fix(lp_uart): Fixed flaky LP UART unit tests

This commit fixes some flaky LP UART multi device tests. It also adds
code to put the HP core to light sleep for few tests.

Author: sudeep-mohanty

components/ulp/test_apps/lp_core/lp_core_basic_tests/main/lp_core/test_main_uart.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -10,6 +10,7 @@
 #include "ulp_lp_core_utils.h"
 #include "ulp_lp_core_uart.h"
 #include "ulp_lp_core_print.h"
+#include "soc/soc_caps.h"
 
 #define LP_UART_PORT_NUM            LP_UART_NUM_0
 #define LP_UART_BUFFER_LEN          UART_BUF_SIZE
@@ -95,5 +96,10 @@ int main(void)
         /* Synchronize with the HP core running the test */
         test_cmd = LP_CORE_NO_COMMAND;
         test_cmd_reply = LP_CORE_COMMAND_OK;
+
+        /* Wake up the HP core */
+#if SOC_LIGHT_SLEEP_SUPPORTED
+        ulp_lp_core_wakeup_main_processor();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
     }
 }

components/ulp/test_apps/lp_core/lp_core_basic_tests/main/test_lp_core_uart.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -18,6 +18,10 @@
 #include "esp_log.h"
 
 #include "driver/uart.h"
+#include "soc/soc_caps.h"
+#if SOC_LIGHT_SLEEP_SUPPORTED
+#include "esp_sleep.h"
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
 
 extern const uint8_t lp_core_main_uart_bin_start[] asm("_binary_lp_core_test_app_uart_bin_start");
 extern const uint8_t lp_core_main_uart_bin_end[]   asm("_binary_lp_core_test_app_uart_bin_end");
@@ -136,6 +140,9 @@ static void setup_test_print_data(void)
 
 static void hp_uart_read(void)
 {
+    /* Wait for LP UART to be initialized first */
+    unity_wait_for_signal("LP UART init done");
+
     /* Configure HP UART driver */
     uart_config_t hp_uart_cfg = {
         .baud_rate = lp_uart_cfg.uart_proto_cfg.baud_rate,
@@ -203,6 +210,9 @@ static void test_lp_uart_write(void)
     /* Setup LP UART with default configuration */
     TEST_ASSERT(ESP_OK == lp_core_uart_init(&lp_uart_cfg));
 
+    /* Notify HP UART once LP UART is initialized */
+    unity_send_signal("LP UART init done");
+
     /* Wait for the HP UART device to be initialized */
     unity_wait_for_signal("HP UART init done");
 
@@ -216,9 +226,22 @@ static void test_lp_uart_write(void)
     setup_test_data((uint8_t *)&ulp_tx_data, NULL);
     ulp_tx_len = TEST_DATA_LEN + sizeof(start_pattern);
 
+    /* Configure ULP wakeup source */
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    esp_sleep_enable_ulp_wakeup();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
     /* Start the test */
     ESP_LOGI(TAG, "Write test start");
     ulp_test_cmd = LP_CORE_LP_UART_WRITE_TEST;
+
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    /* Enter light sleep */
+    esp_light_sleep_start();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
+    vTaskDelay(10);
+    TEST_ASSERT_EQUAL(ulp_test_cmd_reply, LP_CORE_COMMAND_OK);
 }
 
 static void hp_uart_read_options(void)
@@ -310,13 +333,29 @@ static void test_lp_uart_write_options(void)
     setup_test_data((uint8_t *)&ulp_tx_data, NULL);
     ulp_tx_len = TEST_DATA_LEN + sizeof(start_pattern);
 
