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: Conor Dooley <conor+dt@xxxxxxxxxx> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx> Cc: Marek Vasut <marex@xxxxxxx> Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx> Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> Cc: devicetree@xxxxxxxxxxxxxxx Cc: kernel@xxxxxxxxxxxxxxxxxx Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx --- V2: No change --- 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 74735552f4803..b2557bb718f52 100644 --- a/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi +++ b/arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi @@ -537,6 +537,17 @@ &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 bba19f21e5277..864960387e634 100644 --- a/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi +++ b/arch/arm/boot/dts/stm32mp15xx-dhcor-som.dtsi @@ -269,3 +269,14 @@ &rng1 { &rtc { status = "okay"; }; + +&tamp { + #address-cells = <1>; + #size-cells = <1>; + + /* Boot counter */ + nvmem { + compatible = "nvmem-syscon"; + reg = <0x14c 0x4>; + }; +}; -- 2.39.2