2018年10月11日 | OK6410之LCD驱动

lcd.c驱动源码：

#include "linux/module.h"  

#include "linux/kernel.h"  

#include "linux/errno.h"  

#include "linux/string.h"  

#include "linux/mm.h"  

#include "linux/slab.h"  

#include "linux/vmalloc.h"  

#include "linux/delay.h"  

#include "linux/interrupt.h"  

#include "asm/uaccess.h"  

#include "linux/fb.h"  

#include "linux/init.h"  

#include "linux/clk.h"  

#include "linux/dma-mapping.h"  

static struct fb_info *s3c_lcd_info;  

static u32 s3c_pseudo_palette[16];  

static volatile unsigned long *gpbcon;  

static volatile unsigned long *gpbdat;  

static volatile unsigned long *gpfcon;  

static volatile unsigned long *gpfdat;  

static volatile unsigned long *gpicon;  

static volatile unsigned long *gpjcon;  

static volatile unsigned long *mifpcon;  

static volatile unsigned long *spcon;  

struct s3c6410_lcd_regs {  

    unsigned long vidcon0;  

    unsigned long vidcon1;  

    unsigned long vidcon2;  

    unsigned long reserver1;  

    unsigned long vidtcon0;  

    unsigned long vidtcon1;  

    unsigned long vidtcon2;  

    unsigned long reserver2;  

    unsigned long wincon0;  

    unsigned long wincon1;  

    unsigned long wincon2;  

    unsigned long wincon3;  

    unsigned long wincon4;  

    unsigned long reserver3[3];  

    unsigned long vidosd0a;  

    unsigned long vidosd0b;  

    unsigned long vidosd0c;  

    unsigned long reserver4;  

    unsigned long vidosd1a;  

    unsigned long vidosd1b;  

    unsigned long vidosd1c;  

    unsigned long vidosd1d;  

    unsigned long vidosd2a;  

    unsigned long vidosd2b;  

    unsigned long vidosd2c;  

    unsigned long vidosd2d;  

    unsigned long vidosd3a;  

    unsigned long vidosd3b;  

    unsigned long vidosd3c;  

    unsigned long reserver5;  

    unsigned long vidosd4a;  

    unsigned long vidosd4b;  

    unsigned long vidosd4c;  

    unsigned long reserver6[5];  

    unsigned long vidw00add0b0;  

    unsigned long vidw00add0b1;  

    unsigned long vidw01add0b0;  

    unsigned long vidw01add0b1;  

    unsigned long vidw02add0;  

    unsigned long reserver7;  

    unsigned long vidw03add0;  

    unsigned long reserver8;  

    unsigned long vidw04add0;  

    unsigned long reserver9[3];  

    unsigned long vidw00add1b0;  

    unsigned long vidw00add1b1;  

};  

static inline unsigned int chan_to_field(unsigned int chan, struct fb_bitfield *bf)  

{  

    chan &= 0xffff;  

    chan >>= 16 - bf->length;  

    return chan << bf->offset;  

}  

static int s3c_fb_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;  

    u32 *pal = info->pseudo_palette;  

    // 用red,green,blue三原色构造出val   

    val  = chan_to_field(red,   &info->var.red);  

    val |= chan_to_field(green, &info->var.green);  

    val |= chan_to_field(blue,  &info->var.blue);  

    pal[regno] = val;  

    return 0;  

}  

static struct fb_ops s3c_fb_ops = {  

    .owner = THIS_MODULE,  

    .fb_setcolreg   = s3c_fb_setcolreg,  

    .fb_fillrect    = cfb_fillrect,  

    .fb_copyarea    = cfb_copyarea,  

    .fb_imageblit   = cfb_imageblit,  

};  

static struct s3c6410_lcd_regs * lcd_regs;  

static int s3c_lcd_init(void)  

{  

    struct clk *clk;  

    int hclk;  

    int clkval;  

    // 1. 分配fb_info   

    s3c_lcd_info = framebuffer_alloc(0, NULL);  

    // 2. 设置   

    // 2.1 设置固定的信息   

    strcpy(s3c_lcd_info->fix.id, "uplooking_lcd");  

    s3c_lcd_info->fix.smem_len    = 480*272*2;  

    s3c_lcd_info->fix.type        = FB_TYPE_PACKED_PIXELS;  

    s3c_lcd_info->fix.visual      = FB_VISUAL_TRUECOLOR;  

    s3c_lcd_info->fix.line_length = 480*2;  

    // 2.2 设置可变的信息   

    s3c_lcd_info->var.xres           = 480;  //分辨率

    s3c_lcd_info->var.yres           = 272;  

    s3c_lcd_info->var.xres_virtual   = 480;  //虚拟分辨率

    s3c_lcd_info->var.yres_virtual   = 272;  

    s3c_lcd_info->var.bits_per_pixel = 16;  

    s3c_lcd_info->var.red.length     = 5;  

    s3c_lcd_info->var.red.offset      = 11;  

    s3c_lcd_info->var.green.length    = 6;  

    s3c_lcd_info->var.green.offset     = 5;  

    s3c_lcd_info->var.blue.length     = 5;  

    s3c_lcd_info->var.blue.offset       = 0;  

    s3c_lcd_info->var.activate            = FB_ACTIVATE_NOW;  

