--- tags: Android BSP Development --- # Qucomm MIPI DSI LCD Bring Up ## MIPI DSI介紹 **MIPI**是**Mobile Industry Processor Interface**的縮寫。MIPI是MIPI聯盟發起的為手機處理器制定的開放標準。 已經完成和正在計畫的規範如下： ![](https://i.imgur.com/nXvwjja.png) ##### 名詞解釋 - DCS (DisplayCommandSet)：DCS是一個標準化的命令集，用於命令模式的顯示模組 - DSI (DisplaySerialInterface) : DSI 定義一個介於處理器和顯示模组間的高速串行接口 - CSI (CameraSerialInterface) : CSI 定義一個介於處理器和攝像模组間的高速串行接口 - D-PHY：提供DSI和CSI的物理層定義 ##### DSI分層結構 DSI分四層 - PHY層定義了傳輸媒介，輸入/輸出電路和和時鐘和信號機制。 - Lane Management層：發送和收集數據流到每條lane。 - Low Level Protocol層：定義了如何组帧和解析以及錯誤檢測等。 - Application層：描述高層編碼和解析數據流。 ![](https://i.imgur.com/l2hn74G.png) ##### Command和Video模式 - DSI兼容的外設支持Command或Video操作模式，用哪個模式由外設的架構决定 - Command模式是指採用發送命令和數據到具有顯示缓存的控制器。主机通過命令間接的控制外設。Command模式採用雙向接口 - Video模式是指從主机傳輸到外設採用时实象素流。這種模式只能以**高速傳輸**。為减少複雜性和節約成本，只採用Video模式的系统可能只有一個單項數據路徑 ## 使用Qcomm工具Bring up LCD ### Display Driver Development Procedure 1. Install the library by the command below. ``` $ sudo apt-get install libxml-libxml-perl libxml-perl ``` 2. Enter the tools directory *$ cd device/qcom/common/display/tools* which will show information as below: ``` device/qcom/common/display/tools$ ls panel_hx8394f_720p_video.xml panel_ili9881c_720p_video.xml panel_nt35590_720p_cmd.xml panel_nt35596_1080p_video.xml parser.pl platform-msm8610.xml README.txt ``` 3. Copy the panel_nt35596_1080p_video.xml to a new <oem_panel_input_file>.xml, if the LCD is in video mode. In my case, LCD use vedio mode. ``` $ cp panel_nt35596_1080p_video.xml panel_mydemo_1080p_video.xml ``` ### Edit the new XML to configure the display parameters. (According my LCD spec) #### Panel Information ``` 32 <GCDB> 33 <Version>"1.0"</Version> 34 <PanelId>mydemo-1080p-video</PanelId> 35 <PanelH>mydemo_1080p_video</PanelH> 36 <PanelEntry> ``` | XML Tag | Description | | ------- | ----------------------------------------------- | | Version | Each version is bind to be a set of panel tags. | | PanelId | Name used to generate the .dtsi file for kernel | | PanelH | Name used to generate the header file for LK | #### Panel configuration ``` 38 <!-- Panel configuration --> 39 <PanelName>"my demo 1080p video mode dsi panel"</PanelName> 40 <PanelController>"mdss_dsi0"</PanelController> 41 <PanelInterface>10</PanelInterface> 42 <PanelType>0</PanelType> 43 <PanelDestination>"DISPLAY_1"</PanelDestination> 44 <PanelOrientation>0</PanelOrientation> 45 <PanelFrameRate>60</PanelFrameRate> 46 <PanelChannelId>0</PanelChannelId> 47 <DSIVirtualChannelId>0</DSIVirtualChannelId> 48 <PanelBroadcastMode>0</PanelBroadcastMode> 49 <!-- Optional Panel configuration --> 50 <!--BitClockFrequency>0</BitClockFrequency --> 51 <DSIStream>0</DSIStream> 52 <PanelCompatible>"qcom,mdss-dsi-panel"</PanelCompatible> 53 <InterleaveMode>0</InterleaveMode> ``` | XML Tag | Description | Value | | --------------------------------------- | ------------------------------------------------------- | ------------------------------------ | | PanelName | PanelName | Name/label value | | PanelType | Panel is in video mode or command mode | 0 = VIDEO_MODE<br />1 = COMMAND_MODE | | PanelOrientation<br />(Only used in LK) | Panel rotation value. | 1 = 0 degree<br />2 = 180 degree | | PanelFrameRate | An integer to define the panel refresh rate per second. | For example: 60 for 60fps panel. | #### Panel Resolution ``` 55 <!