regmap: kunit: Add cache-drop test with multiple cache blocks

Add a test case for dropping only some cache blocks and leaving others
unchanged.

The regmap is divided into 8 register ranges, and only 4 of these are
written with values. This creates 4 non-contiguous ranges of registers
with cached values.

One whole range is then dropped, and part of another range. A cache
sync is then performed to check that the correct registers were written,
and the correct values were written to these registers.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://msgid.link/r/20240408144600.230848-11-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: rfvirgil

drivers/base/regmap/regmap-kunit.c

@@ -1007,6 +1007,108 @@ static void cache_drop(struct kunit *test)
 	KUNIT_EXPECT_MEMEQ(test, &data->vals[param->from_reg], rval, sizeof(rval));
 }
 
+static void cache_drop_with_non_contiguous_ranges(struct kunit *test)
+{
+	const struct regmap_test_param *param = test->param_value;
+	struct regmap *map;
+	struct regmap_config config;
+	struct regmap_ram_data *data;
+	unsigned int val[4][BLOCK_TEST_SIZE];
+	unsigned int reg;
+	const int num_ranges = ARRAY_SIZE(val) * 2;
+	int rangeidx, i;
+
+	static_assert(ARRAY_SIZE(val) == 4);
+
+	config = test_regmap_config;
+	config.max_register = param->from_reg + (num_ranges * BLOCK_TEST_SIZE);
+
+	map = gen_regmap(test, &config, &data);
+	KUNIT_ASSERT_FALSE(test, IS_ERR(map));
+	if (IS_ERR(map))
+		return;
+
+	for (i = 0; i < config.max_register + 1; i++)
+		data->written[i] = false;
+
+	/* Create non-contiguous cache blocks by writing every other range */
+	get_random_bytes(&val, sizeof(val));
+	for (rangeidx = 0; rangeidx < num_ranges; rangeidx += 2) {
+		reg = param->from_reg + (rangeidx * BLOCK_TEST_SIZE);
+		KUNIT_EXPECT_EQ(test, 0, regmap_bulk_write(map, reg,
+							   &val[rangeidx / 2],
+							   BLOCK_TEST_SIZE));
+		KUNIT_EXPECT_MEMEQ(test, &data->vals[reg],
+				   &val[rangeidx / 2], sizeof(val[rangeidx / 2]));
+	}
+
+	/* Check that odd ranges weren't written */
+	for (rangeidx = 1; rangeidx < num_ranges; rangeidx += 2) {
+		reg = param->from_reg + (rangeidx * BLOCK_TEST_SIZE);
+		for (i = 0; i < BLOCK_TEST_SIZE; i++)
+			KUNIT_EXPECT_FALSE(test, data->written[reg + i]);
+	}
+
+	/* Drop range 2 */
+	reg = param->from_reg + (2 * BLOCK_TEST_SIZE);
+	KUNIT_EXPECT_EQ(test, 0, regcache_drop_region(map, reg, reg + BLOCK_TEST_SIZE - 1));
+
+	/* Drop part of range 4 */
+	reg = param->from_reg + (4 * BLOCK_TEST_SIZE);
+	KUNIT_EXPECT_EQ(test, 0, regcache_drop_region(map, reg + 3, reg + 5));
+
+	/* Mark dirty and reset mock registers to 0 */
+	regcache_mark_dirty(map);
+	for (i = 0; i < config.max_register + 1; i++) {
+		data->vals[i] = 0;
+		data->written[i] = false;
+	}
+
+	/* The registers that were dropped from range 4 should now remain at 0 */
+	val[4 / 2][3] = 0;
+	val[4 / 2][4] = 0;
+	val[4 / 2][5] = 0;
+
+	/* Sync and check that the expected register ranges were written */
+	KUNIT_EXPECT_EQ(test, 0, regcache_sync(map));
+
+	/* Check that odd ranges weren't written */
+	for (rangeidx = 1; rangeidx < num_ranges; rangeidx += 2) {
+		reg = param->from_reg + (rangeidx * BLOCK_TEST_SIZE);
+		for (i = 0; i < BLOCK_TEST_SIZE; i++)
+			KUNIT_EXPECT_FALSE(test, data->written[reg + i]);
+	}
+
+	/* Check that even ranges (except 2 and 4) were written */
+	for (rangeidx = 0; rangeidx < num_ranges; rangeidx += 2) {
+		if ((rangeidx == 2) || (rangeidx == 4))
+			continue;
+
+		reg = param->from_reg + (rangeidx * BLOCK_TEST_SIZE);
+		for (i = 0; i < BLOCK_TEST_SIZE; i++)
+			KUNIT_EXPECT_TRUE(test, data->written[reg + i]);
+
+		KUNIT_EXPECT_MEMEQ(test, &data->vals[reg],
+				   &val[rangeidx / 2], sizeof(val[rangeidx / 2]));
+	}
+
+	/* Check that range 2 wasn't written */
+	reg = param->from_reg + (2 * BLOCK_TEST_SIZE);
+	for (i = 0; i < BLOCK_TEST_SIZE; i++)
+		KUNIT_EXPECT_FALSE(test, data->written[reg + i]);
+
+	/* Check that range 4 was partially written */
+	reg = param->from_reg + (4 * BLOCK_TEST_SIZE);
+	for (i = 0; i < BLOCK_TEST_SIZE; i++)
+		KUNIT_EXPECT_EQ(test, data->written[reg + i], i < 3 || i > 5);
+
+	KUNIT_EXPECT_MEMEQ(test, &data->vals[reg], &val[4 / 2], sizeof(val[4 / 2]));
+
+	/* Nothing before param->from_reg should have been written */
+	for (i = 0; i < param->from_reg; i++)
+		KUNIT_EXPECT_FALSE(test, data->written[i]);
+}
+
 static void cache_drop_all_and_sync_marked_dirty(struct kunit *test)
 {
 	const struct regmap_test_param *param = test->param_value;
@@ -1663,6 +1765,7 @@ static struct kunit_case regmap_test_cases[] = {
 	KUNIT_CASE_PARAM(cache_sync_readonly, real_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_sync_patch, real_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop, sparse_cache_types_gen_params),
+	KUNIT_CASE_PARAM(cache_drop_with_non_contiguous_ranges, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_all_and_sync_marked_dirty, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_all_and_sync_no_defaults, sparse_cache_types_gen_params),
 	KUNIT_CASE_PARAM(cache_drop_all_and_sync_has_defaults, sparse_cache_types_gen_params),