f67..eb58599131 100644 > --- a/include/hw/clock.h > +++ b/include/hw/clock.h > @@ -357,6 +357,8 @@ char *clock_display_freq(Clock *clk); > * @multiplier: multiplier value > * @divider: divider value > * > + * @return: true if the clock is changed. > + * > * By default, a Clock's children will all run with the same period > * as their parent. This function allows you to adjust the multiplier > * and divider used to derive the child clock frequency. > @@ -374,6 +376,6 @@ char *clock_display_freq(Clock *clk); > * Note that this function does not call clock_propagate(); the > * caller should do that if necessary. > */ > -void clock_set_mul_div(Clock *clk, uint32_t multiplier, uint32_t divider= ); > +bool clock_set_mul_div(Clock *clk, uint32_t multiplier, uint32_t divider= ); > > #endif /* QEMU_HW_CLOCK_H */ > diff --git a/hw/core/clock.c b/hw/core/clock.c > index d82e44cd1a..a19c7db7df 100644 > --- a/hw/core/clock.c > +++ b/hw/core/clock.c > @@ -143,14 +143,20 @@ char *clock_display_freq(Clock *clk) > return freq_to_str(clock_get_hz(clk)); > } > > -void clock_set_mul_div(Clock *clk, uint32_t multiplier, uint32_t divider= ) > +bool clock_set_mul_div(Clock *clk, uint32_t multiplier, uint32_t divider= ) > { > assert(divider !=3D 0); > > + if (clk->multiplier =3D=3D multiplier && clk->divider =3D=3D divider= ) { > + return false; > + } > + > trace_clock_set_mul_div(CLOCK_PATH(clk), clk->multiplier, multiplier= , > clk->divider, divider); > clk->multiplier =3D multiplier; > clk->divider =3D divider; > + > + return true; > } > > static void clock_initfn(Object *obj) > -- > 2.41.0 > >