diff mbox series

[2/2] arm64: dts: st: add TAMP-NVRAM support for STM32MP25

Message ID 20260107194541.1843999-2-dario.binacchi@amarulasolutions.com
State New
Headers
Series [1/2] dt-bindings: nvmem: add STM32 TAMP NVRAM |

Commit Message

Dario Binacchi Jan. 7, 2026, 7:45 p.m. UTC 
Add the TAMP node along with its NVRAM child node and define the
fixed-layout for fwu_info and boot_mode registers.

The TAMP (Tamper and backup registers) block is a system controller that
provides access to backup registers as NVMEM storage that persists across
reboots.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

---

 arch/arm64/boot/dts/st/stm32mp251.dtsi | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

Comments

Patrice CHOTARD Jan. 9, 2026, 10:40 a.m. UTC | #1 
On 1/7/26 20:45, Dario Binacchi wrote:
> Add the TAMP node along with its NVRAM child node and define the
> fixed-layout for fwu_info and boot_mode registers.
> 
> The TAMP (Tamper and backup registers) block is a system controller that
> provides access to backup registers as NVMEM storage that persists across
> reboots.
> 
> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> 
> ---
> 
>  arch/arm64/boot/dts/st/stm32mp251.dtsi | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/st/stm32mp251.dtsi b/arch/arm64/boot/dts/st/stm32mp251.dtsi
> index a8e6e0f77b83..c7839e732f31 100644
> --- a/arch/arm64/boot/dts/st/stm32mp251.dtsi
> +++ b/arch/arm64/boot/dts/st/stm32mp251.dtsi
> @@ -2084,6 +2084,32 @@ rtc: rtc@46000000 {
>  			status = "disabled";
>  		};
>  
> +		tamp: tamp@46010000 {
> +			compatible = "st,stm32-tamp", "syscon", "simple-mfd";
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			reg = <0x46010000 0x400>;
> +			ranges;
> +
> +			nvram: nvram@46010100 {
> +				compatible = "st,stm32mp25-tamp-nvram";
> +				reg = <0x46010100 0x200>;
> +				nvmem-layout {
> +					compatible = "fixed-layout";
> +					#address-cells = <1>;
> +					#size-cells = <1>;
> +
> +					fwu_info: tamp-bkp@c0 {
> +						reg = <0xc0 0x4>;
> +					};
> +
> +					boot_mode: tamp-bkp@180 {
> +						reg = <0x180 0x4>;
> +					};
> +				};
> +			};
> +		};
> +
>  		pinctrl_z: pinctrl@46200000 {
>  			#address-cells = <1>;
>  			#size-cells = <1>;
Hi Dario

At STMicroelectronics we intend to upstream tamp-vram driver for STM32MP series.
If you don't see any objection, we prefer to manage it in our side.

Thanks
Patrice

To unsubscribe from this group and stop receiving emails from it, send an email to linux-amarula+unsubscribe@amarulasolutions.com.
Dario Binacchi Jan. 11, 2026, 3:20 p.m. UTC | #2 
Hello Patrice,

On Fri, Jan 9, 2026 at 11:40 AM Patrice CHOTARD
<patrice.chotard@foss.st.com> wrote:
>
>
>
> On 1/7/26 20:45, Dario Binacchi wrote:
> > Add the TAMP node along with its NVRAM child node and define the
> > fixed-layout for fwu_info and boot_mode registers.
> >
> > The TAMP (Tamper and backup registers) block is a system controller that
> > provides access to backup registers as NVMEM storage that persists across
> > reboots.
> >
> > Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> >
> > ---
> >
> >  arch/arm64/boot/dts/st/stm32mp251.dtsi | 26 ++++++++++++++++++++++++++
> >  1 file changed, 26 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/st/stm32mp251.dtsi b/arch/arm64/boot/dts/st/stm32mp251.dtsi
> > index a8e6e0f77b83..c7839e732f31 100644
> > --- a/arch/arm64/boot/dts/st/stm32mp251.dtsi
> > +++ b/arch/arm64/boot/dts/st/stm32mp251.dtsi
> > @@ -2084,6 +2084,32 @@ rtc: rtc@46000000 {
> >                       status = "disabled";
> >               };
> >
> > +             tamp: tamp@46010000 {
> > +                     compatible = "st,stm32-tamp", "syscon", "simple-mfd";
> > +                     #address-cells = <1>;
> > +                     #size-cells = <1>;
> > +                     reg = <0x46010000 0x400>;
> > +                     ranges;
> > +
> > +                     nvram: nvram@46010100 {
> > +                             compatible = "st,stm32mp25-tamp-nvram";
> > +                             reg = <0x46010100 0x200>;
> > +                             nvmem-layout {
> > +                                     compatible = "fixed-layout";
> > +                                     #address-cells = <1>;
> > +                                     #size-cells = <1>;
> > +
> > +                                     fwu_info: tamp-bkp@c0 {
> > +                                             reg = <0xc0 0x4>;
> > +                                     };
> > +
> > +                                     boot_mode: tamp-bkp@180 {
> > +                                             reg = <0x180 0x4>;
> > +                                     };
> > +                             };
> > +                     };
> > +             };
> > +
> >               pinctrl_z: pinctrl@46200000 {
> >                       #address-cells = <1>;
> >                       #size-cells = <1>;
> Hi Dario
>
> At STMicroelectronics we intend to upstream tamp-vram driver for STM32MP series.
> If you don't see any objection, we prefer to manage it in our side.

Ok, no problems.

Thanks and regards,
Dario
>
> Thanks
> Patrice
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/st/stm32mp251.dtsi b/arch/arm64/boot/dts/st/stm32mp251.dtsi
index a8e6e0f77b83..c7839e732f31 100644
--- a/arch/arm64/boot/dts/st/stm32mp251.dtsi
+++ b/arch/arm64/boot/dts/st/stm32mp251.dtsi
@@ -2084,6 +2084,32 @@  rtc: rtc@46000000 {
 			status = "disabled";
 		};
 
+		tamp: tamp@46010000 {
+			compatible = "st,stm32-tamp", "syscon", "simple-mfd";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			reg = <0x46010000 0x400>;
+			ranges;
+
+			nvram: nvram@46010100 {
+				compatible = "st,stm32mp25-tamp-nvram";
+				reg = <0x46010100 0x200>;
+				nvmem-layout {
+					compatible = "fixed-layout";
+					#address-cells = <1>;
+					#size-cells = <1>;
+
+					fwu_info: tamp-bkp@c0 {
+						reg = <0xc0 0x4>;
+					};
+
+					boot_mode: tamp-bkp@180 {
+						reg = <0x180 0x4>;
+					};
+				};
+			};
+		};
+
 		pinctrl_z: pinctrl@46200000 {
 			#address-cells = <1>;
 			#size-cells = <1>;