    // 2.3 设置操作函数   

    s3c_lcd_info->fbops = &s3c_fb_ops;  

    // 2.4 设置其他信息   

    //s3c_lcd_info->screen_base = ;              // 显存的虚拟地址   

    s3c_lcd_info->screen_size = 480*272*2;  

    s3c_lcd_info->pseudo_palette = &s3c_pseudo_palette;  

    // 4. 硬件相关的操作   

    // 4.1 配置GPIO用于LCD   

    gpicon = ioremap(0x7F008100, 4);  

    *gpicon = 0xAAAAAAAA;  

    gpjcon = ioremap(0x7F008120, 4);  

    *gpjcon = 0xAAAAAAAA;  

    gpbcon = ioremap(0x7F008020, 4);  

    gpbdat = gpbcon + 1;  

    gpfcon = ioremap(0x7F0080A0, 4);  

    gpfdat = gpfcon + 1;  

    // 4.2 根据LCD的性能设置LCD控制器  

    // MIFPCON   

    mifpcon = ioremap(0x7410800C, 4);  

    *mifpcon &= ~(1<<3);  

    spcon = ioremap(0x7F0081A0, 4);  

    *spcon &= ~(3);  

    *spcon |= 1;  

    lcd_regs = ioremap(0x77100000, sizeof(struct s3c6410_lcd_regs));  

    clk = clk_get(NULL, "lcd");  

    clk_enable(clk);  // HCLK_GATE[3]设为1   

    // HCLK_GATE = ioremap(0x7E00F030, 4); 

    // *HCLK_GATE |= (1<<3); 

    // bit[13:6], CLKVAL_F,VCLK = Video Clock Source / (CLKVAL+1) 

    //                                 VCLK = 9000000 

    //                 CLKVAL_F = hclk/9000000 - 1 

    // bit[3:2], CLKSEL_F, 00 = HCLK 

    // bit[1], ENVID-使能LCD控制器的输出, 先设为0, 最后全部设置好了再设为1 

    clk = clk_get(NULL, "hclk");  

    hclk = clk_get_rate(clk);  

    clkval = hclk/9000000 - 1;  

    printk(KERN_INFO "hclk = %d, clkval = %d\n", hclk, clkval);  

    lcd_regs->vidcon0 = (0<<29)|(0<<26) | (0<<17) | (clkval << 6) | (1<<4);  

    // bit[7], 0-在VLCK下降沿读数据 

    // bit[6], HSYNC低脉冲有效    

    // bit[5], VSYNC低脉冲有效    

    // bit[4], VDEN高电平有效 

    lcd_regs->vidcon1 = (0<<7) | (1<<6) | (1<<5) | (0<<4);  

    // LCD手册P11 

    // tvp = 10, tvb = 2, tvf=2 

    lcd_regs->vidtcon0 = (2<<16) | (2<<8) | (10<<0);  //修改了 都加1  

    // LCD手册P11 

    // thp = 41, thb = 2, thf=2 

    lcd_regs->vidtcon1 = (1<<16) | (1<<8) | (40<<0);  

    lcd_regs->vidtcon2 = (271<<11) | (479<<0);  

    // 4.3 分配显存, 并告诉LCD控制器   

    s3c_lcd_info->screen_base = dma_alloc_writecombine(NULL, s3c_lcd_info->screen_size,

                                                                                               &s3c_lcd_info->fix.smem_start, GFP_KERNEL);  

    // bit[17],BSWP = 0, bit[16],HWSWP = 0  

    // bit[5:2],BPPMODE_F, 0b1011, 24bpp 

    // bit[0], ENWIN_F, 0-先不使能 

    lcd_regs->wincon0 &= ~(0xf << 2);  

    //lcd_regs->wincon0 |= (0xb<<2);    // unpacked 24 BPP (non-palletized R:8-G:8-B:8 )   

    lcd_regs->wincon0 |= (0x5<<2);    

#define LeftTopX     0  

#define LeftTopY     0  

#define RightBotX   479  

#define RightBotY   271  

    lcd_regs->vidosd0a = (LeftTopX<<11) | (LeftTopY << 0);  

    lcd_regs->vidosd0b = (RightBotX<<11) | (RightBotY << 0);  

    //lcd_regs->vidosd0c = 480*272/2;  

    lcd_regs->vidosd0c = 480*272;  

    lcd_regs->vidw00add0b0 = s3c_lcd_info->fix.smem_start;  

    lcd_regs->vidw00add1b0 = (s3c_lcd_info->fix.smem_start + s3c_lcd_info->fix.smem_len) & 0xffffff;         

