[PATCH v4 7/8] ARM: dts: Declare UART1 on zx297520v3 boards

Stefan Dösinger
2026-04-16T20:20:08Z

This is the UART that sends Uboot messages and is accessible via pins on
the boards I have seen so far. UART0 and UART2 exist as well in the SoC
and can be used with the right pinmux settings on some boards. They will
be added later.

Signed-off-by: Stefan Dösinger <stefandoesinger@gmail.com>

---

The reason why I add the serial1=uart1 alias is to keep console=ttyAMA1
stable regardless of the other enabled UARTs. UART0, as the name
implies, has a lower MMIO address, but uart1 is the one that usually has
the boot output and console.
---
arch/arm/boot/dts/zte/zx297520v3.dtsi | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/arch/arm/boot/dts/zte/zx297520v3.dtsi b/arch/arm/boot/dts/zte/zx297520v3.dtsi
index ecd07f3fb8b3..09fbb1d052e3 100644
--- a/arch/arm/boot/dts/zte/zx297520v3.dtsi
+++ b/arch/arm/boot/dts/zte/zx297520v3.dtsi
@@ -6,6 +6,10 @@ / {
#address-cells = <1>;
#size-cells = <1>;

+ aliases {
+ serial1 = &uart1;
+ };
+
cpus {
#address-cells = <1>;
#size-cells = <0>;
@@ -57,5 +61,23 @@ timer {
*/
arm,cpu-registers-not-fw-configured;
};
+
+ /* The UART clock defaults to 26 mhz. It will be replaced when the zx29 clock
+ * framework is added.
+ */
+ uartclk: uartclk: clock-26000000 {
+ #clock-cells = <0>;
+ compatible = "fixed-clock";
+ clock-frequency = <26000000>;
+ };
+
+ uart1: serial@1408000 {
+ compatible = "arm,pl011", "arm,primecell";
+ arm,primecell-periphid = <0x001feffe>;
+ reg = <0x01408000 0x1000>;
+ interrupts = <GIC_SPI 1 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&uartclk>;
+ clock-names = "apb_pclk";
+ };
};
};

--
2.52.0