[Model] Add huggingface skt/A.X-K1 model (#32407)

Signed-off-by: Sungwan(Alex) Kim <sw0726.kim@sktelecom.com>
Signed-off-by: fort726 <38447663+fort726@users.noreply.github.com>
Co-authored-by: Sungwan(Alex) Kim <sw0726.kim@sktelecom.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: TJian <tunjian.tan@embeddedllm.com>

docs/models/supported_models.md

@@ -369,6 +369,7 @@ th {
 | `AquilaForCausalLM` | Aquila, Aquila2 | `BAAI/Aquila-7B`, `BAAI/AquilaChat-7B`, etc. | ✅︎ | ✅︎ |
 | `ArceeForCausalLM` | Arcee (AFM) | `arcee-ai/AFM-4.5B-Base`, etc. | ✅︎ | ✅︎ |
 | `ArcticForCausalLM` | Arctic | `Snowflake/snowflake-arctic-base`, `Snowflake/snowflake-arctic-instruct`, etc. | | ✅︎ |
+| `AXK1ForCausalLM` | A.X-K1 | `skt/A.X-K1`, etc. | | ✅︎ |
 | `BaiChuanForCausalLM` | Baichuan2, Baichuan | `baichuan-inc/Baichuan2-13B-Chat`, `baichuan-inc/Baichuan-7B`, etc. | ✅︎ | ✅︎ |
 | `BailingMoeForCausalLM` | Ling | `inclusionAI/Ling-lite-1.5`, `inclusionAI/Ling-plus`, etc. | ✅︎ | ✅︎ |
 | `BailingMoeV2ForCausalLM` | Ling | `inclusionAI/Ling-mini-2.0`, etc. | ✅︎ | ✅︎ |

tests/models/registry.py

@@ -194,6 +194,7 @@ _TEXT_GENERATION_EXAMPLE_MODELS = {
     "ArcticForCausalLM": _HfExamplesInfo(
         "Snowflake/snowflake-arctic-instruct", trust_remote_code=True
     ),
+    "AXK1ForCausalLM": _HfExamplesInfo("skt/A.X-K1", trust_remote_code=True),
     "BaiChuanForCausalLM": _HfExamplesInfo(
         "baichuan-inc/Baichuan-7B", trust_remote_code=True
     ),

