Hi Andy, On Thu, Mar 17, 2022 at 03:23:12PM +0800, Andy Yan wrote: > I found a obvious error in 0x604(OVERLAY_LAYER_SEL) register, the > configuration value > > is 0x54763513. > > I am not sure if you know clearly about this register: > > Every four bits of this register select a Window(Cluster0,Cluster1, > Esmart0, Esmart1, Smart0. Smart1) > > for layer0 to layer 5 from bottom to top. > > 0: Cluster0 > > 1: Cluster1: > > 2: Esmart0 > > 3: Smart0 > > 6: Esmart1 > > 7: Smart1 > > And one window can only be selected by one layer at a time. > > So when I change this register to 0x54762513, the square draw by > weston-simple-dmabuf-egl appeared on the top of the weston background on > screen. I can reproduce this here. It seems I have only tested overlays with two active VPs. With only one active VP I see the same behaviour as you do. The following patch fixes this, will include that in the next round. Sascha ------------------------------8<-------------------------------