RawTotalLighting

[glorybound]

I use it in Photoshop to place over the grass I paste in, but now I don't have that option. Is there another way in GPU?

[M.Max]

If you could use compositing software it would be easier for such cases, but for Photoshop here how it could be done :
Add your GI to Lighting then divide with Diffuse filter ..make sure that you are working in 32 bit to get correct math .then convert these 3 layers to one smart object and use it as your raw total light pass . there would be some issues with alpha because of the known premultiplied alpha limitations in Photoshop, but for the grass I think that wont be an issue .
check the image below :

[glorybound]

I'll give it a try. I am not sure why it has to be so complicated now. Thank you!