vllm/model_executor/models/AXK1.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+# Adapted from
+# https://github.com/huggingface/transformers/blob/v4.28.0/src/transformers/models/llama/modeling_llama.py
+# Copyright 2023 The vLLM team.
+#
+# This code is based on EleutherAI's GPT-NeoX library and the GPT-NeoX
+# and OPT implementations in this library. It has been modified from its
+# original forms to accommodate minor architectural differences compared
+# to GPT-NeoX and OPT used by the Meta AI team that trained the model.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Inference-only A.X K1 model."""
+
+import typing
+from collections.abc import Callable, Iterable
+from itertools import islice
+
+import torch
+from torch import nn
+
+from vllm._aiter_ops import rocm_aiter_ops
+from vllm.compilation.decorators import support_torch_compile
+from vllm.config import CacheConfig, ParallelConfig, VllmConfig
+from vllm.distributed import (
+    get_ep_group,
+    get_pp_group,
+    get_tensor_model_parallel_rank,
+    get_tensor_model_parallel_world_size,
+    tensor_model_parallel_all_gather,
+)
+from vllm.logger import init_logger
+from vllm.model_executor.layers.attention import Attention
+from vllm.model_executor.layers.fused_moe import SharedFusedMoE
+from vllm.model_executor.layers.layernorm import RMSNorm
+from vllm.model_executor.layers.linear import (
+    ColumnParallelLinear,
+    MergedColumnParallelLinear,
+    ReplicatedLinear,
+    RowParallelLinear,
+)
+from vllm.model_executor.layers.logits_processor import LogitsProcessor
+from vllm.model_executor.layers.mla import MLAModules, MultiHeadLatentAttentionWrapper
+from vllm.model_executor.layers.quantization import QuantizationConfig
+from vllm.model_executor.layers.rotary_embedding import get_rope
+from vllm.model_executor.layers.vocab_parallel_embedding import (
+    ParallelLMHead,
+    VocabParallelEmbedding,
+)
+from vllm.model_executor.model_loader.weight_utils import (
+    default_weight_loader,
+    maybe_remap_kv_scale_name,
+)
+from vllm.model_executor.models.deepseek_v2 import (
+    DeepseekAttention,
+    DeepseekV2MLP,
+    yarn_get_mscale,
+)
+from vllm.model_executor.models.utils import sequence_parallel_chunk
+from vllm.platforms import current_platform
+from vllm.sequence import IntermediateTensors
+from vllm.transformers_utils.configs.AXK1 import AXK1Config
+
+from .interfaces import MixtureOfExperts, SupportsEagle, SupportsLoRA, SupportsPP
+from .utils import (
+    PPMissingLayer,
+    is_pp_missing_parameter,
+    make_empty_intermediate_tensors_factory,
+    make_layers,
+    maybe_prefix,
+)
+
+logger = init_logger(__name__)
+
+
+class AXK1MLP(DeepseekV2MLP):
+    pass
+
+
+class AXK1MoE(nn.Module):
+    def __init__(
+        self,
+        config: AXK1Config,
+        parallel_config: ParallelConfig,
+        quant_config: QuantizationConfig | None = None,
+        prefix: str = "",
+    ):
+        super().__init__()
+        self.tp_size = get_tensor_model_parallel_world_size()
+        self.tp_rank = get_tensor_model_parallel_rank()
+
+        self.routed_scaling_factor = config.routed_scaling_factor
+
+        self.ep_group = get_ep_group().device_group
+        self.ep_rank = get_ep_group().rank_in_group
+        self.ep_size = self.ep_group.size()
+        self.n_routed_experts: int = config.n_routed_experts
+        self.n_shared_experts: int = config.n_shared_experts
+
+        self.is_sequence_parallel = parallel_config.use_sequence_parallel_moe
+
+        if config.hidden_act != "silu":
+            raise ValueError(
+                f"Unsupported activation: {config.hidden_act}. "
+                "Only silu is supported for now."
+            )
+
+        self.gate = ReplicatedLinear(
+            config.hidden_size,
+            config.n_routed_experts,
+            bias=False,
+            quant_config=None,
+            prefix=f"{prefix}.gate",
+        )
+        if config.topk_method == "noaux_tc":
+            self.gate.e_score_correction_bias = nn.Parameter(
+                torch.empty(config.n_routed_experts, dtype=torch.float32)
+            )
+        else:
+            self.gate.e_score_correction_bias = None
+
+        # Load balancing settings.
+        eplb_config = parallel_config.eplb_config
+        self.enable_eplb = parallel_config.enable_eplb
+
+        self.n_redundant_experts = eplb_config.num_redundant_experts
+        self.n_logical_experts = self.n_routed_experts
+        self.n_physical_experts = self.n_logical_experts + self.n_redundant_experts
+        self.n_local_physical_experts = self.n_physical_experts // self.ep_size
+
+        self.physical_expert_start = self.ep_rank * self.n_local_physical_experts
+        self.physical_expert_end = (
+            self.physical_expert_start + self.n_local_physical_experts
+        )
+
+        self.is_rocm_aiter_moe_enabled = rocm_aiter_ops.is_fused_moe_enabled()
+        self.is_fusion_moe_shared_experts_enabled = (
+            rocm_aiter_ops.is_fusion_moe_shared_experts_enabled()
+        )
+        if config.n_shared_experts is None or self.is_fusion_moe_shared_experts_enabled:
+            self.shared_experts = None
+        else:
+            intermediate_size = config.moe_intermediate_size * config.n_shared_experts
+
+            self.shared_experts = AXK1MLP(
+                hidden_size=config.hidden_size,
+                intermediate_size=intermediate_size,
+                hidden_act=config.hidden_act,
+                quant_config=quant_config,
+                is_sequence_parallel=self.is_sequence_parallel,
+                reduce_results=False,
+                prefix=f"{prefix}.shared_experts",
+            )
+
+        self.experts = SharedFusedMoE(
+            shared_experts=self.shared_experts,
+            gate=self.gate,
+            num_experts=config.n_routed_experts,
+            top_k=config.num_experts_per_tok,
+            hidden_size=config.hidden_size,
+            intermediate_size=config.moe_intermediate_size,
+            reduce_results=False,
+            renormalize=config.norm_topk_prob,
+            quant_config=quant_config,
+            use_grouped_topk=True,
+            num_expert_group=config.n_group,
+            topk_group=config.topk_group,
+            prefix=f"{prefix}.experts",
+            scoring_func=config.scoring_func,
+            # we do scaling outside, set factor to 1.0 to avoid double mul
+            # aiter applies routed_scaling_factor internally
+            routed_scaling_factor=1.0
+            if not self.is_rocm_aiter_moe_enabled
+            else self.routed_scaling_factor,
+            e_score_correction_bias=self.gate.e_score_correction_bias,
+            enable_eplb=self.enable_eplb,
+            num_redundant_experts=self.n_redundant_experts,
+            is_sequence_parallel=self.is_sequence_parallel,
+            n_shared_experts=config.n_shared_experts
+            if self.is_fusion_moe_shared_experts_enabled
+            else None,
+        )
+
+    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
+        num_tokens, hidden_dim = hidden_states.shape
+        hidden_states = hidden_states.view(-1, hidden_dim)
+
+        # Chunk the hidden states so they aren't replicated across TP ranks.
+        # This avoids duplicate computation in self.experts.
+        # TODO: We can replace the all_reduce at the end of attn with a
+        # reduce_scatter instead of chunking here.
+        if self.is_sequence_parallel:
+            hidden_states = sequence_parallel_chunk(hidden_states)
+
+        if self.experts.is_internal_router:
+            # In this case, the gate/router runs inside the FusedMoE class
