[ROCm] Add AMD GPU support on Deepseek v3.2 and SparseMLA (#26670)

Signed-off-by: ganyi <ygan@amd.com>

csrc/cache_kernels.cu

@@ -552,7 +552,11 @@ __global__ void indexer_k_quant_and_cache_kernel(
 #ifndef USE_ROCM
   __syncwarp();
 #endif
+#if defined(__gfx942__)
+  float scale = fmaxf(amax, 1e-4) / 224.0f;
+#else
   float scale = fmaxf(amax, 1e-4) / 448.0f;
+#endif
   if (use_ue8m0) {
     scale = exp2f(ceilf(log2f(scale)));
   }

vllm/attention/ops/rocm_aiter_mla_sparse.py

@@ -0,0 +1,210 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+import importlib
+from functools import lru_cache
+
+import torch
+
+from vllm._aiter_ops import rocm_aiter_ops
+from vllm.logger import init_logger
+from vllm.platforms import current_platform
+
+logger = init_logger(__name__)
+
+
+# Take from https://github.com/deepseek-ai/DeepGEMM/blob/main/tests/test_attention.py#L84
+def fp8_mqa_logits_torch(
+    q: torch.Tensor,
+    kv: tuple[torch.Tensor, torch.Tensor],
+    weights: torch.Tensor,
+    cu_seqlen_ks: torch.Tensor,
+    cu_seqlen_ke: torch.Tensor,
+) -> torch.Tensor:
+    """Compute FP8 MQA logits for a single sequence without KV paging.
+
+    Args:
+        q: Query tensor of shape [M, H, D]. Casted to
+            `torch.float8_e4m3fn` by caller.
+        kv: Tuple `(k_fp8, k_scales)` where `k_fp8` has shape [N, D] with
+            dtype `torch.float8_e4m3fn` and `k_scales` has shape [N] (or
+            [N, 1]) with dtype `torch.float32`.
+        weights: weights of shape [M, H], dtype `torch.float32`.
+        cu_seqlen_ks: Start indices (inclusive) for valid K per query position,
+            shape [M], dtype int32.
+        cu_seqlen_ke: End indices (exclusive) for valid K per query position,
+            shape [M], dtype int32.
+
+    Returns:
+        Logits tensor of shape [M, N], dtype `torch.float32`.
+    """
+    kv, scale = kv
+    seq_len_kv = kv.shape[0]
+    k = kv.to(torch.bfloat16)
+    q = q.to(torch.bfloat16)
+
+    mask_lo = (
+        torch.arange(0, seq_len_kv, device="cuda")[None, :] >= cu_seqlen_ks[:, None]
+    )
+    mask_hi = (
+        torch.arange(0, seq_len_kv, device="cuda")[None, :] < cu_seqlen_ke[:, None]
+    )
+    mask = mask_lo & mask_hi
+
+    score = torch.einsum("mhd,nd->hmn", q, k).float() * scale
+    logits = (score.relu() * weights.unsqueeze(-1).transpose(0, 1)).sum(dim=0)
+    logits = logits.masked_fill(~mask, float("-inf"))
+
+    return logits
+
+
+def rocm_fp8_mqa_logits(
+    q: torch.Tensor,
+    kv: tuple[torch.Tensor, torch.Tensor],
+    weights: torch.Tensor,
+    cu_seqlen_ks: torch.Tensor,
+    cu_seqlen_ke: torch.Tensor,
+) -> torch.Tensor:
+    """Compute FP8 MQA logits for a single sequence without KV paging.
+
+    Args:
+        q: Query tensor of shape [M, H, D]. Casted to
+            `torch.float8_e4m3fn` by caller.
+        kv: Tuple `(k_fp8, k_scales)` where `k_fp8` has shape [N, D] with
+            dtype `torch.float8_e4m3fn` and `k_scales` has shape [N] (or
+            [N, 1]) with dtype `torch.float32`.
+        weights: weights of shape [M, H], dtype `torch.float32`.
+        cu_seqlen_ks: Start indices (inclusive) for valid K per query position,
+            shape [M], dtype int32.
+        cu_seqlen_ke: End indices (exclusive) for valid K per query position,
+            shape [M], dtype int32.
+
+    Returns:
+        Logits tensor of shape [M, N], dtype `torch.float32`.
+    """
+
+    # TODO(ganyi): Temporarily workaround, will remove the module check and reference
+    # path after aiter merge this kernel into main
+    @lru_cache
+    def has_mqa_logits_module():
+        return importlib.util.find_spec("aiter.ops.triton.fp8_mqa_logits") is not None
+
+    if rocm_aiter_ops.is_enabled() and has_mqa_logits_module():
+        from aiter.ops.triton.fp8_mqa_logits import fp8_mqa_logits
+
+        kv, scale = kv
+        return fp8_mqa_logits(q, kv, scale, weights, cu_seqlen_ks, cu_seqlen_ke)
+    else:
+        return fp8_mqa_logits_torch(q, kv, weights, cu_seqlen_ks, cu_seqlen_ke)
+
+
+# Taken from https://github.com/deepseek-ai/DeepGEMM/blob/main/tests/test_attention.py#L156
+def fp8_paged_mqa_logits_torch(
