At one point, Sony was asking developers whether they would be interested in having PSGL conform to the OpenGL ES 2.0 specs (link here). This has unfortunately never happened however, as developers seem to have mostly preferred to go with libGCM as their main graphics API of choice on PS3. This has meant that the development environment has started becoming more libGCM-centric over the years with PSGL eventually becoming a second-class citizen – in fact, new features like 3D stereo mode is not even possible unless you are using libGCM directly.
</quote>
I assume as former PS3 dev you also have access to the GLESTutorial07_Arnaud_Remi_PSGL.pdf done at GDC 2006, otherwise you can get it from https://tinyurl.com/yajn75h2.
As for a source, here is one from Sandstorm developers.
https://sandstormgames.ca/2011/07/22/debug-playstation3/
<quote>
At one point, Sony was asking developers whether they would be interested in having PSGL conform to the OpenGL ES 2.0 specs (link here). This has unfortunately never happened however, as developers seem to have mostly preferred to go with libGCM as their main graphics API of choice on PS3. This has meant that the development environment has started becoming more libGCM-centric over the years with PSGL eventually becoming a second-class citizen – in fact, new features like 3D stereo mode is not even possible unless you are using libGCM directly.
</quote>
I assume as former PS3 dev you also have access to the GLESTutorial07_Arnaud_Remi_PSGL.pdf done at GDC 2006, otherwise you can get it from https://tinyurl.com/yajn75h2.