Re: [PATCH v6 11/11] arm64: dts: ti: k3-am64: Reserve timers used by MCU FW

[Judith Mendez]

Hi Andrew,

On 4/7/25 7:35 AM, Andrew Davis wrote:
> On 4/4/25 7:15 PM, Judith Mendez wrote:
> > From: Hari Nagalla <hnagalla@xxxxxx>
> >
> > AM64x device has 4 R5F cores in the main domain. TI MCU firmware uses
> > main domain timers as tick timers in these firmwares. Hence keep them
> > as reserved in the Linux device tree.
> >
> > Signed-off-by: Hari Nagalla <hnagalla@xxxxxx>
> > Signed-off-by: Judith Mendez <jm@xxxxxx>
> > ---
> >   arch/arm64/boot/dts/ti/k3-am642-evm.dts | 17 +++++++++++++++++
> >   arch/arm64/boot/dts/ti/k3-am642-sk.dts  | 17 +++++++++++++++++
> >   2 files changed, 34 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/ti/k3-am642-evm.dts 
> > b/arch/arm64/boot/dts/ti/k3-am642-evm.dts
> > index f8ec40523254b..68bd6b806f8f0 100644
> > --- a/arch/arm64/boot/dts/ti/k3-am642-evm.dts
> > +++ b/arch/arm64/boot/dts/ti/k3-am642-evm.dts
> > @@ -796,6 +796,23 @@ &mcu_m4fss {
> >       status = "okay";
> >   };
> > +/* main_timers 8-11 are used by TI MCU FW */
>
> Can you make this comment per-core and explain which core
> each timer is reserved for? Makes it easier on me in Zephyr
> to point out why we use the timers that we do, something
> like:
>
> /* main_timer8 is reserved for mcu_r5fss0_core0 */

Sure, I can do that. Will wait for [0] conversation to close and then
respin the series with this change

[0] 
https://lore.kernel.org/linux-devicetree/f42607f5-e39d-48a1-89c0-11d4982a2426@xxxxxx/

~ Judith

> Andrew
>
> > +&main_timer8 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer9 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer10 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer11 {
> > +    status = "reserved";
> > +};
> > +
> >   &serdes_ln_ctrl {
> >       idle-states = <AM64_SERDES0_LANE0_PCIE0>;
> >   };
> > diff --git a/arch/arm64/boot/dts/ti/k3-am642-sk.dts 
> > b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> > index 33e421ec18abb..07fbdf2400d23 100644
> > --- a/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> > +++ b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> > @@ -710,6 +710,23 @@ &mcu_m4fss {
> >       status = "okay";
> >   };
> > +/* main_timers 8-11 are used by TI MCU FW */
> > +&main_timer8 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer9 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer10 {
> > +    status = "reserved";
> > +};
> > +
> > +&main_timer11 {
> > +    status = "reserved";
> > +};
> > +
> >   &ecap0 {
> >       status = "okay";
> >       /* PWM is available on Pin 1 of header J3 */