+    q: torch.Tensor,
+    kv_cache: torch.Tensor,
+    weights: torch.Tensor,
+    context_lens: torch.Tensor,
+    block_tables: torch.Tensor,
+    max_model_len: int,
+):
+    from vllm.utils.math_utils import cdiv
+
+    fp8_dtype = current_platform.fp8_dtype()
+    batch_size, next_n, _, dim = q.size()
+    kv_cache, scale = kv_cache[..., :dim], kv_cache[..., dim:]
+    scale = scale.contiguous().view(torch.float)
+    q = q.float()
+    kv_cache = kv_cache.view(fp8_dtype).float() * scale
+    num_block, block_size, _, dim = kv_cache.size()
+    logits = torch.full(
+        [batch_size * next_n, max_model_len],
+        float("-inf"),
+        device=q.device,
+        dtype=torch.float32,
+    )
+    context_lens = context_lens.tolist()
+    for i in range(batch_size):
+        context_len = context_lens[i]
+        q_offsets = torch.arange(context_len - next_n, context_len, device="cuda")
+        weight_slice = (
+            weights[i * next_n : (i + 1) * next_n, :].transpose(0, 1).contiguous()
+        )
+        for block_rk in range(cdiv(context_len, block_size)):
+            block_idx = block_tables[i][block_rk]
+            qx, kx = q[i], kv_cache[block_idx]
+            k_offsets = torch.arange(
+                block_rk * block_size, (block_rk + 1) * block_size, device="cuda"
+            )
+            mask = (k_offsets[None, :] < context_len) & (
+                k_offsets[None, :] <= q_offsets[:, None]
+            )
+            s = torch.where(
+                mask[None, :, :],
+                (qx.transpose(0, 1) @ kx.transpose(0, 1).transpose(1, 2)).to(
+                    logits.dtype
+                ),
+                float("-inf"),
+            )
+            s = torch.relu(s) * weight_slice[..., None]
+            s = s.sum(dim=0)
+            logits[
+                i * next_n : (i + 1) * next_n,
+                block_rk * block_size : (block_rk + 1) * block_size,
+            ] = torch.where(k_offsets[None, :] <= q_offsets[:, None], s, float("-inf"))
+    return logits
+
+
+def rocm_fp8_paged_mqa_logits(
+    q_fp8: torch.Tensor,
+    kv_cache_fp8: torch.Tensor,
+    weights: torch.Tensor,
+    context_lens: torch.Tensor,
+    block_tables: torch.Tensor,
+    schedule_metadata: torch.Tensor,
+    max_model_len: int,
+) -> torch.Tensor:
+    """Compute FP8 MQA logits using paged KV-cache.
+
+    Args:
+        q_fp8: Query tensor of shape [B, next_n, H, D]. Casted to
+            `torch.float8_e4m3fn` by caller.
+        kv_cache_fp8: Paged KV-cache in packed FP8+scale layout with shape
+            [num_blocks, block_size, 1, D+4], dtype `torch.uint8`. The last
+            4 bytes per (block,pos) store the `float` dequant scale.
+        weights: Tensor of shape [B * next_n, H], dtype `torch.float32`.
+        context_lens: Tensor of shape [B], dtype int32; effective context length
+            for each batch element.
+        block_tables: Tensor of shape [B, max_blocks], dtype int32; maps logical
+            block indices to physical blocks in the paged cache.
+        schedule_metadata: Returned by `get_paged_mqa_logits_metadata`;
+            used to distribute work across SMs.
+        max_model_len: Maximum sequence length used to size the logits output.
+
+    Returns:
+        Logits tensor of shape [B * next_n, max_model_len], dtype
+        `torch.float32`.
+    """
+
+    if rocm_aiter_ops.is_enabled():
+        from aiter.ops.triton.pa_mqa_logits import deepgemm_fp8_paged_mqa_logits_stage1
+
+        batch_size, next_n, heads, _ = q_fp8.shape
+        out_qk = torch.full(
+            (heads, batch_size * next_n, max_model_len),
+            float("-inf"),
+            device="cuda",
+            dtype=torch.float32,
+        )
+        deepgemm_fp8_paged_mqa_logits_stage1(
+            q_fp8,
+            kv_cache_fp8,
+            weights,
+            out_qk,
+            context_lens,
+            block_tables,
+            max_model_len,
+        )
+        return out_qk.sum(dim=0)
+    else:
+        return fp8_paged_mqa_logits_torch(
+            q_fp8, kv_cache_fp8, weights, context_lens, block_tables, max_model_len
+        )

