On 18-10-19, 17:03, andrew-sh.cheng wrote: > On Thu, 2019-10-17 at 12:01 +0530, Viresh Kumar wrote: > > On 16-10-19, 10:43, andrew-sh.cheng wrote: > > > This is due to SVS feature need to fix Vproc for calibration. > > > When SVS calibration, it want to disable all opp items, except one with > > > voltae 1.0V. (SVS will change the voltage field of that opp item, if the > > > corresponding voltage is not 1.0V) > > > In this way, SVS can make sure there is no other module, include > > > thermal, will change Vproc by DVFS driver. > > > After SVS calibration done, SVS will enable those disabled opp items > > > back. > > > > But why is this required to be done this way ? Why can't we just update the > > voltages without doing this disable/enable dance ? > > > This is because some opp items need voltage larger than 1.0V. > We cannot update the voltage to 1.0V. > > If we don't disable these opp items, and DVFS policy want to set these > high frequencies, dvfs driver will set higher voltage to Vproc and SVS > calibration will be fail. Okay. -- viresh
