Re: [PATCH v5 3/4] dt-bindings: iio: adc: Add Xilinx AMS binding documentation

From: Rob Herring
Date: Tue Jun 01 2021 - 16:24:20 EST


On Fri, May 28, 2021 at 06:29:58PM +0100, Anand Ashok Dumbre wrote:
> Xilinx AMS have several ADC channels that can be used for measurement of
> different voltages and temperatures. Document the same in the bindings.
>
> Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xxxxxxxxxx>
> ---
> .../bindings/iio/adc/xlnx,zynqmp-ams.yaml | 265 ++++++++++++++++++
> 1 file changed, 265 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/xlnx,zynqmp-ams.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/xlnx,zynqmp-ams.yaml b/Documentation/devicetree/bindings/iio/adc/xlnx,zynqmp-ams.yaml
> new file mode 100644
> index 000000000000..df3cfca69e2d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/xlnx,zynqmp-ams.yaml
> @@ -0,0 +1,265 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/xlnx,zynqmp-ams.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Xilinx Zynq Ultrascale AMS controller
> +
> +maintainers:
> + - Anand Ashok Dumbre <anand.ashok.dumbre@xxxxxxxxxx>
> +
> +description: |
> + The AMS (Analog Monitoring System) includes an ADC as well as on-chip sensors
> + that can be used to sample external voltages and monitor on-die operating
> + conditions, such as temperature and supply voltage levels.
> + The AMS has two SYSMON blocks which are PL (Programmable Logic) SYSMON and
> + PS (Processing System) SYSMON.
> + All designs should have AMS registers, but PS and PL are optional. The
> + AMS controller can work with only PS, only PL and both PS and PL
> + configurations. Please specify registers according to your design. Devicetree
> + should always have AMS module property. Providing PS & PL module is optional.
> +
> + AMS Channel Details
> + ```````````````````
> + Sysmon Block |Channel| Details |Measurement
> + |Number | |Type

Use spaces rather than tabs

> + ---------------------------------------------------------------------------------------------------------
> + AMS CTRL |0 |System PLLs voltage measurement, VCC_PSPLL. |Voltage
> + |1 |Battery voltage measurement, VCC_PSBATT. |Voltage
> + |2 |PL Internal voltage measurement, VCCINT. |Voltage
> + |3 |Block RAM voltage measurement, VCCBRAM. |Voltage
> + |4 |PL Aux voltage measurement, VCCAUX. |Voltage
> + |5 |Voltage measurement for six DDR I/O PLLs, VCC_PSDDR_PLL. |Voltage
> + |6 |VCC_PSINTFP_DDR voltage measurement. |Voltage
> + ---------------------------------------------------------------------------------------------------------
> + PS Sysmon |7 |LPD temperature measurement. |Temperature
> + |8 |FPD temperature measurement (REMOTE). |Temperature
> + |9 |VCC PS LPD voltage measurement (supply1). |Voltage
> + |10 |VCC PS FPD voltage measurement (supply2). |Voltage
> + |11 |PS Aux voltage reference (supply3). |Voltage
> + |12 |DDR I/O VCC voltage measurement. |Voltage
> + |13 |PS IO Bank 503 voltage measurement (supply5). |Voltage
> + |14 |PS IO Bank 500 voltage measurement (supply6). |Voltage
> + |15 |VCCO_PSIO1 voltage measurement. |Voltage
> + |16 |VCCO_PSIO2 voltage measurement. |Voltage
> + |17 |VCC_PS_GTR voltage measurement (VPS_MGTRAVCC). |Voltage
> + |18 |VTT_PS_GTR voltage measurement (VPS_MGTRAVTT). |Voltage
> + |19 |VCC_PSADC voltage measurement. |Voltage
> + ---------------------------------------------------------------------------------------------------------
> + PL Sysmon |20 |PL temperature measurement. |Temperature
> + |21 |PL Internal voltage measurement, VCCINT. |Voltage
> + |22 |PL Auxiliary voltage measurement, VCCAUX. |Voltage
> + |23 |ADC Reference P+ voltage measurement. |Voltage
> + |24 |ADC Reference N- voltage measurement. |Voltage
> + |25 |PL Block RAM voltage measurement, VCCBRAM. |Voltage
> + |26 |LPD Internal voltage measurement, VCC_PSINTLP (supply4). |Voltage
> + |27 |FPD Internal voltage measurement, VCC_PSINTFP (supply5). |Voltage
> + |28 |PS Auxiliary voltage measurement (supply6). |Voltage
> + |29 |PL VCCADC voltage measurement (vccams). |Voltage
> + |30 |Differential analog input signal voltage measurment. |Voltage
> + |31 |VUser0 voltage measurement (supply7). |Voltage
> + |32 |VUser1 voltage measurement (supply8). |Voltage
> + |33 |VUser2 voltage measurement (supply9). |Voltage
> + |34 |VUser3 voltage measurement (supply10). |Voltage
> + |35 |Auxiliary ch 0 voltage measurement (VAux0). |Voltage
> + |36 |Auxiliary ch 1 voltage measurement (VAux1). |Voltage
> + |37 |Auxiliary ch 2 voltage measurement (VAux2). |Voltage
> + |38 |Auxiliary ch 3 voltage measurement (VAux3). |Voltage
> + |39 |Auxiliary ch 4 voltage measurement (VAux4). |Voltage
> + |40 |Auxiliary ch 5 voltage measurement (VAux5). |Voltage
> + |41 |Auxiliary ch 6 voltage measurement (VAux6). |Voltage
> + |42 |Auxiliary ch 7 voltage measurement (VAux7). |Voltage
> + |43 |Auxiliary ch 8 voltage measurement (VAux8). |Voltage
> + |44 |Auxiliary ch 9 voltage measurement (VAux9). |Voltage
> + |45 |Auxiliary ch 10 voltage measurement (VAux10). |Voltage
> + |46 |Auxiliary ch 11 voltage measurement (VAux11). |Voltage
> + |47 |Auxiliary ch 12 voltage measurement (VAux12). |Voltage
> + |48 |Auxiliary ch 13 voltage measurement (VAux13). |Voltage
> + |49 |Auxiliary ch 14 voltage measurement (VAux14). |Voltage
> + |50 |Auxiliary ch 15 voltage measurement (VAux15). |Voltage
> + --------------------------------------------------------------------------------------------------------
> +
> +properties:
> + compatible:
> + enum:
> + - xlnx,zynqmp-ams
> +
> + interrupts:
> + description: IRQ line for AMS

