On 4/29/20 5:50 PM, Rafael J. Wysocki wrote: > On Friday, April 24, 2020 1:40:55 PM CEST Benjamin Gaignard wrote: >> When start streaming from the sensor the CPU load could remain very low >> because almost all the capture pipeline is done in hardware (i.e. without >> using the CPU) and let believe to cpufreq governor that it could use lower >> frequencies. If the governor decides to use a too low frequency that >> becomes a problem when we need to acknowledge the interrupt during the >> blanking time. >> The delay to ack the interrupt and perform all the other actions before >> the next frame is very short and doesn't allow to the cpufreq governor to >> provide the required burst of power. That led to drop the half of the frames. >> >> To avoid this problem, DCMI driver informs the cpufreq governors by adding >> a cpufreq minimum load QoS resquest. > This seems to be addressing a use case that can be addressed with the help of > utilization clamps with less power overhead. Do mean clamping the policy frequencies ? I may have miss the API to do that... > > Thanks! > > >
