According to the i.MX8M reference manual, the GC7000lite at 800Mhz is capable of 1.6 Giga pixel/sec fill rate. We need to better understand this number. My assumption is that this means the GPU can do 2 pixels/clock cycle due to there being 2 texture units and 2 pixel units in the GPU just like with the i.MX6q(p).
Typically, the GPU will have different pixel fill rates depending on the type of operation being performed. For example, with some GPUs, you get the highest fill rate ONLY when filling with a solid color and not from a texture. Then you get some lower fill rate when filling with texture data sampled from an RGB buffer, and lastly you get an even lower fill rate when filling pixels that are sampled from various YUV texture buffers. We are looking for documentation that explains what the fill rate is for each type of pixel being filled. Preferably, some charts like the charts that are available in the i.MX6q reference manual that describe the number of pixels/clock for each of the different operations the 2D GPU supports. Below is an example of what we are looking for with the GC7000lite GPU: (This example data is from the Vivante GC320 in the i.MX6q.)