vllm/model_executor/models/deepseek_v2.py

@@ -594,6 +594,7 @@ def sparse_attn_indexer(
 ) -> torch.Tensor:
     # careful! this will be None in dummy run
     attn_metadata = get_forward_context().attn_metadata
+    fp8_dtype = current_platform.fp8_dtype()
     # assert isinstance(attn_metadata, dict)
     if not isinstance(attn_metadata, dict):
         return sparse_attn_indexer_fake(
@@ -633,7 +634,7 @@ def sparse_attn_indexer(
             k_fp8 = torch.empty(
                 [chunk.total_seq_lens, head_dim],
                 device=k.device,
-                dtype=torch.float8_e4m3fn,
+                dtype=fp8_dtype,
             )
             k_scale = torch.empty(
                 [chunk.total_seq_lens, 4],
@@ -647,7 +648,12 @@ def sparse_attn_indexer(
                 chunk.block_table,
                 chunk.cu_seq_lens,
             )
-            logits = fp8_mqa_logits(
+            fp8_mqa_logits_func = fp8_mqa_logits
+            if current_platform.is_rocm():
+                from vllm.attention.ops.rocm_aiter_mla_sparse import rocm_fp8_mqa_logits
+
+                fp8_mqa_logits_func = rocm_fp8_mqa_logits
+            logits = fp8_mqa_logits_func(
                 q_fp8[chunk.token_start : chunk.token_end],
                 (k_fp8, k_scale.view(torch.float32)),
                 weights[chunk.token_start : chunk.token_end],
@@ -692,7 +698,14 @@ def sparse_attn_indexer(
         next_n = padded_q_fp8_decode_tokens.shape[1]
         assert batch_size == decode_metadata.seq_lens.shape[0]
         num_padded_tokens = batch_size * next_n
-        logits = fp8_paged_mqa_logits(
+        fp8_paged_mqa_logits_func = fp8_paged_mqa_logits
+        if current_platform.is_rocm():
+            from vllm.attention.ops.rocm_aiter_mla_sparse import (
+                rocm_fp8_paged_mqa_logits,
+            )
+
+            fp8_paged_mqa_logits_func = rocm_fp8_paged_mqa_logits
+        logits = fp8_paged_mqa_logits_func(
             padded_q_fp8_decode_tokens,
             kv_cache,
             weights[:num_padded_tokens],
@@ -749,7 +762,8 @@ def sparse_attn_indexer_fake(
     _flattened_kv = torch.empty(
         [total_seq_lens, head_dim + 4], device=k.device, dtype=torch.uint8
     )
-    _k_fp8 = _flattened_kv[..., :head_dim].view(torch.float8_e4m3fn).contiguous()
+    fp8_dtype = current_platform.fp8_dtype()
+    _k_fp8 = _flattened_kv[..., :head_dim].view(fp8_dtype).contiguous()
     _k_scale = _flattened_kv[..., head_dim:].view(torch.float32).contiguous()
     return topk_indices_buffer
 

