[CP V1 Deprecation 2/5] Make strategy prefill CP canonical (#36223)

python/sglang/srt/arg_groups/deepseek_v4_hook.py

@@ -168,6 +168,9 @@ def validate_deepseek_v4_cp(server_args: ServerArgs) -> None:
             f"DeepSeekV4 only supports interleave CP strategy, got {cfg.cp_strategy}"
         )
 
+    if get_platform().is_hip or get_platform().is_npu:
+        # Protected platform implementations still consume the legacy runtime
+        # fields. Generic backends use enable_prefill_cp/cp_strategy directly.
         declare_resolution(
             server_args,
             "validate_deepseek_v4_cp",

python/sglang/srt/arg_groups/parallel_hook.py

@@ -31,35 +31,36 @@ def handle_context_parallelism(server_args: Any):
 
     cfg = resolving_view(server_args)
     if parse_connector_type(cfg.model_path) != ConnectorType.INSTANCE:
-        from sglang.srt.configs.model_config import is_deepseek_dsa
-        from sglang.srt.layers.cp.utils import CP_V2_DEFAULT_MODEL_CLASSES
-
         model_config = model_config_of(server_args)
         hf_config = model_config.hf_config
         model_arch = hf_config.architectures[0]
-        if model_arch in CP_V2_DEFAULT_MODEL_CLASSES:
+        platform = get_platform()
-            is_dsa_default_model = is_deepseek_dsa(hf_config)
-            # DSA CP-v2 currently supports only the interleave strategy.
-            enable_default_cp_v2 = not is_dsa_default_model or (
-                cfg.enable_prefill_cp and cfg.cp_strategy == "interleave"
-            )
-            if enable_default_cp_v2 and not envs.SGLANG_ENABLE_CP_V2.is_set():
-                envs.SGLANG_ENABLE_CP_V2.set(True)
-
         if (
             cfg.enable_prefill_cp
-            and model_arch in ("MiMoV2ForCausalLM", "MiMoV2FlashForCausalLM")
+            and model_arch == "DeepseekV32ForCausalLM"
-            and envs.SGLANG_ENABLE_CP_V2.get()
+            and cfg.cp_strategy == "zigzag"
+            and not (platform.is_hip or platform.is_npu)
+        ):
+            raise ValueError(
+                "DeepSeek V3.2 prefill CP does not support --cp-strategy "
+                "zigzag; use interleave."
+            )
+        if cfg.enable_prefill_cp and model_arch in (
+            "MiMoV2ForCausalLM",
+            "MiMoV2FlashForCausalLM",
         ):
             if cfg.cp_strategy != "zigzag":
-                raise ValueError("MiMo V2 CP-v2 only supports --cp-strategy zigzag.")
+                raise ValueError(
+                    "MiMo V2 prefill CP only supports --cp-strategy zigzag."
+                )
             if (
                 model_config.is_multimodal
                 and not cfg.language_only
                 and not cfg.language_model_only
             ):
                 raise ValueError(
-                    "MiMo V2 CP-v2 only supports text inference; add --language-only."
+                    "MiMo V2 prefill CP only supports text inference; add "
+                    "--language-only."
                 )
 
     if cfg.enable_prefill_cp and cfg.cp_strategy is None:
@@ -559,43 +560,62 @@ def handle_eplb_and_dispatch(server_args: Any):
         assert resolved_view(server_args).ep_size > 1
 
 
-def handle_legacy_cp_arguments(server_args: Any):
+def handle_platform_cp_compatibility(server_args: Any):
     cfg = resolving_view(server_args)
+    platform = get_platform()
+    is_protected_platform = platform.is_hip or platform.is_npu
+    if not is_protected_platform:
+        if (
+            server_args.enable_prefill_context_parallel
+            or server_args.enable_dsa_prefill_context_parallel
+        ):
+            raise ValueError(
+                "Legacy prefill context-parallel options are supported only "
+                "by protected HIP or Ascend NPU paths. Use "
+                "--enable-prefill-cp with --cp-strategy."
+            )
+        return
+
     legacy_mode_to_strategy = {
         "in-seq-split": "zigzag",
         "round-robin-split": "interleave",
     }
-    strategy_to_legacy_mode = {
-        "zigzag": "in-seq-split",
-        "interleave": "round-robin-split",
-    }
 
     if cfg.enable_prefill_context_parallel or cfg.enable_dsa_prefill_context_parallel:
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_platform_cp_compatibility",
             enable_prefill_cp=True,
         )
 
     if cfg.enable_prefill_context_parallel and cfg.cp_strategy is None:
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_platform_cp_compatibility",
             cp_strategy=legacy_mode_to_strategy[cfg.prefill_cp_mode],
         )
     if cfg.enable_dsa_prefill_context_parallel and cfg.cp_strategy is None:
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_platform_cp_compatibility",
             cp_strategy=legacy_mode_to_strategy[cfg.dsa_prefill_cp_mode],
         )
 
