1.打上附件的补丁，支持多timing解析；
2.在你使用的dts文件中，加入新的timing支持；
--- a/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux-for-rk1808-cascade.dts
++ b/arch/arm64/boot/dts/rockchip/rk3399-sapphire-excavator-linux-for-rk1808-cascade.dts
@ -331,6 +331,22 @
de-active = <0>;
pixelclk-active = <0>;
};

+ timing_720p: timing-720p {
+ clock-frequency = <76000000>;
+ hactive = <1280>;
+ vactive = <720>;
+ hback-porch = <100>;
+ hfront-porch = <200>;
+ vback-porch = <10>;
+ vfront-porch = <10>;
+ hsync-len = <20>;
+ vsync-len = <20>;
+ hsync-active = <0>;
+ vsync-active = <0>;
+ de-active = <0>;
+ pixelclk-active = <0>;
+ };
};
};
3. 通过modetest可以看到dsi里面有2组timing

93 0 connected DSI-1 0x0 2 92
modes:
name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot)
1920x1080 60 1920 2040 2060 2260 1080 1082 1092 1112 220000 flags: nhsync, nvsync; type: preferred, driver
1280x720 60 1280 2120 2140 2240 720 1090 1110 1120 76000 flags: nhsync, nvsync; type: preferred, driver

4. 通过串口配置新的分辨率：
setprop persist.sys.resolution.main 1280x720p60
setprop sys.display.timeline N

N的值每次加1