vllm/platforms/rocm.py

@@ -225,7 +225,18 @@ class RocmPlatform(Platform):
         from vllm.attention.backends.registry import AttentionBackendEnum
 
         if use_sparse:
-            raise NotImplementedError("Sparse Attention is not supported on ROCm.")
+            if kv_cache_dtype.startswith("fp8"):
+                raise ValueError(
+                    "ROCMAiterMLASparseBackend doesn't support fp8 kv_cache_dtype."
+                )
+            assert block_size == 1, (
+                "Sparse MLA backend on ROCm only supports block size 1 for now."
+            )
+            logger.info_once("Using Sparse MLA backend on V1 engine.")
+            return (
+                "vllm.v1.attention.backends.mla.rocm_aiter_mla_sparse."
+                "ROCMAiterMLASparseBackend"
+            )
 
         if use_mla:
             if selected_backend is None:

vllm/utils/deep_gemm.py

@@ -325,6 +325,7 @@ DEFAULT_BLOCK_SIZE = [128, 128]
 def per_block_cast_to_fp8(
     x: torch.Tensor, block_size: list[int] = DEFAULT_BLOCK_SIZE, use_ue8m0: bool = False
 ) -> tuple[torch.Tensor, torch.Tensor]:
+    fp8_dtype = current_platform.fp8_dtype()
     assert x.dim() == 2
     m, n = x.shape
     block_m, block_n = block_size
@@ -334,9 +335,9 @@ def per_block_cast_to_fp8(
     x_padded[:m, :n] = x
     x_view = x_padded.view(-1, block_m, x_padded.size(1) // block_n, block_n)
     x_amax = x_view.abs().float().amax(dim=(1, 3), keepdim=True).clamp(1e-4)
-    sf = x_amax / 448.0
+    sf = x_amax / 224.0 if current_platform.is_fp8_fnuz() else x_amax / 448.0
     sf = _ceil_to_ue8m0(sf) if use_ue8m0 else sf
-    x_scaled = (x_view * (1.0 / sf)).to(torch.float8_e4m3fn)
+    x_scaled = (x_view * (1.0 / sf)).to(fp8_dtype)
     return x_scaled.view_as(x_padded)[:m, :n].contiguous(), sf.view(
         x_view.size(0), x_view.size(2)
     )

vllm/v1/attention/backends/mla/flashmla_sparse.py

@@ -168,7 +168,7 @@ def _convert_req_index_to_global_index_kernel(
     inblock_off = tok % BLOCK_SIZE
 
