I’m having trouble with depth textures on Linux using PowerVR SGX 540. I use them as FBO depth attachments in my program to implement algorithms for OIT, but I noticed that on the SGX the depth values are not written properly into the texture (even glClear didn’t show a change). I built a small test program that loads a depth texture with some constant values and renders the texture onto a full-screen quad into the red-component. On SGX, the framebuffer stays completely black. I tried this in PVRFrame, where it displays correctly. It also works on Mesa GLES2 with software rasterization.