+            fused_moe_out = self.experts(
+                hidden_states=hidden_states, router_logits=hidden_states
+            )
+        else:
+            # router_logits: (num_tokens, n_experts)
+            router_logits, _ = self.gate(hidden_states)
+            fused_moe_out = self.experts(
+                hidden_states=hidden_states, router_logits=router_logits
+            )
+
+        shared_output, final_hidden_states = fused_moe_out
+        if self.shared_experts is None:
+            assert shared_output is None
+
+        # Fix FP16 overflow
+        # See AXK1DecoderLayer for more details.
+        if hidden_states.dtype != torch.float16:
+            if not self.is_rocm_aiter_moe_enabled:
+                final_hidden_states *= self.routed_scaling_factor
+        elif self.shared_experts is not None:
+            assert shared_output is not None
+            shared_output *= 1.0 / self.routed_scaling_factor
+
+        if self.shared_experts is not None:
+            assert shared_output is not None
+            final_hidden_states += shared_output
+
+        if self.is_sequence_parallel:
+            final_hidden_states = tensor_model_parallel_all_gather(
+                final_hidden_states, 0
+            )
+            final_hidden_states = final_hidden_states[:num_tokens]
+        elif self.tp_size > 1:
+            final_hidden_states = self.experts.maybe_all_reduce_tensor_model_parallel(
+                final_hidden_states
+            )
+
+        return final_hidden_states.view(num_tokens, hidden_dim)
+
+
+def _get_llama_4_scaling(
+    original_max_position_embeddings: int, scaling_beta: float, positions: torch.Tensor
+) -> torch.Tensor:
+    scaling = 1 + scaling_beta * torch.log(
+        1 + torch.floor(positions / original_max_position_embeddings)
+    )
+    # Broadcast over num_heads and head_dim
+    return scaling[..., None, None]
+
+
+class AXK1Attention(nn.Module):
+    def __init__(
+        self,
+        vllm_config: VllmConfig,
+        config: AXK1Config,
+        hidden_size: int,
+        num_heads: int,
+        qk_nope_head_dim: int,
+        qk_rope_head_dim: int,
+        v_head_dim: int,
+        q_lora_rank: int,
+        kv_lora_rank: int,
+        max_position_embeddings: int = 8192,
+        cache_config: CacheConfig | None = None,
+        quant_config: QuantizationConfig | None = None,
+        topk_indices_buffer: torch.Tensor | None = None,
+        prefix: str = "",
+    ) -> None:
+        super().__init__()
+        self.hidden_size = hidden_size
+        self.qk_nope_head_dim = qk_nope_head_dim
+        self.qk_rope_head_dim = qk_rope_head_dim
+        self.qk_head_dim = qk_nope_head_dim + qk_rope_head_dim
+        self.v_head_dim = v_head_dim
+        self.q_lora_rank = q_lora_rank
+        self.kv_lora_rank = kv_lora_rank
+        self.num_heads = num_heads
+        tp_size = get_tensor_model_parallel_world_size()
+        assert num_heads % tp_size == 0
+        self.num_local_heads = num_heads // tp_size
+        self.scaling = self.qk_head_dim**-0.5
+        self.max_position_embeddings = max_position_embeddings
+        assert topk_indices_buffer is None, (
+            "topk_indices_buffer is not \
+        supported for AXK1Attention"
+        )
+
+        if self.q_lora_rank is not None:
+            self.q_a_proj = ReplicatedLinear(
+                self.hidden_size,
+                self.q_lora_rank,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.q_a_proj",
+            )
+            self.q_a_layernorm = RMSNorm(self.q_lora_rank, eps=config.rms_norm_eps)
+            self.q_b_proj = ColumnParallelLinear(
+                q_lora_rank,
+                self.num_heads * self.qk_head_dim,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.q_b_proj",
+            )
+        else:
+            self.q_proj = ColumnParallelLinear(
+                self.hidden_size,
+                self.num_heads * self.qk_head_dim,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.q_proj",
+            )
+
+        self.kv_a_proj_with_mqa = ReplicatedLinear(
+            self.hidden_size,
+            self.kv_lora_rank + self.qk_rope_head_dim,
+            bias=False,
+            quant_config=quant_config,
+            prefix=f"{prefix}.kv_a_proj_with_mqa",
+        )
+        self.kv_a_layernorm = RMSNorm(self.kv_lora_rank, eps=config.rms_norm_eps)
+        self.kv_b_proj = ColumnParallelLinear(
+            self.kv_lora_rank,
+            self.num_heads * (self.qk_nope_head_dim + self.v_head_dim),
+            bias=False,
+            quant_config=quant_config,
+            prefix=f"{prefix}.kv_b_proj",
+        )
+        # O projection.
+        self.o_proj = RowParallelLinear(
+            self.num_heads * self.v_head_dim,
+            self.hidden_size,
+            bias=False,
+            quant_config=quant_config,
+            prefix=f"{prefix}.o_proj",
+        )
+        if config.rope_parameters["rope_type"] != "default":
+            config.rope_parameters["rope_type"] = (
+                "deepseek_yarn"
+                if config.rope_parameters.get("apply_yarn_scaling", True)
+                else "deepseek_llama_scaling"
+            )
+
+        self.rotary_emb = get_rope(
+            qk_rope_head_dim,
+            max_position=max_position_embeddings,
+            rope_parameters=config.rope_parameters,
+            is_neox_style=False,
+        )
+
+        if config.rope_parameters["rope_type"] == "deepseek_yarn":
+            mscale_all_dim = config.rope_parameters.get("mscale_all_dim", False)
+            scaling_factor = config.rope_parameters["factor"]
+            mscale = yarn_get_mscale(scaling_factor, float(mscale_all_dim))
+            self.scaling = self.scaling * mscale * mscale
+
+        self.attn = Attention(
+            self.num_local_heads,
+            self.qk_head_dim,
+            self.scaling,
+            num_kv_heads=self.num_local_heads,
+            cache_config=cache_config,
+            quant_config=quant_config,
+            prefix=f"{prefix}.attn",
+        )
+
+    def forward(
+        self,
+        positions: torch.Tensor,
+        hidden_states: torch.Tensor,
+        llama_4_scaling: torch.Tensor | None,
+    ) -> torch.Tensor:
+        if self.q_lora_rank is not None:
+            q = self.q_a_proj(hidden_states)[0]
+            q = self.q_a_layernorm(q)
+            q = self.q_b_proj(q)[0].view(-1, self.num_local_heads, self.qk_head_dim)
+        else:
+            q = self.q_proj(hidden_states)[0].view(
+                -1, self.num_local_heads, self.qk_head_dim
+            )
+        q_nope, q_pe = q.split([self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
+        latent_cache = self.kv_a_proj_with_mqa(hidden_states)[0]
+        kv_a, _ = latent_cache.split([self.kv_lora_rank, self.qk_rope_head_dim], dim=-1)
+        latent_cache = latent_cache.unsqueeze(1)
+        kv_a = self.kv_a_layernorm(kv_a)
+        kv = self.kv_b_proj(kv_a)[0]
+        kv = kv.view(-1, self.num_local_heads, self.qk_nope_head_dim + self.v_head_dim)
+        k_nope, v = kv.split([self.qk_nope_head_dim, self.v_head_dim], dim=-1)
+        k_pe = latent_cache[:, :, self.kv_lora_rank :]
+
+        q_pe, k_pe = self.rotary_emb(positions, q_pe, k_pe)
+
+        q[..., self.qk_nope_head_dim :] = q_pe
+        k = torch.empty_like(q)
+        k[..., : self.qk_nope_head_dim] = k_nope
+        k[..., self.qk_nope_head_dim :] = k_pe
+
+        # Apply llama 4 scaling if provided
+        if llama_4_scaling is not None:
+            q *= llama_4_scaling
+
+        # padding value to qk_head_dim for alignment
+        v = torch.nn.functional.pad(
