tests: Add test region and symbol macros to <tests/test.h>

Some modules require and operate on memory regions and symbols.
This macros systematize how they are defined in testing code.

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: I314028c201732416bb3d5446a4c8585e055073e3
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46684
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>

tests/include/tests/test.h

@@ -14,4 +14,18 @@
 #include <setjmp.h>
 #include <cmocka.h>
 
+/*
+ * Set symbol value and make it global.
+ */
+#define TEST_SYMBOL(symbol, address) asm(".set " #symbol ", " #address "\n\t.globl " #symbol)
+
+/*
+ * Define memory region for testing purpose.
+ *
+ * Create buffer with specified name and size.
+ * Create end symbol for it.
+ */
+#define TEST_REGION(region, size) uint8_t _##region[size]; \
+	TEST_SYMBOL(_e##region, _##region + size)
+
 #endif /* _TESTS_TEST_H */