zephyr: drivers: Add test for uart host commands

Test CONSOLE_READ and CONSOLE_SNAPSHOT host commands if correct content
of buffer is returned in read next and read recent variants.

BUG=b:229935172
BRANCH=none
TEST=zmake -D test test-drivers

Signed-off-by: Tomasz Michalec <tm@semihalf.com>
Change-Id: I90af94c0851fc7311236beeba8108e36e53c49c4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3310859
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Tomasz Michalec <tmichalec@google.com>
Tested-by: Tomasz Michalec <tmichalec@google.com>

2 files changed, 232 insertions, 0 deletions

diff --git a/zephyr/test/drivers/CMakeLists.txt b/zephyr/test/drivers/CMakeLists.txt
index a762365475..f919a45788 100644
--- a/zephyr/test/drivers/CMakeLists.txt
+++ b/zephyr/test/drivers/CMakeLists.txt
@@ -63,6 +63,7 @@ target_sources(app PRIVATE
   src/test_mocks.c
   src/test_rules.c
   src/thermistor.c
+  src/uart_hostcmd.c
   src/usb_mux.c
   src/usb_pd_host_cmd.c
   src/utils.c
diff --git a/zephyr/test/drivers/src/uart_hostcmd.c b/zephyr/test/drivers/src/uart_hostcmd.c
new file mode 100644
index 0000000000..82533639a5
--- /dev/null
+++ b/zephyr/test/drivers/src/uart_hostcmd.c
@@ -0,0 +1,231 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <zephyr.h>
+#include <ztest.h>
+
+#include "console.h"
+#include "host_command.h"
+#include "uart.h"
+#include "test/drivers/test_state.h"
+
+/** Messages used in test */
+static const char msg1[] = "test";
+static const char msg2[] = "uart_hostcmd";
+static const char msg3[] = "message3";
+
+/** Length of message excluding NULL char at the end */
+#define MSG_LEN(msg) (sizeof(msg) - 1)
+
+/**
+ * Write message 1 before first snapshot. Read everything from buffer. Create
+ * second snapshot. Write message 2 after it.
+ */
+static void setup_snapshots_and_messages(void *unused)
+{
+	char response[1024];
+	struct host_cmd_handler_args read_args =
+		BUILD_HOST_COMMAND_RESPONSE(EC_CMD_CONSOLE_READ, 0, response);
+	struct host_cmd_handler_args args =
+		BUILD_HOST_COMMAND_SIMPLE(EC_CMD_CONSOLE_SNAPSHOT, 0);
+
+	/* Set first snapshot before first message */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&args), NULL);
+	cputs(CC_COMMAND, msg1);
+
+	/* Read everything from buffer */
+	do {
+		/* Clear response size before executing command */
+		read_args.response_size = 0;
+		zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args),
+			      NULL);
+	} while (read_args.response_size != 0);
+
+	/* Set second snapshot after first message */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&args), NULL);
+	cputs(CC_COMMAND, msg2);
+}
+
+/**
+ * Test if read next variant of console read host command is working. ver
+ * argument allows to change version of command. In case of version 1, parameter
+ * with sub command is provided.
+ */
+static void test_uart_hc_read_next(int ver)
+{
+	/* Should be able to read whole buffer in one command */
+	char response[CONFIG_PLATFORM_EC_HOSTCMD_CONSOLE_BUF_SIZE + 1];
+	struct ec_params_console_read_v1 params;
+	struct host_cmd_handler_args read_args =
+		BUILD_HOST_COMMAND_RESPONSE(EC_CMD_CONSOLE_READ, ver, response);
+	struct host_cmd_handler_args snap_args =
+		BUILD_HOST_COMMAND_SIMPLE(EC_CMD_CONSOLE_SNAPSHOT, 0);
+	char *msg1_start;
+	char *msg2_start;
+	char *msg3_start;
+
+	/* Set up host command parameters */
+	if (ver == 1) {
+		read_args.params = &params;
+		read_args.params_size = sizeof(params);
+		params.subcmd = CONSOLE_READ_NEXT;
+	}
+
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+
+	/*
+	 * Whole buffer until snapshot should be in response, check if it ends
+	 * with message 1 which should start at the end of response excluding
+	 * NULL char.
+	 */
+	msg1_start = response + read_args.response_size - 1 - MSG_LEN(msg1);
+	zassert_mem_equal(msg1, msg1_start, MSG_LEN(msg1),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg1, MSG_LEN(msg1), msg1_start);
+
+	/* Set new snapshot which should include message 2 */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&snap_args), NULL);
+
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+
+	/*
+	 * Whole buffer should be in response, check if it ends with both
+	 * messages. Message 2 should start at the end of response excluding
+	 * NULL char.
+	 */
+	msg2_start = response + read_args.response_size - 1 - MSG_LEN(msg2);