    // 4.4 使能   

    lcd_regs->vidcon0 |= (3);        // 使能LCD控制器输出信号   

    lcd_regs->wincon0 |= (1<<0); // 使能窗口0   

    // 3. 注册   

    register_framebuffer(s3c_lcd_info);  

    return 0;  

}  

static void s3c_lcd_exit(void)  

{  

    struct clk *clk;  

    unregister_framebuffer(s3c_lcd_info);  

    lcd_regs->vidcon0 &= ~(1<<1); // 禁止LCD控制器输出信号   

    lcd_regs->wincon0 &= ~(1<<0); // 禁止窗口0   

    dma_free_writecombine(NULL, s3c_lcd_info->screen_size, s3c_lcd_info->screen_base, 

                                             s3c_lcd_info->fix.smem_start);  

    clk = clk_get(NULL, "lcd");  

    clk_disable(clk);  // HCLK_GATE[3]设为0   

    iounmap(lcd_regs);  

    iounmap(gpbcon);  

    iounmap(gpfcon);  

    iounmap(gpicon);  

    iounmap(gpjcon);  

    iounmap(mifpcon);  

    iounmap(spcon);  

    framebuffer_release(s3c_lcd_info);  

}  

module_init(s3c_lcd_init);  

module_exit(s3c_lcd_exit);  

MODULE_LICENSE("GPL");

====================================================================

Makefile文件：

KERN_DIR = /home/linux/linux-3.0.1

all:

  make -C $(KERN_DIR) M=`pwd` modules 

clean:

  make -C $(KERN_DIR) M=`pwd` modules clean

  rm -rf modules.order

obj-m += lcd.o

==================================================================

LCD实验：

想在6410的驱动上面的测试自己的驱动首先要卸载开发板的官方驱动：

1、make menuconfig去掉内核自带的LCD驱动

在Device Drivers=>Graphics support=>S3C Framebuffer Support 

和 

   Device Drivers=>Multimedia support=>Video For Linux

这两项要去掉！

默认：

->Device Drivers

    [*] Multimedia support  ---> 

         [*]   Video For Linux

    ->Graphics support

         [*] S3C Framebuffer Support (eXtended)

               Select LCD Type (4.3 inch 480x272 TFT LCD)  --->

                   (X) 4.3 inch 480x272 TFT LCD

         [*]   Advanced options for S3C Framebuffer

                 Select BPP(Bits Per Pixel) (16 BPP)  --->

                   (X) 16 BPP

         (4)     Number of Framebuffers 

         [*]     Enable Virtual Screen

         [*]     Enable Double Buffering 

改为：

->Device Drivers

    [*] Multimedia support  ---> 

         [ ]   Video For Linux

    ->Graphics support

         [ ] S3C Framebuffer Support (eXtended)

    [*] Support for frame buffer devices  --->   //为了编译出要用的模块

         [M]  Samsung S3C Framebuffer Support

2、上面是去除自带的驱动支持，还要在arch\arm\mach-s3c64xx\mach-smdk6410.c和

change\mach-smdk6410.c这两个文件中相应的结构体注释掉：

s3c_device_vpp

s3c_device_mfc

s3c_device_tvenc

s3c_device_tvscaler

s3c_device_rotator

s3c_device_jpeg

s3c_device_g2d

s3c_device_g3d

这样子 就可以通过编译了：

make zImage                 //生成内核镜像文件

make modules

cp arch/arm/boot/zImage ../../zImage_no_lcd

然后把/drivers/video中的cfbcopyarea.ko 、cfbfillrect.ko 、cfbimgblt.ko 加载到开发板：

cp drivers/video/cfbcopyarea.ko drivers/video/cfbfillrect.ko drivers/video/cfbimgblt.ko ../../../fs_ok6410_yaffs2/driver/

3、把开发板设置为SD卡启动，使用SD卡启动后按空格进入SD卡的u-boot；

4、用SD卡里面的u-boot烧写内核到0x000000200000-0x000000700000 : "Kernel"分区：

tftp 50008000 zImage_no_lcd

nand erase 200000 500000

nand write 50008000 200000 500000

5、烧写完成后设置开发版为nand flash启动，使用新内核启动。

6、测试1：

重启开发板，然后执行以下命令

    insmod cfbcopyarea.ko 

    insmod cfbfillrect.ko 

    insmod cfbimgblt.ko 

    insmod lcd.ko

    echo hello > /dev/tty1

    可以看到屏幕打印了文字hello

    cat lcd.ko > /dev/fb0 

    可以看到花屏了

测试2：

    在开发板的文件系统的/etc/inittab文件中添加一行tty1::askfirst:-/bin/sh

    重启开发板，然后执行以下命令

        insmod cfbcopyarea.ko 

        insmod cfbfillrect.ko 

        insmod cfbimgblt.ko 

        insmod lcd.ko

    可以看到有文字在屏幕上显示，再装载我们之前做的输入子系统的按键驱动

        insmod button_input.ko

    就可以在开发板屏幕上看到shell命令行了