44.Linux君正X1000-添加st7789v显示

由于板子LCD旧屏是ili9335型号的,旧屏有时候会断货,如果断货则使用一个st7789v型号的LCD

它们两个屏的区别在于初始化屏的参数不同,引脚都一样,也就是说需要使板子同时支持ili9335型号和st7789v型号

思路:

1.uboot在显示LOG初始化屏参数)之前,通过命令来读LCD型号,来检测LCD型号,然后来修改初始化屏的参数.
2.如果屏是新屏,则设置bootargs,向内核传递参数lcd_type=new
3.当kernel收到参数lcd_type=new时,则在初始化LCD之前,修改屏的参数.

改uboot

首先来看单板配置信息,根据配置找到哪个文件是初始化LCD屏的

根据make ap60pro_uImage_sfc_nand命令,找ap60pro_uImage_sfc_nand单板信息

vi   ./u-boot/boards.cfg　　　　

找到:

# Target      ARCH   CPU   Board name  Vendor     SoC    Options
##############################################################
ap60pro_uImage_sfc_nand      mips        xburst      ap60pro       ingenic    x1000   ap60pro:SPL_SFC_NAND,LIBSLEEP,GET_BT_MAC

从上面看到board name为ap60pro,所以最终通过下面几个来初始化: 

./arch/mips/cpu/xburstx1000start.S    //启动代码
./include/configs/ap60pro.h             //各种define配置
./board/ingenic/ap60pro                 //单板配置源文件

查看ap60pro.h,查看LCD相关的define配置

查找CONFIG_ILI9335_240X320,找到在./board/ingenic/ap60pro/Makefile里调用:

COBJS-$CONFIG_ILI9335_240X320) += lcd-ili9335_240x320.o　　　　//保存LCD初始化参数的信息

查找CONFIG_ILI9335_240X320,找到在./drivers/video/Makefile里调用:

COBJS-$CONFIG_JZ_LCD_V13) +=  jz_lcd/jz_lcd_v13.o    　　　　//根据lcd-ili9335_240*320.c来初始化LCD

 

修改lcd-ili9335_240x320.c

添加st7789v初始化的数组表在代码中以New_ili9335_data_table数组表示):

struct smart_lcd_data_table ili9335_data_table[] = {    //旧屏的初始化参数表
{SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0xec},
    {SMART_CONFIG_DATA,0x1e},
    {SMART_CONFIG_DATA,0x8f},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x01},
    {SMART_CONFIG_DATA,0x01},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x02},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x03},
    {SMART_CONFIG_DATA,0x10},
    {SMART_CONFIG_DATA,0x30},

    {SMART_CONFIG_UDELAY,10000},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x08},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x02},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x09},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x0a},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x08}, //enable te
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x0d},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x0f},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x60},
    {SMART_CONFIG_DATA,0x27},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x61},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x6a},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_UDELAY,10000},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x10},
    {SMART_CONFIG_DATA,0x16},
    {SMART_CONFIG_DATA,0x90},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x11},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x27},
    
    {SMART_CONFIG_UDELAY,10000},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x12},
        {SMART_CONFIG_DATA,0x00},
        {SMART_CONFIG_DATA,0x0d},
    
    {SMART_CONFIG_UDELAY,10000},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x21},
    {SMART_CONFIG_DATA,0x16},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x29},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x18},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x2b},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x0a},
    
    {SMART_CONFIG_UDELAY,10000},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x20},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x21},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    //============Gamma============
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x30},
    {SMART_CONFIG_DATA,0x04},
    {SMART_CONFIG_DATA,0x03},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x31},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x07},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x32},
    {SMART_CONFIG_DATA,0x04},
    {SMART_CONFIG_DATA,0x04},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x35},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x02},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x36},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x0f},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x37},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x03},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x38},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x39},
    {SMART_CONFIG_DATA,0x03},
    {SMART_CONFIG_DATA,0x02},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x3c},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x3d},
    {SMART_CONFIG_DATA,0x0f},
    {SMART_CONFIG_DATA,0x00},
      //=============================
    // set RAM address
  {SMART_CONFIG_CMD,0x00},
   {SMART_CONFIG_CMD,0x50},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x51},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0xef},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x52},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x53},
    {SMART_CONFIG_DATA,0x01},
    {SMART_CONFIG_DATA,0x3f},
    
    {SMART_CONFIG_UDELAY,10000},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x80},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x81},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x82},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x83},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x84},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x85},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x90},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x10},

    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x91},
    {SMART_CONFIG_DATA,0x06},
    {SMART_CONFIG_DATA,0x00},

