Baikal-T1 SoC is equipped with an embedded process, voltage and temperature sensor to monitor the chip internal environment like temperature, supply voltage and transistors performance. This bindings describes the external Baikal-T1 PVT control interfaces like MMIO registers space, interrupt request number and clocks source. These are then used by the corresponding hwmon device driver to implement the sysfs files-based access to the sensors functionality. Co-developed-by: Maxim Kaurkin <maxim.kaurkin@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Maxim Kaurkin <maxim.kaurkin@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> Reviewed-by: Rob Herring <robh@xxxxxxxxxx> Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx --- Changelog v2: - Lowercase the node-name in the example. - Add dual-license header. - Don't use a multi-arg clock phandle reference in the examples dt-binding property. Thus reundant include pre-processor statement can be removed. - Replace "additionalProperties: false" property with "unevaluatedProperties: false". - Discard label definition from the example. - Align settings of the "#thermal-sensor-cells" property with two spaces ahead of the property line start. Changelog v3: - Add "baikal,pvt-temp-trim-millicelsius" property support. Changelog v4: - Rename the "baikal,pvt-temp-trim-millicelsius" property to "baikal,pvt-temp-offset-millicelsius". --- .../bindings/hwmon/baikal,bt1-pvt.yaml | 107 ++++++++++++++++++ 1 file changed, 107 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/baikal,bt1-pvt.yaml diff --git a/Documentation/devicetree/bindings/hwmon/baikal,bt1-pvt.yaml b/Documentation/devicetree/bindings/hwmon/baikal,bt1-pvt.yaml new file mode 100644 index 000000000000..84ae4cdd08ed --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/baikal,bt1-pvt.yaml @@ -0,0 +1,107 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +# Copyright (C) 2020 BAIKAL ELECTRONICS, JSC +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/hwmon/baikal,bt1-pvt.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Baikal-T1 PVT Sensor + +maintainers: + - Serge Semin <fancer.lancer@xxxxxxxxx> + +description: | + Baikal-T1 SoC provides an embedded process, voltage and temperature + sensor to monitor an internal SoC environment (chip temperature, supply + voltage and process monitor) and on time detect critical situations, + which may cause the system instability and even damages. The IP-block + is based on the Analog Bits PVT sensor, but is equipped with a dedicated + control wrapper, which provides a MMIO registers-based access to the + sensor core functionality (APB3-bus based) and exposes an additional + functions like thresholds/data ready interrupts, its status and masks, + measurements timeout. Its internal structure is depicted on the next + diagram: + + Analog Bits core Bakal-T1 PVT control block + +--------------------+ +------------------------+ + | Temperature sensor |-+ +------| Sensors control | + |--------------------| |<---En---| |------------------------| + | Voltage sensor |-|<--Mode--| +--->| Sampled data | + |--------------------| |<--Trim--+ | |------------------------| + | Low-Vt sensor |-| | +--| Thresholds comparator | + |--------------------| |---Data----| | |------------------------| + | High-Vt sensor |-| | +->| Interrupts status | + |--------------------| |--Valid--+-+ | |------------------------| + | Standard-Vt sensor |-+ +---+--| Interrupts mask | + +--------------------+ |------------------------| + ^ | Interrupts timeout | + | +------------------------+ + | ^ ^ + Rclk-----+----------------------------------------+ | + APB3-------------------------------------------------+ + + This bindings describes the external Baikal-T1 PVT control interfaces + like MMIO registers space, interrupt request number and clocks source. + These are then used by the corresponding hwmon device driver to + implement the sysfs files-based access to the sensors functionality. + +properties: + compatible: + const: baikal,bt1-pvt + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + clocks: + items: + - description: PVT reference clock + - description: APB3 interface clock + + clock-names: + items: + - const: ref + - const: pclk + + "#thermal-sensor-cells": + description: Baikal-T1 can be referenced as the CPU thermal-sensor + const: 0 + + baikal,pvt-temp-offset-millicelsius: + description: | + Temperature sensor trimming factor. It can be used to manually adjust the + temperature measurements within 7.130 degrees Celsius. + maxItems: 1 + items: + default: 0 + minimum: 0 + maximum: 7130 + +unevaluatedProperties: false + +required: + - compatible + - reg + - interrupts + - clocks + - clock-names + +examples: + - | + #include <dt-bindings/interrupt-controller/mips-gic.h> + + pvt@1f200000 { + compatible = "baikal,bt1-pvt"; + reg = <0x1f200000 0x1000>; + #thermal-sensor-cells = <0>; + + interrupts = <GIC_SHARED 31 IRQ_TYPE_LEVEL_HIGH>; + + baikal,pvt-temp-trim-millicelsius = <1000>; + + clocks = <&ccu_sys>, <&ccu_sys>; + clock-names = "ref", "pclk"; + }; +... -- 2.26.2