diff --git a/plat/st/common/include/stm32mp_common.h b/plat/st/common/include/stm32mp_common.h
index d260644..fbd0dda 100644
--- a/plat/st/common/include/stm32mp_common.h
+++ b/plat/st/common/include/stm32mp_common.h
@@ -48,7 +48,7 @@
 uint32_t stm32_iwdg_shadow_update(uint32_t iwdg_inst, uint32_t flags);
 #endif
 
-#if STM32MP_UART_PROGRAMMER
+#if STM32MP_UART_PROGRAMMER || !defined(IMAGE_BL2)
 /* Get the UART address from its instance number */
 uintptr_t get_uart_address(uint32_t instance_nb);
 #endif
diff --git a/plat/st/common/stm32mp_common.c b/plat/st/common/stm32mp_common.c
index 9cbba04..072155f 100644
--- a/plat/st/common/stm32mp_common.c
+++ b/plat/st/common/stm32mp_common.c
@@ -161,6 +161,8 @@
 	unsigned int console_flags;
 	uint32_t clk_rate;
 	int result;
+	uint32_t boot_itf __unused;
+	uint32_t boot_instance __unused;
 
 	result = dt_get_stdout_uart_info(&dt_uart_info);
 
@@ -171,6 +173,15 @@
 		return -ENODEV;
 	}
 
+#if STM32MP_UART_PROGRAMMER || !defined(IMAGE_BL2)
+	stm32_get_boot_interface(&boot_itf, &boot_instance);
+
+	if ((boot_itf == BOOT_API_CTX_BOOT_INTERFACE_SEL_SERIAL_UART) &&
+	    (get_uart_address(boot_instance) == dt_uart_info.base)) {
+		return -EACCES;
+	}
+#endif
+
 #if defined(IMAGE_BL2)
 	if (dt_set_stdout_pinctrl() != 0) {
 		return -ENODEV;
diff --git a/plat/st/stm32mp1/bl2_plat_setup.c b/plat/st/stm32mp1/bl2_plat_setup.c
index b55bc70..d52ac93 100644
--- a/plat/st/stm32mp1/bl2_plat_setup.c
+++ b/plat/st/stm32mp1/bl2_plat_setup.c
@@ -18,6 +18,7 @@
 #include <drivers/mmc.h>
 #include <drivers/st/bsec.h>
 #include <drivers/st/stm32_iwdg.h>
+#include <drivers/st/stm32_uart.h>
 #include <drivers/st/stm32mp_pmic.h>
 #include <drivers/st/stm32mp1_clk.h>
 #include <drivers/st/stm32mp1_pwr.h>
@@ -229,6 +230,16 @@
 
 	generic_delay_timer_init();
 
+#if STM32MP_UART_PROGRAMMER
+	/* Disable programmer UART before changing clock tree */
+	if (boot_context->boot_interface_selected ==
+	    BOOT_API_CTX_BOOT_INTERFACE_SEL_SERIAL_UART) {
+		uintptr_t uart_prog_addr =
+			get_uart_address(boot_context->boot_interface_instance);
+
+		stm32_uart_stop(uart_prog_addr);
+	}
+#endif
 	if (stm32mp1_clk_probe() < 0) {
 		panic();
 	}
diff --git a/plat/st/stm32mp1/stm32mp1_private.c b/plat/st/stm32mp1/stm32mp1_private.c
index eb8bc27..a8ffecb 100644
--- a/plat/st/stm32mp1/stm32mp1_private.c
+++ b/plat/st/stm32mp1/stm32mp1_private.c
@@ -167,7 +167,7 @@
 	}
 }
 
-#if STM32MP_UART_PROGRAMMER
+#if STM32MP_UART_PROGRAMMER || !defined(IMAGE_BL2)
 /*
  * UART Management
  */