Re: [PATCH v3 2/2] arm64: dts: ti: k3-am62p-j722s-common-main: Add HSM M4F node

[Kumar, Udit]

On 1/15/2026 11:23 AM, Padhi, Beleswar wrote:
> On 1/15/2026 11:16 AM, Kumar, Udit wrote:
> > On 1/15/2026 11:11 AM, Padhi, Beleswar wrote:
> > > Hi Udit,
> > >
> > > On 1/15/2026 10:06 AM, Kumar, Udit wrote:
> > > > Hi Beleswar,
> > > >
> > > > On 1/14/2026 11:05 PM, Beleswar Padhi wrote:
> > > > > The TI K3 AM62P and J722S SoCs have a HSM (High Security Module) M4F
> > > > > core in the MAIN Voltage Domain which could be used to run secure
> > > > > services like Authentication. Add Device Tree Node definitions for 
> > > > > the
> > > > > HSM core in the respective SoC common main dtsi file.
> > > > >
> > > > > The HSM node is reserved to be loaded and booted by the early-stage
> > > > > bootloader. The firmware-name property is defined at the SoC level
> > > > > since the HSM is not a general-purpose remote core and boards are
> > > > > unlikely to use separate firmware. If needed in exceptional cases,
> > > > > board-specific device trees can override this property.
> > > > >
> > > > > The corresponding reg ranges of HSM node has also been added to its
> > > > > parent node's (cbass_main bus) ranges property.
> > > > >
> > > > > Signed-off-by: Beleswar Padhi <b-padhi@xxxxxx>
> > > > > ---
> > > > > v3: Changelog:
> > > > > [Nishanth]:
> > > > >   1. Use generic node name 'remoteproc'
> > > > >   2. Use label 'hsm' instead of 'hsm_m4fss'
> > > > >   3. Add a comment for separate SRAMs
> > > > >   4. Update firmware-name property to match existing naming 
> > > > > conventions
> > > > >   5. Change status to 'reserved' and add a commment
> > > > >   6. Re-order bootph-pre-ram property before vendor properties
> > > > >   7. Update commit msg adding rationale for firmware-name in SoC.dtsi
> > > > >
> > > > > Link to v2:
> > > > > https://lore.kernel.org/all/20260106104755.948086-4-b-padhi@xxxxxx/
> > > > >
> > > > > v2: Changelog:
> > > > > 1. None
> > > > >
> > > > > Link to v1:
> > > > > https://lore.kernel.org/all/20251231165102.950644-4-b-padhi@xxxxxx/
> > > > >
> > > > >   .../boot/dts/ti/k3-am62p-j722s-common-main.dtsi | 17 
> > > > > +++++++++++++++++
> > > > >   arch/arm64/boot/dts/ti/k3-am62p.dtsi            |  1 +
> > > > >   arch/arm64/boot/dts/ti/k3-j722s-main.dtsi       |  5 +++++
> > > > >   arch/arm64/boot/dts/ti/k3-j722s.dtsi            |  1 +
> > > > >   4 files changed, 24 insertions(+)
> > > > >
> > > > > diff --git 
> > > > > a/arch/arm64/boot/dts/ti/k3-am62p-j722s-common-main.dtsi 
> > > > > b/arch/arm64/boot/dts/ti/k3-am62p-j722s-common-main.dtsi
> > > > > index 3cf7c2b3ce2dd..0e1af2a69ca2e 100644
> > > > > --- a/arch/arm64/boot/dts/ti/k3-am62p-j722s-common-main.dtsi
> > > > > +++ b/arch/arm64/boot/dts/ti/k3-am62p-j722s-common-main.dtsi
> > > > > @@ -1117,4 +1117,21 @@ vpu: video-codec@30210000 {
> > > > >           clocks = <&k3_clks 204 2>;
> > > > >           power-domains = <&k3_pds 204 TI_SCI_PD_EXCLUSIVE>;
> > > > >       };
> > > > > +
> > > > > +    hsm: remoteproc@43c00000 {
> > > > > +        compatible = "ti,hsm-m4fss";
> > > > > +        /* contiguous regions but instantiated separately in HW */
> > > > > +        reg = <0x00 0x43c00000 0x00 0x20000>,
> > > > > +              <0x00 0x43c20000 0x00 0x10000>,
> > > > > +              <0x00 0x43c30000 0x00 0x10000>;
> > > > > +        reg-names = "sram0_0", "sram0_1", "sram1";
> > > > > +        resets = <&k3_reset 225 1>;
> > > > > +        firmware-name = "am62p-hsm-m4f-fw";
> > > >
> > > > you don't need clock and power-domain for this ?
> > >
> > >
> > > That info is abstracted out via ti-sci calls. ti_sci_cmd_get_device()
> > > takes care of setting clocks and power domains for us.
> > >
> > > Same for other rprocs:
> > > https://github.com/torvalds/linux/blob/master/arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi#L178 
> >
> >
> > Is this specific handling for m4 core ? 
>
>
> For all single cores like M4, DSP, R5F0_0/R5F0_1 etc.

Ok


> > , I see other rproc got power at cluster level
>
>
> We don't make any ti-sci calls for the cluster level, which is why we
> need that info here in DT. Otherwise, ti-sci calls take care of the
> individual cores for us. That's why R5F child cores don't have
> power domain info in the DT:
> https://github.com/torvalds/linux/blob/master/arch/arm64/boot/dts/ti/k3-j7200-main.dtsi#L1521-L1535 

R5 cores are inside cluster , it is be better to handle core and cluster 
in same way.

But this patch is not related to R5.

So

Reviewed-by: Udit Kumar <u-kumar1@xxxxxx>


> Thanks,
> Beleswar
>
> > https://github.com/torvalds/linux/blob/master/arch/arm64/boot/dts/ti/k3-j7200-main.dtsi#L1518 
> >
> >
> >
> > > Thanks,
> > > Beleswar
> > >
> > > > > +        bootph-pre-ram;
> > > > > +        ti,sci = <&dmsc>;
> > > > > +        ti,sci-dev-id = <225>;
> > > > > +        ti,sci-proc-ids = <0x80 0xff>;
> > > > > +        /* reserved for early-stage bootloader */
> > > > > +        status = "reserved";
> > > > > +    };
> > > > >   };
> > > > > diff --git a/arch/arm64/boot/dts/ti/k3-am62p.dtsi 
> > > > > b/arch/arm64/boot/dts/ti/k3-am62p.dtsi
> > > > > index e2c01328eb298..9d6266d6ddb82 100644
> > > > > --- a/arch/arm64/boot/dts/ti/k3-am62p.dtsi
> > > > > +++ b/arch/arm64/boot/dts/ti/k3-am62p.dtsi
> > > > > @@ -96,6 +96,7 @@ cbass_main: bus@f0000 {
> > > > >                <0x00 0x31100000 0x00 0x31100000 0x00 0x00050000>, 
> > > > > /* USB1 DWC3 Core window */
> > > > >                <0x00 0x40900000 0x00 0x40900000 0x00 0x00030000>, 
> > > > > /* SA3UL */
> > > > > [..]