[PATCH 1/2] serial: amba-pl011: use cpu_relax when polling registers

[Peter Hurley]

On 11/03/2015 10:01 AM, Timur Tabi wrote:
> Busy loops that poll on a register should call cpu_relax().  On some
> architectures, it can lower CPU power consumption or yield to a
> hyperthreaded twin processor.  It also serves as a compiler barrier,
> so it can replace barrier() calls.

Reviewed-by: Peter Hurley <peter at hurleysoftware.com>