Hi Xiaoliang, On Mon, Apr 19, 2021 at 06:25:30PM +0800, Xiaoliang Yang wrote: > ALWAYS_GUARD_BAND_SCH_Q bit in TAS config register is descripted as > this: > 0: Guard band is implemented for nonschedule queues to schedule > queues transition. > 1: Guard band is implemented for any queue to schedule queue > transition. > > The driver set guard band be implemented for any queue to schedule queue > transition before, which will make each GCL time slot reserve a guard > band time that can pass the max SDU frame. Because guard band time could > not be set in tc-taprio now, it will use about 12000ns to pass 1500B max > SDU. This limits each GCL time interval to be more than 12000ns. > > This patch change the guard band to be only implemented for nonschedule > queues to schedule queues transition, so that there is no need to reserve > guard band on each GCL. Users can manually add guard band time for each > schedule queues in their configuration if they want. > > Signed-off-by: Xiaoliang Yang <xiaoliang.yan...@nxp.com> > ---
What is a scheduled queue? When time-aware scheduling is enabled on the port, why are some queues scheduled and some not?