From 180033061e203a7c5510e7c38bccd885657de517 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 13 Jun 2023 21:17:42 +0100 Subject: [PATCH 1/3] regmap: Add test that writes to write only registers are prevented We should have error checking that verifies that writes to write only registers are suppressed, verify that this happens as it should. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230613-regmap-kunit-read-write-v1-1-2db337c52827@kernel.org Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-kunit.c | 41 ++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c index 4ec5cbfc0ca0..f5c175022a47 100644 --- a/drivers/base/regmap/regmap-kunit.c +++ b/drivers/base/regmap/regmap-kunit.c @@ -92,6 +92,11 @@ static struct regmap *gen_regmap(struct regmap_config *config, return ret; } +static bool reg_5_false(struct device *context, unsigned int reg) +{ + return reg != 5; +} + static void basic_read_write(struct kunit *test) { struct regcache_types *t = (struct regcache_types *)test->param_value; @@ -191,6 +196,41 @@ static void bulk_read(struct kunit *test) regmap_exit(map); } +static void write_readonly(struct kunit *test) +{ + struct regcache_types *t = (struct regcache_types *)test->param_value; + struct regmap *map; + struct regmap_config config; + struct regmap_ram_data *data; + unsigned int val; + int i; + + config = test_regmap_config; + config.cache_type = t->type; + config.num_reg_defaults = BLOCK_TEST_SIZE; + config.writeable_reg = reg_5_false; + + map = gen_regmap(&config, &data); + KUNIT_ASSERT_FALSE(test, IS_ERR(map)); + if (IS_ERR(map)) + return; + + get_random_bytes(&val, sizeof(val)); + + for (i = 0; i < BLOCK_TEST_SIZE; i++) + data->written[i] = false; + + /* Change the value of all registers, readonly should fail */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, i != 5, regmap_write(map, i, val) == 0); + + /* Did that match what we see on the device? */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, i != 5, data->written[i]); + + regmap_exit(map); +} + static void reg_defaults(struct kunit *test) { struct regcache_types *t = (struct regcache_types *)test->param_value; @@ -1037,6 +1077,7 @@ static struct kunit_case regmap_test_cases[] = { KUNIT_CASE_PARAM(basic_read_write, regcache_types_gen_params), KUNIT_CASE_PARAM(bulk_write, regcache_types_gen_params), KUNIT_CASE_PARAM(bulk_read, regcache_types_gen_params), + KUNIT_CASE_PARAM(write_readonly, regcache_types_gen_params), KUNIT_CASE_PARAM(reg_defaults, regcache_types_gen_params), KUNIT_CASE_PARAM(reg_defaults_read_dev, regcache_types_gen_params), KUNIT_CASE_PARAM(register_patch, regcache_types_gen_params), From a07bff4054c9e2b3a5c5790312a4a45aaeca7afe Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 13 Jun 2023 21:17:43 +0100 Subject: [PATCH 2/3] regmap: Add a test case for write only registers Validate that attempts to read from write only registers fail and don't somehow trigger spurious hardware accesses. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230613-regmap-kunit-read-write-v1-2-2db337c52827@kernel.org Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-kunit.c | 32 ++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c index f5c175022a47..a1a1a9ce2e13 100644 --- a/drivers/base/regmap/regmap-kunit.c +++ b/drivers/base/regmap/regmap-kunit.c @@ -231,6 +231,37 @@ static void write_readonly(struct kunit *test) regmap_exit(map); } +static void read_writeonly(struct kunit *test) +{ + struct regcache_types *t = (struct regcache_types *)test->param_value; + struct regmap *map; + struct regmap_config config; + struct regmap_ram_data *data; + unsigned int val; + int i; + + config = test_regmap_config; + config.cache_type = t->type; + config.readable_reg = reg_5_false; + + map = gen_regmap(&config, &data); + KUNIT_ASSERT_FALSE(test, IS_ERR(map)); + if (IS_ERR(map)) + return; + + for (i = 0; i < BLOCK_TEST_SIZE; i++) + data->read[i] = false; + + /* Try to read all the registers, the writeonly one should fail */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, i != 5, regmap_read(map, i, &val) == 0); + + /* Did we trigger a hardware access? */ + KUNIT_EXPECT_FALSE(test, data->read[5]); + + regmap_exit(map); +} + static void reg_defaults(struct kunit *test) { struct regcache_types *t = (struct regcache_types *)test->param_value; @@ -1078,6 +1109,7 @@ static struct kunit_case regmap_test_cases[] = { KUNIT_CASE_PARAM(bulk_write, regcache_types_gen_params), KUNIT_CASE_PARAM(bulk_read, regcache_types_gen_params), KUNIT_CASE_PARAM(write_readonly, regcache_types_gen_params), + KUNIT_CASE_PARAM(read_writeonly, regcache_types_gen_params), KUNIT_CASE_PARAM(reg_defaults, regcache_types_gen_params), KUNIT_CASE_PARAM(reg_defaults_read_dev, regcache_types_gen_params), KUNIT_CASE_PARAM(register_patch, regcache_types_gen_params), From 357a1ebd0c012f5421252547ebf4ee619b45733d Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 13 Jun 2023 21:17:44 +0100 Subject: [PATCH 3/3] regmap: Add test to make sure we don't sync to read only registers Ensure that a read only value in the register cache does not result in a write during regcache_sync(). Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230613-regmap-kunit-read-write-v1-3-2db337c52827@kernel.org Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-kunit.c | 42 ++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c index a1a1a9ce2e13..6f444ac0ec49 100644 --- a/drivers/base/regmap/regmap-kunit.c +++ b/drivers/base/regmap/regmap-kunit.c @@ -680,6 +680,47 @@ static void cache_sync_defaults(struct kunit *test) regmap_exit(map); } +static void cache_sync_readonly(struct kunit *test) +{ + struct regcache_types *t = (struct regcache_types *)test->param_value; + struct regmap *map; + struct regmap_config config; + struct regmap_ram_data *data; + unsigned int val; + int i; + + config = test_regmap_config; + config.cache_type = t->type; + config.writeable_reg = reg_5_false; + + map = gen_regmap(&config, &data); + KUNIT_ASSERT_FALSE(test, IS_ERR(map)); + if (IS_ERR(map)) + return; + + /* Read all registers to fill the cache */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, 0, regmap_read(map, i, &val)); + + /* Change the value of all registers, readonly should fail */ + get_random_bytes(&val, sizeof(val)); + regcache_cache_only(map, true); + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, i != 5, regmap_write(map, i, val) == 0); + regcache_cache_only(map, false); + + /* Resync */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + data->written[i] = false; + KUNIT_EXPECT_EQ(test, 0, regcache_sync(map)); + + /* Did that match what we see on the device? */ + for (i = 0; i < BLOCK_TEST_SIZE; i++) + KUNIT_EXPECT_EQ(test, i != 5, data->written[i]); + + regmap_exit(map); +} + static void cache_sync_patch(struct kunit *test) { struct regcache_types *t = (struct regcache_types *)test->param_value; @@ -1119,6 +1160,7 @@ static struct kunit_case regmap_test_cases[] = { KUNIT_CASE_PARAM(cache_bypass, real_cache_types_gen_params), KUNIT_CASE_PARAM(cache_sync, real_cache_types_gen_params), KUNIT_CASE_PARAM(cache_sync_defaults, real_cache_types_gen_params), + 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),