kernel version：2.6.33.7
/linux-2.6.33.7
OS：CentOS 6.4
cross-compilation chain：arm-linux-4.3.2
/usr/local/arm/4.3.2/bin
第一步：修改配置
（1）选择合适的内核代码，作为硬件参考目标平台
arch/arm/mach-s3c2440
内核版本支持s3c2440，所以不需要作修改。
（2）修改顶层Makefile
设置体系架构：line193:ARCH?=$(SUBARCH)改为ARCH=arm
设置编译工具：line194:CROSS_COMPILE?=改为CROSS_COMPILE=arm-linux-
（3）修改输入时钟
修改arch/arm/mach-s3c2440/mach-smdk2440.c中line163：s3c24xx_init_clocks(12000000)
第二步：给内核打支持yaffs2文件系统的补丁
（1）下载：git clone git://www.aleph1.co.uk/yaffs2
（2）解压到/root，执行./patch-ker.sh c m /linux-2.6.33.7
第三步：配置内核
（1）选择参考配置文件
选择arch/arm/configs/s3c2440_defconfig作为配置参考。复制s3c2440_defconfig到顶层目录，更名.config
（2）清除临时文件、中间文件和配置文件
make clean 移除生成文件，保留配置文件
make mrproper 移除生成文件和配置文件
make distclean 移除所有文件
（3）配置内核
make config 文本模式配置
make menuconfig 文本菜单配置
make ddconfig 使用已有.config，但询问新增的配置选项
make xconfig 图形菜单配置
*********************************************** 内核选项 ***********************************************
-------------------------------------------------------------------------------------------------------------
配置Yaffs2文件支持
修改配置如下：
File systems --->
[*] Miscellaneous filesystems --->
<*> YAFFS2 file system support
-*- 512 byte / page devices
-*- 2048 byte (or larger) / page devices
[*] Autoselect yaffs2 format
[*] Cache short names in RAM
-------------------------------------------------------------------------------------------------------------
配置cpu相关选项
修改配置如下：
System Type --->
S3C2440 Machines --->
[*] SMDK2440
[*] SMDK2440 with S3C2440 CPU module
-------------------------------------------------------------------------------------------------------------
移植USB host驱动，仅仅需要修改配置即可
Device Drivers --->
[*] USB support --->
{*} Support for Host-side USB
[*] USB device filesystem (DEPRECATED)
[*] USB device class-devices (DEPRECATED)
<*> OHCI HCD support
<*> USB Mass Storage support
[*] HID Devices --->
{*} Generic HID support
[*] /dev/hidraw raw HID device support
SCSI device support --->
<*> SCSI device support
[*] legacy /proc/scsi/ support
<*> SCSI disk support
<*> SCSI tape support
-------------------------------------------------------------------------------------------------------------
移植RTC驱动
Device Drivers --->
<*> Real Time Clock --->
[*] Set system time from RTC on startup and resume
(rtc0) RTC used to set the system time
[ ] RTC debug support
*** RTC interfaces ***
[*] /sys/class/rtc/rtcN (sysfs)
[*] /proc/driver/rtc (procfs for rtc0)
[*] /dev/rtcN (character devices)
<*> Samsung S3C series SoC RTC
添加对设备的支持：
# vi arch/arm/mach-s3c2440/mach-smdk2440.c
将smdk2440_devices增加一行&s3c_device_rtc,。
static struct platform_device *smdk2440_devices[] __initdata = {
&s3c_device_usb,
&s3c_device_lcd,
&s3c_device_wdt,
&s3c_device_i2c0,
&s3c_device_iis,
&s3c_device_rtc,//新增的一行
};
-------------------------------------------------------------------------------------------------------------
移植UDA1341驱动
# vi arch/arm/mach-s3c2440/mach-smdk2440.c
添加头文件：
#include <sound/s3c24xx_uda134x.h>
#include <mach/gpio-fns.h>
增加：
static struct s3c24xx_uda134x_platform_data s3c24xx_uda134x_data = {
.l3_clk = S3C2410_GPB(4),
.l3_data = S3C2410_GPB(3),