+            v, [0, self.qk_head_dim - self.v_head_dim], value=0
+        ).view(-1, self.num_local_heads * self.qk_head_dim)
+        attn_output = self.attn(q, k, v)
+        attn_output = attn_output.view(-1, self.num_local_heads, self.qk_head_dim)[
+            ..., : self.v_head_dim
+        ].reshape(-1, self.num_local_heads * self.v_head_dim)
+        output, _ = self.o_proj(attn_output)
+        return output
+
+
+class AXK1MLAAttention(nn.Module):
+    """
+    Main reference: DeepseekV2 paper, and FlashInfer Implementation
+    (https://arxiv.org/abs/2405.04434 and https://github.com/flashinfer-ai/flashinfer/pull/551).
+
+        For more info see MLACommonImpl in:
+        vllm/v1/attention/backends/mla/utils.py
+    """
+
+    def __init__(
+        self,
+        vllm_config: VllmConfig,
+        config: AXK1Config,
+        hidden_size: int,
+        num_heads: int,
+        qk_nope_head_dim: int,
+        qk_rope_head_dim: int,
+        v_head_dim: int,
+        q_lora_rank: int | None,
+        kv_lora_rank: int,
+        max_position_embeddings: int = 8192,
+        cache_config: CacheConfig | None = None,
+        quant_config: QuantizationConfig | None = None,
+        prefix: str = "",
+        topk_indices_buffer: torch.Tensor | None = None,
+    ) -> None:
+        super().__init__()
+        self.hidden_size = hidden_size
+        self.qk_nope_head_dim = qk_nope_head_dim
+        self.qk_rope_head_dim = qk_rope_head_dim
+        self.qk_head_dim = qk_nope_head_dim + qk_rope_head_dim
+        self.v_head_dim = v_head_dim
+
+        self.q_lora_rank = q_lora_rank
+        self.kv_lora_rank = kv_lora_rank
+
+        self.num_heads = num_heads
+        tp_size = get_tensor_model_parallel_world_size()
+        assert num_heads % tp_size == 0
+        self.num_local_heads = num_heads // tp_size
+
+        self.scaling = self.qk_head_dim**-0.5
+        self.max_position_embeddings = max_position_embeddings
+
+        if self.q_lora_rank is not None:
+            self.fused_qkv_a_proj = MergedColumnParallelLinear(
+                self.hidden_size,
+                [self.q_lora_rank, self.kv_lora_rank + self.qk_rope_head_dim],
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.fused_qkv_a_proj",
+                disable_tp=True,
+            )
+        else:
+            self.kv_a_proj_with_mqa = ReplicatedLinear(
+                self.hidden_size,
+                self.kv_lora_rank + self.qk_rope_head_dim,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.kv_a_proj_with_mqa",
+            )
+
+        if self.q_lora_rank is not None:
+            self.q_a_layernorm = RMSNorm(self.q_lora_rank, eps=config.rms_norm_eps)
+            self.q_b_proj = ColumnParallelLinear(
+                self.q_lora_rank,
+                self.num_heads * self.qk_head_dim,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.q_b_proj",
+            )
+        else:
+            self.q_proj = ColumnParallelLinear(
+                self.hidden_size,
+                self.num_heads * self.qk_head_dim,
+                bias=False,
+                quant_config=quant_config,
+                prefix=f"{prefix}.q_proj",
+            )
+        self.kv_a_layernorm = RMSNorm(self.kv_lora_rank, eps=config.rms_norm_eps)
+        self.kv_b_proj = ColumnParallelLinear(
+            self.kv_lora_rank,
+            self.num_heads * (self.qk_nope_head_dim + self.v_head_dim),
+            bias=False,
+            quant_config=quant_config,
+            prefix=f"{prefix}.kv_b_proj",
+        )
+        self.o_proj = RowParallelLinear(
+            self.num_heads * self.v_head_dim,
+            self.hidden_size,
+            bias=False,
+            quant_config=quant_config,
+            prefix=f"{prefix}.o_proj",
+        )
+
+        if config.rope_parameters["rope_type"] != "default":
+            config.rope_parameters["rope_type"] = (
+                "deepseek_yarn"
+                if config.rope_parameters.get("apply_yarn_scaling", True)
+                else "deepseek_llama_scaling"
+            )
+
+        self.rotary_emb = get_rope(
+            qk_rope_head_dim,
+            max_position=max_position_embeddings,
+            rope_parameters=config.rope_parameters,
+            is_neox_style=False,
+        )
+
+        if config.rope_parameters["rope_type"] == "deepseek_yarn":
+            mscale_all_dim = config.rope_parameters.get("mscale_all_dim", False)
+            scaling_factor = config.rope_parameters["factor"]
+            mscale = yarn_get_mscale(scaling_factor, float(mscale_all_dim))
+            self.scaling = self.scaling * mscale * mscale
+
+        mla_modules = MLAModules(
+            kv_a_layernorm=self.kv_a_layernorm,
+            kv_b_proj=self.kv_b_proj,
+            rotary_emb=self.rotary_emb,
+            o_proj=self.o_proj,
+            fused_qkv_a_proj=self.fused_qkv_a_proj
+            if self.q_lora_rank is not None
+            else None,
+            kv_a_proj_with_mqa=self.kv_a_proj_with_mqa
+            if self.q_lora_rank is None
+            else None,
+            q_a_layernorm=self.q_a_layernorm if self.q_lora_rank is not None else None,
+            q_b_proj=self.q_b_proj if self.q_lora_rank is not None else None,
+            q_proj=self.q_proj if self.q_lora_rank is None else None,
+            indexer=None,
+            indexer_rotary_emb=None,
+            is_sparse=False,
+            topk_indices_buffer=topk_indices_buffer,
+        )
+
+        self.mla_attn = MultiHeadLatentAttentionWrapper(
+            self.hidden_size,
+            self.num_local_heads,
+            self.scaling,
+            self.qk_nope_head_dim,
+            self.qk_rope_head_dim,
+            self.v_head_dim,
+            self.q_lora_rank,
+            self.kv_lora_rank,
+            mla_modules,
+            cache_config,
+            quant_config,
+            prefix,
+        )
+
+    def forward(
+        self,
+        positions: torch.Tensor,
+        hidden_states: torch.Tensor,
+        llama_4_scaling: torch.Tensor | None,
+    ) -> torch.Tensor:
+        return self.mla_attn(positions, hidden_states, llama_4_scaling)
+
+
+class AXK1DecoderLayer(nn.Module):
+    def __init__(
+        self,
+        vllm_config: VllmConfig,
+        prefix: str,
+        config: AXK1Config | None = None,
+    ) -> None:
+        super().__init__()
+
+        if config is None:
+            config = vllm_config.model_config.hf_config
+        model_config = vllm_config.model_config
+        cache_config = vllm_config.cache_config
+        quant_config = vllm_config.quant_config
+        parallel_config = vllm_config.parallel_config
+        self.config = config
+
+        self.hidden_size = config.hidden_size
+        max_position_embeddings = config.max_position_embeddings
+        # DecoderLayers are created with `make_layers` which passes the prefix
+        # with the layer's index.
+        layer_idx = int(prefix.split(sep=".")[-1])
+        self.layer_idx = layer_idx
+
+        # verify MLA attention specific fields
+        qk_nope_head_dim = config.qk_nope_head_dim
+        qk_rope_head_dim = config.qk_rope_head_dim
+        v_head_dim = config.v_head_dim
+        kv_lora_rank = config.kv_lora_rank
+        use_mha = all(dim == 0 for dim in (qk_nope_head_dim, qk_rope_head_dim))
+        self.use_mha = use_mha
+
+        if use_mha:
+            attn_cls = DeepseekAttention
+        elif model_config.use_mla:
+            attn_cls = AXK1MLAAttention
+        else:
+            attn_cls = AXK1Attention
+        self.self_attn = attn_cls(
+            vllm_config=vllm_config,
+            config=config,
+            hidden_size=self.hidden_size,
