Support fp8_scaled diffusion models that don't use fp8 matrix mult.

comfy/model_base.py

@@ -108,7 +108,7 @@ class BaseModel(torch.nn.Module):
 
         if not unet_config.get("disable_unet_model_creation", False):
             if model_config.custom_operations is None:
-                fp8 = model_config.optimizations.get("fp8", model_config.scaled_fp8 is not None)
+                fp8 = model_config.optimizations.get("fp8", False)
                 operations = comfy.ops.pick_operations(unet_config.get("dtype", None), self.manual_cast_dtype, fp8_optimizations=fp8, scaled_fp8=model_config.scaled_fp8)
             else:
                 operations = model_config.custom_operations

comfy/model_detection.py

@@ -471,6 +471,10 @@ def model_config_from_unet(state_dict, unet_key_prefix, use_base_if_no_match=Fal
         model_config.scaled_fp8 = scaled_fp8_weight.dtype
         if model_config.scaled_fp8 == torch.float32:
             model_config.scaled_fp8 = torch.float8_e4m3fn
+        if scaled_fp8_weight.nelement() == 2:
+            model_config.optimizations["fp8"] = False
+        else:
+            model_config.optimizations["fp8"] = True
 
     return model_config
 

comfy/ops.py

@@ -17,6 +17,7 @@
 """
 
 import torch
+import logging
 import comfy.model_management
 from comfy.cli_args import args, PerformanceFeature
 import comfy.float
@@ -308,6 +309,7 @@ class fp8_ops(manual_cast):
             return torch.nn.functional.linear(input, weight, bias)
 
 def scaled_fp8_ops(fp8_matrix_mult=False, scale_input=False, override_dtype=None):
+    logging.info("Using scaled fp8: fp8 matrix mult: {}, scale input: {}".format(fp8_matrix_mult, scale_input))
     class scaled_fp8_op(manual_cast):
         class Linear(manual_cast.Linear):
             def __init__(self, *args, **kwargs):
@@ -358,7 +360,7 @@ def scaled_fp8_ops(fp8_matrix_mult=False, scale_input=False, override_dtype=None
 def pick_operations(weight_dtype, compute_dtype, load_device=None, disable_fast_fp8=False, fp8_optimizations=False, scaled_fp8=None):
     fp8_compute = comfy.model_management.supports_fp8_compute(load_device)
     if scaled_fp8 is not None:
-        return scaled_fp8_ops(fp8_matrix_mult=fp8_compute, scale_input=True, override_dtype=scaled_fp8)
+        return scaled_fp8_ops(fp8_matrix_mult=fp8_compute and fp8_optimizations, scale_input=True, override_dtype=scaled_fp8)
 
     if (
         fp8_compute and