+
+def handle_legacy_cp_runtime_compatibility(server_args: Any):
+    """Project canonical CP settings for runtime consumers removed by PR3."""
+    cfg = resolving_view(server_args)
+
     if cfg.enable_prefill_context_parallel and cfg.enable_dsa_prefill_context_parallel:
         return
 
     if not cfg.enable_prefill_cp or cfg.cp_strategy is None:
         return
 
+    strategy_to_legacy_mode = {
+        "zigzag": "in-seq-split",
+        "interleave": "round-robin-split",
+    }
     mode = strategy_to_legacy_mode[cfg.cp_strategy]
     use_dsa_legacy_aliases = cfg.enable_dsa_prefill_context_parallel or getattr(
         resolved_view(server_args), "attention_backend", None
@@ -603,28 +623,28 @@ def handle_legacy_cp_arguments(server_args: Any):
     if use_dsa_legacy_aliases:
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_legacy_cp_runtime_compatibility",
             enable_dsa_prefill_context_parallel=True,
         )
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_legacy_cp_runtime_compatibility",
             enable_prefill_context_parallel=False,
         )
     else:
         declare_resolution(
             server_args,
-            "_handle_legacy_cp_arguments",
+            "_handle_legacy_cp_runtime_compatibility",
             enable_prefill_context_parallel=True,
         )
     declare_resolution(
         server_args,
-        "_handle_legacy_cp_arguments",
+        "_handle_legacy_cp_runtime_compatibility",
         dsa_prefill_cp_mode=mode,
     )
     declare_resolution(
         server_args,
-        "_handle_legacy_cp_arguments",
+        "_handle_legacy_cp_runtime_compatibility",
         prefill_cp_mode=mode,
     )
 

python/sglang/srt/arg_groups/pipeline.py

@@ -146,8 +146,8 @@ def run_resolution_pipeline(server_args: Any) -> None:
 
     handle_pd_disaggregation(server_args)
 
-    # Normalize deprecated CP aliases before validations or model-specific
+    # Normalize protected-platform CP aliases before validations or
-    # defaults inspect enable_prefill_cp/cp_strategy.
+    # model-specific defaults inspect enable_prefill_cp/cp_strategy.
     from sglang.srt.arg_groups.parallel_hook import (
         handle_context_parallelism,
         handle_data_parallelism,
@@ -156,10 +156,11 @@ def run_resolution_pipeline(server_args: Any) -> None:
         handle_elastic_ep,
         handle_eplb_and_dispatch,
         handle_expert_distribution_metrics,
-        handle_legacy_cp_arguments,
+        handle_legacy_cp_runtime_compatibility,
+        handle_platform_cp_compatibility,
     )
 
-    handle_legacy_cp_arguments(server_args)
+    handle_platform_cp_compatibility(server_args)
     from sglang.srt.arg_groups.kv_cache_hook import (
         handle_cache_compatibility,
         handle_kv4_compatibility,
@@ -286,9 +287,9 @@ def run_resolution_pipeline(server_args: Any) -> None:
     # Normalize load balancing defaults.
     handle_load_balance_method(server_args)
 
-    # Re-apply after model-specific defaults resolve attention_backend so
+    # The old runtime distinguishes DSA from other CP paths through legacy
-    # canonical CP mirrors to the right legacy runtime aliases.
+    # fields, so project only after attention_backend has been resolved.
-    handle_legacy_cp_arguments(server_args)
+    handle_legacy_cp_runtime_compatibility(server_args)
 
