AMD GFX1150 & GFX1151 Targets Being Added To AMDGPU LLVM Backend

[phoronix]

Phoronix: AMD GFX1150 & GFX1151 Targets Being Added To AMDGPU LLVM Backend

New AMDGPU targets seeing the initial plumbing merged today for LLVM 17 are GFX1150 and GFX1151 as upcoming AMD APU products...

https://www.phoronix.com/news/LLVM-AMD-GFX1150-GFX1151

[Terr-E]

I find it confusing that although it's listed under RDNA 3, the architecture is still referred to as "amdgcn". If I hadn't actually browsed the code I would think it referred to a Vega APU. Probably not worth the effort to refactor that. Or maybe GCN and RDNA are in the same driver package somehow ? Because the only other architecture I saw in this file e.g. was "r600"…

[mbriar]

I find it confusing that although it's listed under RDNA 3, the architecture is still referred to as "amdgcn". If I hadn't actually browsed the code I would think it referred to a Vega APU. Probably not worth the effort to refactor that. Or maybe GCN and RDNA are in the same driver package somehow ? Because the only other architecture I saw in this file e.g. was "r600"…

The RDNA ISA still still pretty much the same as GCN, with some changes of course between generations, but that's also true for GCN 1,2,3... So there is no reason for the target in LLVM to get a different name.

[agd5f]

I find it confusing that although it's listed under RDNA 3, the architecture is still referred to as "amdgcn". If I hadn't actually browsed the code I would think it referred to a Vega APU. Probably not worth the effort to refactor that. Or maybe GCN and RDNA are in the same driver package somehow ? Because the only other architecture I saw in this file e.g. was "r600"…

The shader ISA has not changed significantly since GCN (GFX6). That was a substantially different ISA from pre-GFX6 hardware (r600) and warranted a new shader backend. That is not the case with CDNA and RDNA; the same shader backend works just fine for all ISA families since GFX6.

[bridgman]

I find it confusing that although it's listed under RDNA 3, the architecture is still referred to as "amdgcn". If I hadn't actually browsed the code I would think it referred to a Vega APU. Probably not worth the effort to refactor that. Or maybe GCN and RDNA are in the same driver package somehow ? Because the only other architecture I saw in this file e.g. was "r600"…

If it helps, remember that driver component projects are named for the *first* generation of hardware they support. The rationale is that when a component is created we know the first generation that will be supported but we have no idea what the last generation to be covered will be since it probably does not exist yet.

In the same way, the "radeon" kernel driver supports the original radeon GPUs (R100) plus several later generations (right up to CI), and the "radeonsi" Mesa driver supports the original GCN part (Southern Islands / GFX6) right up to RDNA3 and beyond.