Re: [PATCH v4 1/3] dt-bindings: PCI: intel: Add YAML schemas for the PCIe RC controller

From: Rob Herring
Date: Fri Oct 25 2019 - 12:53:57 EST


On Mon, Oct 21, 2019 at 02:39:18PM +0800, Dilip Kota wrote:
> Add YAML shcemas for PCIe RC controller on Intel Gateway SoCs
> which is Synopsys DesignWare based PCIe core.
>
> changes on v4:
> Add "snps,dw-pcie" compatible.
> Rename phy-names property value to pcie.
> And maximum and minimum values to num-lanes.
> Add ref for reset-assert-ms entry and update the
> description for easy understanding.
> Remove pcie core interrupt entry.
>
> changes on v3:
> Add the appropriate License-Identifier
> Rename intel,rst-interval to 'reset-assert-us'
> Add additionalProperties: false
> Rename phy-names to 'pciephy'
> Remove the dtsi node split of SoC and board in the example
> Add #interrupt-cells = <1>; or else interrupt parsing will fail
> Name yaml file with compatible name
>
> Signed-off-by: Dilip Kota <eswara.kota@xxxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/pci/intel-gw-pcie.yaml | 135 +++++++++++++++++++++
> 1 file changed, 135 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml

Fails to validate:

Error: Documentation/devicetree/bindings/pci/intel-gw-pcie.example.dts:38.27-28 syntax error
FATAL ERROR: Unable to parse input tree
scripts/Makefile.lib:321: recipe for target 'Documentation/devicetree/bindings/pci/intel-gw-pcie.example.dt.yaml' failed

Please run 'make -k dt_binding_check' (-k because there are some
unrelated failures).

>
> diff --git a/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml b/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml
> new file mode 100644
> index 000000000000..49dd87ec1e3d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/intel-gw-pcie.yaml
> @@ -0,0 +1,135 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/intel-gw-pcie.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: PCIe RC controller on Intel Gateway SoCs
> +
> +maintainers:
> + - Dilip Kota <eswara.kota@xxxxxxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + items:
> + - const: intel,lgm-pcie
> + - const: snps,dw-pcie
> +
> + device_type:
> + const: pci
> +
> + "#address-cells":
> + const: 3
> +
> + "#size-cells":
> + const: 2
> +
> + reg:
> + items:
> + - description: Controller control and status registers.
> + - description: PCIe configuration registers.
> + - description: Controller application registers.
> +
> + reg-names:
> + items:
> + - const: dbi
> + - const: config
> + - const: app
> +
> + ranges:
> + description: Ranges for the PCI memory and I/O regions.

How many entries do you expect? Add a 'maxItems' to define.

> +
> + resets:
> + maxItems: 1
> +
> + clocks:
> + description: PCIe registers interface clock.

How many clocks?

> +
> + phys:
> + maxItems: 1
> +
> + phy-names:
> + const: pcie
> +
> + reset-gpios:
> + maxItems: 1
> +
> + num-lanes:
> + minimum: 1
> + maximum: 2
> + description: Number of lanes to use for this port.
> +
> + linux,pci-domain:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: PCI domain ID.

Just a value of 'true' is fine here.

> +
> + '#interrupt-cells':
> + const: 1
> +
> + interrupt-map-mask:
> + description: Standard PCI IRQ mapping properties.
> +
> + interrupt-map:
> + description: Standard PCI IRQ mapping properties.
> +
> + max-link-speed:
> + description: Specify PCI Gen for link capability.

Allowed values? Default?

> +
> + bus-range:
> + description: Range of bus numbers associated with this controller.
> +
> + reset-assert-ms:
> + $ref: /schemas/types.yaml#/definitions/uint32

Don't need a type for standard units.

> + description: |
> + Delay after asserting reset to the PCIe device.
> + Some devices need an interval upto 500ms. By default it is 100ms.

Express as a schema:

maximum: 500
default: 100

> +
> +required:
> + - compatible
> + - device_type
> + - reg
> + - reg-names
> + - ranges
> + - resets
> + - clocks
> + - phys
> + - phy-names
> + - reset-gpios
> + - num-lanes

Shouldn't be required. It should have a default.

> + - linux,pci-domain

Is this really required? AIUI, domains are optional and only used if
you have more than one host.

> + - interrupt-map
> + - interrupt-map-mask
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + pcie10:pcie@d0e00000 {

space ^

> + compatible = "intel,lgm-pcie", "snps,dw-pcie";
> + device_type = "pci";
> + #address-cells = <3>;
> + #size-cells = <2>;
> + reg = <0xd0e00000 0x1000>,
> + <0xd2000000 0x800000>,
> + <0xd0a41000 0x1000>;
> + reg-names = "dbi", "config", "app";
> + linux,pci-domain = <0>;
> + max-link-speed = <4>;
> + bus-range = <0x00 0x08>;
> + interrupt-parent = <&ioapic1>;
> + #interrupt-cells = <1>;
> + interrupt-map-mask = <0 0 0 0x7>;
> + interrupt-map = <0 0 0 1 &ioapic1 27 1>,
> + <0 0 0 2 &ioapic1 28 1>,
> + <0 0 0 3 &ioapic1 29 1>,
> + <0 0 0 4 &ioapic1 30 1>;
> + ranges = <0x02000000 0 0xd4000000 0xd4000000 0 0x04000000>;
> + resets = <&rcu0 0x50 0>;
> + clocks = <&cgu0 LGM_GCLK_PCIE10>;

You need to include any defines you use. That's why the example fails to
build.

> + phys = <&cb0phy0>;
> + phy-names = "pcie";
> + status = "okay";

Don't show status in examples.

> + reset-assert-ms = <500>;
> + reset-gpios = <&gpio0 3 GPIO_ACTIVE_LOW>;
> + num-lanes = <2>;
> + };
> --
> 2.11.0
>