+            num_heads=config.num_attention_heads,
+            qk_nope_head_dim=qk_nope_head_dim,
+            qk_rope_head_dim=qk_rope_head_dim,
+            v_head_dim=v_head_dim,
+            q_lora_rank=config.q_lora_rank,
+            kv_lora_rank=kv_lora_rank,
+            max_position_embeddings=max_position_embeddings,
+            cache_config=cache_config,
+            quant_config=quant_config,
+            prefix=f"{prefix}.self_attn",
+            topk_indices_buffer=None,
+        )
+
+        self.is_layer_sparse = self._is_layer_sparse()
+        if self.is_layer_sparse:
+            self.mlp = AXK1MoE(
+                config=config,
+                parallel_config=parallel_config,
+                quant_config=quant_config,
+                prefix=f"{prefix}.mlp",
+            )
+        else:
+            self.mlp = AXK1MLP(
+                hidden_size=config.hidden_size,
+                intermediate_size=config.intermediate_size,
+                hidden_act=config.hidden_act,
+                quant_config=quant_config,
+                prefix=f"{prefix}.mlp",
+            )
+        self.input_layernorm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.post_attention_layernorm = RMSNorm(
+            config.hidden_size, eps=config.rms_norm_eps
+        )
+        self.post_mlp_layernorm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.routed_scaling_factor = config.routed_scaling_factor
+
+    def _is_layer_sparse(self) -> bool:
+        return (
+            self.config.n_routed_experts is not None
+            and self.layer_idx >= self.config.first_k_dense_replace
+            and self.layer_idx % self.config.moe_layer_freq == 0
+        )
+
+    def forward(
+        self,
+        positions: torch.Tensor,
+        hidden_states: torch.Tensor,
+        residual: torch.Tensor | None,
+        llama_4_scaling: torch.Tensor | None = None,
+    ) -> tuple[torch.Tensor, torch.Tensor]:
+        # Self Attention
+        if residual is None:
+            residual = hidden_states.clone()
+            hidden_states = self.input_layernorm(hidden_states)
+        else:
+            hidden_states, residual = self.input_layernorm(hidden_states, residual)
+
+        attn_kwargs = {
+            "positions": positions,
+            "hidden_states": hidden_states,
+        }
+        if not self.use_mha:
+            attn_kwargs["llama_4_scaling"] = llama_4_scaling
+        hidden_states = self.self_attn(**attn_kwargs)
+
+        if (
+            not isinstance(self.self_attn, DeepseekAttention)
+            and hidden_states.dtype == torch.float16
+        ):
+            # Fix FP16 overflow
+            # We scale both hidden_states and residual before
+            # rmsnorm, and rmsnorm result would not affect by scale.
+            hidden_states *= 1.0 / self.routed_scaling_factor
+            if self.layer_idx == 0:
+                # The residual is shared by all layers, we only scale it on
+                # first layer.
+                residual *= 1.0 / self.routed_scaling_factor
+
+        # Fully Connected
+        hidden_states, residual = self.post_attention_layernorm(hidden_states, residual)
+        hidden_states = self.mlp(hidden_states)
+
+        if self.is_layer_sparse:
+            hidden_states = self.post_mlp_layernorm(hidden_states)
+
+        if isinstance(self.mlp, AXK1MLP) and hidden_states.dtype == torch.float16:
+            # Fix FP16 overflow
+            # Scaling the AXK1MLP output, it is the input of
+            # input_layernorm of next decoder layer.
+            # The scaling of AXK1MOE output would be done in the forward
+            # of AXK1MOE
+            hidden_states *= 1.0 / self.routed_scaling_factor
+
+        return hidden_states, residual
+
+
+@support_torch_compile
+class AXK1Model(nn.Module):
+    fall_back_to_pt_during_load = False
+
+    def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
+        super().__init__()
+
+        config: AXK1Config = vllm_config.model_config.hf_config
+        quant_config = vllm_config.quant_config
+        self.config = config
+        self.device = current_platform.device_type
+        self.vocab_size = config.vocab_size
+
+        if get_pp_group().is_first_rank:
+            self.embed_tokens = VocabParallelEmbedding(
+                config.vocab_size,
+                config.hidden_size,
+                quant_config=quant_config,
+                prefix=f"{prefix}.embed_tokens",
+            )
+        else:
+            self.embed_tokens = PPMissingLayer()
+        self.start_layer, self.end_layer, self.layers = make_layers(
+            config.num_hidden_layers,
+            lambda prefix: AXK1DecoderLayer(vllm_config, prefix),
+            prefix=f"{prefix}.layers",
+        )
+
+        if get_pp_group().is_last_rank:
+            self.norm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        else:
+            self.norm = PPMissingLayer()
+        self.make_empty_intermediate_tensors = make_empty_intermediate_tensors_factory(
+            ["hidden_states", "residual"], config.hidden_size
+        )
+
+    def embed_input_ids(self, input_ids: torch.Tensor) -> torch.Tensor:
+        return self.embed_tokens(input_ids)
+
+    def forward(
+        self,
+        input_ids: torch.Tensor | None,
+        positions: torch.Tensor,
+        intermediate_tensors: IntermediateTensors | None,
+        inputs_embeds: torch.Tensor | None = None,
+    ) -> torch.Tensor | IntermediateTensors:
+        if get_pp_group().is_first_rank:
+            if inputs_embeds is not None:
+                hidden_states = inputs_embeds
+            else:
+                hidden_states = self.embed_input_ids(input_ids)
+            residual = None
+        else:
+            assert intermediate_tensors is not None
+            hidden_states = intermediate_tensors["hidden_states"]
+            residual = intermediate_tensors["residual"]
+
+        # Compute llama 4 scaling once per forward pass if enabled
+        llama_4_scaling_config = getattr(self.config, "llama_4_scaling", None)
+        llama_4_scaling: torch.Tensor | None
+        if llama_4_scaling_config is not None:
+            llama_4_scaling = _get_llama_4_scaling(
+                original_max_position_embeddings=llama_4_scaling_config[
+                    "original_max_position_embeddings"
+                ],
+                scaling_beta=llama_4_scaling_config["beta"],
+                positions=positions,
+            )
+        else:
+            llama_4_scaling = None
+
+        for layer in islice(self.layers, self.start_layer, self.end_layer):
+            hidden_states, residual = layer(
+                positions, hidden_states, residual, llama_4_scaling
+            )
+
+        if not get_pp_group().is_last_rank:
+            return IntermediateTensors(
+                {"hidden_states": hidden_states, "residual": residual}
+            )
+
+        hidden_states, _ = self.norm(hidden_states, residual)
+        return hidden_states
+
+
+class AXK1MixtureOfExperts(MixtureOfExperts):
+    moe_mlp_layers: list[AXK1MoE]
+    """
+    List of MoE MLP layers in the model.
+    """
+
+    def extract_moe_parameters(self, example_moe: AXK1MoE | None):
+        if example_moe is None:
+            self.num_moe_layers = 0
+            self.num_expert_groups = 0
+            self.num_logical_experts = 0
+            self.num_physical_experts = 0
+            self.num_local_physical_experts = 0
+            self.num_routed_experts = 0
+            self.num_shared_experts = 0
+            self.num_redundant_experts = 0
+            logger.warning("AXK1: No AXK1MoE layer found in model.layers.")
