Support loading bf16 weights and converting them to fp32

lightx2v/common/ops/mm/mm_weight.py

@@ -37,6 +37,10 @@ try:
 except ImportError:
     gguf = None
 
+try:
+    import marlin_cuda_quant
+except ModuleNotFoundError:
+    marlin_cuda_quant = None
 
 class MMWeightTemplate(metaclass=ABCMeta):
     def __init__(self, weight_name, bias_name, lazy_load=False, lazy_load_file=None):
@@ -683,6 +687,36 @@ class MMWeightGGUFQ4K(MMWeightGGUFTemplate):
     def __init__(self, weight_name, bias_name, lazy_load=False, lazy_load_file=None):
         super().__init__(weight_name, bias_name, lazy_load, lazy_load_file)
 
+@MM_WEIGHT_REGISTER("W-int4-group128-sym-Marlin")
+class MMWeightWint4group128Marlin(MMWeightQuantTemplate):
+    """
+    Name: "W-int4-group128-sym-Marlin
+
+    Quant int4 x FP16:
+        Weight: int4 pergroup sym
+        Kernel: Marlin
+    """
+
+    def __init__(self, weight_name, bias_name, lazy_load=False, lazy_load_file=None):
+        super().__init__(weight_name, bias_name, lazy_load, lazy_load_file)
+        self.load_func = self.load_quantized
+
+    def load(self, weight_dict):
+        assert not self.lazy_load
+        self.load_func(weight_dict)
+        self.workspace = weight_dict[f"{self.weight_name}_workspace"]
+        if self.bias_name is not None:
+            self.bias = weight_dict[self.bias_name]
+            self.pinned_bias = torch.empty(self.bias.shape, pin_memory=True, dtype=self.bias.dtype)
+        else:
+            self.bias = None
+    
+    def apply(self, input_tensor):
+        output_tensor = torch.empty(input_tensor.shape[:-1] + (self.weight_scale.shape[1],), dtype=input_tensor.dtype, device=input_tensor.device)
+        marlin_cuda_quant.mul(input_tensor, self.weight, output_tensor, self.weight_scale.half(), self.workspace, -1, -1, -1, -1)
+        if hasattr(self, "bias") and self.bias is not None:
+            output_tensor.add_(self.bias)
+        return output_tensor
     
 if __name__ == "__main__":
     weight_dict = {

lightx2v/models/networks/wan/causvid_model.py

@@ -37,7 +37,7 @@ class WanCausVidModel(WanModel):
         if os.path.exists(safetensors_path):
             with safe_open(safetensors_path, framework="pt") as f:
                 weight_dict = {
-                    key: (f.get_tensor(key).to(GET_DTYPE()) if unified_dtype or all(s not in key for s in sensitive_layer) else f.get_tensor(key)).pin_memory().to(self.device) for key in f.keys()
+                    key: (f.get_tensor(key).to(GET_DTYPE()) if unified_dtype or all(s not in key for s in sensitive_layer) else f.get_tensor(key).to(GET_SENSITIVE_DTYPE())).pin_memory().to(self.device) for key in f.keys()
                 }
                 return weight_dict
 

lightx2v/models/networks/wan/model.py

 import os
-
+import json
 import torch
 import torch.distributed as dist
 from loguru import logger
@@ -103,7 +103,7 @@ class WanModel:
 
     def _load_safetensor_to_dict(self, file_path, unified_dtype, sensitive_layer):
         with safe_open(file_path, framework="pt") as f:
-            return {key: (f.get_tensor(key).to(GET_DTYPE()) if unified_dtype or all(s not in key for s in sensitive_layer) else f.get_tensor(key)).pin_memory().to(self.device) for key in f.keys()}
+            return {key: (f.get_tensor(key).to(GET_DTYPE()) if unified_dtype or all(s not in key for s in sensitive_layer) else f.get_tensor(key).to(GET_SENSITIVE_DTYPE())).pin_memory().to(self.device) for key in f.keys()}
 
     def _load_ckpt(self, unified_dtype, sensitive_layer):
         safetensors_path = find_hf_model_path(self.config, self.model_path, "dit_original_ckpt", subdir="original")
@@ -134,11 +134,11 @@ class WanModel:
             with safe_open(safetensor_path, framework="pt") as f:
                 logger.info(f"Loading weights from {safetensor_path}")
                 for k in f.keys():
-                    if f.get_tensor(k).dtype == torch.float:
+                    if f.get_tensor(k).dtype in [torch.float16, torch.bfloat16, torch.float]:
                         if unified_dtype or all(s not in k for s in sensitive_layer):
                             weight_dict[k] = f.get_tensor(k).pin_memory().to(GET_DTYPE()).to(self.device)
                         else:
-                            weight_dict[k] = f.get_tensor(k).pin_memory().to(self.device)
+                            weight_dict[k] = f.get_tensor(k).pin_memory().to(GET_SENSITIVE_DTYPE()).to(self.device)
                     else:
                         weight_dict[k] = f.get_tensor(k).pin_memory().to(self.device)
 
@@ -152,11 +152,11 @@ class WanModel:
         safetensor_path = os.path.join(lazy_load_model_path, "non_block.safetensors")
         with safe_open(safetensor_path, framework="pt", device="cpu") as f:
             for k in f.keys():
-                if f.get_tensor(k).dtype == torch.float:
+                if f.get_tensor(k).dtype in [torch.float16, torch.bfloat16, torch.float]:
                     if unified_dtype or all(s not in k for s in sensitive_layer):
                         pre_post_weight_dict[k] = f.get_tensor(k).pin_memory().to(GET_DTYPE()).to(self.device)
                     else:
-                        pre_post_weight_dict[k] = f.get_tensor(k).pin_memory().to(self.device)
+                        pre_post_weight_dict[k] = f.get_tensor(k).pin_memory().to(GET_SENSITIVE_DTYPE()).to(self.device)
                 else:
                     pre_post_weight_dict[k] = f.get_tensor(k).pin_memory().to(self.device)