WIP: initial multimodal-gen support (#12484)

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python/sglang/multimodal_gen/configs/models/dits/base.py

@@ -0,0 +1,69 @@
+# Copied and adapted from: https://github.com/hao-ai-lab/FastVideo
+
+# SPDX-License-Identifier: Apache-2.0
+from dataclasses import dataclass, field
+from typing import Any
+
+from sglang.multimodal_gen.configs.models.base import ArchConfig, ModelConfig
+from sglang.multimodal_gen.runtime.layers.quantization import QuantizationConfig
+from sglang.multimodal_gen.runtime.platforms import AttentionBackendEnum
+
+
+@dataclass
+class DiTArchConfig(ArchConfig):
+    _fsdp_shard_conditions: list = field(default_factory=list)
+    _compile_conditions: list = field(default_factory=list)
+    param_names_mapping: dict = field(default_factory=dict)
+    reverse_param_names_mapping: dict = field(default_factory=dict)
+    lora_param_names_mapping: dict = field(default_factory=dict)
+    _supported_attention_backends: set[AttentionBackendEnum] = field(
+        default_factory=lambda: {
+            AttentionBackendEnum.SLIDING_TILE_ATTN,
+            AttentionBackendEnum.SAGE_ATTN,
+            AttentionBackendEnum.FA3,
+            AttentionBackendEnum.TORCH_SDPA,
+            AttentionBackendEnum.VIDEO_SPARSE_ATTN,
+            AttentionBackendEnum.VMOBA_ATTN,
+            AttentionBackendEnum.SAGE_ATTN_THREE,
+        }
+    )
+
+    hidden_size: int = 0
+    num_attention_heads: int = 0
+    num_channels_latents: int = 0
+    exclude_lora_layers: list[str] = field(default_factory=list)
+    boundary_ratio: float | None = None
+
+    def __post_init__(self) -> None:
+        if not self._compile_conditions:
+            self._compile_conditions = self._fsdp_shard_conditions.copy()
+
+
+@dataclass
+class DiTConfig(ModelConfig):
+    arch_config: DiTArchConfig = field(default_factory=DiTArchConfig)
+
+    # sgl-diffusionDiT-specific parameters
+    prefix: str = ""
+    quant_config: QuantizationConfig | None = None
+
+    @staticmethod
+    def add_cli_args(parser: Any, prefix: str = "dit-config") -> Any:
+        """Add CLI arguments for DiTConfig fields"""
+        parser.add_argument(
+            f"--{prefix}.prefix",
+            type=str,
+            dest=f"{prefix.replace('-', '_')}.prefix",
+            default=DiTConfig.prefix,
+            help="Prefix for the DiT model",
+        )
+
+        parser.add_argument(
+            f"--{prefix}.quant-config",
+            type=str,
+            dest=f"{prefix.replace('-', '_')}.quant_config",
+            default=None,
+            help="Quantization configuration for the DiT model",
+        )
+
+        return parser