RTEMS-libbsd USB interrupt issue[GSOC]

[Sichen Zhao]

Hi all,

I am porting Beagle USB from FreeBSD to RTEMS-libbsd, the file i ported is from freebsd/sys/arm/ti/am335x, the file is: AM335x_musb.c , am335x_usbss.c ,etc. 

BSP: Beaglebone Black, CPU:AM335x

The issue i meeted is : When the USB1_DRVVBUS pin pull high, the interrupt vector 0x19 occured, it stuck, and don't go the the ISR. 

The code stuck at here: https://github.com/freebsd/freebsd/blob/master/sys/dev/usb/controller/musb_otg.c#L3126

The install ISR at here: https://github.com/freebsd/freebsd/blob/master/sys/arm/ti/am335x/am335x_musb.c#L299


Best Regards
Sichen Zhao