     # Guard block_table access
-    valid_block = block_id < max_num_blocks_per_req
+    valid_block = (block_id < max_num_blocks_per_req) & (block_id >= 0)
     bt_ptr = block_table_ptr + req * bt_stride0 + block_id * bt_stride1
     base = tl.load(bt_ptr, mask=valid_block, other=0)
 

vllm/v1/attention/backends/mla/indexer.py

@@ -11,7 +11,8 @@ from vllm.attention.backends.abstract import (
 )
 from vllm.config import VllmConfig
 from vllm.logger import init_logger
-from vllm.utils.deep_gemm import get_paged_mqa_logits_metadata
+from vllm.platforms import current_platform
+from vllm.utils.deep_gemm import get_paged_mqa_logits_metadata, is_deep_gemm_supported
 from vllm.v1.attention.backends.utils import (
     AttentionCGSupport,
     AttentionMetadataBuilder,
@@ -23,7 +24,9 @@ logger = init_logger(__name__)
 
 
 class DeepseekV32IndexerBackend(AttentionBackend):
-    supported_kernel_block_sizes: ClassVar[list[int | MultipleOf]] = [64]
+    supported_kernel_block_sizes: ClassVar[list[int | MultipleOf]] = [
+        1 if current_platform.is_rocm() else 64
+    ]
 
     @classmethod
     def get_supported_head_sizes(cls) -> list[int]:
@@ -328,10 +331,10 @@ class DeepseekV32IndexerMetadataBuilder(AttentionMetadataBuilder):
             requires_padding = (decode_lens_cpu.max() > decode_lens_cpu.min()).item()
 
             seq_lens = common_attn_metadata.seq_lens[:num_decodes]
-
-            self.scheduler_metadata_buffer[:] = get_paged_mqa_logits_metadata(
-                seq_lens, self.kv_cache_spec.block_size, self.num_sms
-            )
+            if is_deep_gemm_supported():
+                self.scheduler_metadata_buffer[:] = get_paged_mqa_logits_metadata(
+                    seq_lens, self.kv_cache_spec.block_size, self.num_sms
+                )
             decode_metadata = DeepSeekV32IndexerDecodeMetadata(
                 block_table=common_attn_metadata.block_table_tensor[:num_decodes, ...],
                 seq_lens=common_attn_metadata.seq_lens[:num_decodes],

