@@ -0,0 +1 @@
+gfx,cu_num,M,N,K,libtype,kernelId,splitK,us,kernelName,tflops,bw,errRatio
@@ -0,0 +1 @@
+M,N,K
@@ -135,6 +135,13 @@ def mp_lock(
     f"{AITER_ROOT_DIR}/aiter/configs/a8w8_blockscale_tuned_gemm.csv",
 )
 
+# Native E8M0 group32 scales have a different operand contract from the
+# FP32 128x128 blockscale family, so shape-identical rows must stay separate.
+AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32 = os.getenv(
+    "AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32",
+    f"{AITER_ROOT_DIR}/aiter/configs/a8w8_blockscale_group32_tuned_gemm.csv",
+)
+
 AITER_CONFIG_FMOE = os.getenv(
     "AITER_CONFIG_FMOE",
     f"{AITER_ROOT_DIR}/aiter/configs/tuned_fmoe.csv",
@@ -286,6 +293,14 @@ def AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_FILE(self):
             "a8w8_blockscale_tuned_gemm",
         )
 
+    @property
+    def AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32_FILE(self):
+        return self.get_config_file(
+            "AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32",
+            AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32,
+            "a8w8_blockscale_group32_tuned_gemm",
+        )
+
     @property
     def AITER_CONFIG_FMOE_FILE(self):
         return self.get_config_file(
 
@@ -812,8 +812,28 @@ def _blockscale_triton(
     x_scale: Tensor,
     w_scale: Tensor,
     dtype: torch.dtype,
+    *,
+    group32: bool = False,
+    split_k: int | None = None,
 ) -> Tensor:
-    """Run the triton kernel on CK's inputs: row-major x_scale, (N, K) weight, JIT per arch."""
+    """Run Triton on unshuffled weights with the selected scale format."""
+    if group32:
+        from aiter.ops.triton.gemm.basic.gemm_a8w8_blockscale_group32 import (
+            gemm_a8w8_blockscale_group32,
+        )
+
+        assert WQ.ndim == w_scale.ndim == 2, "Expected matrix weights and scales"
+        group_n = 32 if w_scale.shape[0] == -(-WQ.shape[0] // 32) else 1
+        return gemm_a8w8_blockscale_group32(
+            XQ,
+            WQ,
+            x_scale,
+            w_scale,
+            dtype=dtype,
+            weight_group_rows=group_n,
+            split_k=split_k,
+        )
+
     from aiter.ops.triton.gemm.basic.gemm_a8w8_blockscale import (
         gemm_a8w8_blockscale as _gemm_a8w8_blockscale_triton,
     )
@@ -830,77 +850,123 @@ def gemm_a8w8_blockscale_fake(
     w_scale: Tensor,
     dtype: torch.dtype = dtypes.bf16,
     isBpreshuffled=False,
+    split_k: int | None = None,
 ) -> torch.Tensor:
     m = XQ.shape[0]
     n = WQ.shape[0]
     Y = torch.empty(m, n, dtype=dtype, device=XQ.device)
     return Y
 
