diff options
Diffstat (limited to 'src/mainboard')
| -rw-r--r-- | src/mainboard/google/gru/mainboard.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/mainboard/google/gru/mainboard.c b/src/mainboard/google/gru/mainboard.c index 8a6cda203d..a2b74badf2 100644 --- a/src/mainboard/google/gru/mainboard.c +++ b/src/mainboard/google/gru/mainboard.c @@ -158,6 +158,15 @@ static void configure_display(void) static void setup_usb(void) { + /* A few magic PHY tuning values that improve eye diagram amplitude + * and make it extra sure we get reliable communication in firmware. */ + /* Set max ODT compensation voltage and current tuning reference. */ + write32(&rk3399_grf->usbphy0_ctrl[3], 0x0fff02e3); + write32(&rk3399_grf->usbphy1_ctrl[3], 0x0fff02e3); + /* Set max pre-emphasis level, only on Kevin PHY0. */ + if (IS_ENABLED(CONFIG_BOARD_GOOGLE_KEVIN)) + write32(&rk3399_grf->usbphy0_ctrl[12], 0xffff00a7); + setup_usb_otg0(); setup_usb_otg1(); } |