[nrf fromtree] tests: drivers: uart: async_api: Make long buffer configurable

One of the test case is performing long transfers using 1k buffers.
For some targets there may be not enough RAM to perform such
transfers. Make long buffer length configurable.

Signed-off-by: Krzysztof Chruściński <[email protected]>
(cherry picked from commit d612982)

Author: nordic-krch

tests/drivers/uart/uart_async_api/Kconfig

@@ -19,3 +19,7 @@ config DT_DEFINED_NOCACHE_NAME
 endif # DT_DEFINED_NOCACHE
 
 endif # DCACHE
+
+config TEST_LONG_BUFFER_SIZE
+	int "Long buffer size"
+	default 1024

tests/drivers/uart/uart_async_api/src/test_uart_async.c

@@ -850,14 +850,17 @@ ZTEST_USER(uart_async_chain_write, test_chained_write)
 		      "RX_DISABLED timeout");
 }
 
+#define RX_LONG_BUFFER CONFIG_TEST_LONG_BUFFER_SIZE
+#define TX_LONG_BUFFER (CONFIG_TEST_LONG_BUFFER_SIZE - 8)
+
 #if NOCACHE_MEM
-static __aligned(32) uint8_t long_rx_buf[1024] __used __NOCACHE;
-static __aligned(32) uint8_t long_rx_buf2[1024] __used __NOCACHE;
-static __aligned(32) uint8_t long_tx_buf[1000] __used __NOCACHE;
+static __aligned(32) uint8_t long_rx_buf[RX_LONG_BUFFER] __used __NOCACHE;
+static __aligned(32) uint8_t long_rx_buf2[RX_LONG_BUFFER] __used __NOCACHE;
+static __aligned(32) uint8_t long_tx_buf[TX_LONG_BUFFER] __used __NOCACHE;
 #else
-ZTEST_BMEM uint8_t long_rx_buf[1024];
-ZTEST_BMEM uint8_t long_rx_buf2[1024];
-ZTEST_BMEM uint8_t long_tx_buf[1000];
+ZTEST_BMEM uint8_t long_rx_buf[RX_LONG_BUFFER];
+ZTEST_BMEM uint8_t long_rx_buf2[RX_LONG_BUFFER];
+ZTEST_BMEM uint8_t long_tx_buf[TX_LONG_BUFFER];
 #endif /* NOCACHE_MEM */
 ZTEST_BMEM volatile uint8_t evt_num;
 ZTEST_BMEM size_t long_received[2];
@@ -887,7 +890,7 @@ static void test_long_buffers_callback(const struct device *dev,
 		k_sem_give(&rx_disabled);
 		break;
 	case UART_RX_BUF_REQUEST:
-		uart_rx_buf_rsp(dev, next_buffer, 1024);
+		uart_rx_buf_rsp(dev, next_buffer, RX_LONG_BUFFER);
 		next_buffer = (next_buffer == long_rx_buf2) ? long_rx_buf : long_rx_buf2;
 		break;
 	default:
@@ -906,36 +909,41 @@ static void *long_buffers_setup(void)
 
 ZTEST_USER(uart_async_long_buf, test_long_buffers)
 {
+	size_t tx_len1 = TX_LONG_BUFFER / 2;
+	size_t tx_len2 = TX_LONG_BUFFER;
+
 	memset(long_rx_buf, 0, sizeof(long_rx_buf));
 	memset(long_tx_buf, 1, sizeof(long_tx_buf));
 
 	uart_rx_enable(uart_dev, long_rx_buf, sizeof(long_rx_buf), 10 * USEC_PER_MSEC);
 
-	uart_tx(uart_dev, long_tx_buf, 500, 200 * USEC_PER_MSEC);
+	uart_tx(uart_dev, long_tx_buf, tx_len1, 200 * USEC_PER_MSEC);
 	zassert_equal(k_sem_take(&tx_done, K_MSEC(200)), 0, "TX_DONE timeout");
 	zassert_equal(k_sem_take(&rx_rdy, K_MSEC(200)), 0, "RX_RDY timeout");
-	zassert_equal(long_received[0], 500, "Wrong number of bytes received.");
-	zassert_equal(memcmp(long_tx_buf, long_rx_buf, 500),
+	zassert_equal(long_received[0], tx_len1, "Wrong number of bytes received.");
+	zassert_equal(memcmp(long_tx_buf, long_rx_buf, tx_len1),
 		      0,
 		      "Buffers not equal");
 	k_msleep(10);
 	/* Check if instance is releasing a buffer after the timeout. */
 	bool release_on_timeout = k_sem_take(&rx_buf_released, K_NO_WAIT) == 0;
 
 	evt_num = 0;
-	uart_tx(uart_dev, long_tx_buf, 1000, 200 * USEC_PER_MSEC);
+	uart_tx(uart_dev, long_tx_buf, tx_len2, 200 * USEC_PER_MSEC);
 	zassert_equal(k_sem_take(&tx_done, K_MSEC(200)), 0, "TX_DONE timeout");
 	zassert_equal(k_sem_take(&rx_rdy, K_MSEC(200)), 0, "RX_RDY timeout");
 
 	if (release_on_timeout) {
-		zassert_equal(long_received[0], 1000, "Wrong number of bytes received.");
+		zassert_equal(long_received[0], tx_len2, "Wrong number of bytes received.");
 		zassert_equal(memcmp(long_tx_buf, long_rx_buf2, long_received[0]), 0,
 			      "Buffers not equal");
 	} else {
 		zassert_equal(k_sem_take(&rx_rdy, K_MSEC(200)), 0, "RX_RDY timeout");
-		zassert_equal(long_received[0], 524, "Wrong number of bytes received.");
-		zassert_equal(long_received[1], 476, "Wrong number of bytes received.");
-		zassert_equal(memcmp(long_tx_buf, long_rx_buf + 500, long_received[0]), 0,
+		zassert_equal(long_received[0], RX_LONG_BUFFER - tx_len1,
+				"Wrong number of bytes received.");
+		zassert_equal(long_received[1], tx_len2 - (RX_LONG_BUFFER - tx_len1),
+				"Wrong number of bytes received.");
+		zassert_equal(memcmp(long_tx_buf, long_rx_buf + tx_len1, long_received[0]), 0,
 			      "Buffers not equal");
 		zassert_equal(memcmp(long_tx_buf, long_rx_buf2, long_received[1]), 0,
 			      "Buffers not equal");