内核启动后，lcd显示logo失败

针对-s5pv210，但对其他平台也使用lcd显示logo失败，若显示成功默认的logo是一只企鹅，但是串口打印“Start display and show logo”，但是LCD屏没有显示   

[ 0.833071] s3cfb s3cfb: [fb2] dma: 0x465ab000, cpu: 0xe1000000, size: 0x005dc000[ 0.845112] FIMD src sclk = 166750000[ 0.965701] s3cfb s3cfb: registered successfully[ 0.965744] Start display and show logo

 原因：LCD驱动有问题。第一步：在arch/arm/mach-s5pv210/mach-smdkc110.c当中，约712行，将之前的LCD初始化删掉，并修改如下:

#ifdef CONFIG_FB_S3C_LTE480WVstatic struct s3cfb_lcd wvga_s70 = {   .width = 800,  .height = 480,  .p_width = 154,  .p_height = 96,  .bpp = 32,  .freq = 65,   .timing = {    .h_fp = 80,    .h_bp = 36,    .h_sw = 10,    .v_fp = 22,    .v_fpe = 1,    .v_bp = 15,    .v_bpe = 1,    .v_sw = 8,  },  .polarity = {    .rise_vclk = 0,    .inv_hsync = 1,    .inv_vsync = 1,    .inv_vden = 0,  },}; static void lcd_cfg_gpio(struct platform_device *pdev){ int i;  for (i = 0; i < 8; i++) {  s3c_gpio_cfgpin(S5PV210_GPF0(i), S3C_GPIO_SFN(2));  s3c_gpio_setpull(S5PV210_GPF0(i), S3C_GPIO_PULL_NONE); }  for (i = 0; i < 8; i++) {  s3c_gpio_cfgpin(S5PV210_GPF1(i), S3C_GPIO_SFN(2));  s3c_gpio_setpull(S5PV210_GPF1(i), S3C_GPIO_PULL_NONE); }  for (i = 0; i < 8; i++) {  s3c_gpio_cfgpin(S5PV210_GPF2(i), S3C_GPIO_SFN(2));  s3c_gpio_setpull(S5PV210_GPF2(i), S3C_GPIO_PULL_NONE); }  for (i = 0; i < 4; i++) {  s3c_gpio_cfgpin(S5PV210_GPF3(i), S3C_GPIO_SFN(2));  s3c_gpio_setpull(S5PV210_GPF3(i), S3C_GPIO_PULL_NONE); }  /* mDNIe SEL: why we shall write 0x2 ? */ writel(0x2, S5P_MDNIE_SEL);  /* drive strength to max */ writel(0xaaaaaaaa, S5PV210_GPF0_BASE + 0xc); writel(0xaaaaaaaa, S5PV210_GPF1_BASE + 0xc); writel(0xaaaaaaaa, S5PV210_GPF2_BASE + 0xc); writel(0x000000aa, S5PV210_GPF3_BASE + 0xc);} #define S5PV210_GPD_0_0_TOUT_0 (0x2)#define S5PV210_GPD_0_1_TOUT_1 (0x2 << 4)#define S5PV210_GPD_0_2_TOUT_2 (0x2 << 8)#define S5PV210_GPD_0_3_TOUT_3 (0x2 << 12)static int lcd_backlight_on(struct platform_device *pdev){ int err;  err = gpio_request(S5PV210_GPD0(3), "GPD0");  if (err) {  printk(KERN_ERR "failed to request GPD0 for "   "lcd backlight control\n");  return err; }  gpio_direction_output(S5PV210_GPD0(3), 1);  s3c_gpio_cfgpin(S5PV210_GPD0(3), S5PV210_GPD_0_3_TOUT_3);  gpio_free(S5PV210_GPD0(3)); return 0;} static int lcd_backlight_off(struct platform_device *pdev, int onoff){ int err;  err = gpio_request(S5PV210_GPD0(3), "GPD0");  if (err) {  printk(KERN_ERR "failed to request GPD0 for "    "lcd backlight control\n");  return err; }  gpio_direction_output(S5PV210_GPD0(3), 0); gpio_free(S5PV210_GPD0(3)); return 0;} static int lcd_reset_lcd(struct platform_device *pdev){ int err;  err = gpio_request(S5PV210_GPH0(6), "GPH0"); if (err) {  printk(KERN_ERR "failed to request GPH0 for "    "lcd reset control\n");  return err; }  gpio_direction_output(S5PV210_GPH0(6), 1); mdelay(100);  gpio_set_value(S5PV210_GPH0(6), 0); mdelay(10);  gpio_set_value(S5PV210_GPH0(6), 1); mdelay(10);  gpio_free(S5PV210_GPH0(6));  return 0;} static struct s3c_platform_fb lte480wv_fb_data __initdata = { .hw_ver = 0x62, .nr_wins = 5, .default_win = CONFIG_FB_S3C_DEFAULT_WINDOW, .swap = FB_SWAP_WORD | FB_SWAP_HWORD,  .lcd = &wvga_s70, .cfg_gpio = lcd_cfg_gpio, .backlight_on = lcd_backlight_on, .backlight_onoff = lcd_backlight_off, .reset_lcd = lcd_reset_lcd,};#endif

 第二步：使用make menuconfig，去配置当前显示的windows，请配置为windows0   

Device Drivers　　-->Graphics support 　　--> Support for frame buffer devices  　　--> (2)  Default Window (0-4) 

 

 修改为

Device Drivers　　-->Graphics support  　 --> Support for frame buffer devices  　　--> (0)  Default Window (0-4)

 

 

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原标题：内核启动后，lcd显示logo失败

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