vllm/v1/attention/backends/mla/rocm_aiter_mla_sparse.py

@@ -0,0 +1,325 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+from dataclasses import dataclass
+from typing import TYPE_CHECKING, ClassVar, Optional
+
+import numpy as np
+import torch
+
+from vllm import _custom_ops as ops
+from vllm._aiter_ops import rocm_aiter_ops
+from vllm.attention.backends.abstract import (
+    AttentionBackend,
+    AttentionLayer,
+    AttentionMetadata,
+)
+from vllm.attention.backends.utils import get_mla_dims
+from vllm.config import VllmConfig
+from vllm.logger import init_logger
+from vllm.v1.attention.backends.mla.common import (
+    MLACommonBaseImpl,
+)
+from vllm.v1.attention.backends.mla.flashmla_sparse import (
+    triton_convert_req_index_to_global_index,
+)
+from vllm.v1.attention.backends.utils import (
+    AttentionCGSupport,
+    AttentionMetadataBuilder,
+    CommonAttentionMetadata,
+)
+from vllm.v1.kv_cache_interface import AttentionSpec
+
+if TYPE_CHECKING:
+    from vllm.model_executor.models.deepseek_v2 import Indexer
+logger = init_logger(__name__)
+
+
+class ROCMAiterMLASparseBackend(AttentionBackend):
+    accept_output_buffer: bool = True
+
+    @staticmethod
+    def get_name() -> str:
+        return "ROCM_AITER_MLA_SPARSE"
+
+    @staticmethod
+    def get_metadata_cls() -> type[AttentionMetadata]:
+        return ROCMAiterMLASparseMetadata
+
+    @staticmethod
+    def get_builder_cls() -> type["ROCMAiterMLASparseMetadataBuilder"]:
+        return ROCMAiterMLASparseMetadataBuilder
+
+    @staticmethod
+    def get_impl_cls() -> type["ROCMAiterMLASparseImpl"]:
+        return ROCMAiterMLASparseImpl
+
+    @staticmethod
+    def get_kv_cache_shape(
+        num_blocks: int,
+        block_size: int,
+        num_kv_heads: int,  # assumed to be 1 for MLA
+        head_size: int,
+        cache_dtype_str: str = "auto",
+    ) -> tuple[int, ...]:
+        return (num_blocks, block_size, head_size)
+
+    @classmethod
+    def get_supported_dtypes(cls) -> list[torch.dtype]:
+        return [torch.bfloat16]
+
+    @classmethod
+    def get_supported_head_sizes(cls) -> list[int]:
+        return [576]
+
+
+@dataclass
+class ROCMAiterMLASparseMetadata:
+    num_reqs: int
+    max_query_len: int
+    max_seq_len: int
+
+    num_actual_tokens: int  # Number of tokens excluding padding.
+    query_start_loc: torch.Tensor
+    slot_mapping: torch.Tensor
+
+    block_table: torch.Tensor
+    req_id_per_token: torch.Tensor
+    block_size: int = 1
+    topk_tokens: int = 2048
+
+
+@dataclass
+class ROCMAiterMLASparseMetadataBuilder(
+    AttentionMetadataBuilder[ROCMAiterMLASparseMetadata]
+):
+    cudagraph_support: ClassVar[AttentionCGSupport] = AttentionCGSupport.NEVER
+
+    def __init__(
+        self,
+        kv_cache_spec: AttentionSpec,
+        layer_names: list[str],
+        vllm_config: VllmConfig,
+        device: torch.device,
+    ):
+        self.kv_cache_spec = kv_cache_spec
+        self.model_config = vllm_config.model_config
+        parallel_config = vllm_config.parallel_config
+        self.device = device
+
+        self.num_heads = self.model_config.get_num_attention_heads(parallel_config)
+        self.mla_dims = get_mla_dims(self.model_config)
+        self.topk_tokens = vllm_config.model_config.hf_config.index_topk
+        self.topk_tokens_tensor = torch.tensor(
+            [self.topk_tokens], device=device, dtype=torch.int32
+        )
+        self.max_model_len_tensor = torch.tensor(
+            [self.model_config.max_model_len], device=device, dtype=torch.int32
+        )
+        # this is ignored by `flash_mla_with_kvcache` if indices not None
+        self.dummy_block_table = torch.empty(
+            (1, 1), dtype=torch.int32, device=self.device
+        )
+
+        self.req_id_per_token_buffer = torch.empty(
+            (vllm_config.scheduler_config.max_num_batched_tokens,),
+            dtype=torch.int32,
+            device=device,
+        )
+
+    def build(
+        self,
+        common_prefix_len: int,