    //display on
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x07},
    {SMART_CONFIG_DATA,0x01},
    {SMART_CONFIG_DATA,0x33},
    
    {SMART_CONFIG_CMD,0x00},
    {SMART_CONFIG_CMD,0x22},
    
};


unsigned long truly_cmd_buf[]= {
    0x22002200,
};
struct jzfb_config_info jzfb1_init_data = {
    .num_modes = 1,
    .modes = &jzfb1_videomode,
    .lcd_type = LCD_TYPE_SLCD,
    .bpp    = 24,                            //R8G8B8
    .pinmd  = 0,

    .smart_config.rsply_cmd_high       = 0,
    .smart_config.csply_active_high    = 0,
    /* write graphic ram command, in word, for example 8-bit bus, write_gram_cmd=C3C2C1C0. */
    .smart_config.newcfg_fmt_conv =  0,
    .smart_config.clkply_active_rising = 1,
    .smart_config.data_times = 2,
    .smart_config.write_gram_cmd = truly_cmd_buf,
    .smart_config.length_cmd = ARRAY_SIZEtruly_cmd_buf),
    .smart_config.bus_width = 8,                                    //总线8位的
    .smart_config.length_data_table =  ARRAY_SIZEili9335_data_table),
    .smart_config.data_table = ili9335_data_table,
    .dither_enable = 1,
};

//新屏的初始化参数表
static struct smart_lcd_data_table New_ili9335_data_table[] = {
   {SMART_CONFIG_CMD,0x11},
       {SMART_CONFIG_UDELAY,120000},    //Sleep out
      {SMART_CONFIG_CMD,0x36},                //控制
    {SMART_CONFIG_DATA,0x00},
        
         {SMART_CONFIG_CMD,0x21},    //0x13显示不反转 ,21h 反显
         
         
    {SMART_CONFIG_CMD,0x3A},
    {SMART_CONFIG_DATA,0x05},

    {SMART_CONFIG_CMD,0x2A},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0xEF},

    {SMART_CONFIG_CMD,0x2B},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x01},
    {SMART_CONFIG_DATA,0x3F},

    {SMART_CONFIG_CMD,0xB2},        //前后肩
    {SMART_CONFIG_DATA,0x0C},
    {SMART_CONFIG_DATA,0x0C},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x33},
    {SMART_CONFIG_DATA,0x33},

    {SMART_CONFIG_CMD,0xB7},     //VGH VGL
    {SMART_CONFIG_DATA,0x35},

    {SMART_CONFIG_CMD,0xBB},     //VCOM 
    {SMART_CONFIG_DATA,0x1E},

    {SMART_CONFIG_CMD,0xC0},      //LCM
    {SMART_CONFIG_DATA,0x2C},

    {SMART_CONFIG_CMD,0xC2},
    {SMART_CONFIG_DATA,0x01},

    {SMART_CONFIG_CMD,0xC3},     //VRH vcom+vcom offset+vdv) 
    {SMART_CONFIG_DATA,0x27},

    {SMART_CONFIG_CMD,0xC4},     //vdv
    {SMART_CONFIG_DATA,0x20},

    {SMART_CONFIG_CMD,0xC6},        //帧率
    {SMART_CONFIG_DATA,0x0F},

    {SMART_CONFIG_CMD,0xD0},        //功率控制模式   
    {SMART_CONFIG_DATA,0xA4},
    {SMART_CONFIG_DATA,0xA1},

    {SMART_CONFIG_CMD,0xE0},        //正GAMMA 
    {SMART_CONFIG_DATA,0xD0},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x05},
    {SMART_CONFIG_DATA,0x03},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x07},
    {SMART_CONFIG_DATA,0x3F},
    {SMART_CONFIG_DATA,0x55},
    {SMART_CONFIG_DATA,0x50},
    {SMART_CONFIG_DATA,0x09},
    {SMART_CONFIG_DATA,0x14},
    {SMART_CONFIG_DATA,0x15},
    {SMART_CONFIG_DATA,0x22},
    {SMART_CONFIG_DATA,0x25},

    {SMART_CONFIG_CMD,0xE1},    //负GAMMA
    {SMART_CONFIG_DATA,0xD0},
    {SMART_CONFIG_DATA,0x00},
    {SMART_CONFIG_DATA,0x05},
    {SMART_CONFIG_DATA,0x03},
    {SMART_CONFIG_DATA,0x02},
    {SMART_CONFIG_DATA,0x07},
    {SMART_CONFIG_DATA,0x3F},
    {SMART_CONFIG_DATA,0x55},
    {SMART_CONFIG_DATA,0x54},
    {SMART_CONFIG_DATA,0x0C},
    {SMART_CONFIG_DATA,0x18},
    {SMART_CONFIG_DATA,0x14},
    {SMART_CONFIG_DATA,0x22},
    {SMART_CONFIG_DATA,0x25},