+        else:
+            self.num_logical_experts = example_moe.n_logical_experts
+            self.num_physical_experts = example_moe.n_physical_experts
+            self.num_local_physical_experts = example_moe.n_local_physical_experts
+            self.num_routed_experts = example_moe.n_routed_experts
+            self.num_shared_experts = example_moe.n_shared_experts
+            self.num_redundant_experts = example_moe.n_redundant_experts
+
+    def update_physical_experts_metadata(
+        self,
+        num_physical_experts: int,
+        num_local_physical_experts: int,
+    ) -> None:
+        assert self.num_local_physical_experts == num_local_physical_experts
+        self.num_physical_experts = num_physical_experts
+        self.num_local_physical_experts = num_local_physical_experts
+        self.num_redundant_experts = num_physical_experts - self.num_logical_experts
+        for moe in self.moe_mlp_layers:
+            moe.n_local_physical_experts = num_local_physical_experts
+            moe.n_physical_experts = num_physical_experts
+            moe.n_redundant_experts = self.num_redundant_experts
+            moe.experts.update_expert_map()
+
+
+class AXK1ForCausalLM(
+    nn.Module, SupportsPP, AXK1MixtureOfExperts, SupportsLoRA, SupportsEagle
+):
+    packed_modules_mapping = {
+        "gate_up_proj": ["gate_proj", "up_proj"],
+    }
+    model_cls = AXK1Model
+
+    def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
+        super().__init__()
+        config: AXK1Config = vllm_config.model_config.hf_config
+        quant_config = vllm_config.quant_config
+        self.config = config
+        self.quant_config = quant_config
+
+        qk_nope_head_dim = config.qk_nope_head_dim
+        qk_rope_head_dim = config.qk_rope_head_dim
+        self.use_mha = all(dim == 0 for dim in (qk_nope_head_dim, qk_rope_head_dim))
+
+        if self.use_mha:
+            self.packed_modules_mapping["qkv_proj"] = ["q_proj", "k_proj", "v_proj"]
+
+        # `packed_modules_mapping` needs to be modified before
+        # initializing AXK1Model, as it is passed inplace to
+        # quantization config init and may be used to select the
+        # quant_method for relevant layers during initialization.
+        self.fuse_qkv_a_proj = config.q_lora_rank is not None
+        if self.fuse_qkv_a_proj:
+            self.packed_modules_mapping["fused_qkv_a_proj"] = [
+                "q_a_proj",
+                "kv_a_proj_with_mqa",
+            ]
+
+        self.model = self.model_cls(
+            vllm_config=vllm_config, prefix=maybe_prefix(prefix, "model")
+        )
+        if get_pp_group().is_last_rank:
+            self.lm_head = ParallelLMHead(
+                config.vocab_size,
+                config.hidden_size,
+                quant_config=quant_config,
+                prefix=maybe_prefix(prefix, "lm_head"),
+            )
+        else:
+            self.lm_head = PPMissingLayer()
+        self.logits_processor = LogitsProcessor(config.vocab_size)
+        self.make_empty_intermediate_tensors = (
+            self.model.make_empty_intermediate_tensors
+        )
+        # Set MoE hyperparameters
+        self.num_moe_layers = (
+            self.config.num_hidden_layers - self.config.first_k_dense_replace
+        )
+        self.set_moe_parameters()
+
+    def set_moe_parameters(self):
+        self.expert_weights = []
+
+        self.num_expert_groups = getattr(self.config, "n_group", 1)
+
+        self.moe_layers = []
+        self.moe_mlp_layers = []
+        example_moe = None
+        for layer in self.model.layers:
+            if isinstance(layer, PPMissingLayer):
+                continue
+
+            assert isinstance(layer, AXK1DecoderLayer)
+            if isinstance(layer.mlp, AXK1MoE):
+                # Pick last one layer since the first ones may be dense layers.
+                example_moe = layer.mlp
+                self.moe_mlp_layers.append(layer.mlp)
+                self.moe_layers.append(layer.mlp.experts)
+
+        self.extract_moe_parameters(example_moe)
+
+    def embed_input_ids(self, input_ids: torch.Tensor) -> torch.Tensor:
+        return self.model.embed_input_ids(input_ids)
+
+    def forward(
+        self,
+        input_ids: torch.Tensor | None,
+        positions: torch.Tensor,
+        intermediate_tensors: IntermediateTensors | None = None,
+        inputs_embeds: torch.Tensor | None = None,
+    ) -> torch.Tensor | IntermediateTensors:
+        hidden_states = self.model(
+            input_ids, positions, intermediate_tensors, inputs_embeds
+        )
+        return hidden_states
+
+    def compute_logits(
+        self,
+        hidden_states: torch.Tensor,
+    ) -> torch.Tensor | None:
+        logits = self.logits_processor(self.lm_head, hidden_states)
+        return logits
+
+    def get_expert_mapping(self) -> list[tuple[str, str, int, str]]:
+        # Params for weights, fp8 weight scales, fp8 activation scales
+        # (param_name, weight_name, expert_id, shard_id)
+        return SharedFusedMoE.make_expert_params_mapping(
+            self,
+            ckpt_gate_proj_name="gate_proj",
+            ckpt_down_proj_name="down_proj",
+            ckpt_up_proj_name="up_proj",
+            num_experts=self.config.n_routed_experts,
+            num_redundant_experts=0,
+        )
+
+    def load_weights(self, weights: Iterable[tuple[str, torch.Tensor]]) -> set[str]:
+        rocm_aiter_moe_shared_expert_enabled = (
+            rocm_aiter_ops.is_fusion_moe_shared_experts_enabled()
+        )
+        stacked_params_mapping = [
+            # (param_name, shard_name, shard_id)
+            ("gate_up_proj", "gate_proj", 0),
+            ("gate_up_proj", "up_proj", 1),
+        ]
+        mla_params_mapping = [
+            ("fused_qkv_a_proj", "q_a_proj", 0),
+            ("fused_qkv_a_proj", "kv_a_proj_with_mqa", 1),
+        ]
+        mha_params_mapping = [
+            ("qkv_proj", "q_proj", "q"),
+            ("qkv_proj", "k_proj", "k"),
+            ("qkv_proj", "v_proj", "v"),
+        ]
+        if self.use_mha:
+            stacked_params_mapping.extend(mha_params_mapping)
+        else:
+            stacked_params_mapping.extend(mla_params_mapping)
+
+        # Params for weights, fp8 weight scales, fp8 activation scales
+        # (param_name, weight_name, expert_id, shard_id)
+        expert_params_mapping = SharedFusedMoE.make_expert_params_mapping(
+            self,
+            ckpt_gate_proj_name="gate_proj",
+            ckpt_down_proj_name="down_proj",
+            ckpt_up_proj_name="up_proj",
+            num_experts=self.config.n_routed_experts
+            + (
+                self.config.n_shared_experts
+                if rocm_aiter_moe_shared_expert_enabled
+                else 0
+            ),
+            num_redundant_experts=self.num_redundant_experts,
+        )
+
+        params_dict = dict(self.named_parameters())
+        loaded_params: set[str] = set()
+        for name, loaded_weight in weights:
+            if "rotary_emb.inv_freq" in name:
+                continue
+
+            spec_layer = get_spec_layer_idx_from_weight_name(self.config, name)
+            if spec_layer is not None:
+                continue  # skip spec decode layers for main model
+
+            is_fusion_moe_shared_experts_layer = (
+                rocm_aiter_moe_shared_expert_enabled and ("mlp.shared_experts" in name)
+            )
+
+            for param_name, weight_name, shard_id in stacked_params_mapping:
+                # Skip non-stacked layers and experts (experts handled below).
+                if weight_name not in name:
