From d8279fdb6d65b381f019a2be95d926b26863b8f5 Mon Sep 17 00:00:00 2001 From: nick_xr_chen Date: Tue, 22 Sep 2020 10:56:43 +0800 Subject: [PATCH] mb/google/volteer: Improve Eldrid Port 1 USB2 Eye Diagram In order to pass DB type-C USB2 eye diagram, DB USB2 PHY register needs to be overridden. port#1 PortUsb20Enable=1 Usb2PhyPetxiset=7 Usb2PhyTxiset=7 Usb2PhyPredeemp=3 Usb2PhyPehalfbit=0 BUG=b:169105751 Signed-off-by: nick_xr_chen Change-Id: If076c644783fa2992ac062d6469f9c49e6d5ff24 Reviewed-on: https://review.coreboot.org/c/coreboot/+/45598 Tested-by: build bot (Jenkins) Reviewed-by: Tim Wawrzynczak --- .../google/volteer/variants/eldrid/overridetree.cb | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/mainboard/google/volteer/variants/eldrid/overridetree.cb b/src/mainboard/google/volteer/variants/eldrid/overridetree.cb index b04b1e7295..6e9d743f72 100644 --- a/src/mainboard/google/volteer/variants/eldrid/overridetree.cb +++ b/src/mainboard/google/volteer/variants/eldrid/overridetree.cb @@ -48,6 +48,15 @@ chip soc/intel/tigerlake }, }, }" + #These settings improve the USB2 Port1 eye diagram + register "usb2_ports[4]" = "{ + .enable = 1, + .tx_bias = 7, + .tx_emp_enable = 7, + .pre_emp_bias = 3, + .pre_emp_bit = 0, + }" + device domain 0 on device pci 04.0 off end device pci 15.0 on