     # Handle context parallelism.
     handle_context_parallelism(server_args)

python/sglang/srt/environ.py

@@ -677,7 +677,6 @@ class Envs:
     # ===================================================================
     # Distributed and model-parallel runtime
     # ===================================================================
-    SGLANG_ENABLE_CP_V2 = EnvBool(False)
     SGLANG_ONE_VISIBLE_DEVICE_PER_PROCESS = EnvBool(False)
     # Comma-separated bundle indices for Ray Custom PG mode (e.g., "0,1,2,7").
     SGLANG_RAY_BUNDLE_INDICES = EnvStr("")
@@ -1753,6 +1752,9 @@ _DEPRECATED_ENVS: Dict[str, _DeprecatedEnv] = {
         note="Note the unit change: milliseconds -> seconds.",
     ),
     # Removed without replacement.
+    "SGLANG_ENABLE_CP_V2": _DeprecatedEnv(
+        note="Strategy-based prefill context parallelism is now the only generic implementation."
+    ),
     "SGLANG_PER_TOKEN_GROUP_QUANT_8BIT_V2": _DeprecatedEnv(),
     # Superseded by the unified JIT per_token_group_quant, the default CUDA path.
     "SGLANG_OPT_USE_JIT_PER_TOKEN_GROUP_QUANT": _DeprecatedEnv(),

python/sglang/srt/layers/attention/dsa/utils.py

@@ -18,7 +18,7 @@ from sglang.srt.runtime_context import (
     get_parallel,
     process_model_config,
 )
-from sglang.srt.utils import get_bool_env_var, is_cuda, is_hip
+from sglang.srt.utils import get_bool_env_var, is_cuda, is_hip, is_npu
 from sglang.srt.utils.common import ceil_align, ceil_div
 
 
@@ -105,12 +105,11 @@ def should_use_dsa_fused_topk(seed_dsa_topk_from_draft_extend: bool) -> bool:
 
 
 def is_dsa_enable_prefill_cp():
-    if not envs.SGLANG_ENABLE_CP_V2.get():
+    if is_hip() or is_npu():
         return get_parallel().enable_dsa_prefill_context_parallel
 
-    # Derive from the runtime CP topology + model arch rather than the legacy
+    # Generic prefill CP derives activation from the runtime topology and model
-    # flag under CP-v2: DSA prefill CP is active when the CP group is on for a
+    # architecture. Protected HIP/NPU paths continue to use their legacy field.
-    # DeepSeek Sparse Attention model.
     if get_parallel().attn_cp_size <= 1:
         return False
     from sglang.srt.configs.model_config import is_deepseek_dsa, is_deepseek_v4

python/sglang/srt/layers/cp/utils.py

@@ -40,18 +40,6 @@ from sglang.srt.runtime_context import get_parallel
 if TYPE_CHECKING:
     from sglang.srt.model_executor.model_runner import ModelRunner
 
-CP_V2_DEFAULT_MODEL_CLASSES = frozenset(
-    {
-        "DeepseekV32ForCausalLM",
-        "GlmMoeDsaForCausalLM",
-        "GptOssForCausalLM",
-        "MiMoV2FlashForCausalLM",
-        "MiMoV2ForCausalLM",
-        "Qwen3MoeForCausalLM",
-        "DeepseekV3ForCausalLM",
-    }
-)
-
 
 def is_glm_dsa_cache_layer_split_enabled(model_runner: "ModelRunner") -> bool:
     """Whether DSA GPU KV/indexer cache layers are sharded across CP ranks.
@@ -130,10 +118,10 @@ def get_layer_owner(local_layer_idx: int, shard_size: int, total_layers: int) ->
 
 
 def enable_cp_v2() -> bool:
-    """Return whether the CP-v2 path is enabled for this process."""
+    """Return whether the strategy-based generic prefill CP path is available."""
-    from sglang.srt.environ import envs
+    from sglang.srt.utils import is_hip, is_npu
 
-    return bool(envs.SGLANG_ENABLE_CP_V2.get())
+    return not (is_hip() or is_npu())
 
 
 def is_cp_v2_active(forward_batch) -> bool:
@@ -322,7 +310,6 @@ __all__ = [
     "InterleaveContextParallelMetadata",
     "ZigzagCPStrategy",
     "ZigzagContextParallelMetadata",
-    "CP_V2_DEFAULT_MODEL_CLASSES",
     "enable_cp_v2",
     "get_cp_strategy",
     "is_cp_v2_active",

