On Tue, Feb 08, 2011 at 01:37:05PM +0000, Russell King wrote: > Note that it would be a _significant_ timing disturbance as > INTERRUPT_ENABLE_SOT_MASK corresponds to 0x8a, which will cause a > misaligned access to an IO address. That may result in the alignment > handler being invoked, which will be much longer than just a single > write: > > root@vexpress:~# cat /proc/cpu/alignment > ... > System: 217 > ... > Word: 217 > ... > > That's after a few seconds of running minicom on the ftdi_sio port. With the correct register having the correct value written (SOT_MASK into the interrupt register) that pause I reported seems gone, and it no longer causes alignment faults. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
