AMD_DEBUG Can Now Be Used In Place Of R600_DEBUG For RadeonSI Options

When setting various debug options for the RadeonSI Gallium3D driver -- like enabling its NIR back-end among many other options -- that has traditionally been done through the R600_DEBUG= environment variable. But that variable name makes little sense these days since RadeonSI doesn't even support the now-vintage R600 GPUs. Thankfully, AMD_DEBUG= is now a supported alternative.

Marek Olšák added the support on Tuesday so the AMD_DEBUG environment variable for RadeonSI can now be used as an alternative to R600_DEBUG -- using that environment variable is still supported to keep any scripts, etc, working.

RadeonSI's use of R600_DEBUG is a vintage remnant stemming from the days of the R600 Gallium3D driver and carried over into the RadeonSI driver when it was introduced for providing AMD GCN graphics support. By now most long-time enthusiasts/gamers are used to writing R600_DEBUG even in the context of RadeonSI, but at least having AMD_DEBUG instead is long overdue and will hopefully avoid confusion by new users. So this article is just to serve as a quick alert about this new/alternative option in Mesa 19.1.