 
-@torch_compile_guard(gen_fake=gemm_a8w8_blockscale_fake)
+@torch_compile_guard(mutates_args=[], gen_fake=gemm_a8w8_blockscale_fake)
 def gemm_a8w8_blockscale(
     XQ: Tensor,
     WQ: Tensor,
     x_scale: Tensor,
     w_scale: Tensor,
     dtype: torch.dtype = dtypes.bf16,
     isBpreshuffled: bool = False,
+    split_k: int | None = None,
 ) -> torch.Tensor:
-    assert dtype in [
-        dtypes.bf16,
-        dtypes.fp16,
-    ], f"Output {dtype=} is currently not supported in gemm_a8w8"
+    """Blockscaled A8W8 GEMM with configuration-first backend dispatch.
+
+    Native E8M0 group32 scales (typed tensors or uint8 views) use
+    AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32;
+    FP32 128x128 scales use AITER_CONFIG_GEMM_A8W8_BLOCKSCALE. Both tables are
+    queried through get_CKGEMM_config before choosing a fallback. Group32
+    currently supports libtype="triton", also its default on a config miss.
+    Triton tile and split-K parameters come from its own tuning tables.
+    For native group32 operands, split_k optionally overrides the positive
+    partition count without changing configured backend selection.
+    """
+    is_group32 = (
+        x_scale.dtype in (dtypes.fp8_e8m0, torch.uint8)
+        and w_scale.dtype in (dtypes.fp8_e8m0, torch.uint8)
+        and XQ.ndim == WQ.ndim == 2
+        and x_scale.shape == (XQ.shape[0], XQ.shape[1] // 32)
+        and w_scale.shape
+        in (
+            (WQ.shape[0], WQ.shape[1] // 32),
+            (-(-WQ.shape[0] // 32), WQ.shape[1] // 32),
+        )
+    )
+    # A malformed byte-scale layout must not fall through to FP32 CK dispatch.
+    assert (
+        is_group32 or x_scale.dtype == w_scale.dtype == dtypes.fp32
+    ), "Expected E8M0 group32 scale shapes (typed or uint8), or FP32 128x128 scales"
+    assert (
+        split_k is None or is_group32
+    ), "split_k override requires native group32 operands"
+    assert dtype in (dtypes.bf16, dtypes.fp16) or (
+        is_group32 and dtype == dtypes.fp32
+    ), f"Output {dtype=} is currently not supported in gemm_a8w8"
     m = XQ.shape[0]
     n = WQ.shape[0]
     k = XQ.shape[1]
-    Y = torch.empty(m, n, dtype=dtype, device=XQ.device)
     if isBpreshuffled:
+        assert not is_group32, "Group32 FP8 GEMM requires native weights"
         if get_gfx() in ["gfx950"] and m >= 16 and k >= 512 and dtype == dtypes.bf16:
+            Y = torch.empty(m, n, dtype=dtype, device=XQ.device)
             return gfx950_a8w8_blockscale_ASM(XQ, WQ, x_scale, w_scale, Y)
         else:
             assert 0, "asm kernel only support B preshuffle and m >= 16"
-    else:
-        if not _hip_blockscale_supported():
-            return _blockscale_triton(XQ, WQ, x_scale, w_scale, dtype)
-        config = get_CKGEMM_config(
-            m, n, k, AITER_CONFIGS.AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_FILE
+
+    tuned_file = (
+        AITER_CONFIGS.AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_GROUP32_FILE
+        if is_group32
+        else AITER_CONFIGS.AITER_CONFIG_GEMM_A8W8_BLOCKSCALE_FILE
+    )
+    config = get_CKGEMM_config(m, n, k, tuned_file)
+    if config is not None:
+        libtype = config["libtype"]
+        if libtype == "triton":
+            return _blockscale_triton(
+                XQ, WQ, x_scale, w_scale, dtype, group32=is_group32, split_k=split_k
+            )
+        # CK/CKTile currently consume FP32 128x128 scales. A misconfigured
+        # group32 row must fail instead of reinterpreting its E8M0 bytes.
+        assert not is_group32, f"Unsupported libtype {libtype} for group32 GEMM"
+        splitK = int(config.get("splitK", 0))
+        kernelName = str(config.get("kernelName", ""))
+        Y = torch.empty(m, n, dtype=dtype, device=XQ.device)
+        if libtype == "ck":
+            return gemm_a8w8_blockscale_ck(
+                XQ,
+                WQ,
+                x_scale,
+                w_scale,
+                Y,
+                splitK=splitK,
+                kernelName=kernelName,
+            )
+        elif libtype == "cktile":
+            return gemm_a8w8_blockscale_cktile(
+                XQ,
+                WQ,
+                x_scale,
+                w_scale,
+                Y,
+                splitK=splitK,
+                kernelName=kernelName,
+            )
+        else:
+            assert 0, f"Unsupported libtype {libtype} for gemm_a8w8_blockscale"
+
+    if is_group32 or not _hip_blockscale_supported():
+        return _blockscale_triton(
+            XQ, WQ, x_scale, w_scale, dtype, group32=is_group32, split_k=split_k
         )
-        if config is not None:
-            libtype = config["libtype"]
-            splitK = int(config.get("splitK", 0))
-            kernelName = str(config.get("kernelName", ""))
-            if libtype == "ck":
-                return gemm_a8w8_blockscale_ck(
-                    XQ,
-                    WQ,
-                    x_scale,
-                    w_scale,
-                    Y,
-                    splitK=splitK,
-                    kernelName=kernelName,
-                )
-            elif libtype == "cktile":
-                return gemm_a8w8_blockscale_cktile(
-                    XQ,
-                    WQ,
-                    x_scale,
-                    w_scale,
-                    Y,
-                    splitK=splitK,
-                    kernelName=kernelName,
-                )
-            else:
-                assert 0, f"Unsupported libtype {libtype} for gemm_a8w8_blockscale"
-        min_m = _BLOCKSCALE_TRITON_FALLBACK_MIN_M.get(get_gfx())
-        if min_m is not None and m >= min_m:
-            return _blockscale_triton(XQ, WQ, x_scale, w_scale, dtype)
-        try:
-            return gemm_a8w8_blockscale_ck(XQ, WQ, x_scale, w_scale, Y)
-        except RuntimeError as e:
-            raise RuntimeError(
-                f"gemm_a8w8_blockscale failed for shape M={m}, N={n}, K={k}, "
-                f"{dtype=}, config={config}: {e}"
-            ) from e
+    min_m = _BLOCKSCALE_TRITON_FALLBACK_MIN_M.get(get_gfx())
+    if min_m is not None and m >= min_m:
+        return _blockscale_triton(XQ, WQ, x_scale, w_scale, dtype)
+    Y = torch.empty(m, n, dtype=dtype, device=XQ.device)
+    try:
+        return gemm_a8w8_blockscale_ck(XQ, WQ, x_scale, w_scale, Y)
+    except RuntimeError as e:
+        raise RuntimeError(
+            f"gemm_a8w8_blockscale failed for shape M={m}, N={n}, K={k}, "
+            f"{dtype=}, config={config}: {e}"
+        ) from e
 
 
 def flatmm_a8w8_blockscale_ASM(
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+gfx,cu_num,M,N,K,libtype,kernelId,splitK,us,kernelName,tflops,bw,errRatio`