Re: [PATCH 1/2] dt-bindings: hwmon: Add Baikal-T1 PVT sensor bindings

[Rob Herring <robh@kernel.org>]

On Fri, Mar 06, 2020 at 04:26:03PM +0300, Sergey.Semin@baikalelectronics.ru wrote:
> From: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> 
> 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.
> 
> Signed-off-by: Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: Paul Burton <paulburton@kernel.org>
> Cc: Ralf Baechle <ralf@linux-mips.org>
> ---
>  .../devicetree/bindings/hwmon/be,bt1-pvt.yaml | 100 ++++++++++++++++++
>  1 file changed, 100 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/be,bt1-pvt.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/be,bt1-pvt.yaml b/Documentation/devicetree/bindings/hwmon/be,bt1-pvt.yaml
> new file mode 100644
> index 000000000000..d575d124d538
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/be,bt1-pvt.yaml
> @@ -0,0 +1,100 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license

> +#
> +# Copyright (C) 2019 BAIKAL ELECTRONICS, JSC
> +#
> +# Baikal-T1 Process, Voltage, Temperature Sensor Device Tree Bindings.

drop

> +#
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/be,bt1-pvt.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Baikal-T1 PVT Sensor Device Tree Bindings
> +
> +maintainers:
> +  - Serge Semin <fancer.lancer@gmail.com>
> +
> +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: be,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
> +
> +additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/mips-gic.h>
> +    #include <dt-bindings/clock/bt1-ccu.h>
> +
> +    pvt: pvt@1F200000 {

lowercase hex

> +      compatible = "be,bt1-pvt";
> +      reg = <0x1F200000 0x1000>;
> +      #thermal-sensor-cells = <0>;
> +
> +      interrupts = <GIC_SHARED 31 IRQ_TYPE_LEVEL_HIGH>;
> +
> +      clocks = <&ccu_sys CCU_SYS_PVT_CLK>,
> +               <&ccu_sys CCU_SYS_APB_CLK>;
> +      clock-names = "ref", "pclk";
> +    };
> +...
> -- 
> 2.25.1
>