一. 简介
本文是基于RK3588平台，MIPI屏调试总结。
二. MIPI屏幕调试
2.1 调试总览，调试步骤分析
- 步骤 ① 先将背光点亮
- 步骤 ② 根据屏幕的规格书配置dsi1_panel节点
- 步骤 ③ 打开对应的dsi节点，开机logo
- 步骤 ④ 编译烧写，调试屏幕
2.2 DTS配置
#include "rk3588-evb.dtsi" //引用了dsi1_panel 节点
2.2.1 步骤 ① 背光配置：
dsi1_backlight: dsi1-backlight {status = "okay";compatible = "pwm-backlight";pwms = <&pwm2 0 25000 0>;brightness-levels = <0 20 20 21 21 22 22 2323 24 24 25 25 26 26 2727 28 28 29 29 30 30 3131 32 32 33 33 34 34 3535 36 36 37 37 38 38 3940 41 42 43 44 45 46 4748 49 50 51 52 53 54 5556 57 58 59 60 61 62 6364 65 66 67 68 69 70 7172 73 74 75 76 77 78 7980 81 82 83 84 85 86 8788 89 90 91 92 93 94 9596 97 98 99 100 101 102 103104 105 106 107 108 109 110 111112 113 114 115 116 117 118 119120 121 122 123 124 125 126 127128 129 130 131 132 133 134 135136 137 138 139 140 141 142 143144 145 146 147 148 149 150 151152 153 154 155 156 157 158 159160 161 162 163 164 165 166 167168 169 170 171 172 173 174 175176 177 178 179 180 181 182 183184 185 186 187 188 189 190 191192 193 194 195 196 197 198 199200 201 202 203 204 205 206 207208 209 210 211 212 213 214 215216 217 218 219 220 221 222 223224 225 226 227 228 229 230 231232 233 234 235 236 237 238 239240 241 242 243 244 245 246 247248 249 250 251 252 253 254 255>;default-brightness-level = <200>;enable-gpios = <&gpio2 RK_PC2 GPIO_ACTIVE_HIGH>;pinctrl-names = "default";pinctrl-0 = <&dsi1_backlight_en>;};
2.2.2 步骤 ② 根据datasheet配置屏幕节点：
-
屏幕上电初始化时序的配置教程见 RK3588-MIPI屏幕调试笔记:RK3588-MIPI-DSI之LCD上电初始化时序
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屏幕的时序参数配置教程见 RK3588-MIPI屏幕调试笔记:RK3588-MIPI-DSI之屏参配置
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屏幕dts配置如下：
&dsi1_panel {power-supply = <&vcc_lcd_mipi1>; //使用gpio模拟regulatorreset-gpios = <&gpio2 RK_PC1 GPIO_ACTIVE_LOW>;backlight = <&dsi1_backlight>;pinctrl-names = "default";pinctrl-0 = <&dsi1_lcd_rst_gpio>;panel-init-sequence = [13 00 02 B0 0113 00 02 C0 2613 00 02 C1 1013 00 02 C2 0E13 00 02 C3 0013 00 02 C4 0013 00 02 C5 2313 00 02 C6 1113 00 02 C7 2213 00 02 C8 2013 00 02 C9 1E13 00 02 CA 1C13 00 02 CB 0C13 00 02 CC 0A13 00 02 CD 0813 00 02 CE 0613 00 02 CF 1813 00 02 D0 0213 00 02 D1 0013 00 02 D2 0013 00 02 D3 0013 00 02 D4 2613 00 02 D5 0F13 00 02 D6 0D13 00 02 D7 0013 00 02 D8 0013 00 02 D9 2313 00 02 DA 1113 00 02 DB 2113 00 02 DC 1F13 00 02 DD 1D13 00 02 DE 1B13 00 02 DF 0B13 00 02 E0 0913 00 02 E1 0713 00 02 E2 0513 00 02 E3 1713 00 02 E4 0113 00 02 E5 0013 00 02 E6 0013 00 02 E7 0013 00 02 B0 0313 00 02 BE 0413 00 02 B9 4013 00 02 CC 8813 00 02 C8 0C13 00 02 C9 0713 00 02 CD 0113 00 02 CA 4013 00 02 CE 1A13 00 02 CF 6013 00 02 D2 0813 00 02 D3 0813 00 02 DB 0113 00 02 D9 0613 00 02 D4 0013 00 02 D5 0113 00 02 D6 0413 00 02 D7 0313 00 02 C2 0013 00 02 C3 0E13 00 02 C4 0013 00 02 C5 0E13 00 02 DD 0013 00 02 DE 0E13 00 02 E6 0013 00 02 E7 0E13 00 02 C2 0013 00 02 C3 0E13 00 02 C4 0013 00 02 C5 0E13 00 02 DD 0013 00 02 DE 0E13 00 02 E6 0013 00 02 E7 0E13 00 02 B0 0613 00 02 C0 A513 00 02 D5 1C13 00 02 C0 0013 00 02 B0 0013 00 02 BD 3013 00 02 F9 5C13 00 02 C2 1413 00 02 C4 1413 00 02 BF 1513 00 02 C0 0C13 00 02 B0 0013 00 02 B1 7913 00 02 BA 8F05 C8 01 1105 32 01 29];panel-exit-sequence = [05 00 01 2805 00 01 10];disp_timings1: display-timings { native-mode = <&dsi1_timing0>;dsi1_timing0: timing0 {clock-frequency = <159400000>; //根据屏幕的时序参数表配置hactive = <1200>;vactive = <1920>;hfront-porch = <80>;hsync-len = <1>;hback-porch = <60>;vfront-porch = <35>;vsync-len = <1>;vback-porch = <25>;hsync-active = <0>;vsync-active = <0>;de-active = <0>;pixelclk-active = <1>;};}; };
2.2.3 步骤 ③ 打开对应的dsi节点，开机logo
```
//打开背光的pwm节点
&pwm2 {status = "okay";pinctrl-names = "active";pinctrl-0 = <&pwm2m2_pins>;
};//在dsi1上接了一个mipi屏，这个配置开启dsi1&dsi1 {status = "okay";
};&mipi_dcphy1 {status = "okay";
};//默认dsi配置vp2和vp3上面，这里配置为dsi使用vp3，可以根据屏的分辨率来确认使用vp2还是vp3，vp2支持4K，vp3只支持 2048x1536
&dsi1_in_vp2 {status = "disabled";
};&dsi1_in_vp3 {status = "okay";
};//配置dsi1显示开机logo
&route_dsi1 {status = "okay";connect = <&vp3_out_dsi1>;
};
```
2.3 调试命令
查看显示信息命令：
cat /sys/kernel/debug/dri/0/summary
2.4 问题总结
调试过程中遇到的问题：一开始很久没亮，测量了电源电压和波形都正常。后来换了一组板子和屏幕做对比。最后是因为屏幕的座子没焊接好，二是接MIPI屏幕的排线太长会影响数据传输。换了一根短的线之后屏幕亮起。
