Martin Roth (martinroth@google.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/16265
-gerrit
commit a1f0df5d369de3099d20acba6cb3531fea58845f Author: Julius Werner jwerner@chromium.org Date: Mon Aug 15 17:58:05 2016 -0700
gru: Add USB 2.0 PHY tuning for Kevin
This patch sets some magic number in magic undocumented registers that are rumored to make USB 2.0 signal integrity better on Kevin. I don't see any difference (unfortunately it doesn't solve the problems with long cables on my board), but I guess it doesn't hurt either way.
BRANCH=None BUG=chrome-os-partner:56108,chrome-os-partner:54788 TEST=Booted Kevin with USB connected through Servo. Seems to have roughly the same failure rate as before.
Change-Id: If31fb49f1ed7218b50f24e251e54c9400db72720 Signed-off-by: Martin Roth martinroth@chromium.org Original-Commit-Id: 0c5c8f0f80ea1ebb042bcb91506a6100833e7e84 Original-Change-Id: Ifbd47bf6adb63a2ca5371c0b05c5ec27a0fe3195 Original-Signed-off-by: Julius Werner jwerner@chromium.org Original-Reviewed-on: https://chromium-review.googlesource.com/370900 Original-Reviewed-by: Guenter Roeck groeck@chromium.org Original-Reviewed-by: David Schneider dnschneid@chromium.org --- src/mainboard/google/gru/mainboard.c | 9 +++++++++ src/soc/rockchip/rk3399/include/soc/grf.h | 2 +- 2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/src/mainboard/google/gru/mainboard.c b/src/mainboard/google/gru/mainboard.c index 8a6cda2..a2b74ba 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(); } diff --git a/src/soc/rockchip/rk3399/include/soc/grf.h b/src/soc/rockchip/rk3399/include/soc/grf.h index d76b827..c1fd690 100644 --- a/src/soc/rockchip/rk3399/include/soc/grf.h +++ b/src/soc/rockchip/rk3399/include/soc/grf.h @@ -73,7 +73,7 @@ struct rk3399_grf_regs { u32 reserved11[3]; u32 usbphy0_ctrl[26]; u32 reserved12[6]; - u32 usbphy1[26]; + u32 usbphy1_ctrl[26]; u32 reserved13[0x72f]; u32 soc_con9; u32 reserved14[0x0a];