Drop.

> + maxItems: 1
> +
> + interrupt-names:
> + items:
> + - const: ams-irq

Kind of a pointless name. You don't need *-names unless you have more
than one.

> +
> + reg:
> + description: AMS Controller register space
> + maxItems: 1
> +
> + reg-names:
> + items:
> + - const: ams-base
> +
> + ranges:
> + description:
> + Keep the property empty to map child address space
> + (for PS and/or PL) nodes 1:1 onto the parent address space.
> + maxItems: 1

This contradicts 'empty'.

> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 1
> +
> + '#io-channel-cells':
> + const: 1
> +
> +patternProperties:
> + "^ams-ps@0,0$":

If you have a non standard unit-address, you need to define the fields.

> + type: object
> + description: |
> + PS (Processing System) SYSMON is memory mapped to PS. This block has
> + built-in alarm generation logic that is used to interrupt the processor
> + based on condition set.
> +
> + properties:
> + compatible:
> + enum:
> + - xlnx,zynqmp-ams-ps
> +
> + reg:
> + description: Register Space for PS-SYSMON
> + maxItems: 1
> +
> + required:
> + - compatible
> + - reg
> +
> + additionalProperties: false
> +
> + "^ams-pl@1,0$":

What does the '1' correspond to?

> + type: object
> + description:
> + PL-SYSMON is capable of monitoring off chip voltage and temperature.
> + PL-SYSMON block has DRP, JTAG and I2C interface to enable monitoring
> + from external master. Out of this interface currently only DRP is
> + supported. This block has alarm generation logic that is used to
> + interrupt the processor based on condition set.
> +
> + properties:
> + compatible:
> + items:
> + - enum:
> + - xlnx,zynqmp-ams-pl
> +
> + reg:
> + description: Register Space for PL-SYSMON.
> + maxItems: 1
> +
> + required:
> + - compatible
> + - reg
> +
> + additionalProperties: false
> +
> + patternProperties:
> + "^xlnx,ext-channels$":

Not a pattern. Put under 'properties'.

> +
> + type: object
> +
> + description:
> + List of external channels that are connected to the AMS PL module.
> + If this property is not present, no external channels will be
> + assumed to be connected.
> +
> + properties:
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + additionalProperties: false
> +
> + patternProperties:
> + "^channel@([0-9]{1,2}|1[0-5][0-9])$":
> + type: object
> + description:
> + Describes the external channels connected.
> +
> + properties:
> + reg:
> + $ref: /schemas/types.yaml#/definitions/uint32

'reg' already has a type.

> + description:
> + Pair of pins the channel is connected to. This value is
> + same as Channel Number for a particular channel.
> + minimum: 20
> + maximum: 50

Based on the unit-address, the max is 159.

> +
> + xlnx,bipolar:
> + $ref: /schemas/types.yaml#/definitions/flag
> + type: boolean
> + description:
> + If the set channel is used in bipolar mode.
> +
> + required:
> + - reg
> +
> + additionalProperties: false
> +
> +required:
> + - compatible
> + - interrupts
> + - interrupt-names
> + - reg
> + - reg-names
> + - ranges
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + bus {
> + #address-cells = <2>;
> + #size-cells = <2>;
> +
> + xilinx_ams: ams@ffa50000 {
> + compatible = "xlnx,zynqmp-ams";
> + interrupt-parent = <&gic>;
> + interrupts = <0 56 4>;
> + interrupt-names = "ams-irq";
> + reg = <0x0 0xffa50000 0x0 0x800>;
> + reg-names = "ams-base";
> + #address-cells = <1>;
> + #size-cells = <1>;
> + #io-channel-cells = <1>;
> + ranges = <0 0 0xffa50800 0x800>;
> +
> + ams_ps: ams-ps@0,0 {
> + compatible = "xlnx,zynqmp-ams-ps";
> + reg = <0 0x400>;
> + };
> +
> + ams_pl: ams-pl@1,0 {
> + compatible = "xlnx,zynqmp-ams-pl";
> + reg = <0x400 0x400>;
> + xlnx,ext-channels {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + channel@30 {
> + reg = <30>;
> + xlnx,bipolar;
> + };
> + channel@31 {
> + reg = <31>;
> + };
> + channel@38 {
> + reg = <38>;
> + xlnx,bipolar;
> + };
> + };
> + };
> + };
> + };
> --
> 2.17.1