+    /* Configure ULP wakeup source */
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    esp_sleep_enable_ulp_wakeup();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
     /* Start the test */
     ESP_LOGI(TAG, "Write test start");
     ulp_test_cmd = LP_CORE_LP_UART_WRITE_TEST;
+
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    /* Enter light sleep */
+    esp_light_sleep_start();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
+    vTaskDelay(10);
+    TEST_ASSERT_EQUAL(ulp_test_cmd_reply, LP_CORE_COMMAND_OK);
 }
 
 static void hp_uart_write(void)
 {
+    /* Wait for LP UART to be initialized first */
+    unity_wait_for_signal("LP UART init done");
+
     /* Configure HP UART driver */
     uart_config_t hp_uart_cfg = {
         .baud_rate = lp_uart_cfg.uart_proto_cfg.baud_rate,
@@ -365,6 +404,9 @@ static void test_lp_uart_read(void)
     /* Setup LP UART with updated configuration */
     TEST_ASSERT(ESP_OK == lp_core_uart_init(&lp_uart_cfg));
 
+    /* Notify HP UART once LP UART is initialized */
+    unity_send_signal("LP UART init done");
+
     /* Wait for the HP UART device to be initialized */
     unity_wait_for_signal("HP UART init done");
 
@@ -409,6 +451,9 @@ static void test_lp_uart_read(void)
 
 static void hp_uart_write_options(void)
 {
+    /* Wait for LP UART to be initialized first */
+    unity_wait_for_signal("LP UART init done");
+
     /* Configure HP UART driver */
     uart_config_t hp_uart_cfg = {
         .baud_rate = lp_uart_cfg1.uart_proto_cfg.baud_rate,
@@ -457,6 +502,9 @@ static void test_lp_uart_read_options(void)
     /* Setup LP UART with updated configuration */
     TEST_ASSERT(ESP_OK == lp_core_uart_init(&lp_uart_cfg1));
 
+    /* Notify HP UART once LP UART is initialized */
+    unity_send_signal("LP UART init done");
+
     /* Wait for the HP UART device to be initialized */
     unity_wait_for_signal("HP UART init done");
 
@@ -504,6 +552,9 @@ static void test_lp_uart_read_multi_byte(void)
     /* Setup LP UART with updated configuration */
     TEST_ASSERT(ESP_OK == lp_core_uart_init(&lp_uart_cfg));
 
+    /* Notify HP UART once LP UART is initialized */
+    unity_send_signal("LP UART init done");
+
     /* Wait for the HP UART device to be initialized */
     unity_wait_for_signal("HP UART init done");
 
@@ -550,6 +601,9 @@ static void test_lp_uart_read_multi_byte(void)
 
 static void hp_uart_read_print(void)
 {
+    /* Wait for LP UART to be initialized first */
+    unity_wait_for_signal("LP UART init done");
+
     /* Configure HP UART driver */
     uart_config_t hp_uart_cfg = {
         .baud_rate = lp_uart_cfg.uart_proto_cfg.baud_rate,
@@ -629,6 +683,9 @@ static void test_lp_uart_print(void)
     /* Setup LP UART with default configuration */
     TEST_ASSERT(ESP_OK == lp_core_uart_init(&lp_uart_cfg));
 
+    /* Notify HP UART once LP UART is initialized */
+    unity_send_signal("LP UART init done");
+
     /* Wait for the HP UART device to be initialized */
     unity_wait_for_signal("HP UART init done");
 
@@ -647,9 +704,22 @@ static void test_lp_uart_print(void)
     ulp_test_hex = test_hex;
     ulp_test_character = test_character;
 
+    /* Configure ULP wakeup source */
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    esp_sleep_enable_ulp_wakeup();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
     /* Start the test */
     ESP_LOGI(TAG, "LP Core print test start");
     ulp_test_cmd = LP_CORE_LP_UART_PRINT_TEST;
+
+#if SOC_LIGHT_SLEEP_SUPPORTED
+    /* Enter light sleep */
+    esp_light_sleep_start();
+#endif /* SOC_LIGHT_SLEEP_SUPPORTED */
+
+    vTaskDelay(10);
+    TEST_ASSERT_EQUAL(ulp_test_cmd_reply, LP_CORE_COMMAND_OK);
 }
 
 /* Test LP UART write operation with default LP UART initialization configuration */