[PATCH 1/3] dt-bindings: nvmem: add binding for STM32MPX TAMP backup registers

From: Patrice Chotard

Date: Thu Sep 10 2026 - 10:34:20 EST


From: Simeon Marijon <simeon.marijon@xxxxxxxxxxx>

Adds the binding documentation for TAMP backup registers.
The backup registers is a part of the TAMP device of STM32 MPU.

Signed-off-by: Simeon Marijon <simeon.marijon@xxxxxxxxxxx>
Signed-off-by: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
---
.../bindings/nvmem/st,stm32-tamp-nvram.yaml | 57 ++++++++++++++++++++++
MAINTAINERS | 7 +++
2 files changed, 64 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml b/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
new file mode 100644
index 000000000000..4af3b88db566
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/nvmem/st,stm32-tamp-nvram.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics STM32 backup registers as NVMEM
+
+description: |
+ This represents STM32 backup registers area presented as nvmem cells.
+ This contains various information (e.g. boot mode passed to bootloaders).
+
+maintainers:
+ - Simeon Marijon <simeon.marijon@xxxxxxxxxxx>
+ - Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
+
+allOf:
+ - $ref: nvmem.yaml#
+
+properties:
+ compatible:
+ enum:
+ - st,stm32mp15-tamp-nvram
+ - st,stm32mp25-tamp-nvram
+
+ reg:
+ description:
+ TAMP Registers bank location and size.
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ nvram: nvram@5c00a100 {
+ reg = <0x5c00a100 0x80>;
+ compatible = "st,stm32mp15-tamp-nvram";
+
+ nvmem-layout {
+ compatible = "fixed-layout";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /* Data cells */
+ wakeup_sec: tamp-bkp@0 {
+ reg = <0x0 0x4>;
+ };
+ boot_mode: tamp-bkp@50 {
+ /*see boot mode selection feature*/
+ reg = <0x50 0x4>;
+ };
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 3a19da74d00c..b634c037c229 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -26261,6 +26261,13 @@ F: Documentation/arch/arm/stm32/stm32-dma-mdma-chaining.rst
F: Documentation/devicetree/bindings/dma/stm32/
F: drivers/dma/stm32/

+STM32 TAMP DRIVERS
+M: Simeon Marijon <simeon.marijon@xxxxxxxxxxx>
+M: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
+L: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx (moderated for non-subscribers)
+S: Maintained
+F: Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
+
STM32 TIMER/LPTIMER DRIVERS
M: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
S: Maintained

--
2.43.0