FL2440的U-boot-2010.09移植（七）LCD的支持

一、LCD时序配置

     fl2440开发板的LCD是3.5寸屏型号是WXCAT35-TG3#001，这是一款320x240分辨率的TFT LCD屏，先来了解一下TFT LCD的时序如下：

图1 TFT LCD时序

（1）VSYNC信号来一个脉冲时，表示一帧的开始

（2） VSPW表示VSYNC信号的脉冲宽度为（VSPW+1）个HSYNC信号周期，即（VSPW+1）行，这（VSPW+1）行的数据无效。

（3）VSYNC信号脉冲之后，还要经过（VBPD+1）个（HSYNC）信号周期，有效的行数据才出现。所以，在VSYNC信号有效之后，总共还要经过（VSPW+1+VBPD+1）个无效行，

（4）随后连续发出（LINEVAL+1）行的有效数据

（5）最后是（VFPD+1）个无效行，完整的一帧结束，紧接着就是下一帧的数据了（即下一个VSYNC信号）。

（6）HSYNC信号有效时，表示一行数据的开始

（7） HSPW表示HSYNC信号的脉冲宽度为（HSPW+1）个VCLK信号周期，即（HSPW+1）个像素，这（HSPW+1）个像素的数据无效。

（8）HSYNC信号脉冲之后，还要经过（HBPD+1）个VCLK信号周期，有效的像素数据才会出现。所以，在HSYNC信号有效之后，总共还要经过（HSPW + 1 + HBPD + 1）个无效的像素，第一个有效像素才出现。

（9）随后即连续发出（HOZVAL+1）个像素的有效数据。

（10）最后是（HFPD+1）个无效的像素，完整的一行结束，紧接着就是下一行的数据了（即下一个HSYNC信号）。

TFT LCD的正常工作主要需要配置S3C2440的寄存器LCDCON1~LCDCON5。

二、u-boot支持LCD的配置工作

首先要添加一个文件，driver/video/s3c2410_fb.c，其内容为：

 /*
  * (C) Copyright 2006 by OpenMoko, Inc.
  * Author: Harald Welte <[email protected]>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */
 #include <common.h>

 #if defined(CONFIG_VIDEO_S3C2410)||defined(CONFIG_VIDEO_S3C2440)

 #include <video_fb.h>
 #include <asm/arch/s3c2410.h>

 #include "videomodes.h"
 /*
  * Export Graphic Device
  */
 static GraphicDevice smi;

 #define VIDEO_MEM_SIZE  0x200000        /* 240x320x16bit = 0x25800 bytes */

 extern void board_video_init( GraphicDevice *pGD);
 /*
  * Add by yanghao
  */
 /*******************************************************************************
  *
  * Init video chip with common Linux graphic modes (lilo)
  */
 void *video_hw_init (void)
 {
     struct s3c24x0_lcd * const lcd = s3c24x0_get_base_lcd();
     GraphicDevice *pGD = (GraphicDevice *)&smi;
     int videomode;
     unsigned long t1, hsynch, vsynch;
     char *penv;
     int tmp, i, bits_per_pixel;
     struct ctfb_res_modes *res_mode;
     struct ctfb_res_modes var_mode;
 //    unsigned char videoout;

     /* Search for video chip */
     printf("Video: ");
     tmp = 0;

          videomode = CONFIG_SYS_DEFAULT_VIDEO_MODE;
          /* get video mode via environment */
          if ((penv = getenv ("videomode")) != NULL) {
                  /* deceide if it is a string */
                  if (penv[0] <= '9') {
                          videomode = (int) simple_strtoul (penv, NULL, 16);
                          tmp = 1;
                  }
          } else {
                  tmp = 1;
          }
          if (tmp) {
                  /* parameter are vesa modes */
                  /* search params */
                  for (i = 0; i < VESA_MODES_COUNT; i++) {
                          if (vesa_modes[i].vesanr == videomode)
                                  break;
                  }
                  if (i == VESA_MODES_COUNT) {
                          printf ("no VESA Mode found, switching to mode 0x%x ", CONFIG_SYS_DEFAULT_VIDEO_MODE);
                          i = 0;
                 }
                  res_mode =
                          (struct ctfb_res_modes *) &res_mode_init[vesa_modes[i].
                                                                   resindex];
                  bits_per_pixel = vesa_modes[i].bits_per_pixel;
          } else {

                 res_mode = (struct ctfb_res_modes *) &var_mode;
                  bits_per_pixel = video_get_params (res_mode, penv);
          }

