2440+30.4 LCD 移植 （八）

说明：本篇博客 参考tq linux 移植手册中的内容，只是自己学习过程中的记录。


1.简化LCD时钟计算方法

     修改 “drivers/video/s3c2410fb.c”

static void s3c2410fb_activate_var(struct fb_info *info)
{
    struct s3c2410fb_info *fbi = info->par;
    void __iomem *regs = fbi->io;

    int type = fbi->regs.lcdcon1 & S3C2410_LCDCON1_TFT;
添加：
    struct s3c2410fb_mach_info *mach_info = fbi->dev->platform_data;
    struct s3c2410fb_display *default_display = mach_info->displays +
                         mach_info->default_display;
结束
    struct fb_var_screeninfo *var = &info->var;
    int clkdiv = s3c2410fb_calc_pixclk(fbi, var->pixclock) / 2;

    dprintk("%s: var->xres = %d\n", __func__, var->xres);
    dprintk("%s: var->yres = %d\n", __func__, var->yres);
    dprintk("%s: var->bpp = %d\n", __func__, var->bits_per_pixel);

    if (type == S3C2410_LCDCON1_TFT) {
        s3c2410fb_calculate_tft_lcd_regs(info, &fbi->regs);
        --clkdiv;
        if (clkdiv < 0)
            clkdiv = 0;
    } else {
        s3c2410fb_calculate_stn_lcd_regs(info, &fbi->regs);
        if (clkdiv < 2)
            clkdiv = 2;
    }

//    fbi->regs.lcdcon1 |= S3C2410_LCDCON1_CLKVAL(clkdiv);
修改为       fbi->regs.lcdcon1 |= S3C2410_LCDCON1_CLKVAL(default_display->setclkval);

2.完成了这部分修改后，我们在时c2410fb_display 结构体中添加了一个 setclkval 变量，那么我们需要在该结构体的院校中添加上该变量，修改“arch/arm/mach-s3c2410/include/fb.h”

struct s3c2410fb_display {
    /* LCD type */
    unsigned type;

    /* Screen size */
    unsigned short width;
    unsigned short height;

    /* Screen info */
    unsigned short xres;
    unsigned short yres;
    unsigned short bpp;

    unsigned pixclock;        /* pixclock in picoseconds */
##  /* 新加入的项，目的是减少计算pixclock的复杂度*/
    unsigned setclkval;        /* clkval */

    unsigned short left_margin; /* value in pixels (TFT) or HCLKs (STN) */

3.修改LCD 各个参数，注意：添加上刚刚添加的那个变量 setclkval 的赋值
  修改 "arch/arm/mach-s3c2440/mach-smdk2440.c"

/* LCD driver info */

static struct s3c2410fb_display smdk2440_lcd_cfg __initdata = {

    .lcdcon5    = S3C2410_LCDCON5_FRM565 |
             S3C2410_LCDCON5_INVVLINE |
             S3C2410_LCDCON5_INVVFRAME |
             S3C2410_LCDCON5_PWREN |
             S3C2410_LCDCON5_HWSWP,

        .type        = S3C2410_LCDCON1_TFT,

#if    defined(CONFIG_FB_S3C24X0_W320240)
    .width        = 320,
    .height        = 240,

    .pixclock        = 80000, /* HCLK 100 MHz, divisor 3 */

/* 新加入的项，目的是减少计算pixclock的复杂度*/
    .setclkval        = 0x3,

    .xres        = 320,
    .yres        = 240,
    .bpp        = 16,
    .left_margin    = 28,    /* for HFPD*/
    .right_margin    = 24,    /* for HBPD*/
    .hsync_len    = 42,    /* for HSPW*/
    .upper_margin    = 6,    /* for VFPD*/
    .lower_margin    = 2,    /* for VBPD*/
    .vsync_len    = 12,    /* for VSPW*/

#endif
};

4.修改 drivers/video/Kconfig

config FB_S3C24X0   修改
    tristate "S3C2410 LCD framebuffer support"

   depends on FB && ARCH_S3C2410
    select FB_CFB_FILLRECT
    select FB_CFB_COPYAREA
    select FB_CFB_IMAGEBLIT
    ---help---
     Frame buffer driver for the built-in LCD controller in the Samsung
     S3C2410 processor.

     This driver is also available as a module ( = code which can be
     inserted and removed from the running kernel whenever you want). The
     module will be called s3c2410fb. If you want to compile it as a module,
     say M here and read <file:Documentation/kbuild/modules.txt>.

     If unsure, say N.

choice            添加
    prompt "LCD select"
    depends on FB_S3C24X0
    help
     S3C24x0 LCD size select

config FB_S3C24X0_W320240
    boolean "3.5 inch 320x240 WanXin LCD"
    depends on FB_S3C24X0
    help
     3.5 inch 320x240 WanXin LCD

endchoice

config FB_S3C2410_DEBUG
    bool "S3C2410 lcd debug messages"
    depends on FB_S3C24X0   #修改
    help
     Turn on debugging messages. Note that you can set/unset at run time
     through sysfs

4.修改 drivers/video/Makefile

obj-$(CONFIG_FB_IMX) += imxfb.o

obj-$(CONFIG_FB_S3C)         += s3c-fb.o

obj-$(CONFIG_FB_S3C24X0)     += s3c2410fb.o   #因为Kconifg 修改为 CONFIG_FB_S3C24X0，所以这里修改

obj-$(CONFIG_FB_FSL_DIU)     += fsl-diu-fb.o

5.制作 linux 的开机 logo
  有几点需要注意：1.使用320*240 像素的 bmp 图片，
                  2.我用别的像素制作的图片，当下载到板子后，出现，黑、白、红、绿交替闪烁，
                    没有出现预期的图片           
   上传自己制作好的图片.ppm   logo_linux_tft320240_clut224.ppm   


6.支持LCD设置
   复制 logo_linux_tft320240_clut224.ppm 到 drivers/video/logo

   修改drivers/video/logo/Kconfig

config LOGO_LINUX_CLUT224
    bool "Standard 224-color Linux logo"
    default y

添加
config LOGO_LINUX_TFT320240_CLUT224
    bool "Standard 224-color Linux logo for 320X240"
    depends on LOGO && FB_S3C24X0_S320240 || FB_S3C24X0_W320240
    default y

结束

   修改drives/video/logo/Makefile

obj-$(CONFIG_LOGO_LINUX_CLUT224)     += logo_linux_clut224.o

添加
obj-$(CONFIG_LOGO_LINUX_TFT320240_CLUT224)        += logo_linux_tft320240_clut224.o

   修改 drivers/video/logo/logo.c

extern const struct linux_logo logo_linux_clut224;

extern const struct linux_logo logo_linux_tft320240_clut224;

#ifdef CONFIG_LOGO_LINUX_CLUT224
        /* Generic Linux logo */
        logo = &logo_linux_clut224;
#endif


#ifdef CONFIG_LOGO_LINUX_TFT320240_CLUT224
        /* Generic Linux logo */
        logo = &logo_linux_tft320240_clut224;
#endif

7.配置内核

Device Drivers -->
    Graphics support  __>
       <*>Support for frame buffer devices ->
              [*] Enable firmware EDID
              [*] Enable Video mode handling dhelpers
                         ****frame buffer hardware dirvers***

              <*> S3C24X0 LCD framebufer support   注意这个就是在 Kconfig中 drivers/video/
                        LCD select 3.5 inch 320*240
              <*> Frambuffer console support
       [*]bootup logo ->               注意：drivers/video/logo/Kconfig
               [*]  standard 224-color linux logo for 320*240

8.ok 了