diff --git a/arch/arm/boot/dts/microchip/sama7d65.dtsi b/arch/arm/boot/dts/microchip/sama7d65.dtsi
index 4db7c2f7518b..ad1464c7b8c6 100644
--- a/arch/arm/boot/dts/microchip/sama7d65.dtsi
+++ b/arch/arm/boot/dts/microchip/sama7d65.dtsi
@@ -414,6 +414,7 @@ uart0: serial@200 {
 				dma-names = "tx", "rx";
 				atmel,use-dma-rx;
 				atmel,use-dma-tx;
+				atmel,fifo-size = <32>;
 				atmel,usart-mode = <AT91_USART_MODE_SERIAL>;
 				status = "disabled";
 			};
@@ -492,6 +493,7 @@ uart2: serial@200 {
 				dma-names = "tx", "rx";
 				atmel,use-dma-rx;
 				atmel,use-dma-tx;
+				atmel,fifo-size = <32>;
 				atmel,usart-mode = <AT91_USART_MODE_SERIAL>;
 				status = "disabled";
 			};
@@ -517,6 +519,7 @@ uart3: serial@200 {
 				dma-names = "tx", "rx";
 				atmel,use-dma-rx;
 				atmel,use-dma-tx;
+				atmel,fifo-size = <32>;
 				atmel,usart-mode = <AT91_USART_MODE_SERIAL>;
 				status = "disabled";
 			};