tf-psa-crypto: cmake: Add lcov target

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/tf-psa-crypto/TF-PSA-Crypto.cmake b/tf-psa-crypto/TF-PSA-Crypto.cmake
index 3925150..b96dab2 100644
--- a/tf-psa-crypto/TF-PSA-Crypto.cmake
+++ b/tf-psa-crypto/TF-PSA-Crypto.cmake
@@ -367,6 +367,17 @@
 
     # additional convenience targets for Unix only
     if(UNIX)
+        # For coverage testing:
+        # 1. Build with:
+        #         cmake -D CMAKE_BUILD_TYPE=Coverage /path/to/source && make
+        # 2. Run the relevant tests for the part of the code you're interested in.
+        #    For the reference coverage measurement, see
+        #    tests/scripts/basic-build-test.sh
+        # 3. Run scripts/lcov.sh to generate an HTML report.
+        ADD_CUSTOM_TARGET(lcov
+            COMMAND ${MBEDTLS_DIR}/scripts/lcov.sh
+        )
+
         ADD_CUSTOM_TARGET(memcheck
             COMMAND sed -i.bak s+/usr/bin/valgrind+`which valgrind`+ DartConfiguration.tcl
             COMMAND ctest -O memcheck.log -D ExperimentalMemCheck
diff --git a/tf-psa-crypto/tests/CMakeLists.txt b/tf-psa-crypto/tests/CMakeLists.txt
index 4755cae..0e84bab 100644
--- a/tf-psa-crypto/tests/CMakeLists.txt
+++ b/tf-psa-crypto/tests/CMakeLists.txt
@@ -350,5 +350,6 @@
     if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/seedfile")
         link_to_source(seedfile)
     endif()
+    link_to_source(Descriptions.txt)
     link_to_source(../../framework/data_files)
 endif()
diff --git a/tf-psa-crypto/tests/Descriptions.txt b/tf-psa-crypto/tests/Descriptions.txt
new file mode 100644
index 0000000..bc25056
--- /dev/null
+++ b/tf-psa-crypto/tests/Descriptions.txt
@@ -0,0 +1,5 @@
+test_suites
+    The various 'test_suite_XXX' programs from the 'tests' directory, executed
+    using 'make check' (Unix make) or 'make test' (Cmake), include test cases
+    (reference test vectors, sanity checks, malformed input for parsing
+    functions, etc.) for all modules except the SSL modules.