-- Panel Resolution --> 56 <PanelWidth>1200</PanelWidth> 57 <PanelHeight>1920</PanelHeight> 58 <HFrontPorch>60</HFrontPorch> 59 <HBackPorch>32</HBackPorch> 60 <HPulseWidth>1</HPulseWidth> 61 <HSyncSkew>0</HSyncSkew> 62 <VBackPorch>25</VBackPorch> 63 <VFrontPorch>35</VFrontPorch> 64 <VPulseWidth>1</VPulseWidth> 65 <HLeftBorder>0</HLeftBorder> 66 <HRightBorder>0</HRightBorder> 67 <VTopBorder>0</VTopBorder> 68 <VBottomBorder>0</VBottomBorder> 69 <!-- Optional Panel resolution configuration --> 70 <!--HActiveRes>0</HActiveRes> 71 <VActiveRes>100</VActiveRes> 72 <InvertDataPolarity>0</InvertDataPolarity> 73 <InvertVsyncPolarity>0</InvertVsyncPolarity> 74 <InvertHsyncPolarity>0</InvertHsyncPolarity --> ``` ![](https://i.imgur.com/yppziHp.png) ##### Panel Color Information ``` 76 <!-- Panel Color Information --> 77 <ColorFormat>24</ColorFormat> 78 <ColorOrder>0</ColorOrder> 79 <UnderFlowColor>0xff</UnderFlowColor> 80 <BorderColor>0</BorderColor> ``` | XML Tag | Description | Value | | ----------- | ---------------------------------------------------------- | ------------------------------------------------------------ | | ColorFormat | Defines the bits per pixel. | 24 = 888_RGB<br />18 = 666_RGB<br />16 = 565_RGB<br />12 = 444_RGB<br />8 = 332_RGB<br />3 = 111_RGB | | ColorOrder | Defines pixel component color order between MSM and panel. | 0 = DSI_RGB_SWAP_RGB<br />1 = DSI_RGB_SWAP_RBG<br />2 = DSI_RGB_SWAP_BGR<br />3 = DSI_RGB_SWAP_BRG<br />4 = DSI_RGB_SWAP_GRB<br />5 = DSI_RGB_SWAP_GBR | #### Video mode panel information ``` 608 <!-- Video mode panel information --> 609 <HSyncPulse>1</HSyncPulse> 610 <HFPPowerMode>0</HFPPowerMode> 611 <HBPPowerMode>0</HBPPowerMode> 612 <HSAPowerMode>0</HSAPowerMode> 613 <BLLPEOFPowerMode>1</BLLPEOFPowerMode> 614 <BLLPPowerMode>1</BLLPPowerMode> 615 <TrafficMode>2</TrafficMode> 616 <DMADelayAfterVsync>0</DMADelayAfterVsync> 617 <BLLPEOFPower>0x9</BLLPEOFPower> ``` | XML Tag | Description | Value | | ----------- | ------------------------------------------------------------ | ------------------------------------------------------------ | | HSyncPulse | Horizontal sync pulses. <br />It determines whether the hardware <br />should send horizontal sync pulses<br />during the vertical blanking period. | 0 = Sync pulse disable<br />1 = Sync pulse enable | | TrafficMode | Panel traffic mode type | 0 = non burst with sync pulses<br />1 = non burst with sync start event<br />2 = burst mode | Usually these parameters do not need to be modified. The user may need to note the parameter <TrafficMode> which may vary with the LCD chip. #### Lane Configuration ``` 619 <!