+                    continue
+                # We have mlp.experts[0].gate_proj in the checkpoint.
+                # Since we handle the experts below in expert_params_mapping,
+                # we need to skip here BEFORE we update the name, otherwise
+                # name will be updated to mlp.experts[0].gate_up_proj, which
+                # will then be updated below in expert_params_mapping
+                # for mlp.experts[0].gate_gate_up_proj, which breaks load.
+                if ("mlp.experts." in name) and name not in params_dict:
+                    continue
+                if is_fusion_moe_shared_experts_layer:
+                    continue
+                name_mapped = name.replace(weight_name, param_name)
+
+                # QKV fusion is optional, fall back to normal
+                # weight loading if it's not enabled
+                # if go with fusion option, then update name
+                if (
+                    param_name == "fused_qkv_a_proj"
+                ) and name_mapped not in params_dict:
+                    continue
+                else:
+                    name = name_mapped
+                # Skip loading extra bias for GPTQ models.
+                if name.endswith(".bias") and name not in params_dict:
+                    continue
+
+                if is_pp_missing_parameter(name, self):
+                    continue
+
+                param = params_dict[name]
+                weight_loader = param.weight_loader
+                weight_loader(param, loaded_weight, shard_id)
+                break
+            else:
+                is_expert_weight = False
+
+                # Special handling: when AITER fusion_shared_experts is enabled,
+                # checkpoints may provide a single widened shared_experts tensor
+                # without explicit expert indices
+                # (e.g. ...mlp.shared_experts.gate_proj.weight).
+                # For models with multiple shared experts, split that tensor
+                # evenly into per-shared-expert slices and load them into
+                # appended expert slots mlp.experts.{n_routed_experts + j}.*
+                # accordingly.
+                num_chunks = 1
+                if is_fusion_moe_shared_experts_layer:
+                    num_chunks = getattr(self.config, "n_shared_experts", 1) or 1
+                    # Determine split axis based on op type
+                    # gate/up: ColumnParallel → split along dim 0
+                    # down: RowParallel → split along dim 1
+                    split_dim = (
+                        1
+                        if ("down_proj.weight" in name and loaded_weight.ndim > 1)
+                        else 0
+                    )
+                    total = loaded_weight.shape[split_dim]
+                    assert total % num_chunks == 0, (
+                        f"Shared expert weight dim {total} "
+                        f"not divisible by num_chunks {num_chunks}"
+                    )
+                    chunk_size = total // num_chunks
+
+                for j in range(num_chunks):
+                    chunk_name = name
+                    weight_to_load = loaded_weight
+
+                    if is_fusion_moe_shared_experts_layer:
+                        chunk_slice = slice(j * chunk_size, (j + 1) * chunk_size)
+                        if loaded_weight.ndim == 1:
+                            weight_to_load = loaded_weight[chunk_slice]
+                        elif split_dim == 0:
+                            weight_to_load = loaded_weight[chunk_slice, :]
+                        else:
+                            weight_to_load = loaded_weight[:, chunk_slice]
+                        # Synthesize an expert-style name so expert mapping
+                        # can route it
+                        chunk_name = name.replace(
+                            "mlp.shared_experts",
+                            f"mlp.experts.{self.config.n_routed_experts + j}",
+                        )
+
+                    # Use expert_params_mapping to locate the destination
+                    # param and delegate to its expert-aware weight_loader
+                    # with expert_id.
+                    for mapping in expert_params_mapping:
+                        param_name, weight_name, expert_id, shard_id = mapping
+                        if weight_name not in chunk_name:
+                            continue
+
+                        # Anyway, this is an expert weight and should not be
+                        # attempted to load as other weights later
+                        is_expert_weight = True
+
+                        # Do not modify `name` since the loop may continue here
+                        # Instead, create a new variable
+                        name_mapped = chunk_name.replace(weight_name, param_name)
+
+                        if is_pp_missing_parameter(name_mapped, self):
+                            continue
+
+                        param = params_dict[name_mapped]
+                        # We should ask the weight loader to return success or
+                        # not here since otherwise we may skip experts with
+                        # other available replicas.
+                        weight_loader = typing.cast(
+                            Callable[..., bool], param.weight_loader
+                        )
+                        success = weight_loader(
+                            param,
+                            weight_to_load,
+                            name_mapped,
+                            shard_id=shard_id,
+                            expert_id=expert_id,
+                            return_success=True,
+                        )
+                        if success:
+                            if not is_fusion_moe_shared_experts_layer:
+                                name = name_mapped
+                            else:
+                                loaded_params.add(name_mapped)
+                            break
+                    else:
+                        if is_expert_weight:
+                            # We've checked that this is an expert weight
+                            # However it's not mapped locally to this rank
+                            # So we simply skip it
+                            continue
+
+                        # Skip loading extra bias for GPTQ models.
+                        if name.endswith(".bias") and name not in params_dict:
+                            continue
+
+                        # Remapping the name of FP8 kv-scale.
+                        name = maybe_remap_kv_scale_name(name, params_dict)
+                        if name is None:
+                            continue
+
+                        if is_pp_missing_parameter(name, self):
+                            continue
+
+                        param = params_dict[name]
+                        weight_loader = getattr(
+                            param, "weight_loader", default_weight_loader
+                        )
+                        weight_loader(param, loaded_weight)
+            if not is_fusion_moe_shared_experts_layer:
+                loaded_params.add(name)
+
+        return loaded_params
+
+
+def get_spec_layer_idx_from_weight_name(
+    config: AXK1Config, weight_name: str
+) -> int | None:
+    if config.num_nextn_predict_layers and config.num_nextn_predict_layers > 0:
+        layer_idx = config.num_hidden_layers
+        for i in range(config.num_nextn_predict_layers):
+            if weight_name.startswith(f"model.layers.{layer_idx + i}."):
+                return layer_idx + i
+    return None

