[Neuron] [Bugfix] Fix neuron startup (#9374)

Co-authored-by: Jerzy Zagorski <jzagorsk@amazon.com>

vllm/platforms/__init__.py

@@ -58,6 +58,13 @@ try:
 except Exception:
     pass
 
+is_neuron = False
+try:
+    import transformers_neuronx  # noqa: F401
+    is_neuron = True
+except ImportError:
+    pass
+
 if is_tpu:
     # people might install pytorch built with cuda but run on tpu
     # so we need to check tpu first
@@ -75,6 +82,9 @@ elif is_xpu:
 elif is_cpu:
     from .cpu import CpuPlatform
     current_platform = CpuPlatform()
+elif is_neuron:
+    from .neuron import NeuronPlatform
+    current_platform = NeuronPlatform()
 else:
     current_platform = UnspecifiedPlatform()
 

vllm/platforms/interface.py

@@ -10,6 +10,7 @@ class PlatformEnum(enum.Enum):
     TPU = enum.auto()
     XPU = enum.auto()
     CPU = enum.auto()
+    NEURON = enum.auto()
     UNSPECIFIED = enum.auto()
 
 
@@ -48,6 +49,9 @@ class Platform:
     def is_cpu(self) -> bool:
         return self._enum == PlatformEnum.CPU
 
+    def is_neuron(self) -> bool:
+        return self._enum == PlatformEnum.NEURON
+
     def is_cuda_alike(self) -> bool:
         """Stateless version of :func:`torch.cuda.is_available`."""
         return self._enum in (PlatformEnum.CUDA, PlatformEnum.ROCM)

vllm/platforms/neuron.py

@@ -0,0 +1,9 @@
+from .interface import Platform, PlatformEnum
+
+
+class NeuronPlatform(Platform):
+    _enum = PlatformEnum.NEURON
+
+    @classmethod
+    def get_device_name(cls, device_id: int = 0) -> str:
+        return "neuron"