Re: [PATCH v3 08/11] devicetree: bindings: pci: document PARF params bindings

From: Rob Herring
Date: Thu May 07 2020 - 14:10:57 EST


On Fri, May 01, 2020 at 12:06:15AM +0200, Ansuel Smith wrote:
> It is now supported the editing of Tx De-Emphasis, Tx Swing and
> Rx equalization params on ipq8064. Document this new optional params.
>
> Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
> ---
> .../devicetree/bindings/pci/qcom,pcie.txt | 36 +++++++++++++++++++
> 1 file changed, 36 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.txt b/Documentation/devicetree/bindings/pci/qcom,pcie.txt
> index 6efcef040741..8cc5aea8a1da 100644
> --- a/Documentation/devicetree/bindings/pci/qcom,pcie.txt
> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.txt
> @@ -254,6 +254,42 @@
> - "perst-gpios" PCIe endpoint reset signal line
> - "wake-gpios" PCIe endpoint wake signal line
>
> +- qcom,tx-deemph-gen1:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: Gen1 De-emphasis value.
> + For ipq806x should be set to 24.

Unless these need to be tuned per board, then the compatible string for
ipq806x should imply all these settings.

> +
> +- qcom,tx-deemph-gen2-3p5db:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: Gen2 (3.5db) De-emphasis value.
> + For ipq806x should be set to 24.
> +
> +- qcom,tx-deemph-gen2-6db:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: Gen2 (6db) De-emphasis value.
> + For ipq806x should be set to 34.
> +
> +- qcom,tx-swing-full:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: TX launch amplitude swing_full value.
> + For ipq806x should be set to 120.
> +
> +- qcom,tx-swing-low:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: TX launch amplitude swing_low value.
> + For ipq806x should be set to 120.
> +
> +- qcom,rx0-eq:
> + Usage: optional (available for ipq/apq8064)
> + Value type: <u32>
> + Definition: RX0 equalization value.
> + For ipq806x should be set to 4.
> +
> * Example for ipq/apq8064
> pcie@1b500000 {
> compatible = "qcom,pcie-apq8064", "qcom,pcie-ipq8064", "snps,dw-pcie";
> --
> 2.25.1
>