          /* calculate hsynch and vsynch freq (info only) */
          t1 = (res_mode->left_margin + res_mode->xres +
                res_mode->right_margin + res_mode->hsync_len) / 8;
          t1 *= 8;
          t1 *= res_mode->pixclock;
          t1 /= 1000;
          hsynch = 1000000000L / t1;
          t1 *=
                  (res_mode->upper_margin + res_mode->yres +
                   res_mode->lower_margin + res_mode->vsync_len);
          t1 /= 1000;
          vsynch = 1000000000L / t1;

          /* fill in Graphic device struct */
          sprintf (pGD->modeIdent, "%dx%dx%d %ldkHz %ldHz", res_mode->xres,
                   res_mode->yres, bits_per_pixel, (hsynch / 1000),
                   (vsynch / 1000));
          printf ("%s\n", pGD->modeIdent);
          pGD->winSizeX = res_mode->xres;
          pGD->winSizeY = res_mode->yres;
          pGD->plnSizeX = res_mode->xres;
          pGD->plnSizeY = res_mode->yres;

          switch (bits_per_pixel) {
          case 8:
                  pGD->gdfBytesPP = 1;
                  pGD->gdfIndex = GDF__8BIT_INDEX;
                  break;
          case 15:
                  pGD->gdfBytesPP = 2;
                  pGD->gdfIndex = GDF_15BIT_555RGB;
                  break;
          case 16:
                  pGD->gdfBytesPP = 2;
                  pGD->gdfIndex = GDF_16BIT_565RGB;
                  break;
          case 24:
                  pGD->gdfBytesPP = 3;
                  pGD->gdfIndex = GDF_24BIT_888RGB;
                  break;
          }

          /* statically configure settings */
         pGD->winSizeX = pGD->plnSizeX = 320;
          pGD->winSizeY = pGD->plnSizeY = 240;
          pGD->gdfBytesPP = 2;
          pGD->gdfIndex = GDF_16BIT_565RGB;

          pGD->frameAdrs = LCD_VIDEO_ADDR;
          pGD->memSize = VIDEO_MEM_SIZE;

          board_video_init(pGD);

          lcd->LCDSADDR1 = pGD->frameAdrs >> 1;

          /* This marks the end of the frame buffer. */
          lcd->LCDSADDR2 = (lcd->LCDSADDR1&0x1fffff) + (pGD->winSizeX+0) * pGD->winSizeY;
          lcd->LCDSADDR3 = (pGD->winSizeX & 0x7ff);

          /* Clear video memory */
          memset((void *)pGD->frameAdrs, 0, pGD->memSize);

          /* Enable  Display  */
          lcd->LCDCON1 |= 0x01;   /* ENVID = 1 */

          return ((void*)&smi);
  }
  #endif /* CONFIG_VIDEO_S3C2410 */

修改driver/video/videomodes.h文件第25行左右为：

 #ifndef CONFIG_SYS_DEFAULT_VIDEO_MODE
 //#define CONFIG_SYS_DEFAULT_VIDEO_MODE 0x301


 #define CONFIG_SYS_DEFAULT_VIDEO_MODE   0x211
 #endif

紧接着修改driver/video/videomodes.h第81行左右为：

 #define RES_MODE_1280x1024  5
 #define RES_MODE_240x320        6
 #define RES_MODES_COUNT     7

 #define VESA_MODES_COUNT 20

在driver/video/videomodes..c文件struct ctfb_vesa_modes vesa_modes定义中添加（第78行左右）本开发板LCD的相关配置：

 {0x211, RES_MODE_240x320, 16},

在driver/video/videomodes..c文件struct ctfb_res_modes res_mode_init定义中添加（第100行左右）本开发板LCD的相关配置：

