From 5d7cb754d78be94f103ecc18e461ee4c1c069fa2 Mon Sep 17 00:00:00 2001 From: Krishna chaitanya chundru Date: Sat, 26 Oct 2024 05:17:04 +0530 Subject: [PATCH] schemas: pci: bridge: Document PCIe equalization presets PCIe equalization presets are predefined settings used to optimize signal integrity by compensating for signal loss and distortion in high-speed data transmission. As per PCIe spec 6.0.1 revision section 8.3.3.3 & 4.2.4 for data rates of 8.0 GT/s, 16.0 GT/s, 32.0 GT/s and 64.0 GT/s provides a way to configure lane equalization presets for each lane to enhance the PCIe link reliability. Each preset value represents a different combination of pre-shoot and de-emphasis values. For each data rate it may be required to have a different preset configuration and each lane will have different preset values. Define per data rate equalization preset property with array of 16 representing 16 lanes of the PCIe. Signed-off-by: Krishna chaitanya chundru --- dtschema/schemas/pci/pci-bus-common.yaml | 36 ++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/dtschema/schemas/pci/pci-bus-common.yaml b/dtschema/schemas/pci/pci-bus-common.yaml index dfd5c32..c9391c2 100644 --- a/dtschema/schemas/pci/pci-bus-common.yaml +++ b/dtschema/schemas/pci/pci-bus-common.yaml @@ -159,6 +159,42 @@ properties: vpcie3v3aux-supply: description: 3.3v AUX regulator phandle for the slot + gen3-eq-presets: + description: + Contains the equalization preset values for PCIe data rates 8.0 GT/s. + Each preset value is used to adjust the transmitter settings to improve + signal quality and meet the electrical requirements. + $ref: /schemas/types.yaml#/definitions/uint8-array + minItems: 1 + maxItems: 16 + + gen4-eq-presets: + description: + Contains the equalization preset values for PCIe data rates 16.0 GT/s. + Each preset value is used to adjust the transmitter settings to improve + signal quality and meet the electrical requirements. + $ref: /schemas/types.yaml#/definitions/uint8-array + minItems: 1 + maxItems: 16 + + gen5-eq-presets: + description: + Contains the equalization preset values for PCIe data rates 32.0 GT/s. + Each preset value is used to adjust the transmitter settings to improve + signal quality and meet the electrical requirements. + $ref: /schemas/types.yaml#/definitions/uint8-array + minItems: 1 + maxItems: 16 + + gen6-eq-presets: + description: + Contains the equalization preset values for PCIe data rates 64.0 GT/s. + Each preset value is used to adjust the transmitter settings to improve + signal quality and meet the electrical requirements. + $ref: /schemas/types.yaml#/definitions/uint8-array + minItems: 1 + maxItems: 16 + patternProperties: "@1?[0-9a-f](,[0-7])?$": type: object