python/sglang/srt/server_args.py

@@ -4019,13 +4019,6 @@ class ServerArgs:
             dest="cuda_graph_max_bs_prefill",
             help="Deprecated alias for --cuda-graph-max-bs-prefill.",
         )
-        parser.add_argument(
-            "--enable-dsa-prefill-context-parallel",
-            dest="enable_dsa_prefill_context_parallel",
-            action=DeprecatedStoreTrueAction,
-            new_flag="--enable-prefill-cp",
-            help="[Deprecated] Use --enable-prefill-cp instead.",
-        )
         parser.add_argument(
             "--enable-nsa-prefill-context-parallel",
             dest="enable_dsa_prefill_context_parallel",
@@ -4047,20 +4040,6 @@ class ServerArgs:
             new_flag="--enable-prefill-cp",
             help="[Deprecated] Use --enable-prefill-cp instead.",
         )
-        parser.add_argument(
-            "--dsa-prefill-cp-mode",
-            dest="dsa_prefill_cp_mode",
-            action=DeprecatedAliasStoreAction,
-            new_flag="--cp-strategy",
-            type=str,
-            default=ServerArgs.dsa_prefill_cp_mode,
-            choices=["in-seq-split", "round-robin-split"],
-            help=(
-                "[Deprecated] Use --cp-strategy {zigzag,interleave} instead. "
-                "'in-seq-split' maps to 'zigzag'; 'round-robin-split' maps to "
-                "'interleave'."
-            ),
-        )
         parser.add_argument(
             "--nsa-prefill-cp-mode",
             dest="dsa_prefill_cp_mode",
@@ -4071,19 +4050,6 @@ class ServerArgs:
             choices=["in-seq-split", "round-robin-split"],
             help="[Deprecated] Use --cp-strategy instead.",
         )
-        parser.add_argument(
-            "--prefill-cp-mode",
-            dest="prefill_cp_mode",
-            action=DeprecatedAliasStoreAction,
-            new_flag="--cp-strategy",
-            type=str,
-            default=ServerArgs.prefill_cp_mode,
-            choices=["in-seq-split"],
-            help=(
-                "[Deprecated] Use --cp-strategy {zigzag,interleave} instead. "
-                "'in-seq-split' maps to 'zigzag'."
-            ),
-        )
         parser.add_argument(
             "--enable-flashinfer-allreduce-fusion",
             action="store_true",

test/registered/cp/test_cp_strategy_unit.py

@@ -5,6 +5,7 @@ from unittest.mock import patch
 
 import torch
 
+from sglang.srt.layers.attention.dsa.utils import is_dsa_enable_prefill_cp
 from sglang.srt.layers.cp.base import (
     ContextParallelStrategyKind,
     get_cp_strategy,
@@ -94,13 +95,44 @@ class TestCPStrategyUnit(CustomTestCase):
             cp_strategy="interleave",
         )
 
-        with patch(
-            "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get", return_value=True
-        ):
         self.assertIsNotNone(get_cp_strategy())
         self.assertTrue(is_cp_enabled())
         self.assertTrue(is_interleave())
 
+    def test_hip_dsa_cp_uses_protected_legacy_runtime_flag(self):
+        parallel = SimpleNamespace(
+            enable_dsa_prefill_context_parallel=False,
+            attn_cp_size=2,
+        )
+        model_config = SimpleNamespace(hf_config=SimpleNamespace())
+
+        with (
+            patch(
+                "sglang.srt.layers.attention.dsa.utils.get_parallel",
+                return_value=parallel,
+            ),
+            patch(
+                "sglang.srt.layers.attention.dsa.utils.process_model_config",
+                return_value=model_config,
+            ),
+            patch("sglang.srt.layers.attention.dsa.utils.is_hip", return_value=True),
+            patch(
+                "sglang.srt.configs.model_config.is_deepseek_dsa",
+                return_value=True,
+            ),
+        ):
+            self.assertFalse(is_dsa_enable_prefill_cp())
+
+    @patch("sglang.srt.utils.is_npu", return_value=False)
+    @patch("sglang.srt.utils.is_hip", return_value=True)
+    def test_hip_keeps_strategy_cp_disabled(self, _mock_is_hip, _mock_is_npu):
+        self.assertFalse(enable_cp_v2())
+
+    @patch("sglang.srt.utils.is_npu", return_value=True)
+    @patch("sglang.srt.utils.is_hip", return_value=False)
+    def test_npu_keeps_strategy_cp_disabled(self, _mock_is_hip, _mock_is_npu):
+        self.assertFalse(enable_cp_v2())
+
 
 class TestPrefillCPBCGReplay(CustomTestCase):
     def tearDown(self):
@@ -155,10 +187,6 @@ class TestPrefillCPBCGReplay(CustomTestCase):
         self._enable_zigzag()
 