+        common_attn_metadata: CommonAttentionMetadata,
+        fast_build: bool = False,
+    ) -> ROCMAiterMLASparseMetadata:
+        num_tokens = common_attn_metadata.num_actual_tokens
+        starts = np.asarray(common_attn_metadata.query_start_loc_cpu, dtype=np.int32)
+        seg_lengths = np.diff(starts)
+        req_id_per_token = np.repeat(
+            np.arange(seg_lengths.shape[0], dtype=np.int32), seg_lengths
+        )
+        # Zero-fill for cudagraphs
+        self.req_id_per_token_buffer.fill_(0)
+        self.req_id_per_token_buffer[: req_id_per_token.shape[0]].copy_(
+            torch.from_numpy(req_id_per_token), non_blocking=True
+        )
+        req_id_per_token = self.req_id_per_token_buffer[:num_tokens]
+
+        metadata = ROCMAiterMLASparseMetadata(
+            num_reqs=common_attn_metadata.num_reqs,
+            max_query_len=common_attn_metadata.max_query_len,
+            max_seq_len=common_attn_metadata.max_seq_len,
+            num_actual_tokens=common_attn_metadata.num_actual_tokens,
+            query_start_loc=common_attn_metadata.query_start_loc,
+            slot_mapping=common_attn_metadata.slot_mapping,
+            block_table=common_attn_metadata.block_table_tensor,
+            req_id_per_token=req_id_per_token,
+            block_size=self.kv_cache_spec.block_size,
+            topk_tokens=self.topk_tokens,
+        )
+        return metadata
+
+
+# Take from
+# https://github.com/deepseek-ai/FlashMLA/blob/main/tests/test_flash_mla_prefill.py#L72
+def reference_mla_sparse_prefill(
+    q: torch.Tensor, kv: torch.Tensor, indices: torch.Tensor, sm_scale: float, d_v: int
+) -> tuple[torch.Tensor, torch.Tensor]:
+    import math
+
+    def log2sumexp2(a: torch.Tensor, dim: int) -> torch.Tensor:
+        return torch.logsumexp(a * math.log(2), dim=dim) * math.log2(math.e)
+
+    skv = kv.shape[0]
+    sq = q.shape[0]
+    topk = indices.shape[-1]
+    dqk = q.shape[-1]
+    indices = indices[:, 0, :]  # [s_q, topk]
+    invalid_indices_mask = (indices < 0) | (indices >= skv)
+    indices[invalid_indices_mask] = 0
+    qs = q  # [s_q, h_q, d_qk]
+    kvs = kv[:, 0, :][indices].view(sq, topk, dqk)  # [s_q, topk, d_qk]
+
+    attn_score = (qs @ kvs.transpose(1, 2)).float()  # [s_q, h_q, topk]
+    attn_score.masked_fill_(invalid_indices_mask.unsqueeze(1), float("-inf"))
+    attn_score *= sm_scale * math.log2(math.e)
+    lse = log2sumexp2(attn_score, dim=-1)  # [s_q, h_q]
+    attn_score = torch.exp2(attn_score - lse.unsqueeze(-1))  # [s_q, h_q, topk]
+    result = attn_score.to(q.dtype) @ kvs[:, :, :d_v]
+    return (result, lse)
+
+
+class ROCMAiterMLASparseImpl(MLACommonBaseImpl[ROCMAiterMLASparseMetadata]):
+    def __init__(
+        self,
+        num_heads: int,
+        head_size: int,
+        scale: float,
+        num_kv_heads: int,
+        alibi_slopes: list[float] | None,
+        sliding_window: int | None,
+        kv_cache_dtype: str,
+        logits_soft_cap: float | None,
+        attn_type: str,
+        kv_sharing_target_layer_name: str | None,
+        # MLA Specific Arguments
+        topk_indice_buffer: torch.Tensor | None = None,
+        indexer: Optional["Indexer"] = None,
+        **mla_args,
+    ) -> None:
+        super().__init__(
+            num_heads,
+            head_size,
+            scale,
+            num_kv_heads,
+            alibi_slopes,
+            sliding_window,
+            kv_cache_dtype,
+            logits_soft_cap,
+            attn_type,
+            kv_sharing_target_layer_name,
+            **mla_args,
+        )
+        self.softmax_scale = scale
+        assert indexer is not None
+        self.topk_indices_buffer = indexer.topk_indices_buffer
+        self.is_fp8bmm_enabled = rocm_aiter_ops.is_fp8bmm_enabled()
+
+    def _forward_bf16_kv(
+        self,
+        q: torch.Tensor,
+        kv_c_and_k_pe_cache: torch.Tensor,
+        topk_indices: torch.Tensor,
+        attn_metadata: ROCMAiterMLASparseMetadata,
+    ) -> torch.Tensor:
+        num_tokens = q.shape[0]
