kconfig: add CONFIG_CC_COVERAGE

Make it possible to use gcc code coverage analysis.

v1 -> v2:
 - Kconfig: remove not needed 'default n'
 - Makefile: use consistent spacing

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/.gitignore b/.gitignore
index 29757aa..f1b8015 100644
--- a/.gitignore
+++ b/.gitignore
@@ -85,3 +85,7 @@
 *.orig
 *~
 \#*#
+
+# gcc code coverage files
+*.gcda
+*.gcno
diff --git a/Kconfig b/Kconfig
index 6670913..67b8c50 100644
--- a/Kconfig
+++ b/Kconfig
@@ -59,6 +59,13 @@
 
 	  This option is enabled by default for U-Boot.
 
+config CC_COVERAGE
+	bool "Enable code coverage analysis"
+	depends on SANDBOX
+	help
+	  Enabling this option will pass "--coverage" to gcc to compile
+	  and link code instrumented for coverage analysis.
+
 config DISTRO_DEFAULTS
 	bool "Select defaults suitable for booting general purpose Linux distributions"
 	default y if ARCH_SUNXI || TEGRA
diff --git a/Makefile b/Makefile
index bfe115c..9eb7e5b 100644
--- a/Makefile
+++ b/Makefile
@@ -725,6 +725,12 @@
 PLATFORM_LIBGCC := -L $(shell dirname `$(CC) $(c_flags) -print-libgcc-file-name`) -lgcc
 endif
 PLATFORM_LIBS += $(PLATFORM_LIBGCC)
+
+ifdef CONFIG_CC_COVERAGE
+KBUILD_CFLAGS += --coverage
+PLATFORM_LIBGCC += -lgcov
+endif
+
 export PLATFORM_LIBS
 export PLATFORM_LIBGCC