diff --git a/modules/core/perf/opencl/perf_arithm.cpp b/modules/core/perf/opencl/perf_arithm.cpp
index f6e62da69c395e4ce111375d365edfa6df245c31..cb06ac4793fc2a7db316bc6f3cd54aaa19a5cb5c 100644
--- a/modules/core/perf/opencl/perf_arithm.cpp
+++ b/modules/core/perf/opencl/perf_arithm.cpp
@@ -651,13 +651,13 @@ OCL_PERF_TEST_P(SetIdentityFixture, SetIdentity,
 
 typedef Size_MatType MeanStdDevFixture;
 
-OCL_PERF_TEST_P(MeanStdDevFixture, DISABLED_MeanStdDev,
+OCL_PERF_TEST_P(MeanStdDevFixture, MeanStdDev,
                 ::testing::Combine(OCL_PERF_ENUM(OCL_SIZE_1, OCL_SIZE_2, OCL_SIZE_3), OCL_TEST_TYPES))
 {
     const Size_MatType_t params = GetParam();
     const Size srcSize = get<0>(params);
     const int type = get<1>(params);
-    const double eps = 1e-5;
+    const double eps = 2e-5;
 
     checkDeviceMaxMemoryAllocSize(srcSize, type);
 
@@ -687,7 +687,7 @@ CV_ENUM(NormType, NORM_INF, NORM_L1, NORM_L2)
 typedef std::tr1::tuple<Size, MatType, NormType> NormParams;
 typedef TestBaseWithParam<NormParams> NormFixture;
 
-OCL_PERF_TEST_P(NormFixture, DISABLED_Norm,
+OCL_PERF_TEST_P(NormFixture, Norm,
                 ::testing::Combine(OCL_PERF_ENUM(OCL_SIZE_1, OCL_SIZE_2, OCL_SIZE_3), OCL_TEST_TYPES, NormType::all()))
 {
     const NormParams params = GetParam();
@@ -703,7 +703,7 @@ OCL_PERF_TEST_P(NormFixture, DISABLED_Norm,
 
     OCL_TEST_CYCLE() res = cv::norm(src1, src2, normType);
 
-    SANITY_CHECK(res, 1e-6, ERROR_RELATIVE);
+    SANITY_CHECK(res, 1e-5, ERROR_RELATIVE);
 }
 
 ///////////// Repeat ////////////////////////
diff --git a/modules/core/src/opencl/reduce.cl b/modules/core/src/opencl/reduce.cl
index 4f0d80670820b81b4f1a3b60d032918cc5fa37b8..0f148f3859c213d3e7e5dfd2c626c8e69492d66a 100644
--- a/modules/core/src/opencl/reduce.cl
+++ b/modules/core/src/opencl/reduce.cl
@@ -88,7 +88,7 @@
 #define REDUCE_GLOBAL \
     accumulator += src[0] == zero ? zero : one
 #define SET_LOCAL_1 \
-        localmem[lid] = accumulator
+    localmem[lid] = accumulator
 #define REDUCE_LOCAL_1 \
     localmem[lid - WGS2_ALIGNED] += accumulator
 #define REDUCE_LOCAL_2 \
diff --git a/modules/core/src/stat.cpp b/modules/core/src/stat.cpp
index 2806efeb31144b80e9038b200a576f1f2afcbdd5..932cad682efb0b9f50cb044f5f3dd48ada7ef1b3 100644
--- a/modules/core/src/stat.cpp
+++ b/modules/core/src/stat.cpp
@@ -479,7 +479,8 @@ static bool ocl_sum( InputArray _src, Scalar & res, int sum_op )
     int dbsize = ocl::Device::getDefault().maxComputeUnits();
     size_t wgs = ocl::Device::getDefault().maxWorkGroupSize();
 
-    int ddepth = std::max(CV_32S, depth), dtype = CV_MAKE_TYPE(ddepth, cn);
+    int ddepth = std::max(sum_op == OCL_OP_SUM_SQR ? CV_32F : CV_32S, depth),
+            dtype = CV_MAKE_TYPE(ddepth, cn);
 
     int wgs2_aligned = 1;
     while (wgs2_aligned < (int)wgs)
@@ -501,7 +502,7 @@ static bool ocl_sum( InputArray _src, Scalar & res, int sum_op )
            dbsize, ocl::KernelArg::PtrWriteOnly(db));
 
     size_t globalsize = dbsize * wgs;
-    if (k.run(1, &globalsize, &wgs, true))
+    if (k.run(1, &globalsize, &wgs, false))
     {
         typedef Scalar (*part_sum)(Mat m);
         part_sum funcs[3] = { ocl_part_sum<int>, ocl_part_sum<float>, ocl_part_sum<double> },
@@ -1927,8 +1928,9 @@ static bool ocl_norm( InputArray _src, int normType, double & result )
         Scalar s;
         bool unstype = depth == CV_8U || depth == CV_16U;
 
-        ocl_sum(src.reshape(1), s, normType == NORM_L2 ?
-                    OCL_OP_SUM_SQR : (unstype ? OCL_OP_SUM : OCL_OP_SUM_ABS) );
+        if ( !ocl_sum(src.reshape(1), s, normType == NORM_L2 ?
+                    OCL_OP_SUM_SQR : (unstype ? OCL_OP_SUM : OCL_OP_SUM_ABS)) )
+            return false;
         result = normType == NORM_L1 ? s[0] : std::sqrt(s[0]);
     }
 
diff --git a/modules/core/test/ocl/test_arithm.cpp b/modules/core/test/ocl/test_arithm.cpp
index 03d84221827b7d8c189f4a42583b6b1cdb3f155a..607e906bd2ba9fd508ae3b85a290d14b3fc06fe5 100644
--- a/modules/core/test/ocl/test_arithm.cpp
+++ b/modules/core/test/ocl/test_arithm.cpp
@@ -1355,7 +1355,7 @@ OCL_TEST_P(ScaleAdd, Mat)
         OCL_OFF(cv::scaleAdd(src1_roi, val[0], src2_roi, dst1_roi));
         OCL_ON(cv::scaleAdd(usrc1_roi, val[0], usrc2_roi, udst1_roi));
 
-        Near(depth <= CV_32S ? 1 : 1e-6);
+        Near(depth <= CV_32S ? 1 : 1e-3);
     }
 }