-- Lane Configuration --> 620 <DSILanes>4</DSILanes> 621 <DSILaneMap>0</DSILaneMap> 622 <Lane0State>1</Lane0State> 623 <Lane1State>1</Lane1State> 624 <Lane2State>1</Lane2State> 625 <Lane3State>1</Lane3State> ``` ![](https://i.imgur.com/3qT6sHk.png) #### Backlight Configuration ``` 634 <!-- Backlight --> 635 <BLInterfaceType>1</BLInterfaceType> 636 <BLMinLevel>100</BLMinLevel> 637 <BLMaxLevel>4095</BLMaxLevel> 638 <BLStep>100</BLStep> 639 <BLPMICModel>"PMIC_8941"</BLPMICModel> 640 <BLPMICControlType>0</BLPMICControlType> ``` | XML Tag | Description | Value | | ----------------- | -------------------------------------- | ------------------------------------------------------------ | | BLMinLevel | Minimum value of backlight. | | | BLMaxLevel | Maximum value of backlight. | | | BLPMICControlType | PMIC controller for current backlight. | 0 = PWM GPIO<br />1 = WLED<br />2 = DCS COMMANDS<br />3 = LPG | #### Panel Timing | XML Tag | Description | | ------------ | ------------------------------------------------------------ | | PanelTimings | An array of length 12 that specifies the physical timing settings for the panel | | TClkPost | DSI timing control clock post value | | TClkPre | DSI timing control clock pre value | Generate PanelTimings Value ![](https://i.imgur.com/6acqNkH.png) ![](https://i.imgur.com/2HbE9R1.png) ``` 627 <!-- Panel Timing --> 628 <PanelTimings>"0xf7, 0x3a, 0x28, 0x00, 0x6e, 0x72, 0x2c, 0x3e, 0x31, 0x03, 0x04, 0x00"</PanelTimings> 629 <DSIMDPTrigger>0</DSIMDPTrigger> 630 <DSIDMATrigger>4</DSIDMATrigger> 631 <TClkPost>0x2</TClkPost> 632 <TClkPre>0x2d</TClkPre> ``` #### Panel Command information ``` 82 <!-- Panel Command information --> 83 <OnCommand>"0x05, 0x01, 0x00, 0x00, 0x96, 0x00, 0x02, 0x28, 0x00, 84 0x05, 0x01, 0x00, 0x00, 0x32, 0x00, 0x02, 0x10, 0x00, 85 0x05, 0x01, 0x00, 0x00, 0x96, 0x00, 0x02, 0x11, 0x00, 86 0x05, 0x01, 0x00, 0x00, 0x32, 0x00, 0x02, 0x29, 0x00"</OnCommand> 87 <OffCommand>"0x05, 0x01, 0x00, 0x00, 0x32, 0x00, 0x02, 0x28, 0x00, 88 0x05, 0x01, 0x00, 0x00, 0x78, 0x00, 0x02, 0x10, 0x00"</OffCommand> 89 <OnCommandState>0</OnCommandState> 90 <OffCommandState>1</OffCommandState> ``` | XML Tag | Description | Value | | --------------- | ------------------------------------------------------------ | ------------------------------------ | | OnCommand | Array of variable length that lists the initialization commands of the panel | | | OffCommand | Array of variable length that lists the deinitialization commands of the panel | | | OnCommandState | Panel state when sending the on command. | 0 = DSI_LP_MODE<br />1 = DSI_HP_MODE | | OffCommandState | Panel state when sending the off command. | | Generally speaking, <OnCommandState> and <OffCommandState> only need to keep the default value. #### Panel Reset Sequence ``` 126 <!