         with (
-            patch(
-                "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get",
-                return_value=True,
-            ),
             patch(
                 "sglang.srt.layers.cp.bcg.get_cp_padding_align_size",
                 return_value=8,
@@ -209,10 +237,6 @@ class TestPrefillCPBCGReplay(CustomTestCase):
 
         with (
             get_parallel().override(attn_cp_rank=0, attn_cp_size=4),
-            patch(
-                "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get",
-                return_value=True,
-            ),
             patch(
                 "sglang.srt.layers.cp.bcg.get_cp_padding_align_size",
                 return_value=8,
@@ -243,10 +267,6 @@ class TestPrefillCPBCGReplay(CustomTestCase):
 
         with (
             get_parallel().override(attn_cp_rank=0, attn_cp_size=4),
-            patch(
-                "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get",
-                return_value=True,
-            ),
             patch(
                 "sglang.srt.layers.cp.bcg.get_cp_padding_align_size",
                 return_value=8,
@@ -298,9 +318,7 @@ class TestCPZigzagStrategy(CustomTestCase):
             extend_seq_lens_cpu=[7],
         )
 
-        with patch(
+        with patch.dict("os.environ", {"SGLANG_ENABLE_CP_V2": "0"}):
-            "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get", return_value=True
-        ):
             self.assertTrue(enable_cp_v2())
             self.assertTrue(is_cp_v2_active(active_batch))
             self.assertFalse(is_cp_v2_active(inactive_batch))
@@ -494,9 +512,6 @@ class TestCPZigzagStrategy(CustomTestCase):
 
             local_x = strategy.shard_hidden_states(x, fb)
             local_positions = strategy.shard_position_ids(positions, fb)
-            with patch(
-                "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get", return_value=True
-            ):
             helper_x, helper_positions = cp_split_before_forward(
                 x,
                 positions,
@@ -916,10 +931,6 @@ class TestCPInterleaveStrategy(CustomTestCase):
 
         with (
             get_parallel().override(attn_cp_rank=2, attn_cp_size=4),
-            patch(
-                "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get",
-                return_value=True,
-            ),
             patch(
                 "sglang.srt.layers.cp.padding.get_cp_padding_align_size",
                 return_value=4,
@@ -965,10 +976,6 @@ class TestCPInterleaveStrategy(CustomTestCase):
                 local_x = strategy.shard_hidden_states(x, fb)
                 local_positions = strategy.shard_position_ids(positions, fb)
 
-                with patch(
-                    "sglang.srt.environ.envs.SGLANG_ENABLE_CP_V2.get",
-                    return_value=True,
-                ):
                 helper_x, helper_positions = cp_split_before_forward(
                     x,
                     positions,

test/registered/unit/server_args/test_server_args.py

@@ -47,7 +47,8 @@ from sglang.srt.arg_groups.overrides import (
 from sglang.srt.arg_groups.parallel_hook import (
     handle_context_parallelism,
     handle_data_parallelism,
-    handle_legacy_cp_arguments,
+    handle_legacy_cp_runtime_compatibility,
+    handle_platform_cp_compatibility,
 )
 from sglang.srt.arg_groups.pd_disaggregation_hook import handle_pd_disaggregation
 from sglang.srt.arg_groups.serving_hook import (
@@ -1056,52 +1057,116 @@ class TestContextParallelServerArgs(CustomTestCase):
         with self.assertRaisesRegex(ValueError, "--cp-strategy"):
             handle_context_parallelism(server_args)
 
