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Co-authored-by: ZHANG Yuntian <[email protected]>

arch/arm64/boot/dts/rockchip/overlays/rockchip-uart-dma.dts

@@ -3,10 +3,12 @@
 
 / {
 	metadata {
-		title = "Switch all UART TX to DMA mode";
+		title = "Enable DMA transfer mode for all UARTs";
 		compatible = "rockchip,rk3566", "rockchip,rk3568", "rockchip,rk3588";
 		category = "misc";
-		description = "Switch all UART TX to DMA mode";
+		description = "Enable DMA transfer mode for all UARTs.
+DMA mode can help alleviating the CPU load when the data rate is high.
+It is not necessary to enable it at low data rate, as DMA requires additional resources to set up.";
 	};
 };