    {SMART_CONFIG_CMD,0x11},    // sleep out
    {SMART_CONFIG_UDELAY,120000},

    {SMART_CONFIG_CMD,0x29},//Display On
    {SMART_CONFIG_UDELAY,20000},
};
unsigned long New_truly_cmd_buf[]= {
     0x2C2C2C2C,
};


void switch_lcd_Newvoid)              //切换为ST7789V
{
    jzfb1_init_data.smart_config.data_table = New_ili9335_data_table;
    jzfb1_init_data.smart_config.length_data_table =  ARRAY_SIZENew_ili9335_data_table);
    jzfb1_init_data.smart_config.write_gram_cmd = New_truly_cmd_buf; 
}
//... ...

查看jz_lcd_v13.c调用顺序

从uboot启动时,调用board_init_r)函数开始:

 -> board_init_r)
         -> stdio_init)
                  -> drv_lcd_init)                //初始化硬件LCD
                  -> drv_video_init)       　　    //绘制log

其中drv_lcd_init)中调用顺序为:

 -> drv_lcd_init)
          -> lcd_init)
             -> lcd_ctrl_init)                 // 位于driversvideojz_lcdJz_lcd_v13.c

所以,接下来,我们便来修改jz_lcd_v13.c,让uboot在初始化LCD之前,读LCD的ID,是否需要切换新屏参数

 

修改jz_lcd_v13.c

由于X1000的SLCD控制寄存器只能向LCD写命令/数据，没有读数据的寄存器,所以我们便需要使用GPIO来模拟时序,读出ID来

参考ST7789V数据手册,找到ID命令为04h:

参考ST7789V数据手册,找到读写8080时序图:

接下来开始改代码: 

//添加下面函数,通过GPIO模拟LCD寄存器,来实现读ID
void  gpio_setfuncunsigned int gpioPort,enum gpio_function fun)
{

    enum gpio_port port; 
    
    switchgpioPort /32))
    {
        case 0:    port = GPIO_PORT_A; break;
        case 1:    port = GPIO_PORT_B; break;
        case 2:    port = GPIO_PORT_C; break;
        case 3:    port = GPIO_PORT_D; break;
               default:
               port = GPIO_NR_PORTS;   break;
    }
    gpio_set_funcport, fun, 1<< gpioPort % 32));

    iffun == GPIO_OUTPUT0||fun == GPIO_OUTPUT1)　　
    {
      iffun == GPIO_OUTPUT0)
        gpio_direction_outputgpioPort, 0);     
      else
          gpio_direction_outputgpioPort, 1);      
     }
}


static void write_SLCD_CDint isCOMD,unsigned int value) //写命令/数据
{

    #define  SLCD_DC    20
    #define  SLCD_WR   17
    #define  SLCD_RD    16
    #define  SLCD_CS     18
    
    int i;
    gpio_direction_outputGPIO_PBSLCD_CS), 1);     
    
    for i=0;i<8;i++)
     {
           gpio_setfuncGPIO_PAi),GPIO_OUTPUT0);
         gpio_direction_outputGPIO_PAi), value>>i)&0x01);     
    }
    
    
    mdelay10);
    
    ifisCOMD!=0)    //如果是写命令,则拉低DC脚
    {
        gpio_direction_outputGPIO_PBSLCD_DC), 0);    
    }
    else
    {
        gpio_direction_outputGPIO_PBSLCD_DC),1);    
    }
    gpio_direction_outputGPIO_PBSLCD_WR), 0);     
    gpio_direction_outputGPIO_PBSLCD_RD), 1);     

    gpio_direction_outputGPIO_PBSLCD_CS), 0);     
    
    
    mdelay4);
    gpio_direction_outputGPIO_PBSLCD_WR), 1);     
    
    mdelay7);
}

static unsigned int read_SLCD_DATAvoid)   //读数据
{

    #define  SLCD_DC    20
    #define  SLCD_WR   17
    #define  SLCD_RD    16
    #define  SLCD_CS     18
    
    int i;
    int ret=0;

    gpio_direction_outputGPIO_PBSLCD_CS), 1);     //取消片选
    
    for i=0;i<8;i++)        //将data脚设为输入脚
     {
           gpio_setfuncGPIO_PAi),GPIO_INPUT); 
    }
    
    gpio_direction_outputGPIO_PBSLCD_DC), 1);     
    gpio_direction_outputGPIO_PBSLCD_WR), 1);     
    gpio_direction_outputGPIO_PBSLCD_RD), 0);     

    gpio_direction_outputGPIO_PBSLCD_CS), 0);     //选中片选
    
    mdelay4);
    gpio_direction_outputGPIO_PBSLCD_RD), 1);     
    for i=0;i<8;i++)
    ret|=gpio_get_valueGPIO_PAi))<<i);
    mdelay7);
    
    return ret;
}

static void lcd_func_initint isRestore)
 {
    int i,n;
    #define  SLCD_DC    20
    #define  SLCD_WR   17
    #define  SLCD_RD    16
    #define  SLCD_TE     19            //input
     #define  SLCD_CS     18
       
