Hi Sakari, Em Mon, 8 May 2017 18:03:12 +0300 Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> escreveu: > Hello, > > This is a rebased and partially reworked version of the vb2 cache hints > support patch series posted by first myself, then Laurent and then myself > again. > > I'm still posting this as RFC primarily because more testing and driver > changes will be needed. In particular, a lot of platform drivers assume > non-coherent memory but are not properly labelled as such. The main issue I see is that, if the driver doesn't "annotate" if it is requiring coherent or non-coherent memory, VB2 should be preserving its old behavior, as, otherwise, it will risk causing regressions. So, perhaps instead of creating a single flag V4L2_BUF_FLAG_NO_CACHE_SYNC, it would make sense to create two flags, using either one of them on newer drivers. For old drivers that won't set either, it would keep the current behavior. Thanks, Mauro
