tests: kernel: cache: Add test for __dcacheline_aligned/unique

Add test which checks that variable tagged with __dcacheline_aligned is correctly aligned, and that the variables tagged with __dcacheline_unique are in the proper section that gives a unique data cache line for each. Co-authored-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no> Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no> Signed-off-by: Abderrahmane JARMOUNI <git@jarmouni.me>

Author: JarmouniA

tests/kernel/cache/src/test_cache_api.c

@@ -79,6 +79,53 @@ ZTEST_USER(cache_api, test_data_cache_api_user)
 zassert_true((ret == 0) || (ret == -ENOTSUP));
 }
 
+#ifdef CONFIG_DCACHE_LINE_SIZE
+ZTEST(cache_api, test_dcacheline_aligned_unique)
+{
+static uint8_t var1 __dcacheline_unique;
+static uint8_t var2[5] __dcacheline_unique;
+
+static uint8_t var3 __dcacheline_unique;
+
+static uint8_t var4 __dcacheline_aligned;
+static uint8_t var5[5] __dcacheline_aligned;
+
+static uint8_t var6 __dcacheline_aligned;
+extern uintptr_t __data_cache_start;
+extern uintptr_t __data_cache_end;
+
+zassert_true(IS_ALIGNED(&var1, CONFIG_DCACHE_LINE_SIZE));
+zassert_true(IS_ALIGNED(var2, CONFIG_DCACHE_LINE_SIZE));
+zassert_true(IS_ALIGNED(&var3, CONFIG_DCACHE_LINE_SIZE));
+zassert_true(IS_ALIGNED(&var4, CONFIG_DCACHE_LINE_SIZE));
+zassert_true(IS_ALIGNED(var5, CONFIG_DCACHE_LINE_SIZE));
+zassert_true(IS_ALIGNED(&var6, CONFIG_DCACHE_LINE_SIZE));
+
+/* Validate that variables are placed in the dedicated section
+ * that gives a unique data cache line for each.
+ */
+zassert_between_inclusive((uintptr_t)&var1, (uintptr_t)&__data_cache_start,
+ (uintptr_t)&__data_cache_end);
+zassert_between_inclusive((uintptr_t)var2, (uintptr_t)&__data_cache_start,
+ (uintptr_t)&__data_cache_end);
+zassert_between_inclusive((uintptr_t)&var3, (uintptr_t)&__data_cache_start,
+ (uintptr_t)&__data_cache_end);
+
+var1 = 1;
+var2[0] = 2;
+var3 = 3;
+var4 = 4;
+var5[0] = 5;
+var6 = 6;
+zassert_equal(var1, 1);
+zassert_equal(var2[0], 2);
+zassert_equal(var3, 3);
+zassert_equal(var4, 4);
+zassert_equal(var5[0], 5);
+zassert_equal(var6, 6);
+}
+#endif
+
 static void *cache_api_setup(void)
 {
 sys_cache_data_enable();