It's out of my control:
 The OMAP4 processor has an internal ROM which is in charge of the USB port for booting.
Once the user application is running the USB communications are not closed and can be reused by the user application through the ROM public API.
The OMAP4 ROM is implemented in a way it requires interrupts enabled.

Regards,
  Vicente.

On Sun, Sep 30, 2012 at 5:29 PM, Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> wrote:
On 17:02 Sun 30 Sep     , vj wrote:
>    In fact the interrupts get enabled at omap4_usbboot_open, it's required
>    for usb transfers.
>    For this reason the interrupts are disabled at barebox exit.
why do you enable the interrupts?

we never use interrupts in barebox

Best Regards,
J.