[Core] Scope PCP-DP validation to GPU manager

vllm/config/parallel.py

@@ -547,8 +547,6 @@ def _validate_parallel_config(self) -> Self:
         tp = self.tensor_parallel_size
         pcp = self.prefill_context_parallel_size
         dcp = self.decode_context_parallel_size
-        if pcp > 1 and self.data_parallel_size > 1:
-            raise ValueError("PCP does not support data parallelism yet.")
         if pcp == 1:
             # DCP reuses the TP ranks when PCP is disabled.
             if tp % dcp != 0:

vllm/platforms/cuda.py

@@ -322,6 +322,12 @@ def check_and_update_config(cls, vllm_config: VllmConfig) -> None:
         parallel_config = vllm_config.parallel_config
         model_config = vllm_config.model_config
 
+        if (
+            parallel_config.prefill_context_parallel_size > 1
+            and parallel_config.data_parallel_size > 1
+        ):
+            raise ValueError("PCP does not support data parallelism on CUDA yet.")
+
         if parallel_config.worker_cls == "auto":
             parallel_config.worker_cls = "vllm.v1.worker.gpu_worker.Worker"
 

vllm/platforms/rocm.py

@@ -900,6 +900,12 @@ def check_and_update_config(cls, vllm_config: "VllmConfig") -> None:
         compilation_config = vllm_config.compilation_config
         parallel_config = vllm_config.parallel_config
 
+        if (
+            parallel_config.prefill_context_parallel_size > 1
+            and parallel_config.data_parallel_size > 1
+        ):
+            raise ValueError("PCP does not support data parallelism on ROCm yet.")
+
         if (
             compilation_config.cudagraph_mode.has_full_cudagraphs()
             and parallel_config.prefill_context_parallel_size > 1