Automated PR - 2026-07-07

packages/ltx-kernels/src/ltx_kernels/arch.py

@@ -0,0 +1,21 @@
+"""GPU architecture detection for blockwise kernel dispatch."""
+
+import torch
+
+
+def get_device_arch() -> str:
+    """Return a coarse architecture name for the current CUDA device.
+    Used to pick the FP8 GEMM kernel variant (SM89 vs SM90) at runtime.
+    """
+    if not torch.cuda.is_available():
+        raise RuntimeError("CUDA is not available; blockwise kernels require a CUDA device.")
+    major, minor = torch.cuda.get_device_capability(torch.cuda.current_device())
+    if major == 8 and (minor >= 0 and minor < 9):
+        return "ampere"
+    if major == 8 and minor == 9:
+        return "ada"
+    if major == 9 and minor == 0:
+        return "hopper"
+    if major in {10, 12}:
+        return "blackwell"
+    raise NotImplementedError(f"Unsupported GPU compute capability sm_{major}{minor}.")