[V1 Loader] Support qwen2(bf16) (#3502)

* support qwen2(bf16)

* merge bias_loader and weight_loader

fastdeploy/model_executor/models/qwen2.py

@@ -305,6 +305,47 @@ class Qwen2ForCausalLM(ModelForCasualLM):
             prefix="lm_head",
         )
 
+    @paddle.no_grad()
+    def load_weights(self, weights_iterator) -> None:
+        """
+        Load model parameters from a given weights_iterator object.
+
+        Args:
+            weights_iterator (Iterator): An iterator yielding (name, weight) pairs.
+        """
+
+        from fastdeploy.model_executor.models.utils import default_weight_loader
+
+        stacked_params_mapping = [
+            # (param_name, shard_name, shard_id)
+            ("qkv_proj", "q_proj", "q"),
+            ("qkv_proj", "k_proj", "k"),
+            ("qkv_proj", "v_proj", "v"),
+            ("up_gate_proj", "gate_proj", "gate"),
+            ("up_gate_proj", "up_proj", "up"),
+            ("embed_tokens.embeddings", "embed_tokens", None),
+            ("lm_head.linear", "lm_head", None),
+        ]
+
+        params_dict = dict(self.named_parameters())
+        for loaded_weight_name, loaded_weight in weights_iterator:
+            for param_name, weight_name, shard_id in stacked_params_mapping:
+                if weight_name not in loaded_weight_name:
+                    continue
+                model_param_name = loaded_weight_name.replace(weight_name, param_name)
+                if model_param_name not in params_dict:
+                    continue
+                param = params_dict[model_param_name]
+                weight_loader = getattr(param, "weight_loader", default_weight_loader(self.fd_config))
+                weight_loader(param, loaded_weight, shard_id)
+                break
+            else:
+                if loaded_weight_name not in params_dict:
+                    continue
+                param = params_dict[loaded_weight_name]
+                weight_loader = getattr(param, "weight_loader", default_weight_loader(self.fd_config))
+                weight_loader(param, loaded_weight)
+
     @classmethod
     def name(self):
         """ """