Add nvmem-syscon subnode to expose TAMP_BKPxR register 19 to user space.
This register contains U-Boot boot counter, by exposing it to user space
the user space can reset the boot counter.
Read access example:
"
$ hexdump -vC /sys/bus/nvmem/devices/5c00a000.tamp\:nvmem0/nvmem
00000000 0c 00 c4 b0
"
Signed-off-by: Marek Vasut <marex@xxxxxxx>
---
Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>
Cc: Rafał Miłecki <rafal@xxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
To: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
---
arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi | 11 +++++++++++
arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi | 11 +++++++++++
2 files changed, 22 insertions(+)
diff --git a/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi b/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi
index 155843e1402fb..8277837be8a51 100644
--- a/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi
+++ b/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi
@@ -533,6 +533,17 @@ &sdmmc3 {
status = "okay";
};
+&tamp {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /* Boot counter */
+ nvmem {
+ compatible = "nvmem-syscon";
+ reg = <0x14c 0x4>;
+ };
+};
+
&uart4 {
pinctrl-names = "default";
pinctrl-0 = <&uart4_pins_a>;
diff --git a/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi b/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi
index 134a798ad3f23..42a8d5cdd7024 100644
--- a/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi
+++ b/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi
@@ -271,3 +271,14 @@ &rng1 {
&rtc {
status = "okay";
};
+
+&tamp {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /* Boot counter */
+ nvmem {
+ compatible = "nvmem-syscon";
+ reg = <0x14c 0x4>;
+ };
+};
--
2.35.1
