Re: [PATCH v2 2/8] dt-bindings: PCI: renesas-pci-usb: Convert bindings to json-schema

[Herve Codina <herve.codina@bootlin.com>]

Hi Rob,

On Thu, 14 Apr 2022 13:15:30 -0500
Rob Herring <robh@kernel.org> wrote:

> On Thu, Apr 14, 2022 at 09:40:05AM +0200, Herve Codina wrote:
> > Convert Renesas PCI bridge bindings documentation to json-schema.
> > Also name it 'renesas,pci-usb' as it is specifically used to
> > connect the PCI USB controllers to AHB bus.  
> 
> Please name it based on compatible strings. renesas,pci-rcar-gen2.yaml

Ok, renamed.

> 
> > 
> > Signed-off-by: Herve Codina <herve.codina@bootlin.com>
> > ---
> >  .../devicetree/bindings/pci/pci-rcar-gen2.txt |  84 -----------
> >  .../bindings/pci/renesas,pci-usb.yaml         | 134 ++++++++++++++++++
> >  2 files changed, 134 insertions(+), 84 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/pci/pci-rcar-gen2.txt
> >  create mode 100644 Documentation/devicetree/bindings/pci/renesas,pci-usb.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/pci/pci-rcar-gen2.txt b/Documentation/devicetree/bindings/pci/pci-rcar-gen2.txt
> > deleted file mode 100644
...
> > diff --git a/Documentation/devicetree/bindings/pci/renesas,pci-usb.yaml b/Documentation/devicetree/bindings/pci/renesas,pci-usb.yaml
> > new file mode 100644
...
> > index 000000000000..3f8d79b746c7
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/pci/renesas,pci-usb.yaml
> > @@ -0,0 +1,134 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/pci/renesas,pci-usb.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Renesas AHB to PCI bridge
> > +
> > +maintainers:
> > +  - Marek Vasut <marek.vasut+renesas@gmail.com>
> > +  - Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > +
> > +description: |
> > +  This is the bridge used internally to connect the USB controllers to the
> > +  AHB. There is one bridge instance per USB port connected to the internal
> > +  OHCI and EHCI controllers.
> > +
> > +allOf:
> > +  - $ref: /schemas/pci/pci-bus.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    oneOf:
> > +      - items:
> > +          - enum:
> > +              - renesas,pci-r8a7742      # RZ/G1H
> > +              - renesas,pci-r8a7743      # RZ/G1M
> > +              - renesas,pci-r8a7744      # RZ/G1N
> > +              - renesas,pci-r8a7745      # RZ/G1E
> > +              - renesas,pci-r8a7790      # R-Car H2
> > +              - renesas,pci-r8a7791      # R-Car M2-W
> > +              - renesas,pci-r8a7793      # R-Car M2-N
> > +              - renesas,pci-r8a7794      # R-Car E2
> > +          - const: renesas,pci-rcar-gen2 # R-Car Gen2 and RZ/G1
> > +
> > +  reg:
> > +    description: |
> > +      A list of physical regions to access the device. The first is
> > +      the operational registers for the OHCI/EHCI controllers and the
> > +      second is for the bridge configuration and control registers.
> > +    minItems: 2
> > +    maxItems: 2
> > +
> > +  interrupts:
> > +    description: Interrupt for the device.
> > +
> > +  interrupt-map:
> > +    description: |
> > +      Standard property used to define the mapping of the PCI interrupts
> > +      to the GIC interrupts.
> > +
> > +  interrupt-map-mask:
> > +    description:
> > +      Standard property that helps to define the interrupt mapping.
> > +
> > +  clocks:
> > +    description: The reference to the device clock.
> > +
> > +  bus-range:
> > +    description: |
> > +      The PCI bus number range; as this is a single bus, the range
> > +      should be specified as the same value twice.  
> 
> items:
>   const: 0

Well, some other values are present in some dtsi files such as
'bus_range = <1 1>;' or 'bus_range = <2 2>;' in r8a7742.dtsi.

The constraint is to have the same value twice. Is there a way
to specify this constraint ?

> 
> > +
> > +  "#address-cells":
> > +    const: 3
> > +
> > +  "#size-cells":
> > +    const: 2
> > +
> > +  "#interrupt-cells":
> > +    const: 1  
> 
> All these are defined by pci-bus.yaml

Right.
Replaced by:

"#address-cells": true
"#size-cells": true
"#interrupt-cells": true

Is that correct ?

> 
> > +
> > +  dma-ranges:
> > +    description: |
> > +      A single range for the inbound memory region. If not supplied,
> > +      defaults to 1GiB at 0x40000000. Note there are hardware restrictions on
> > +      the allowed combinations of address and size.  
> 
> 'a single range' == 'maxItems: 1'

Ok, maxItems added.

> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +  - interrupt-map
> > +  - interrupt-map-mask
> > +  - clocks
> > +  - bus-range
> > +  - "#address-cells"
> > +  - "#size-cells"
> > +  - "#interrupt-cells"
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +    #include <dt-bindings/clock/r8a7790-cpg-mssr.h>
> > +
> > +    bus {
> > +        #address-cells = <2>;
> > +        #size-cells = <2>;
> > +
> > +        pci0: pci@ee090000  {
> > +            compatible = "renesas,pci-r8a7790", "renesas,pci-rcar-gen2";
> > +            device_type = "pci";
> > +            clocks = <&cpg CPG_MOD 703>;
> > +            reg = <0 0xee090000 0 0xc00>,
> > +                  <0 0xee080000 0 0x1100>;
> > +            interrupts = <GIC_SPI 108 IRQ_TYPE_LEVEL_HIGH>;
> > +            status = "disabled";  
> 
> Don't disable your example.

Ok, done


Thanks for the review.
Hervé

-- 
Hervé Codina, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com