Cycles: Enable OptiX on first generation Maxwell GPUs again

Referenced by issue #77348, Blender LTS: Maintenance Task 2.83

intern/cycles/device/device_optix.cpp

@@ -1543,11 +1543,10 @@ void device_optix_info(const vector<DeviceInfo> &cuda_devices, vector<DeviceInfo
   for (DeviceInfo info : cuda_devices) {
     assert(info.type == DEVICE_CUDA);
 
-    int major, minor;
+    int major;
     cuDeviceGetAttribute(&major, CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR, info.num);
-    cuDeviceGetAttribute(&minor, CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR, info.num);
-    if (major < 5 || (major == 5 && minor < 2)) {
-      continue;  // Only Maxwell 2.0 and up are supported by OptiX
+    if (major < 5) {
+      continue;  // Only Maxwell and up are supported by OptiX
     }
 
     info.type = DEVICE_OPTIX;

intern/cycles/kernel/CMakeLists.txt

@@ -549,7 +549,7 @@ if(WITH_CYCLES_DEVICE_OPTIX AND WITH_CYCLES_CUDA_BINARIES)
           ${SRC_UTIL_HEADERS}
         COMMAND ${CUBIN_CC_ENV}
             "$<TARGET_FILE:cycles_cubin_cc>"
-            -target 52
+            -target 50
             -ptx
             -i ${CMAKE_CURRENT_SOURCE_DIR}/${input}
             ${cuda_flags}
@@ -573,7 +573,7 @@ if(WITH_CYCLES_DEVICE_OPTIX AND WITH_CYCLES_CUDA_BINARIES)
         COMMAND
           ${CUDA_NVCC_EXECUTABLE}
           --ptx
-          -arch=sm_52
+          -arch=sm_50
           ${cuda_flags}
           ${input}
         WORKING_DIRECTORY