-    def test_deprecated_dsa_cp_mode_maps_to_unified_strategy(self):
+    @override_platform(is_hip=False, is_npu=False)
+    def test_deepseek_v32_prefill_cp_rejects_zigzag(self):
+        server_args = self._new_cp_args(
+            model_path="deepseek-ai/DeepSeek-V3.2",
+            enable_prefill_cp=True,
+            cp_strategy="zigzag",
+        )
+        server_args._model_config = SimpleNamespace(
+            hf_config=SimpleNamespace(architectures=["DeepseekV32ForCausalLM"]),
+            is_multimodal=False,
+        )
+
+        with self.assertRaisesRegex(ValueError, "DeepSeek V3.2.*interleave"):
+            handle_context_parallelism(server_args)
+
+    @override_platform(is_hip=False, is_npu=False)
+    def test_generic_canonical_cp_mirrors_to_transitional_runtime_fields(self):
+        cases = (
+            (
+                "zigzag_mla_or_gqa",
+                "zigzag",
+                "fa3",
+                True,
+                False,
+                "in-seq-split",
+            ),
+            (
+                "interleave_dsa",
+                "interleave",
+                "dsa",
+                False,
+                True,
+                "round-robin-split",
+            ),
+        )
+
+        for name, strategy, backend, expect_generic, expect_dsa, mode in cases:
+            with self.subTest(name=name):
+                server_args = self._new_cp_args(
+                    enable_prefill_cp=True,
+                    cp_strategy=strategy,
+                    attention_backend=backend,
+                )
+
+                handle_platform_cp_compatibility(server_args)
+
+                self.assertFalse(
+                    resolution_result(server_args, "enable_prefill_context_parallel")
+                )
+                self.assertFalse(
+                    resolution_result(
+                        server_args, "enable_dsa_prefill_context_parallel"
+                    )
+                )
+
+                handle_legacy_cp_runtime_compatibility(server_args)
+
+                self.assertEqual(
+                    resolution_result(server_args, "enable_prefill_context_parallel"),
+                    expect_generic,
+                )
+                self.assertEqual(
+                    resolution_result(
+                        server_args, "enable_dsa_prefill_context_parallel"
+                    ),
+                    expect_dsa,
+                )
+                self.assertEqual(
+                    resolution_result(server_args, "dsa_prefill_cp_mode"), mode
+                )
+                self.assertEqual(
+                    resolution_result(server_args, "prefill_cp_mode"), mode
+                )
+
+    @override_platform(is_hip=False, is_npu=False)
+    def test_non_platform_legacy_prefill_cp_is_rejected(self):
+        server_args = ServerArgs(
+            model_path="instance://127.0.0.1:8000/dummy",
+            enable_prefill_context_parallel=True,
+        )
+        with self.assertRaisesRegex(ValueError, "HIP or Ascend NPU"):
+            handle_platform_cp_compatibility(server_args)
+
+    def test_generic_v1_cp_options_are_not_public_cli(self):
+        removed_options = (
+            ("--enable-dsa-prefill-context-parallel", []),
+            ("--dsa-prefill-cp-mode", ["round-robin-split"]),
+            ("--prefill-cp-mode", ["in-seq-split"]),
+        )
+
+        for option, values in removed_options:
+            with self.subTest(option=option), self.assertRaises(SystemExit):
+                self.parser.parse_args(["--model", "dummy", option, *values])
+
+    def test_npu_cp_compatibility_options_remain_public_cli(self):
         args = self.parser.parse_args(
             [
                 "--model",
                 "dummy",
-                "--enable-dsa-prefill-context-parallel",
+                "--enable-prefill-context-parallel",
-                "--dsa-prefill-cp-mode",
+                "--enable-nsa-prefill-context-parallel",
+                "--nsa-prefill-cp-mode",
                 "round-robin-split",
             ]
         )
-        server_args = self._new_cp_args(
-            enable_dsa_prefill_context_parallel=(
-                resolution_result(args, "enable_dsa_prefill_context_parallel")
-            ),
-            dsa_prefill_cp_mode=resolution_result(args, "dsa_prefill_cp_mode"),
-        )
 
-        handle_legacy_cp_arguments(server_args)
+        self.assertTrue(resolution_result(args, "enable_prefill_context_parallel"))
-
+        self.assertTrue(resolution_result(args, "enable_dsa_prefill_context_parallel"))
-        self.assertTrue(resolution_result(server_args, "enable_prefill_cp"))
-        self.assertEqual(resolution_result(server_args, "cp_strategy"), "interleave")
         self.assertEqual(
-            resolution_result(server_args, "dsa_prefill_cp_mode"), "round-robin-split"
+            resolution_result(args, "dsa_prefill_cp_mode"), "round-robin-split"
-        )
-
-    def test_canonical_interleave_cp_mirrors_to_dsa_runtime_aliases(self):
-        server_args = self._new_cp_args(
-            enable_prefill_cp=True,
-            cp_strategy="interleave",
-            attention_backend="dsa",
-        )
-
-        handle_legacy_cp_arguments(server_args)
-        handle_context_parallelism(server_args)
-
-        self.assertTrue(
-            resolution_result(server_args, "enable_dsa_prefill_context_parallel")
-        )
-        self.assertFalse(
-            resolution_result(server_args, "enable_prefill_context_parallel")
-        )
-        self.assertEqual(
-            resolution_result(server_args, "dsa_prefill_cp_mode"), "round-robin-split"
-        )
-        self.assertEqual(
-            resolution_result(server_args, "prefill_cp_mode"), "round-robin-split"
         )
 
     def test_context_parallel_handler_initializes_cp_strategy(self):
@@ -1117,97 +1182,6 @@ class TestContextParallelServerArgs(CustomTestCase):
         self.assertTrue(is_cp_enabled())
         self.assertTrue(is_interleave())
 
