On 7.11.2024 8:36 AM, Krishna Kurapati wrote: > Enabling U1 and U2 power-saving states can lead to stability and > performance issues, particularly for latency-sensitive or high- > throughput applications. These low-power link states are intended > to reduce power consumption by allowing the device to enter partial > low-power modes during idle periods. However, they can sometimes > result in unexpected behavior. Over the years, some of the issues > seen are as follows: > > 1. In device mode of operation, when UVC is active, enabling U1/U2 > is sometimes causing packets drops due to delay in entry/exit of > intermittent low power states. These packet drops are often reflected > as Missed Isochronous transfers as the controller was not able to > send the packet in that microframe interval and hence glitches are > seen on the final transmitted video output. > > 2. On QCS6490-Rb3Gen2 Vision kit, ADB connection is heavily unstable > when U1/U2 is enabled. Often when link enters U2, there is a re- > enumeration seen and device is unusable for many use cases. Would be nice to enable it on there too, then ;) Generally per-file commits are preferred to make potential reverts easier down the road Konrad