 
      
     ifisRestore)                                //恢复管脚为LCD控制寄存器
     {
        fori=0;i<8;i++)
         gpio_setfuncGPIO_PAi),GPIO_FUNC_1);

        gpio_setfuncGPIO_PBSLCD_DC),GPIO_FUNC_1);
        gpio_setfuncGPIO_PBSLCD_WR),GPIO_FUNC_1);
        gpio_setfuncGPIO_PBSLCD_RD),GPIO_FUNC_1);
        gpio_setfuncGPIO_PBSLCD_TE),GPIO_FUNC_1);
         gpio_setfuncGPIO_PBSLCD_CS),GPIO_FUNC_1);
        
    }
    else　　　　　　　　　　　　　　　　　　　　　　　　　　//设置为普通IO管脚
    {
        fori=0;i<8;i++)
         gpio_setfuncGPIO_PAi),GPIO_OUTPUT0);

        gpio_setfuncGPIO_PBSLCD_DC),GPIO_OUTPUT0);
        gpio_setfuncGPIO_PBSLCD_WR),GPIO_OUTPUT0);
        gpio_setfuncGPIO_PBSLCD_RD),GPIO_OUTPUT0);
        gpio_setfuncGPIO_PBSLCD_TE),GPIO_INPUT);
         gpio_setfuncGPIO_PBSLCD_CS),GPIO_OUTPUT0);

            
          
    }

      mdelay200);
}
    
static u8 Read_ID_isNewLcdvoid)
{
    #define  SLCD_DC    20
    #define  SLCD_WR   17
    #define  SLCD_RD    16
    #define  SLCD_TE     19            //input
     #define  SLCD_CS     18
    
    u8 ret = 0;
    u8 IDH,IDL;
    lcd_func_init0);   //设置LCD相关的引脚,设置为普通IO脚
    
    write_SLCD_CD1,0x04);　　//写入0x04命令

    IDH = read_SLCD_DATA);
    IDL = read_SLCD_DATA);
    
    printf"Read ID: 0x%X 0x%X
",IDH,IDL);
    IDH = read_SLCD_DATA);
    IDL = read_SLCD_DATA);
    
    printf"Read ID: 0x%X 0x%X
",IDH,IDL);         
    
    ifIDL!=0x52)          //如果值!=0X52,则表示是旧屏ili9335
    {
        ret =1;
    }
     
    lcd_func_init1);    //将lcd相关引脚配置为LCD控制脚
    mdelay10);
    
    return ret;
}


extern void switch_lcd_Newvoid) ;
static int lcd_type_isNew=0; 
void set_lcd_type_from_cmdlinevoid)   //设置bootargs,向内核传递lcd_type参数
{
    iflcd_type_isNew)    
    {
        run_command"set  bootargs "CONFIG_BOOTARGS" lcd_type=new ", 0);
    }

}

//在lcd_ctrl_init)函数里添加读ID函数
void lcd_ctrl_initvoid *lcd_base)
{
          ifRead_ID_isNewLcd)==0)        //读ID,检测是否是新屏
    {
        printf"Read_ID_isNewLcd=0
"); 
        switch_lcd_New);     //调用Lcd-ili9335_240x320.c的切换新屏参数的函数
        
        lcd_type_isNew=1;    
    }  
   //... ... 后面的代码不需要修改,因为后面便会根据LCD初始化参数表.来初始化LCD
}

上面的set_lcd_type_from_cmdline)函数需要在后面调用main_loop)的时候之前被调用,所以还需要修改board_init_r)函数archmipslibBoard.c ).

然后装上旧屏ili9335,启动uboot,查看读的屏幕ID,屏幕显示正常:

然后换为新屏,启动uboot,查看读的ID信息,log显示正常:

启动内核时,也可以看到传递给内核bootargs有我们新添的参数:

然后在内核中,便通过新参数再次设置屏参数表即可.

 

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独自遨游何稽首 揭天掀地慰生平

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