Support CUTLASS NVFP4 (w4a4) for Blackwell Geforce GPUs (SM120) (vllm-project#21309)

Signed-off-by: LopezCastroRoberto <roberto.lopez.castro@udc.es>
Signed-off-by: Diego-Castan <diego.castan@ibm.com>

Author: LopezCastroRoberto

CMakeLists.txt

@@ -529,6 +529,25 @@ if(VLLM_GPU_LANG STREQUAL "CUDA")
     endif()
   endif()
 
+  # The nvfp4_scaled_mm_sm120 kernels for Geforce Blackwell SM120 require
+  # CUDA 12.8 or later
+  cuda_archs_loose_intersection(FP4_ARCHS "12.0;12.0a" "${CUDA_ARCHS}")
+  if(${CMAKE_CUDA_COMPILER_VERSION} VERSION_GREATER_EQUAL 12.8 AND FP4_ARCHS)
+    set(SRCS
+      "csrc/quantization/fp4/nvfp4_quant_kernels.cu"
+      "csrc/quantization/fp4/nvfp4_scaled_mm_sm120_kernels.cu")
+    set_gencode_flags_for_srcs(
+      SRCS "${SRCS}"
+      CUDA_ARCHS "${FP4_ARCHS}")
+    list(APPEND VLLM_EXT_SRC "${SRCS}")
+    list(APPEND VLLM_GPU_FLAGS "-DENABLE_NVFP4_SM120=1")
+    message(STATUS "Building NVFP4 for archs: ${FP4_ARCHS}")
+  else()
+    message(STATUS "Not building NVFP4 as no compatible archs were found.")
+    # clear FP4_ARCHS
+    set(FP4_ARCHS)
+  endif()
+
   # FP4 Archs and flags
   cuda_archs_loose_intersection(FP4_ARCHS "10.0a" "${CUDA_ARCHS}")
   if(${CMAKE_CUDA_COMPILER_VERSION} VERSION_GREATER_EQUAL 12.8 AND FP4_ARCHS)
@@ -541,7 +560,7 @@ if(VLLM_GPU_LANG STREQUAL "CUDA")
       SRCS "${SRCS}"
       CUDA_ARCHS "${FP4_ARCHS}")
     list(APPEND VLLM_EXT_SRC "${SRCS}")
-    list(APPEND VLLM_GPU_FLAGS "-DENABLE_NVFP4=1")
+    list(APPEND VLLM_GPU_FLAGS "-DENABLE_NVFP4_SM100=1")
     list(APPEND VLLM_GPU_FLAGS "-DENABLE_CUTLASS_MOE_SM100=1")
     message(STATUS "Building NVFP4 for archs: ${FP4_ARCHS}")
   else()

csrc/quantization/fp4/nvfp4_blockwise_moe_kernel.cu

@@ -335,7 +335,7 @@ void run_fp4_blockwise_scaled_group_mm(
   TORCH_CHECK(status == cutlass::Status::kSuccess, "Failed to run GEMM");
 }
 
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
 constexpr auto FLOAT4_E2M1X2 = at::ScalarType::Byte;
 constexpr auto SF_DTYPE = at::ScalarType::Float8_e4m3fn;
 #endif
@@ -356,7 +356,7 @@ void cutlass_fp4_group_mm(
     const torch::Tensor& a_blockscale, const torch::Tensor& b_blockscales,
     const torch::Tensor& alphas, const torch::Tensor& problem_sizes,
     const torch::Tensor& expert_offsets, const torch::Tensor& sf_offsets) {
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
   // Input validation
   CHECK_INPUT(a, FLOAT4_E2M1X2, "a");
   CHECK_INPUT(b, FLOAT4_E2M1X2, "b");
@@ -398,7 +398,7 @@ void cutlass_fp4_group_mm(
   TORCH_CHECK_NOT_IMPLEMENTED(
       false,
       "No compiled cutlass_fp4_group_mm kernel, vLLM must "
-      "be compiled with ENABLE_NVFP4 for SM100+ and CUDA "
+      "be compiled with ENABLE_NVFP4_SM100 for SM100+ and CUDA "
       "12.8 or above.");
 #endif
 }

csrc/quantization/fp4/nvfp4_quant_entry.cu

@@ -16,14 +16,15 @@
 
 #include <torch/all.h>
 
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
-void scaled_fp4_quant_sm100a(torch::Tensor const& output,
+#if (defined(ENABLE_NVFP4_SM100) && ENABLE_NVFP4_SM100) || \
+    (defined(ENABLE_NVFP4_SM120) && ENABLE_NVFP4_SM120)
+void scaled_fp4_quant_sm1xxa(torch::Tensor const& output,
                              torch::Tensor const& input,
                              torch::Tensor const& output_sf,
                              torch::Tensor const& input_sf);
 #endif
 
