[ROCm] Enable DeepSeek-V4 on gfx11 (#47017)

This PR enables DeepSeek-V4 checkpoints on ROCm gfx11/RDNA devices.

Signed-off-by: Letian Kang <Letian.Kang@amd.com>

vllm/_aiter_ops.py

@@ -2025,12 +2025,27 @@ class rocm_aiter_ops:
 
     @staticmethod
     def register_ops_once() -> None:
+        global _OPS_REGISTERED
+
         if not (
             is_aiter_found_and_supported() or is_aiter_found_and_supported_on_rdna4()
         ):
+            if not current_platform.is_rocm():
+                return
+
+            from vllm.platforms.rocm import on_gfx11
+
+            if on_gfx11() and not _OPS_REGISTERED:
+                direct_register_custom_op(
+                    op_name="rocm_aiter_sparse_attn_indexer",
+                    op_func=rocm_aiter_sparse_attn_indexer,
+                    mutates_args=["topk_indices_buffer"],
+                    fake_impl=rocm_aiter_sparse_attn_indexer_fake,
+                    dispatch_key=current_platform.dispatch_key,
+                )
+                _OPS_REGISTERED = True
             return
 
-        global _OPS_REGISTERED
         if not _OPS_REGISTERED:
             # register all the custom ops here
             direct_register_custom_op(

vllm/model_executor/layers/sparse_attn_indexer.py

@@ -850,7 +850,13 @@ class SparseAttnIndexer(CustomOp):
         assert isinstance(q_quant, torch.Tensor), (
             "AMD sparse_attn_indexer expects a single FP8 q_quant tensor"
         )
-        if rocm_aiter_ops.is_enabled() or rocm_aiter_ops.is_rdna_aiter_enabled():
+        from vllm.platforms.rocm import on_gfx11
+
+        if (
+            rocm_aiter_ops.is_enabled()
+            or rocm_aiter_ops.is_rdna_aiter_enabled()
+            or on_gfx11()
+        ):
             return torch.ops.vllm.rocm_aiter_sparse_attn_indexer(
                 hidden_states,
                 _encode_layer_name(self.k_cache.prefix),

vllm/platforms/rocm.py

@@ -520,6 +520,7 @@ class RocmPlatform(Platform):
         "deepseek_v4_fp8",
         "compressed-tensors",
         "fbgemm_fp8",
+        "inc",
         "quark",
         "mxfp4",
         "mxfp8",