test: dm: tee: extend with RPC test

Extend existing DM tee tests adding test coverage for reverse RPC calls.
Currently this commit only adds tests for I2C requests from TEE driver
to TEE supplicant, for instance reading/writing data to emulated i2c
eeprom defines in standard sandbox test device tree
(arch/sandbox/dts/test.dtb):

=> i2c bus
Bus 0:	i2c@0  (active 0)
   2c: eeprom@2c, offset len 1, flags 0
   ...

Running TEE tests:
=> ut dm tee
Test: dm_test_tee: tee.c
Test: dm_test_tee: tee.c (flat tree)
Failures: 0

Signed-off-by: Igor Opaniuk <igor.opaniuk@foundries.io>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Etienne Carriere <etienne.carriere@linaro.org>

test/dm/tee.c

@@ -13,15 +13,16 @@
 #include <test/test.h>
 #include <test/ut.h>
 #include <tee/optee_ta_avb.h>
+#include <tee/optee_ta_rpc_test.h>
 
-static int open_session(struct udevice *dev, u32 *session)
+static int open_session(struct udevice *dev, u32 *session,
+			struct tee_optee_ta_uuid *uuid)
 {
 	struct tee_open_session_arg arg;
-	const struct tee_optee_ta_uuid uuid = TA_AVB_UUID;
 	int rc;
 
 	memset(&arg, 0, sizeof(arg));
-	tee_optee_ta_uuid_to_octets(arg.uuid, &uuid);
+	tee_optee_ta_uuid_to_octets(arg.uuid, uuid);
 	rc = tee_open_session(dev, &arg, 0, NULL);
 	if (rc)
 		return rc;
@@ -32,7 +33,7 @@ static int open_session(struct udevice *dev, u32 *session)
 	return 0;
 }
 
-static int invoke_func(struct udevice *dev, u32 session)
+static int invoke_func_avb(struct udevice *dev, u32 session)
 {
 	struct tee_param param = { .attr = TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT };
 	struct tee_invoke_arg arg;
@@ -47,6 +48,48 @@ static int invoke_func(struct udevice *dev, u32 session)
 	return 0;
 }
 
+static int invoke_func_rpc_test(struct udevice *dev, u32 session,
+				u64 op, u64 busnum, u64 chip_addr,
+				u64 xfer_flags, u8 *buf, size_t buf_size)
+{
+	struct tee_param param[2];
+	struct tee_invoke_arg arg;
+	struct tee_shm *shm_buf;
+	int rc;
+
+	memset(&arg, 0, sizeof(arg));
+	arg.session = session;
+	arg.func = op;
+
+	rc = tee_shm_alloc(dev, buf_size,
+			   TEE_SHM_ALLOC, &shm_buf);
+	if (rc)
+		return rc;
+
+	if (op == TA_RPC_TEST_CMD_I2C_WRITE)
+		memcpy(shm_buf->addr, buf, buf_size);
+
+	memset(param, 0, sizeof(param));
+	param[0].attr = TEE_PARAM_ATTR_TYPE_VALUE_INPUT;
+	param[0].u.value.a = busnum;
+	param[0].u.value.b = chip_addr;
+	param[0].u.value.c = xfer_flags;
+	param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INOUT;
+	param[1].u.memref.shm = shm_buf;
+	param[1].u.memref.size = buf_size;
+
+	if (tee_invoke_func(dev, &arg, 2, param) || arg.ret) {
+		rc = -1;
+		goto out;
+	}
+
+	if (op == TA_RPC_TEST_CMD_I2C_READ)
+		memcpy(buf, shm_buf->addr, buf_size);
+out:
+	tee_shm_free(shm_buf);
+	return rc;
+}
+
 static int match(struct tee_version_data *vers, const void *data)
 {
 	return vers->gen_caps & TEE_GEN_CAP_GP;
@@ -62,6 +105,7 @@ static int test_tee(struct unit_test_state *uts, struct test_tee_vars *vars)
 	struct tee_version_data vers;
 	struct udevice *dev;
 	struct sandbox_tee_state *state;
+	struct tee_optee_ta_uuid avb_uuid = TA_AVB_UUID;
 	u32 session = 0;
 	int rc;
 	u8 data[128];
@@ -71,11 +115,11 @@ static int test_tee(struct unit_test_state *uts, struct test_tee_vars *vars)
 	state = dev_get_priv(dev);
 	ut_assert(!state->session);
 
-	rc = open_session(dev, &session);
+	rc = open_session(dev, &session, &avb_uuid);
 	ut_assert(!rc);
 	ut_assert(session == state->session);
 
-	rc = invoke_func(dev, session);
+	rc = invoke_func_avb(dev, session);
 	ut_assert(!rc);
 
 	rc = tee_close_session(dev, session);
@@ -100,7 +144,59 @@ static int test_tee(struct unit_test_state *uts, struct test_tee_vars *vars)
 	vars->alloc_shm = NULL;
 	ut_assert(!state->num_shms);
 
-	return 0;
+	return rc;
+}
+
+#define I2C_BUF_SIZE 64
+
+static int test_tee_rpc(struct unit_test_state *uts)
+{
+	struct tee_version_data vers;
+	struct udevice *dev;
+	struct sandbox_tee_state *state;
+	struct tee_optee_ta_uuid rpc_test_uuid = TA_RPC_TEST_UUID;
+	u32 session = 0;
+	int rc;
+
+	char *test_str = "Test string";
+	u8 data[I2C_BUF_SIZE] = {0};
+	u8 data_from_eeprom[I2C_BUF_SIZE] = {0};
+
+	/* Use sandbox I2C EEPROM emulation; bus: 0, chip: 0x2c */
+	u64 bus = 0;
+	u64 chip = 0x2c;
+	u64 xfer_flags = 0;
+
+	dev = tee_find_device(NULL, match, NULL, &vers);
+	ut_assert(dev);
+	state = dev_get_priv(dev);
+	ut_assert(!state->session);
+
+	/* Test RPC call asking for I2C service */
+	rc = open_session(dev, &session, &rpc_test_uuid);
+	ut_assert(!rc);
+	ut_assert(session == state->session);
+
+	/* Write buffer */
+	strncpy((char *)data, test_str, strlen(test_str));
+	rc = invoke_func_rpc_test(dev, session, TA_RPC_TEST_CMD_I2C_WRITE,
+				  bus, chip, xfer_flags, data, sizeof(data));
+	ut_assert(!rc);
+
+	/* Read buffer */
+	rc = invoke_func_rpc_test(dev, session, TA_RPC_TEST_CMD_I2C_READ,
+				  bus, chip, xfer_flags, data_from_eeprom,
+				  sizeof(data_from_eeprom));
+	ut_assert(!rc);
+
+	/* Compare */
+	ut_assert(!memcmp(data, data_from_eeprom, sizeof(data)));
+
+	rc = tee_close_session(dev, session);
+	ut_assert(!rc);
+	ut_assert(!state->session);
+
+	return rc;
 }
 
 static int dm_test_tee(struct unit_test_state *uts)
@@ -108,6 +204,12 @@ static int dm_test_tee(struct unit_test_state *uts)
 	struct test_tee_vars vars = { NULL, NULL };
 	int rc = test_tee(uts, &vars);
 
+	if (rc)
+		goto out;
+
+	if (IS_ENABLED(CONFIG_OPTEE_TA_RPC_TEST))
+		rc = test_tee_rpc(uts);
+out:
 	/* In case test_tee() asserts these may still remain allocated */
 	tee_shm_free(vars.reg_shm);
 	tee_shm_free(vars.alloc_shm);