Re: [PATCH v4 01/10] dt-bindings: PCI: Add binding for Toshiba TC956x PCIe switch

Krzysztof Kozlowski
2025-02-26T07:30:20Z

On Tue, Feb 25, 2025 at 03:03:58PM +0530, Krishna Chaitanya Chundru wrote:
> From: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>
> Add a device tree binding for the Toshiba TC956x PCIe switch, which
> provides an Ethernet MAC integrated to the 3rd downstream port and two
> downstream PCIe ports.
>
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Drop, file was named entirely different. I see other changes, altough
comparing with b4 is impossible.

Why b4 does not work for this patch?

b4 diff '20250225-qps615_v4_1-v4-1-e08633a7bdf8@oss.qualcomm.com'
Checking for older revisions
Grabbing search results from lore.kernel.org
Nothing matching that query.

Looks like you use b4 but decide to not use b4 changesets/versions. Why
making it difficult for reviewers and for yourself?

> ---
> .../devicetree/bindings/pci/toshiba,tc956x.yaml | 178 +++++++++++++++++++++
> 1 file changed, 178 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pci/toshiba,tc956x.yaml b/Documentation/devicetree/bindings/pci/toshiba,tc956x.yaml
> new file mode 100644
> index 000000000000..ffed23004f0d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/toshiba,tc956x.yaml

What is "x" here? Wildcard?

> @@ -0,0 +1,178 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/toshiba,tc956x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Toshiba TC956x PCIe switch
> +
> +maintainers:
> + - Krishna chaitanya chundru <quic_krichai@quicinc.com>
> +
> +description: |
> + Toshiba TC956x PCIe switch has one upstream and three downstream

TC9560? Which one are you using here?

> + ports. The 3rd downstream port has integrated endpoint device of
> + Ethernet MAC. Other two downstream ports are supposed to connect
> + to external device.
> +
> + The TC956x PCIe switch can be configured through I2C interface before
> + PCIe link is established to change FTS, ASPM related entry delays,
> + tx amplitude etc for better power efficiency and functionality.
> +
> +properties:
> + compatible:
> + items:
> + - enum:
> + - "pci1179,0623"

Why quotes?

> + - const: pciclass,0604
> +
> + reg:
> + maxItems: 1
> +
> + i2c-parent:
> + $ref: /schemas/types.yaml#/definitions/phandle-array
> + description:
> + A phandle to the parent I2C node and the slave address of the device
> + used to do configure tc956x to change FTS, tx amplitude etc.
> + items:
> + - description: Phandle to the I2C controller node
> + - description: I2C slave address
> +
> + vdd18-supply: true
> +
> + vdd09-supply: true
> +
> + vddc-supply: true
> +
> + vddio1-supply: true
> +
> + vddio2-supply: true
> +
> + vddio18-supply: true
> +
> + reset-gpios:
> + maxItems: 1
> + description:
> + GPIO controlling the RESX# pin.
> +
> +allOf:
> + - $ref: "#/$defs/tc956x-node"
> +
> +patternProperties:
> + "^pcie@[1-3],0$":
> + description:
> + child nodes describing the internal downstream ports
> + the tc956x switch.
> + type: object
> + $ref: "#/$defs/tc956x-node"
> + unevaluatedProperties: false
> +
> +$defs:
> + tc956x-node:
> + type: object
> +
> + properties:
> + tc956x,tx-amplitude-microvolt:

You already got comments on this.

> + $ref: /schemas/types.yaml#/definitions/uint32

Never tested.

> + description:
> + Change Tx Margin setting for low power consumption.
> +
> + tc956x,no-dfe-support:

There is no such vendor prefix and you already got exactly the same
comment at v3. How did you resolve that comment?

> + type: boolean
> + description:
> + Disable DFE (Decision Feedback Equalizer), which mitigates
> + intersymbol interference and some reflections caused by impedance mismatches.
> +
> + allOf:
> + - $ref: /schemas/pci/pci-pci-bridge.yaml#
> +
> +unevaluatedProperties: false

Keep order as in example-schema.

Best regards,
Krzysztof