+	msg1_start = msg2_start - MSG_LEN(msg1);
+	zassert_mem_equal(msg2, msg2_start, MSG_LEN(msg2),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg2, MSG_LEN(msg2), msg2_start);
+	zassert_mem_equal(msg1, msg1_start, MSG_LEN(msg1),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg1, MSG_LEN(msg1), msg1_start);
+
+	/* Append third message */
+	cputs(CC_COMMAND, msg3);
+
+	/* Check read next without new snapshot, no data should be read */
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal(0, read_args.response_size,
+		      "expected message length 0, got %d",
+		      read_args.response_size);
+
+	/* Set new snapshot which should include message 3 */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&snap_args), NULL);
+
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+
+	msg3_start = response + read_args.response_size - 1 - MSG_LEN(msg3);
+	msg2_start = msg3_start - MSG_LEN(msg2);
+	msg1_start = msg2_start - MSG_LEN(msg1);
+	zassert_mem_equal(msg3, msg3_start, MSG_LEN(msg3),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg3, MSG_LEN(msg3), msg3_start);
+	zassert_mem_equal(msg2, msg2_start, MSG_LEN(msg2),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg2, MSG_LEN(msg2), msg2_start);
+	zassert_mem_equal(msg1, msg1_start, MSG_LEN(msg1),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg1, MSG_LEN(msg1), msg1_start);
+}
+
+ZTEST_USER(uart_hostcmd, test_uart_hc_read_next_v0)
+{
+	test_uart_hc_read_next(0);
+}
+
+ZTEST_USER(uart_hostcmd, test_uart_hc_read_next_v1)
+{
+	test_uart_hc_read_next(1);
+}
+
+/** Test if read recent variant of console read host command is working */
+ZTEST_USER(uart_hostcmd, test_uart_hc_read_recent_v1)
+{
+	/* Should be able to read whole buffer in one command */
+	char response[CONFIG_PLATFORM_EC_HOSTCMD_CONSOLE_BUF_SIZE + 1];
+	struct ec_params_console_read_v1 params;
+	struct host_cmd_handler_args read_args =
+		BUILD_HOST_COMMAND(EC_CMD_CONSOLE_READ, 1, response, params);
+	struct host_cmd_handler_args snap_args =
+		BUILD_HOST_COMMAND_SIMPLE(EC_CMD_CONSOLE_SNAPSHOT, 0);
+
+	params.subcmd = CONSOLE_READ_RECENT;
+
+	/* Only message 1 which is between two last snapshots should be read */
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+	/* Account additional NULL char at the end */
+	zassert_equal(MSG_LEN(msg1) + 1, read_args.response_size,
+		      "expected message length %d, got %d",
+		      MSG_LEN(msg1) + 1, read_args.response_size);
+	zassert_mem_equal(msg1, response, MSG_LEN(msg1),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg1, MSG_LEN(msg1), response);
+
+	/* Set new snapshot after second message */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&snap_args), NULL);
+
+	/* Only message between two last snapshots should be read */
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+	/* Account additional NULL char at the end */
+	zassert_equal(MSG_LEN(msg2) + 1, read_args.response_size,
+		      "expected message length %d, got %d",
+		      MSG_LEN(msg2) + 1, read_args.response_size);
+	zassert_mem_equal(msg2, response, MSG_LEN(msg2),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg2, MSG_LEN(msg2), response);
+
+	/* Append third message */
+	cputs(CC_COMMAND, msg3);
+
+	/* Check that message is not read without setting snapshot */
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal(0, read_args.response_size,
+		      "expected message length 0, got %d",
+		      read_args.response_size);
+
+	/* Set new snapshot */
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&snap_args), NULL);
+
+	/* This time only third message should be read */
+	read_args.response_size = 0;
+	zassert_equal(EC_RES_SUCCESS, host_command_process(&read_args), NULL);
+	zassert_equal('\0', response[read_args.response_size],
+		      "Last byte of response is not '\\0' (got 0x%x)",
+		      response[read_args.response_size]);
+	/* Account additional NULL char at the end */
+	zassert_equal(MSG_LEN(msg3) + 1, read_args.response_size,
+		      "expected message length %d, got %d",
+		      MSG_LEN(msg3) + 1, read_args.response_size);
+	zassert_mem_equal(msg3, response, MSG_LEN(msg3),
+			  "expected \"%s\", got \"%.*s\"",
+			  msg3, MSG_LEN(msg3), response);
+}
+
+ZTEST_SUITE(uart_hostcmd, drivers_predicate_post_main, NULL,
+	    setup_snapshots_and_messages, NULL, NULL);