diff --git a/cpu/esp32/startup.c b/cpu/esp32/startup.c
index e3d8ff2dc8..6311758f2a 100644
--- a/cpu/esp32/startup.c
+++ b/cpu/esp32/startup.c
@@ -150,6 +150,10 @@ static NORETURN void IRAM system_startup_cpu0(void)
     /* initialize system call tables of ESP32x rom and newlib */
     syscalls_init();
 
+    /* systemwide UART initialization */
+    extern void uart_system_init (void);
+    uart_system_init();
+
     /* initialize stdio */
     esp_rom_uart_tx_wait_idle(CONFIG_ESP_CONSOLE_UART_NUM);
     early_init();
@@ -234,10 +238,6 @@ static NORETURN void IRAM system_init (void)
     /* install exception handlers */
     init_exceptions();
 
-    /* systemwide UART initialization */
-    extern void uart_system_init (void);
-    uart_system_init();
-
     /* set log levels for SDK library outputs */
     extern void esp_log_level_set(const char* tag, esp_log_level_t level);
     esp_log_level_set("wifi", LOG_DEBUG);
diff --git a/cpu/esp_common/periph/uart.c b/cpu/esp_common/periph/uart.c
index 021bf2a3d0..91771d3752 100644
--- a/cpu/esp_common/periph/uart.c
+++ b/cpu/esp_common/periph/uart.c
@@ -60,6 +60,7 @@
 #else /* defined(MCU_ESP8266) */
 
 #include "esp_rom_gpio.h"
+#include "esp_rom_uart.h"
 #include "hal/interrupt_controller_types.h"
 #include "hal/interrupt_controller_ll.h"
 #include "soc/gpio_reg.h"
@@ -68,6 +69,7 @@
 #include "soc/periph_defs.h"
 #include "soc/rtc.h"
 #include "soc/soc_caps.h"
+#include "soc/uart_pins.h"
 #include "soc/uart_reg.h"
 #include "soc/uart_struct.h"
 
@@ -166,7 +168,10 @@ int uart_init(uart_t uart, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
     assert(uart < UART_NUMOF);
 
 #ifndef MCU_ESP8266
-    /* reset the pins when they were already used as UART pins */
+    assert(uart_config[uart].txd != GPIO_UNDEF);
+    assert(uart_config[uart].rxd != GPIO_UNDEF);
+
+    /* reset the pin usage when they were already used as UART pins */
     if (gpio_get_pin_usage(uart_config[uart].txd) == _UART) {
         gpio_set_pin_usage(uart_config[uart].txd, _GPIO);
     }
@@ -186,6 +191,7 @@ int uart_init(uart_t uart, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
     gpio_set_pin_usage(uart_config[uart].txd, _UART);
     gpio_set_pin_usage(uart_config[uart].rxd, _UART);
 
+    esp_rom_uart_tx_wait_idle(uart);
     esp_rom_gpio_connect_out_signal(uart_config[uart].txd,
                                     _uarts[uart].signal_txd, false, false);
     esp_rom_gpio_connect_in_signal(uart_config[uart].rxd,
@@ -247,6 +253,18 @@ void uart_system_init(void)
         /* reset all UART interrupt status registers */
         _uarts[uart].regs->int_clr.val = ~0;
     }
+#ifndef MCU_ESP8266
+    /* reset the pin usage of the default UART0 pins to GPIO to allow
+     * reinitialization and usage for other purposes */
+    gpio_set_pin_usage(U0TXD_GPIO_NUM, _GPIO);
+    gpio_set_pin_usage(U0RXD_GPIO_NUM, _GPIO);
+#if defined(CONFIG_CONSOLE_UART_TX) && defined(CONFIG_CONSOLE_UART_TX)
+    /* reset the pin usage of the UART pins used by the bootloader to
+     * _GPIO to be able to use them later for other purposes */
+    gpio_set_pin_usage(CONFIG_CONSOLE_UART_TX, _GPIO);
+    gpio_set_pin_usage(CONFIG_CONSOLE_UART_RX, _GPIO);
+#endif
+#endif
 }
 
 void uart_print_config(void)