+        kv_c_and_k_pe_cache = kv_c_and_k_pe_cache.view(
+            -1, 1, kv_c_and_k_pe_cache.shape[-1]
+        )
+
+        topk_indices = topk_indices.view(num_tokens, 1, -1)
+        output = reference_mla_sparse_prefill(
+            q, kv_c_and_k_pe_cache, topk_indices, self.softmax_scale, 512
+        )[0]
+        return output[:, : self.num_heads, :]
+
+    def forward(
+        self,
+        layer: AttentionLayer,
+        q: torch.Tensor,
+        k_c_normed: torch.Tensor,  # key in unified attn
+        k_pe: torch.Tensor,  # value in unified attn
+        kv_cache: torch.Tensor,
+        attn_metadata: ROCMAiterMLASparseMetadata,
+        output: torch.Tensor | None = None,
+        output_scale: torch.Tensor | None = None,
+        output_block_scale: torch.Tensor | None = None,
+    ) -> torch.Tensor:
+        # NOTE(lucas): for the sparse FlashMLA kernels the kernels want to use
+        # MQA 576/512 approach for both prefill and decode
+
+        assert output is not None, "Output tensor must be provided."
+
+        if output_scale is not None or output_block_scale is not None:
+            raise NotImplementedError(
+                "fused output quantization is not yet supported for ROCMAiterMLASparse"
+            )
+
+        if attn_metadata is None:
+            # The zero fill is required when used with DP + EP
+            # to ensure all ranks within a DP group compute the
+            # same expert outputs.
+            return output.fill_(0)
+
+        num_actual_toks = attn_metadata.num_actual_tokens
+
+        # Inputs and outputs may be padded for CUDA graphs
+
+        q = q[:num_actual_toks, ...]
+        k_c_normed = k_c_normed[:num_actual_toks, ...]
+        k_pe = k_pe[:num_actual_toks, ...]
+
+        q_nope, q_pe = q.split([self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
+        # Convert from (B, N, P) to (N, B, P)
+        q_nope = q_nope.transpose(0, 1)
+        if self.is_fp8bmm_enabled:
+            # Multiply+Transpose (N, B, P)x(N, P, L)->(N, B, L)->(B, N, L)
+            ql_nope = rocm_aiter_ops.triton_fp8_bmm(
+                q_nope, self.W_K, self.W_K_scale, group_size=128, transpose_bm=True
+            )
+        else:
+            # Multiply (N, B, P) x (N, P, L) -> (N, B, L)
+            ql_nope = torch.bmm(q_nope, self.W_UK_T)
+            # Convert from (N, B, L) to (B, N, L)
+            ql_nope = ql_nope.transpose(0, 1)
+
+        topk_indices = self.topk_indices_buffer[:num_actual_toks]
+
+        topk_indices_global = triton_convert_req_index_to_global_index(
+            attn_metadata.req_id_per_token,
+            attn_metadata.block_table,
+            topk_indices,
+            BLOCK_SIZE=attn_metadata.block_size,
+            NUM_TOPK_TOKENS=attn_metadata.topk_tokens,
+        )
+
+        q = torch.cat([ql_nope, q_pe], dim=-1)
+
+        # write the latent and rope to kv cache
+        if kv_cache.numel() > 0:
+            ops.concat_and_cache_mla(
+                k_c_normed,
+                k_pe.squeeze(1),
+                kv_cache,
+                attn_metadata.slot_mapping.flatten(),
+                kv_cache_dtype=self.kv_cache_dtype,
+                scale=layer._k_scale,
+            )
+
+        attn_out = self._forward_bf16_kv(
+            q, kv_cache, topk_indices_global, attn_metadata
+        )
+
+        self._v_up_proj(attn_out, out=output[:num_actual_toks])
+        return output

vllm/v1/worker/utils.py

@@ -316,7 +316,7 @@ def bind_kv_cache(
             # TODO - analyze where runner_kv_caches is used and the right
             # way to ensure it properly reflects multiple attention layers
             # in the same decoder block.
-            if current_platform.is_cuda() or current_platform.is_xpu():
+            if current_platform.is_cuda_alike() or current_platform.is_xpu():
                 # We know that the GPU runner is not impacted by this
                 # case. Some test code depends on runner_kv_caches, but
                 # not in a way that's impacted by ignoring this.