On 16 June 2017 at 07:31, Bin Meng <bmeng...@gmail.com> wrote: > Occasionally it was observed that on Intel MinnowMax board, with a > USB 2.0 device connected to the bottom port, when doing 'usb start' > on the xHCI controller: > > scanning bus 0 for devices... cannot reset port 3!? > > But neither of the two USB ports is routed to xHCI root port 3. > Adding some debug information shows that xHCI port 3 PORTSC register > mysteriously reports both CCS = 1 and CSC = 1. > > This is not seen every time. After increasing the timeout to wait > for power to become stable, the issue is gone. So this indicates > current default USB power-on delay (20ms) might be at a critical > region where power is stable/unstable. U-Boot provides a mechanism > to have a environment variable to override the default one. Add > one for MinnowMax. > > Signed-off-by: Bin Meng <bmeng...@gmail.com> > --- > > include/configs/minnowmax.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-)
Reviewed-by: Simon Glass <s...@chromium.org> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