 {320, 240, 158025, 58, 15, 3, 5, 8, 15, 0, FB_VMODE_NONINTERLACED},

紧接着修改driver/video/Makefile文件，在41行后添加：

 COBJS-$(CONFIG_VIDEO_S3C2440) += videomodes.o
 COBJS-$(CONFIG_VIDEO_S3C2440) += s3c2410_fb.o

最后，修改文件board/fl2440/fl2440.c，在文件最后添加：

 /*
  * Add by yanghao
  */
 #if defined(CONFIG_VIDEO_S3C2440)
 #define MVAL                   (13)
 #define MVAL_USED              (0)
 #define INVVDEN                (1)
 #define BSWP                   (0)
 #define HWSWP                  (1)
 //TFT 240320
 #define LCD_XSIZE_TFT_240320   (320)
 #define LCD_YSIZE_TFT_240320   (240)
 //TFT 240320
 #define HOZVAL_TFT_240320      (LCD_XSIZE_TFT_240320-1)
 #define LINEVAL_TFT_240320     (LCD_YSIZE_TFT_240320-1)
 //Timing parameter for WXCAT35-TG#001
 #define VBPD_240320            (3)
 #define VFPD_240320            (5)
 #define VSPW_240320            (15)
 #define HBPD_240320            (58)
 #define HFPD_240320            (15)
 #define HSPW_240320_WXCAT35    (8)//adjust the horizontal displacement of the screen


 #define CLKVAL_TFT_240320      (7)
 //FCLK = 405MHZ, HCLK = 101.25MHZ, VCLK=4602272HZ
 void board_video_init(GraphicDevice *pGD)
 {
     struct s3c24x0_lcd * const lcd = s3c24x0_get_base_lcd();
    /*Configuration for fl2440*/
     lcd->LCDCON1 = (CLKVAL_TFT_240320 <<8)|(MVAL_USED <<7)|(3<<5)|(12<<1)|0;
    lcd->LCDCON2 = (VBPD_240320<<24)|(LINEVAL_TFT_240320<<14)|(VFPD_240320<<6)|(VSPW_240320);
    lcd->LCDCON3 = (HBPD_240320<<19)|(HOZVAL_TFT_240320<<8)|(HFPD_240320);
    lcd->LCDCON4 = (MVAL<<8)|(HSPW_240320_WXCAT35);
    lcd->LCDCON5 = (1<<11)|(1<<9)|(1<<8)|(1<<3)|(BSWP<<1)|(HWSWP);
    lcd->LPCSEL = 0x00000000;
 }
 #endif /*CONFIG_VIDEO_S3C2440*/

最后还需要在开发板配置文件中添加LCD屏支持的宏定义，修改文件include/configs/fl2440.h文件，在文件中添加：

 #include <video_fb.h> //头文件定义处添加

 /*****************add by yanghao support LCD文件末尾处添加********************/
 /*LCD support*/
 #define CONFIG_VIDEO_S3C2440     1
 #define CONFIG_VIDEO_LOGO        1
 #define CONFIG_VIDEO_BMP_LOGO           1
 #define VIDEO_FB_16BPP_WORD_SWAP       1
 #define CONFIG_CMD_BMP                  1
 //#define CONFIG_LCD               1
 #define CONFIG_VIDEO               1
 #define CONFIG_CFB_CONSOLE       1
 #define CFG_CONSOLE_INFO_QUIET        //support display of console information at boot

 #define LCD_VIDEO_ADDR          0x33b00000

 /*for PC-keyboard*/
 #define VIDEO_KBD_INIT_FCT      0
 /*for PC-keyboard*/

 #define VIDEO_TSTC_FCT          serial_tstc
 #define VIDEO_GETC_FCT          serial_getc

 #define CONFIG_SERIAL_MULTI     1
 /*LCD support*/

重新上电后，uboot的输出就都显示在LCD上了，我们的输入还是选择的串口输入，输入信息也都显示在LCD屏之上效果图如下：

我把uboot的原始显示图片给替换掉了，故显示如上，图片上有些个人信息被我抹掉了。