diff --git a/micropython/bootloader/main.c b/micropython/bootloader/main.c
index 7842caec1a..f6e4732bd7 100644
--- a/micropython/bootloader/main.c
+++ b/micropython/bootloader/main.c
@@ -20,24 +20,6 @@ void pendsv_isr_handler(void) {
     __fatal_error("pendsv");
 }
 
-void periph_init(void)
-{
-    HAL_Init();
-
-    SystemClock_Config();
-
-    __GPIOA_CLK_ENABLE();
-    __GPIOB_CLK_ENABLE();
-    __GPIOC_CLK_ENABLE();
-    __GPIOD_CLK_ENABLE();
-
-    sdcard_init();
-
-    display_init();
-    display_clear();
-    display_backlight(255);
-}
-
 bool check_sdcard(void)
 {
     BOOTLOADER_PRINTLN("checking for SD card");
@@ -136,6 +118,12 @@ int main(void)
 {
     periph_init();
 
+    sdcard_init();
+
+    display_init();
+    display_clear();
+    display_backlight(255);
+
     BOOTLOADER_PRINTLN("TREZOR Bootloader");
     BOOTLOADER_PRINTLN("=================");
     BOOTLOADER_PRINTLN("starting bootloader");
diff --git a/micropython/firmware/main.c b/micropython/firmware/main.c
index 69bd3204d2..ceee2f0430 100644
--- a/micropython/firmware/main.c
+++ b/micropython/firmware/main.c
@@ -23,33 +23,7 @@
 
 int main(void) {
 
-    // STM32F4xx HAL library initialization:
-    //  - configure the Flash prefetch, instruction and data caches
-    //  - configure the Systick to generate an interrupt each 1 msec
-    //  - set NVIC Group Priority to 4
-    //  - global MSP (MCU Support Package) initialization
-    HAL_Init();
-
-    // Set the system clock to be HSE
-    SystemClock_Config();
-
-    // Enable GPIO clocks
-    __HAL_RCC_GPIOA_CLK_ENABLE();
-    __HAL_RCC_GPIOB_CLK_ENABLE();
-    __HAL_RCC_GPIOC_CLK_ENABLE();
-    __HAL_RCC_GPIOD_CLK_ENABLE();
-
-    // Enable the CCM RAM
-    __HAL_RCC_CCMDATARAMEN_CLK_ENABLE();
-
-    // Clear the reset flags
-    PWR->CR |= PWR_CR_CSBF;
-    RCC->CSR |= RCC_CSR_RMVF;
-
-    // Enable CPU ticks
-    CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;  // Enable DWT
-    DWT->CYCCNT = 0;  // Reset Cycle Count Register
-    DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;  // Enable Cycle Count Register
+    periph_init();
 
     pendsv_init();
 
diff --git a/micropython/loader/main.c b/micropython/loader/main.c
index f515ffccf8..0141e20f3e 100644
--- a/micropython/loader/main.c
+++ b/micropython/loader/main.c
@@ -15,25 +15,13 @@ void pendsv_isr_handler(void) {
     __fatal_error("pendsv");
 }
 
-void periph_init(void)
+int main(void)
 {
-    HAL_Init();
-
-    SystemClock_Config();
-
-    __GPIOA_CLK_ENABLE();
-    __GPIOB_CLK_ENABLE();
-    __GPIOC_CLK_ENABLE();
-    __GPIOD_CLK_ENABLE();
+    periph_init();
 
     display_init();
     display_clear();
     display_backlight(255);
-}
-
-int main(void)
-{
-    periph_init();
 
     __fatal_error("end reached");
 
diff --git a/micropython/trezorhal/common.c b/micropython/trezorhal/common.c
index e25114e71d..ec9cbd9c19 100644
--- a/micropython/trezorhal/common.c
+++ b/micropython/trezorhal/common.c
@@ -23,3 +23,36 @@ void __attribute__((noreturn)) __fatal_error(const char *msg) {
 void __attribute__((noreturn)) nlr_jump_fail(void *val) {
     __fatal_error("uncaught exception");
 }
+
+extern void SystemClock_Config(void);
+
+void periph_init(void) {
+
+    // STM32F4xx HAL library initialization:
+    //  - configure the Flash prefetch, instruction and data caches
+    //  - configure the Systick to generate an interrupt each 1 msec
+    //  - set NVIC Group Priority to 4
+    //  - global MSP (MCU Support Package) initialization
+    HAL_Init();
+
+    // Set the system clock to be HSE
+    SystemClock_Config();
+
+    // Enable GPIO clocks
+    __HAL_RCC_GPIOA_CLK_ENABLE();
+    __HAL_RCC_GPIOB_CLK_ENABLE();
+    __HAL_RCC_GPIOC_CLK_ENABLE();
+    __HAL_RCC_GPIOD_CLK_ENABLE();
+
+    // Enable the CCM RAM
+    __HAL_RCC_CCMDATARAMEN_CLK_ENABLE();
+
+    // Clear the reset flags
+    PWR->CR |= PWR_CR_CSBF;
+    RCC->CSR |= RCC_CSR_RMVF;
+
+    // Enable CPU ticks
+    CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;  // Enable DWT
+    DWT->CYCCNT = 0;  // Reset Cycle Count Register
+    DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;  // Enable Cycle Count Register
+}
diff --git a/micropython/trezorhal/common.h b/micropython/trezorhal/common.h
index e742bbd244..8df23bb4fa 100644
--- a/micropython/trezorhal/common.h
+++ b/micropython/trezorhal/common.h
@@ -1,7 +1,7 @@
 #ifndef __TREZORHAL_COMMON_H__
 #define __TREZORHAL_COMMON_H__
 
-void SystemClock_Config(void); // defined in stm32_system.c
+void periph_init(void);
 
 void __attribute__((noreturn)) nlr_jump_fail(void *val);