Full ISA documentation of the PowerVR 6 Series released to the public

[Letalis Sonus]

Imagination just published a full set of hardware documentation for their current PowerVR Rogue GPUs as a part of their PowerVR SDK: http://blog.imgtec.com/powervr/the-latest-powervr-sdk-v3-4-and-tools-are-live

Hopefully more will follow so we'll get a proper free driver for the Pandora and Pyra in the near future, that would probably even introduce new features like full OpenGL support.

 

[lunixbochs]

The Pyra uses a 5-series PowerVR chip, but there's probably some overlap or at least information to be learned from proper ISA docs of a similar GPU.

 

[Letalis Sonus]

According to Luc Verhaegen it seems that someone got things wrong while writing about it:

What was released was the assembly language for the PowerVR shaders, which then needs to be assembled by the IMG RGX assembler to provide the actual shader binaries. This is definitely not the ISA, and I do not know whether it was Alexandru Voica (an Imagination marketing guy who suddenly became active on the phoronix forums, and who i believe to be the originator of this story) or the author of the article on Phoronix who made this error. I do not think that this was bad intent though, just that something got lost in translation.

The release of the assembly language is very nice though. It makes it relatively straightforward to match the assembly to the machine code, and takes away most of the pain of ISA REing.

Despite the botched message, this was a big step forwards for ARM GPU makers; Imagination delivered what its customers need (in this case, the ability to manually tune some shaders), and in the process it also made it easier for potential REers to create an open source driver.