# Update USB PHY tuning parameters for compliance

Update the PHY tuning parameters in UEFI to meet platform compliance
requirements.

OEMs can update the PHY tuning parameters for the Barrington and NXP
repeaters based on customer platform compliance validation results.

## Update the PHY tuning parameters

1. Open the USB device tree file:

\edk2-non-oss-qualcomm\Silicon\Qualcomm\Glymur\GlymurSiliconPkg\Settings\DeviceTree\Core\WiredConnectivity\USB\usb.dtsi
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2. Update the high-speed and SuperSpeed PHY configuration for the target
port.

    1. Use the following example to configure the USB-C0 port:

&soc {
                usb0 {
                    port@0 {
                        hs_phy_cfg {
                            // QUSB HS PHY configuration
                        }
                        ss_phy_cfg {
                            // QUSB USB3 PHY configuration
                        }
                    }
                } // usb0
            }; // soc
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    2. Apply similar updates to the remaining USB-C ports, the multiport
controller, and the high-speed-only controller.

## Related

- [Resolve common USB configuration questions](https://docs.qualcomm.com/doc/80-A0399-8/topic/resolve-common-usb-configuration-questions.html)
- [Debug the USB interface](https://docs.qualcomm.com/doc/80-A0399-8/topic/debug-usb.html)
- [References](https://docs.qualcomm.com/doc/80-A0399-8/topic/references.html)

Last Published: Sep 17, 2026

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