AM5728: Linux/AM5728: uart configuration problem

Part Number: AM5728

I have a AM5728 custom board.

I use  ti-processor-sdk-linux-rt-am57xx-evm-06.03.00.106-Linux-x86-Install.bin

I enable uart1 and uart4~9 in am57xx-beagle-x15-common.dtsi,

but only uart1, uart8 and uart9 can be used, other uart cannot be used.

What is the problem and how can I solve it?

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&uart1 {
status = "okay";

};

&uart3 {
status = "okay";
interrupts-extended = <&crossbar_mpu GIC_SPI 69 IRQ_TYPE_LEVEL_HIGH>,
<&dra7_pmx_core 0x3f8>;
};

&uart4 {
status = "okay";
};

&uart5 {
status = "okay";
};

&uart6 {
status = "okay";
};

&uart7 {
status = "okay";
};
&uart8 {
status = "okay";
};
&uart9 {
status = "okay";
};