Revert "Corstone-310 FVP update"

This reverts commit de1a9f6e9bdd2243c4158789834ef21ee94fc31c.

Change-Id: I9cc6ba7d595a0606254bf9116517be6095eb5470
diff --git a/scripts/run_ctest.py b/scripts/run_ctest.py
index aa6292f..c2ba672 100755
--- a/scripts/run_ctest.py
+++ b/scripts/run_ctest.py
@@ -116,14 +116,14 @@
 
 def run_corstone_310(args):
     # Verify supported FVP version
-    version = subprocess.check_output(['FVP_Corstone_SSE-310_Ethos-U65', '--version']).decode()
-    supported_version = ['11.18']
+    version = subprocess.check_output(['FVP_Corstone_SSE-310', '--version']).decode()
+    supported_version = ['11.17']
 
     if not [s for s in supported_version if s in version]:
         raise Exception("Incorrect FVP version. Supported versions are '{}'.".format(supported_version))
 
     # FVP executable
-    cmd = ['FVP_Corstone_SSE-310_Ethos-U65']
+    cmd = ['FVP_Corstone_SSE-310']
 
     # NPU configuration
     cmd += ['-C', 'ethosu.num_macs=' + str(args.macs)]
diff --git a/targets/corstone-310/CMakeLists.txt b/targets/corstone-310/CMakeLists.txt
index d943797..127570d 100644
--- a/targets/corstone-310/CMakeLists.txt
+++ b/targets/corstone-310/CMakeLists.txt
@@ -26,7 +26,7 @@
     set(CMAKE_TOOLCHAIN_FILE "${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/toolchain/armclang.cmake")
 endif()
 
-set(ETHOSU_TARGET_NPU_CONFIG "ethos-u65-256" CACHE STRING "NPU configuration")
+set(ETHOSU_TARGET_NPU_CONFIG "ethos-u55-256" CACHE STRING "NPU configuration")
 set(ETHOSU_TARGET_NPU_COUNT 1 CACHE INTERNAL "Number of NPUs")
 set(ETHOSU_TARGET_NPU_TA_COUNT 0 CACHE INTERNAL "Number of timing adapters per NPU")