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
 void scaled_fp4_experts_quant_sm100a(
     torch::Tensor& output, torch::Tensor& output_scale,
     torch::Tensor const& input, torch::Tensor const& input_global_scale,
@@ -33,8 +34,9 @@ void scaled_fp4_experts_quant_sm100a(
 
 void scaled_fp4_quant(torch::Tensor& output, torch::Tensor const& input,
                       torch::Tensor& output_sf, torch::Tensor const& input_sf) {
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
-  return scaled_fp4_quant_sm100a(output, input, output_sf, input_sf);
+#if (defined(ENABLE_NVFP4_SM100) && ENABLE_NVFP4_SM100) || \
+    (defined(ENABLE_NVFP4_SM120) && ENABLE_NVFP4_SM120)
+  return scaled_fp4_quant_sm1xxa(output, input, output_sf, input_sf);
 #endif
   TORCH_CHECK_NOT_IMPLEMENTED(false, "No compiled nvfp4 quantization kernel");
 }
@@ -44,7 +46,7 @@ void scaled_fp4_experts_quant(
     torch::Tensor const& input, torch::Tensor const& input_global_scale,
     torch::Tensor const& input_offset_by_experts,
     torch::Tensor const& output_scale_offset_by_experts) {
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
   return scaled_fp4_experts_quant_sm100a(
       output, output_scale, input, input_global_scale, input_offset_by_experts,
       output_scale_offset_by_experts);

csrc/quantization/fp4/nvfp4_quant_kernels.cu

@@ -332,7 +332,7 @@ template void invokeFP4Quantization(int m, int n, __nv_bfloat16 const* input,
                                     int multiProcessorCount,
                                     cudaStream_t stream);
 
-void scaled_fp4_quant_sm100a(torch::Tensor const& output,
+void scaled_fp4_quant_sm1xxa(torch::Tensor const& output,
                              torch::Tensor const& input,
                              torch::Tensor const& output_sf,
                              torch::Tensor const& input_sf) {

csrc/quantization/fp4/nvfp4_scaled_mm_entry.cu

@@ -16,20 +16,30 @@
 
 #include <torch/all.h>
 
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
 void cutlass_scaled_fp4_mm_sm100a(torch::Tensor& D, torch::Tensor const& A,
                                   torch::Tensor const& B,
                                   torch::Tensor const& A_sf,
                                   torch::Tensor const& B_sf,
                                   torch::Tensor const& alpha);
 #endif
 
+#if defined ENABLE_NVFP4_SM120 && ENABLE_NVFP4_SM120
+void cutlass_scaled_fp4_mm_sm120a(torch::Tensor& D, torch::Tensor const& A,
+                                  torch::Tensor const& B,
+                                  torch::Tensor const& A_sf,
+                                  torch::Tensor const& B_sf,
+                                  torch::Tensor const& alpha);
+#endif
+
 void cutlass_scaled_fp4_mm(torch::Tensor& D, torch::Tensor const& A,
                            torch::Tensor const& B, torch::Tensor const& A_sf,
                            torch::Tensor const& B_sf,
                            torch::Tensor const& alpha) {
-#if defined ENABLE_NVFP4 && ENABLE_NVFP4
+#if defined ENABLE_NVFP4_SM100 && ENABLE_NVFP4_SM100
   return cutlass_scaled_fp4_mm_sm100a(D, A, B, A_sf, B_sf, alpha);
+#elif defined ENABLE_NVFP4_SM120 && ENABLE_NVFP4_SM120
+  return cutlass_scaled_fp4_mm_sm120a(D, A, B, A_sf, B_sf, alpha);
 #endif
   TORCH_CHECK_NOT_IMPLEMENTED(false,
                               "No compiled nvfp4 mm kernel, vLLM should "