diff --git a/arch/arm/src/stm32f7/stm32_rcc.h b/arch/arm/src/stm32f7/stm32_rcc.h
index 9320c34aa6..cfa3a6cdcf 100644
--- a/arch/arm/src/stm32f7/stm32_rcc.h
+++ b/arch/arm/src/stm32f7/stm32_rcc.h
@@ -243,6 +243,26 @@ void stm32_rcc_enablelsi(void);
 
 void stm32_rcc_disablelsi(void);
 
+#if defined(CONFIG_STM32F7_STM32F76XX) || defined(CONFIG_STM32F7_STM32F77XX)
+/****************************************************************************
+ * Name: stm32f7x9_rcc_dsisrcphy
+ *
+ * Description:
+ *   Set DSI clock source to DSI PHY
+ *
+ ****************************************************************************/
+void stm32f7x9_rcc_dsisrcphy(void);
+
+/****************************************************************************
+ * Name: stm32f7x9_rcc_dsisrcpllr
+ *
+ * Description:
+ *   Set DSI clock source to PLLR
+ *
+ ****************************************************************************/
+void stm32f7x9_rcc_dsisrcpllr(void);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }
diff --git a/arch/arm/src/stm32f7/stm32f76xx77xx_rcc.c b/arch/arm/src/stm32f7/stm32f76xx77xx_rcc.c
index 66cdb10031..e86e6a80d7 100644
--- a/arch/arm/src/stm32f7/stm32f76xx77xx_rcc.c
+++ b/arch/arm/src/stm32f7/stm32f76xx77xx_rcc.c
@@ -985,3 +985,22 @@ static inline void rcc_enableperipherals(void)
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
+void stm32f7x9_rcc_dsisrcphy(void)
+{
+  uint32_t regval;
+  regval  = getreg32(STM32_RCC_DCKCFGR2);
+  regval &= ~(RCC_DCKCFGR2_DSISEL_MASK);
+
+  regval |= (RCC_DCKCFGR2_DSISEL_PHY);
+  putreg32(regval, STM32_RCC_DCKCFGR2);
+}
+
+void stm32f7x9_rcc_dsisrcpllr(void)
+{
+  uint32_t regval;
+  regval  = getreg32(STM32_RCC_DCKCFGR2);
+  regval &= ~RCC_DCKCFGR2_DSISEL_MASK;
+
+  regval |= RCC_DCKCFGR2_DSISEL_SYSCLK;
+  putreg32(regval, STM32_RCC_DCKCFGR2);
+}