Add Mistral Large 3 support. (#14213)

Co-authored-by: elvischenv <219235043+elvischenv@users.noreply.github.com>
Co-authored-by: Linda-Stadter <57756729+Linda-Stadter@users.noreply.github.com>

python/sglang/srt/layers/quantization/fp8_utils.py

@@ -971,3 +971,46 @@ def apply_fp8_ptpc_linear(
     if bias is not None:
         output = output + bias
     return output.view(*output_shape)
+
+
+def validate_fp8_block_shape(
+    layer: torch.nn.Module,
+    input_size: int,
+    output_size: int,
+    input_size_per_partition: int,
+    output_partition_sizes: list[int],
+    block_size: list[int],
+) -> None:
+    """Validate block quantization shapes for tensor parallelism."""
+    from sglang.srt.distributed import get_tensor_model_parallel_world_size
+
+    tp_size = getattr(layer, "tp_size", get_tensor_model_parallel_world_size())
+    block_n, block_k = block_size[0], block_size[1]
+
+    # Required by row parallel
+    if (
+        tp_size > 1
+        and input_size // input_size_per_partition == tp_size
+        and input_size_per_partition % block_k != 0
+    ):
+        raise ValueError(
+            f"Weight input_size_per_partition = {input_size_per_partition} "
+            f"is not divisible by weight quantization block_k = {block_k}."
+        )
+
+    # Required by column parallel or enabling merged weights
+    is_tp_split = tp_size > 1 and output_size // sum(output_partition_sizes) == tp_size
+    is_merged_gemm = len(output_partition_sizes) > 1
+    if is_tp_split or is_merged_gemm:
+        sizes_to_check = output_partition_sizes
+        if not is_tp_split and is_merged_gemm:
+            # In case of merged matrices, we allow the last
+            # matrix to not be a multiple of block size
+            sizes_to_check = output_partition_sizes[:-1]
+        for output_partition_size in sizes_to_check:
+            if output_partition_size % block_n != 0:
+                raise ValueError(
+                    f"Weight output_partition_size = "
+                    f"{output_partition_size} is not divisible by "
+                    f"weight quantization block_n = {block_n}."
+                )