-    def test_registered_cp_legacy_args_map_to_unified_strategy(self):
-        cases = [
-            (
-                "deepseek_v3_mla_cp",
-                dict(enable_prefill_context_parallel=True),
-                "zigzag",
-                "in-seq-split",
-                False,
-                True,
-            ),
-            (
-                "qwen3_gqa_cp",
-                dict(
-                    enable_prefill_context_parallel=True,
-                    tp_size=4,
-                    attn_cp_size=2,
-                ),
-                "zigzag",
-                "in-seq-split",
-                False,
-                True,
-            ),
-            (
-                "deepseek_v32_dsa_in_seq_split",
-                dict(
-                    enable_dsa_prefill_context_parallel=True,
-                    dsa_prefill_cp_mode="in-seq-split",
-                    tp_size=8,
-                    dp_size=2,
-                    attn_cp_size=4,
-                ),
-                "zigzag",
-                "in-seq-split",
-                True,
-                False,
-            ),
-            (
-                "deepseek_v32_dsa_round_robin_split",
-                dict(
-                    enable_dsa_prefill_context_parallel=True,
-                    tp_size=8,
-                    attn_cp_size=8,
-                ),
-                "interleave",
-                "round-robin-split",
-                True,
-                False,
-            ),
-            (
-                "deepseek_v4_flash_fp4_b200_dsa_round_robin_split",
-                dict(
-                    enable_dsa_prefill_context_parallel=True,
-                    dsa_prefill_cp_mode="round-robin-split",
-                    tp_size=4,
-                    attn_cp_size=4,
-                ),
-                "interleave",
-                "round-robin-split",
-                True,
-                False,
-            ),
-        ]
-
-        for name, overrides, strategy, mode, expect_dsa, expect_generic in cases:
-            with self.subTest(name=name):
-                server_args = self._new_cp_args(**overrides)
-
-                handle_legacy_cp_arguments(server_args)
-                handle_context_parallelism(server_args)
-
-                self.assertTrue(resolution_result(server_args, "enable_prefill_cp"))
-                self.assertEqual(
-                    resolution_result(server_args, "cp_strategy"), strategy
-                )
-                self.assertEqual(
-                    resolution_result(server_args, "dsa_prefill_cp_mode"), mode
-                )
-                self.assertEqual(
-                    resolution_result(server_args, "prefill_cp_mode"), mode
-                )
-                self.assertEqual(
-                    resolution_result(
-                        server_args, "enable_dsa_prefill_context_parallel"
-                    ),
-                    expect_dsa,
-                )
-                self.assertEqual(
-                    resolution_result(server_args, "enable_prefill_context_parallel"),
-                    expect_generic,
-                )
-
 
 class TestPortArgs(unittest.TestCase):
     @patch("sglang.srt.server_args.tempfile.NamedTemporaryFile")
@@ -1804,7 +1778,6 @@ class TestPrefillOnlyDisableKvCache(unittest.TestCase):
 
     def _validate_prefill_only_args(self, **overrides):
         sa = ServerArgs(**self._base_kwargs(**overrides))
-        handle_legacy_cp_arguments(sa)
         validate_prefill_only_disable_kv_cache_args(sa)
         return sa
 
@@ -1830,7 +1803,10 @@ class TestPrefillOnlyDisableKvCache(unittest.TestCase):
 
     def test_rejects_prefill_context_parallel(self):
         with self.assertRaisesRegex(ValueError, "--enable-prefill-cp"):
-            self._validate_prefill_only_args(enable_prefill_context_parallel=True)
+            self._validate_prefill_only_args(
+                enable_prefill_cp=True,
+                cp_strategy="zigzag",
+            )
 
     def test_rejects_hisparse(self):
         with self.assertRaisesRegex(ValueError, "--enable-hisparse"):