[SeaBIOS] USB OHCI issues when keyboard activity occurs prior to booting from thumbdrive

[Dave Frodin]

Kevin,
I mentioned in a response to the "Re: [SeaBIOS] usb-msc.c: TEST_UNIT_READY needs USB_DIR_OUT?"
email thread that when I applied the patches related to that thread the Ubuntu booting
issue that I see in this thread actually increases the passing rate from ~0% to ~50%.
Perhaps setting the DIR bit twice will solve my problem :)

I also was wondering if you could point me to the code that you referred to when you
wrote ... "I did see what appears to be a race with USB "interrupt" pipe reading" ?

thanks in advance,
Dave

> > 
> > The failure occurs when the system boots up to the GRUB menu. If I
> > let the menu timeout it will boot the default option which is
> > Ubuntu. If I hit the <Enter> key the system will lock-up with no
> > output on the debug COM port. If at the GRUB menu and I <down
> > arrow>
> > to the memtest86 option, it will sometimes work and sometimes
> > lockup.
> 
> In the processes of looking through the OHCI code, I did see what
> appears to be a race with USB "interrupt" pipe reading.  The code is
> assuming the TD is complete when the ED acknowledges the change, but
> the spec is pretty clear that the TD can be modified after the ED is
> updated.  However, I'd be quite surprised that such a small race
> would
> lead to reproducible failures.  I also don't see how it would relate
> to EHCI thumbdrive usage.
> 
> -Kevin
>