-- Panel Reset Sequence --> 127 <ResetSequence> 128 <PinState1>1</PinState1> 129 <PulseWidth1>20</PulseWidth1> 130 <PinState2>0</PinState2> 131 <PulseWidth2>1</PulseWidth2> 132 <PinState3>1</PinState3> 133 <PulseWidth3>20</PulseWidth3> 134 <EnableBit>2</EnableBit> 135 </ResetSequence> ``` ## Configure Kernel and LK ``` $ perl parser.pl panel_mydemo_1080p_video.xml panel $ ls dsi-panel-mydemo-1080p-video.dtsi panel_ili9881c_720p_video.xml panel_mydemo_1080p_video.xml panel_nt35596_1080p_video.xml platform-msm8610.xml panel_hx8394f_720p_video.xml panel_mydemo_1080p_video.h panel_nt35590_720p_cmd.xml parser.pl README.txt ``` #### Configure Kernel copy *dsi-panel-mydemo-1080p-video.dtsi* to the following directory: kernel/msm-3.18/arch/arm/boot/dts/qcom/. 1. Include .dtsi files. Path: kernel/msm-3.18/arch/arm/boot/dts/qcom/msm8953-mdss-panels.dtsi ![](https://i.imgur.com/Z1YCGsy.png) 2. Modify .dtsi files. Add DSI PHY 2.0.0 timing config to the following directory: kernel/msm-3.18/arch/arm/boot/dts/qcom/msm8953-mdss-panels.dtsi. ![](https://i.imgur.com/iJclfP5.png) The parameters of timing “*mdss-dsi-panel-timings-phy-v2*” are the same as that of the timimg configured in LK (bootable/bootloader/lk/dev/gcdb/display/include/panel_mydemo_1080p_video.h) “mydemo_1080p_phy2_video_timings”. ![](https://i.imgur.com/Zks2wvH.png) ``` &dsi_mydemo_1080p_video { qcom,mdss-dsi-panel-timings-phy-v2 = [ 24 20 08 09 05 03 04 a0 /*Data 0*/ 24 20 08 09 05 03 04 a0 /*Data 1*/ 24 20 08 0a 05 03 04 a0 /*Data 2*/ 24 20 08 09 05 03 04 a0 /*Data 3*/ 24 1d 08 09 05 03 04 a0]; /*CLK lane*/ }; ``` > For example, ![](https://i.imgur.com/rwEU53g.png) The following part should be modified also: Path: *kernel/msm-3.18/arch/arm/boot/dts/qcom/msm8953-mtp.dtsi* ![](https://i.imgur.com/lfaJUTu.png) 3. Configure the Backlight. Path: kernel/msm-3.18/arch/arm/boot/dts/qcom/msm8953-mtp.dtsi ![](https://i.imgur.com/VBzDTcu.png) The GPIO to control pwm is, qcom,mdss-dsi-pwm-gpio = <&pm8953_mpps 4 0>; ![](https://i.imgur.com/GnlkRQM.png) Configure backlight type qcom,mdss-dsi-bl-pmic-control-type: a string that specifies the implementation of backlight control for this panel. "bl_ctrl_pwm" = Backlight controlled by PWM GPIO "bl_ctrl_wled" = Backlight controlled by WLED "bl_ctrl_dcs" = Backlight controlled by DCS commands(for OLED panel backlight controller) Others: Unknown backlight control. (default) #### Configure LK After the file panel_mydemo_1080p_video.h is generated, please copy it to the directory bootable/bootloader/lk/dev/gcdb/display/include/. Customers need to configure the LK to add a new panel. 1. Add several parameters to panel_mydemo_1080p_video.h to avoid compiling error. ![](https://i.imgur.com/MqY6gRA.png) ![](https://i.imgur.com/WB0FWTX.png) 2. Add the DSI PHY 2.0.0 timing config ![](https://i.imgur.com/KyjcKyR.png) 3. Add a new panel. Path: bootable/bootloader/lk/target/msm8953/oem_panel.c ![](https://i.imgur.com/fWyKDJP.png) ![](https://i.imgur.com/k8vpcJh.png) ![](https://i.imgur.com/GVywfuc.png) 4. Add new panel selection branch in function “init_panel_data”. ![](https://i.imgur.com/poPO2y6.png) 5. Choose to use the new panel in function “oem_panel_select”. The “panel_id” will be passed to kernel. ![](https://i.imgur.com/ovKM7CE.png)