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测试平台： Mini2440 Sonic X35 Lcd Linux-2.6.29 u-boot 2008.10
说起这块屏幕，可真是费劲，LCD原理图跟别人的好多不一样，时序图也有很大的差别，LCD上vline 和vframe根本没有，只能通过pci和mck两个时钟进行设置；
还一个就是：不知道是uboot的原因还是友善官网提供的原理图有错 ，vden必须反转才能正常！！
#include#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct lcd_regs{ unsigned long lcdcon1; unsigned long lcdcon2; unsigned long lcdcon3; unsigned long lcdcon4; unsigned long lcdcon5; unsigned long lcdsaddr1; unsigned long lcdsaddr2; unsigned long lcdsaddr3; unsigned long redlut; unsigned long greenlut; unsigned long bluelut; unsigned long reserved[9]; unsigned long dithmode; unsigned long tpal; unsigned long lcdintpnd; unsigned long lcdsrcpnd; unsigned long lcdintmsk; unsigned long lpcsel;};static volatile struct lcd_regs *lcd_regs_base;static struct fb_info *fb_x35;static volatile unsigned long *gpbcon;static volatile unsigned long *gpbdat;static volatile unsigned long *gpccon;static volatile unsigned long *gpdcon;static volatile unsigned long *gpgcon;static u32 pseudo_palette[16];static inline unsigned int chan_to_field(unsigned int chan, struct fb_bitfield* bf){ chan &= 0xffff; chan >>= 16 - bf->length; return chan << bf->offset;}//设置颜色static int x35_setcolreg(unsigned int regno, unsigned int red, unsigned int green, unsigned int blue, unsigned int transp, struct fb_info *info){ unsigned int val; if (regno > 16) return 1; val = chan_to_field(red, &info->var.red); val |= chan_to_field(green, &info->var.green); val |= chan_to_field(blue, &info->var.blue); pseudo_palette[regno] = val; return 0;}static struct fb_ops mini_fb_ops = { .owner = THIS_MODULE, .fb_setcolreg = x35_setcolreg, .fb_fillrect = cfb_fillrect, .fb_copyarea = cfb_copyarea, .fb_imageblit = cfb_imageblit,};static int lcd_init(void){ //1)分配一个fb_info fb_x35 = framebuffer_alloc(0, NULL); //2)填充fb_info结构 // 1 设置固定参数 // 2 设置可变参数 // 3 设置操作函数 // 4 其他的设置 strcpy(fb_x35->fix.id, "mylcd"); fb_x35->fix.smem_len = 240 * 320 * 32 / 8; // frambuffer的大小 fb_x35->fix.type = FB_TYPE_PACKED_PIXELS;//扫描方式，以像素点扫描 非隔行扫描 fb_x35->fix.visual = FB_VISUAL_TRUECOLOR; //色阶 真彩色 fb_x35->fix.line_length = 240 * 4; fb_x35->var.xres = 240; fb_x35->var.yres = 320; fb_x35->var.xres_virtual = 240; fb_x35->var.yres_virtual = 320; fb_x35->var.bits_per_pixel = 32; //每个像素点占有的字节数 //颜色放置的方式，这里是真彩色为 8:8:8,每种颜色占用8位 fb_x35->var.red.offset = 16; fb_x35->var.red.length = 8; fb_x35->var.blue.offset = 8; fb_x35->var.blue.length = 8; fb_x35->var.green.offset = 0; fb_x35->var.green.length = 8; fb_x35->var.activate = FB_ACTIVATE_NOW; //设置颜色立即生效 //设置操作函数 fb_x35->fbops = &mini_fb_ops; fb_x35->pseudo_palette = pseudo_palette; //调色板 fb_x35->screen_size = 240 * 320 * 32 / 8; //屏幕尺寸的大小 //3)设置硬件，驱动lcd // 1 设置lcd引脚可用 // 2 设置lcd控制器寄存器 // 3 设置其他的 gpbcon = ioremap(0x56000010, 8); gpbdat = gpbcon+1; gpccon = ioremap(0x5600020, 4); gpdcon = ioremap(0x5600030, 4); gpgcon = ioremap(0x5600060, 4); *gpccon = 0xaaaaaaaa; *gpdcon = 0xaaaaaaaa; *gpgcon |= (0x3 << (4 * 2)); //lcd_pwren lcd电源引脚 lcd_regs_base = ioremap(0x4d000000, sizeof(struct lcd_regs)); lcd_regs_base->lcdcon1 = (9 << 8) | (3 << 5) | (0xd << 1); lcd_regs_base->lcdcon2 = (8 << 24) | (319 << 14) | (4 << 6) | (9 << 0); lcd_regs_base->lcdcon3 = (15 << 19) | (239 << 8) | (16 << 0) ; lcd_regs_base->lcdcon4 = 5; lcd_regs_base->lcdcon5 = (0 << 12) | (0 << 10) | (1<<6) | (0 << 1) | (0 << 0) ; //vsync swap set error //分配显存，将显存地址告诉framebuffer fb_x35->screen_base = dma_alloc_writecombine(NULL, fb_x35->fix.smem_len, &(fb_x35->fix.smem_start), GFP_KERNEL);//fb_x35->fix.smem_start = xxx; /* 显存的物理地址 */ lcd_regs_base->lcdsaddr1 = (fb_x35->fix.smem_start >> 1) & (~(3 << 30)); //[31~0]=0b00xx xxxx ... 30误写成20 lcd_regs_base->lcdsaddr2 = ((fb_x35->fix.smem_start + fb_x35->fix.smem_len) >> 1) & 0x1fffff; lcd_regs_base->lcdsaddr3 = (0 << 11) | ((240 * 32 / 16) << 0); //行的长度有错 //启动lcd lcd_regs_base->lcdcon1 |= (1 << 0); lcd_regs_base->lcdcon5 |= (1 << 3); /* MINI2440的背光电路也是通过LCD_PWREN来控制的, 不需要单独的背光引脚 */ //4)注册framebuffer register_framebuffer(fb_x35); return 0;}static void lcd_exit(void){ //注销framebuffer结构 //释放分配的frambuffer显存 //关闭lcd控制器以及电源 //取消映射地址 //释放framebuffer结构 unregister_framebuffer(fb_x35); lcd_regs_base->lcdcon1 &= ~(1 << 0); lcd_regs_base->lcdcon5 &= ~(1 << 3); dma_free_writecombine(NULL, fb_x35->fix.smem_len, fb_x35->screen_base, fb_x35->fix.smem_start); iounmap(lcd_regs_base); iounmap(gpccon); iounmap(gpdcon); iounmap(gpgcon); framebuffer_release(fb_x35);}module_init(lcd_init);module_exit(lcd_exit);MODULE_LICENSE("GPL");MODULE_AUTHOR("LCL");
1. make menuconfig去掉原来的驱动程序 -> Device Drivers -> Graphics support <M> S3C2410 LCD framebuffer support
2. make uImage make modules
3. 使用新的uImage启动开发板:
4. 先将之前module下编译出来的几个文件拷到开发板上cfbcopyarea.ko cfbfillrect.ko cfbimgblt.ko(/drivers/video/*)
5.
insmod cfbcopyarea.ko insmod cfbfillrect.ko insmod cfbimgblt.ko insmod lcd.ko
6.
echo hello > /dev/tty1 // 可以在LCD上看见hello cat lcd.ko > /dev/fb0 // 花屏
当然也可以测试其他的，这里不进行描述。
注意：里面的图像调整其实还不是最关键的，关键是vden不翻转 就没有图像，我调试过好多次，幸亏论坛网友热心帮助，才点亮lcd。
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