vllm/model_executor/models/registry.py

@@ -75,6 +75,7 @@ _TEXT_GENERATION_MODELS = {
     "AquilaForCausalLM": ("llama", "LlamaForCausalLM"),  # AquilaChat2
     "ArceeForCausalLM": ("arcee", "ArceeForCausalLM"),
     "ArcticForCausalLM": ("arctic", "ArcticForCausalLM"),
+    "AXK1ForCausalLM": ("AXK1", "AXK1ForCausalLM"),
     # baichuan-7b, upper case 'C' in the class name
     "BaiChuanForCausalLM": ("baichuan", "BaiChuanForCausalLM"),
     # baichuan-13b, lower case 'c' in the class name

vllm/transformers_utils/configs/AXK1.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+from typing import Any
+
+from transformers import PretrainedConfig
+
+
+class AXK1Config(PretrainedConfig):
+    r"""
+    This is the configuration class to store the configuration of a [`AXK1Model`].
+    It is used to instantiate an A.X model according to the specified arguments,
+    defining the model architecture. Instantiating a configuration with the defaults
+    will yield a similar configuration to that of the A.X K1.
+    Configuration objects inherit from [`PretrainedConfig`] and can be used to control
+    the model outputs. Read the documentation from [`PretrainedConfig`] for more
+    information.
+    Args:
+        vocab_size (`int`, *optional*, defaults to 163840):
+            Vocabulary size of the A.X K1 model. Defines the number of different
+            tokens that can be represented by the `inputs_ids` passed when calling
+            [`AXK1Model`]
+        hidden_size (`int`, *optional*, defaults to 7168):
+            Dimension of the hidden representations.
+        intermediate_size (`int`, *optional*, defaults to 18432):
+            Dimension of the MLP representations.
+        moe_intermediate_size (`int`, *optional*, defaults to 2048):
+            Dimension of the MoE representations.
+        num_hidden_layers (`int`, *optional*, defaults to 61):
+            Number of hidden layers in the Transformer decoder.
+        num_nextn_predict_layers (`int`, *optional*, defaults to 1):
+            Number of nextn predict layers in the AXK1 Model.
+        num_attention_heads (`int`, *optional*, defaults to 64):
+            Number of attention heads for each attention layer in the Transformer
+            decoder.
+        n_shared_experts (`int`, *optional*, defaults to 1):
+            Number of shared experts, None means dense model.
+        n_routed_experts (`int`, *optional*, defaults to 192):
+            Number of routed experts, None means dense model.
+        routed_scaling_factor (`float`, *optional*, defaults to 2.5):
+            Scaling factor or routed experts.
+        topk_method (`str`, *optional*, defaults to `noaux_tc`):
+            Topk method used in routed gate.
+        n_group (`int`, *optional*, defaults to 8):
+            Number of groups for routed experts.
+        topk_group (`int`, *optional*, defaults to 4):
+            Number of selected groups for each token(for each token, ensuring the
+            selected experts is only within `topk_group` groups).
+        num_experts_per_tok (`int`, *optional*, defaults to 8):
+            Number of selected experts, None means dense model.
+        moe_layer_freq (`int`, *optional*, defaults to 1):
+            The frequency of the MoE layer: one expert layer for every
+            `moe_layer_freq - 1` dense layers.
+        first_k_dense_replace (`int`, *optional*, defaults to 1):
+            Number of dense layers in shallow layers
+            (embed->dense->dense->...->dense->moe->moe...->lm_head).
+                      \--k dense layers--/
+        norm_topk_prob (`bool`, *optional*, defaults to True):
+            Whether to normalize the weights of the routed experts.
+        scoring_func (`str`, *optional*, defaults to 'sigmoid'):
+            Method of computing expert weights.
+        aux_loss_alpha (`float`, *optional*, defaults to 0.0001):
+            Auxiliary loss weight coefficient.
+        seq_aux = (`bool`, *optional*, defaults to True):
+            Whether to compute the auxiliary loss for each individual sample.
+        num_key_value_heads (`int`, *optional*):
+            This is the number of key_value heads that should be used to implement
+            Grouped Query Attention. If `num_key_value_heads=num_attention_heads`,
+            the model will use Multi Head Attention (MHA), if `num_key_value_heads=1
+            the model will use Multi Query Attention (MQA) otherwise GQA is used. When
+            converting a multi-head checkpoint to a GQA checkpoint, each group key and
+            value head should be constructed by meanpooling all the original heads
+            within that group. For more details checkout
+            [this paper](https://arxiv.org/pdf/2305.13245.pdf).
+            If it is not specified, will default to `num_attention_heads`.
+        hidden_act (`str` or `function`, *optional*, defaults to `"silu"`):
+            The non-linear activation function (function or string) in the decoder.
+        max_position_embeddings (`int`, *optional*, defaults to 131072):
+            The maximum sequence length that this model might ever be used with.
+        initializer_range (`float`, *optional*, defaults to 0.02):
+            The standard deviation of the truncated_normal_initializer for
+            initializing all weight matrices.
+        rms_norm_eps (`float`, *optional*, defaults to 1e-06):
+            The epsilon used by the rms normalization layers.
+        use_cache (`bool`, *optional*, defaults to `True`):
+            Whether or not the model should return the last key/values attentions
+            (not used by all models). Only relevant if `config.is_decoder=True`.
+        pad_token_id (`int`, *optional*):
+            Padding token id.
+        bos_token_id (`int`, *optional*, defaults to 163691):
+            Beginning of stream token id.
+        eos_token_id (`int`, *optional*, defaults to 163691):
+            End of stream token id.
+        pretraining_tp (`int`, *optional*, defaults to 1):
+            Experimental feature. Tensor parallelism rank used during pretraining.
+            Please refer to
+            [this document](https://huggingface.co/docs/transformers/parallelism)
+            to understand more about it. This value is necessary to ensure exact
+            reproducibility of the pretraining results. Please refer to
+            [this issue](https://github.com/pytorch/pytorch/issues/76232).
+        tie_word_embeddings (`bool`, *optional*, defaults to `False`):
+            Whether to tie weight embeddings
+        rope_theta (`float`, *optional*, defaults to 10000.0):
+            The base period of the RoPE embeddings.
+        rope_scaling (`Dict`, *optional*):
+            Dictionary containing the scaling configuration for the RoPE embeddings.
+            Currently supports two scaling strategies: linear and dynamic.
+            Their scaling factor must be a float greater than 1. The expected format
+            is  `{"type": strategy name, "factor": scaling factor}`. When using this
+            flag, don't update `max_position_embeddings` to the expected new maximum.
+        attention_bias (`bool`, defaults to `False`, *optional*, defaults to `False`):
+            Whether to use a bias in the query, key, value and output projection
+            layers during self-attention.
+        attention_dropout (`float`, *optional*, defaults to 0.0):
+            The dropout ratio for the attention probabilities.
+    """
+
+    model_type = "AXK1"
+    keys_to_ignore_at_inference = ["past_key_values"]
+
+    def __init__(
+        self,
+        vocab_size: int = 163840,
+        hidden_size: int = 7168,
+        intermediate_size: int = 18432,
+        moe_intermediate_size: int = 2048,
+        num_hidden_layers: int = 61,
+        num_nextn_predict_layers: int | None = 1,
+        num_attention_heads: int = 64,
+        num_key_value_heads: int = 64,
+        n_shared_experts: int | None = 1,
+        n_routed_experts: int | None = 192,
+        ep_size: int | None = 8,  ## Ignored - Expert parallel size
+        routed_scaling_factor: float | None = 2.5,
+        kv_lora_rank: int | None = 512,
+        q_lora_rank: int | None = 1536,
+        qk_rope_head_dim: int | None = 64,
+        v_head_dim: int | None = 128,
+        qk_nope_head_dim: int | None = 128,
+        topk_method: str | None = "noaux_tc",
+        n_group: int | None = 8,
+        topk_group: int | None = 4,
+        num_experts_per_tok: int | None = 8,
+        moe_layer_freq: int | None = 1,
+        first_k_dense_replace: int = 1,
+        norm_topk_prob: bool = True,
+        scoring_func: str | None = "sigmoid",
+        aux_loss_alpha: float | None = 0.0001,
+        seq_aux: float | None = True,
+        hidden_act: str | None = "silu",
+        max_position_embeddings: int | None = 131072,
+        initializer_range: float | None = 0.02,
+        rms_norm_eps: float = 1e-6,
+        use_cache: bool | None = True,
+        pad_token_id: int | None = None,
+        bos_token_id: int | None = 163691,
+        eos_token_id: int | None = 163691,
+        pretraining_tp: int | None = 1,
+        tie_word_embeddings: bool | None = False,
+        rope_theta: float | None = 10000.0,
+        rope_scaling: dict[str, Any] | None = None,
+        rope_parameters: dict[str, Any] | None = None,
+        attention_bias: bool | None = False,
+        attention_dropout: float | None = 0.0,
+        **kwargs,
+    ):
+        self.vocab_size = vocab_size
+        self.max_position_embeddings = max_position_embeddings
+        self.hidden_size = hidden_size
+        self.intermediate_size = intermediate_size
+        self.moe_intermediate_size = moe_intermediate_size
+        self.num_hidden_layers = num_hidden_layers
+        self.num_nextn_predict_layers = num_nextn_predict_layers
+        self.num_attention_heads = num_attention_heads
+        self.n_shared_experts = n_shared_experts
+        self.n_routed_experts = n_routed_experts
+        self.ep_size = ep_size
+        self.routed_scaling_factor = routed_scaling_factor
+        self.kv_lora_rank = kv_lora_rank
+        self.q_lora_rank = q_lora_rank
+        self.qk_rope_head_dim = qk_rope_head_dim
+        self.v_head_dim = v_head_dim
+        self.qk_nope_head_dim = qk_nope_head_dim
+        self.topk_method = topk_method
+        self.n_group = n_group
+        self.topk_group = topk_group
+        self.num_experts_per_tok = num_experts_per_tok
+        self.moe_layer_freq = moe_layer_freq
+        self.first_k_dense_replace = first_k_dense_replace
+        self.norm_topk_prob = norm_topk_prob
+        self.scoring_func = scoring_func
+        self.aux_loss_alpha = aux_loss_alpha
+        self.seq_aux = seq_aux
+        # for backward compatibility
+        if num_key_value_heads is None:
+            num_key_value_heads = num_attention_heads
+
+        self.num_key_value_heads = num_key_value_heads
+        self.hidden_act = hidden_act
+        self.initializer_range = initializer_range
+        self.rms_norm_eps = rms_norm_eps
+        self.pretraining_tp = pretraining_tp
+        self.use_cache = use_cache
+        self.rope_theta = rope_theta
+        self.rope_scaling = rope_scaling
+        self.rope_parameters = rope_parameters
+        self.attention_bias = attention_bias
+        self.attention_dropout = attention_dropout
+
+        super().__init__(
+            pad_token_id=pad_token_id,
+            bos_token_id=bos_token_id,
+            eos_token_id=eos_token_id,
+            tie_word_embeddings=tie_word_embeddings,
+            **kwargs,
+        )

vllm/transformers_utils/configs/__init__.py

@@ -16,6 +16,7 @@ import importlib
 
 _CLASS_TO_MODULE: dict[str, str] = {
     "AfmoeConfig": "vllm.transformers_utils.configs.afmoe",
+    "AXK1Config": "vllm.transformers_utils.configs.AXK1",
     "BagelConfig": "vllm.transformers_utils.configs.bagel",
     "ChatGLMConfig": "vllm.transformers_utils.configs.chatglm",
     "ColModernVBertConfig": "vllm.transformers_utils.configs.colmodernvbert",
@@ -70,6 +71,7 @@ _CLASS_TO_MODULE: dict[str, str] = {
 
 __all__ = [
     "AfmoeConfig",
+    "AXK1Config",
     "BagelConfig",
     "ChatGLMConfig",
     "ColModernVBertConfig",

vllm/transformers_utils/model_arch_config_convertor.py

@@ -233,6 +233,7 @@ class ModelArchConfigConvertorBase:
         if not hasattr(self.hf_text_config, "model_type"):
             return False
         elif self.hf_text_config.model_type in (
+            "AXK1",
             "deepseek_v2",
             "deepseek_v3",
             "deepseek_v32",
@@ -253,7 +254,13 @@ class ModelArchConfigConvertorBase:
             # underlying architecture
             return (
                 self.hf_text_config.model.model_type
-                in ("deepseek_v2", "deepseek_v3", "deepseek_v32", "deepseek_mtp")
+                in (
+                    "AXK1",
+                    "deepseek_v2",
+                    "deepseek_v3",
+                    "deepseek_v32",
+                    "deepseek_mtp",
+                )
                 and self.hf_text_config.kv_lora_rank is not None
             )
         return False