[Model] Support for Spark2_5ForCausalLM implementation (#27868)

* Add Spark3 Model
* rename spark3 -> spark2_5

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@huggingface.co>
Co-authored-by: dongjiang <dongjiang2010@gmail.com>

conversion/__init__.py

@@ -255,6 +255,7 @@ TEXT_MODEL_MAP: dict[str, str] = {
     "SeedOssForCausalLM": "olmo",
     "SmallThinkerForCausalLM": "smallthinker",
     "SmolLM3ForCausalLM": "llama",
+    "Spark2_5ForCausalLM": "spark2_5",
     "SolarOpenForCausalLM": "glm",
     "StableLMEpochForCausalLM": "stablelm",
     "StableLmForCausalLM": "stablelm",

conversion/base.py

@@ -1543,6 +1543,9 @@ class TextModel(ModelBase):
         if chkhsh == "9e454714343b69b99b71795c1d27a68c2a1d15dab111f4d353109f966af29da7":
             # ref: https://huggingface.co/LiquidAI/LFM2.5-8B-A1B
             res = "lfm2"
+        if chkhsh == "0a766d034107bc736a3f2dc4968fd62e54a3570f1454443e0c5a4cc6bd7941ed":
+            # ref: https://huggingface.co/XHToken/Spark-X2.5-1.7B
+            res = "spark2_5"
         if chkhsh == "0ef9807a4087ebef797fc749390439009c3b9eda9ad1a097abbe738f486c01e5":
             # ref: https://huggingface.co/meta-llama/Meta-Llama-3-8B
             res = "llama-bpe"

conversion/spark2_5.py

@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+from collections.abc import Iterable
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from torch import Tensor
+
+from .base import ModelBase, TextModel, gguf
+
+
+@ModelBase.register("Spark2_5ForCausalLM")
+@ModelBase.example("XHToken/Spark-X2.5-1.7B")
+class Spark2_5Model(TextModel):
+    model_arch = gguf.MODEL_ARCH.SPARK2_5
+
+    def set_gguf_parameters(self) -> None:
+        super().set_gguf_parameters()
+
+        hparams = self.hparams
+        layer_types = hparams["layer_types"]
+        if len(layer_types) != self.block_count:
+            raise ValueError(
+                f"Spark2_5 layer_types length {len(layer_types)} != num_hidden_layers {self.block_count}"
+            )
+        if any(layer_type not in ("sliding_attention", "full_attention") for layer_type in layer_types):
+            raise ValueError(f"Spark2_5 has unsupported layer_types: {layer_types}")
+        if hparams.get("gate_attn_act_mode") != "sigmoid" or hparams.get("headwise_attn_output_gate") is not True:
+            raise ValueError("Spark2_5 conversion requires head-wise sigmoid attention gates")
+        if hparams.get("hidden_act") != "gelu":
+            raise ValueError(f"Spark2_5 conversion requires GELU, got {hparams.get('hidden_act')!r}")
+
+        self.gguf_writer.add_vocab_size(hparams["vocab_size"])
+        self.gguf_writer.add_sliding_window(hparams["sliding_window"])
+        self.gguf_writer.add_sliding_window_pattern(
+            [layer_type == "sliding_attention" for layer_type in layer_types]
+        )
+
+        head_dim = hparams["head_dim"]
+        full_rope = self.rope_parameters["full_attention"]
+        swa_rope = self.rope_parameters["sliding_attention"]
+        self.gguf_writer.add_rope_dimension_count(
+            int(head_dim * float(full_rope["partial_rotary_factor"]))
+        )
+        self.gguf_writer.add_rope_dimension_count_swa(
+            int(head_dim * float(swa_rope["partial_rotary_factor"]))
+        )
+
+    def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
+        if name.endswith(".self_attn.q_k_v_proj.weight"):
+            if bid is None:
+                raise ValueError(f"Spark2_5 fused QKV tensor has no block id: {name}")
+            yield self.format_tensor_name(gguf.MODEL_TENSOR.ATTN_QKV, bid), data_torch
+            return
+
+        if name.endswith(".self_attn.g_proj.weight"):
+            if bid is None:
+                raise ValueError(f"Spark2_5 attention gate tensor has no block id: {name}")
+            expected = self.hparams["num_attention_heads"]
+            if data_torch.shape[0] != expected:
+                raise ValueError(
+                    f"Spark2_5 layer {bid} attention gate width {data_torch.shape[0]} != head count {expected}"
+                )
+
+        yield from super().modify_tensors(data_torch, name, bid)