.l3_mode = S3C2410_GPB(2),
.model = UDA134X_UDA1341,
};
static struct platform_device s3c24xx_uda134x = {
.name = "s3c24xx_uda134x",
.dev = {
.platform_data = &s3c24xx_uda134x_data,
}
};
添加：
static struct platform_device *smdk2440_devices[] __initdata = {
&s3c_device_usb,
&s3c_device_lcd,
&s3c_device_wdt,
&s3c_device_i2c0,
&s3c_device_iis,
&s3c_device_rtc,
&s3c24xx_uda134x,//增加
};
配置内核
Device Drivers --->
<*> Sound card support --->
<*> Advanced Linux Sound Architecture --->
<*> OSS Mixer API
<*> OSS PCM (digital audio) API
[*] OSS PCM (digital audio) API - Include plugin system
[*] Support old ALSA API
[*] Verbose procfs contents
[*] Verbose printk
[*] Generic sound devices --->
<*> ALSA for SoC audio support --->
<*> SoC Audio for the Samsung S3C24XX chips
<*> SoC I2S Audio support UDA134X wired to a S3C24XX
-------------------------------------------------------------------------------------------------------------
移植DM9000驱动
修改 drivers/net/dm9000.c 文件
# vi drivers/net/dm9000.c
#include <mach/regs-gpio.h>
#include <mach/irqs.h>
#include <mach/hardware.h>
在dm9000_probe 函数开始增加：
unsigned char ne_def_eth_mac_addr[]={0x00,0x12,0x34,0x56,0x80,0x49};
static void *bwscon;
static void *gpfcon;
static void *extint0;
static void *intmsk;
#define BWSCON (0x48000000)
#define GPFCON (0x56000050)
#define EXTINT0 (0x56000088)
#define INTMSK (0x4A000008)
bwscon=ioremap_nocache(BWSCON,0x0000004);
gpfcon=ioremap_nocache(GPFCON,0x0000004);
extint0=ioremap_nocache(EXTINT0,0x0000004);
intmsk=ioremap_nocache(INTMSK,0x0000004);
writel(readl(bwscon)|0xc0000,bwscon);
writel( (readl(gpfcon) & ~(0x3 << 14)) | (0x2 << 14), gpfcon);
writel( readl(gpfcon) | (0x1 << 7), gpfcon); // Disable pull-up
writel( (readl(extint0) & ~(0xf << 28)) | (0x4 << 28), extint0); //rising edge
writel( (readl(intmsk)) & ~0x80, intmsk);
函数最后修改：
if (!is_valid_ether_addr(ndev->dev_addr)) {
/* try reading from mac */
mac_src = "chip";
for (i = 0; i < 6; i++)
//ndev->dev_addr[i] = ior(db, i+DM9000_PAR);
ndev->dev_addr[i] = ne_def_eth_mac_addr[i];//修改这里
}
修改arch/arm/mach-s3c2440/mach-smdk2440.c，添加设备
static struct platform_device *smdk2440_devices[] __initdata = {
&s3c_device_usb,
&s3c_device_lcd,
&s3c_device_wdt,
&s3c_device_i2c0,
&s3c_device_iis,
&s3c_device_rtc,
&s3c24xx_uda134x,
&s3c_device_dm9000,//添加
};
修改文件arch/arm/plat-s3c24xx/devs.c
# vi arch/arm/plat-s3c24xx/devs.c
添加：
#include <linux/dm9000.h>
static struct resource s3c_dm9000_resource[] = {
[0] = {
.start = S3C24XX_PA_DM9000,
.end = S3C24XX_PA_DM9000+ 0x3,
.flags = IORESOURCE_MEM
},
[1]={
.start = S3C24XX_PA_DM9000 + 0x4, //CMD pin is A2
.end = S3C24XX_PA_DM9000 + 0x4 + 0x7c,
.flags = IORESOURCE_MEM
},
[2] = {
.start = IRQ_EINT7,
.end = IRQ_EINT7,
.flags = IORESOURCE_IRQ
},
};
static struct dm9000_plat_data s3c_device_dm9000_platdata = {
.flags= DM9000_PLATF_16BITONLY,
};
struct platform_device s3c_device_dm9000 = {
.name= "dm9000",
.id= 0,
.num_resources= ARRAY_SIZE(s3c_dm9000_resource),
.resource= s3c_dm9000_resource,
.dev= {
.platform_data = &s3c_device_dm9000_platdata,
}
};
EXPORT_SYMBOL(s3c_device_dm9000);
修改arch/arm/plat-s3c/include/plat/devs.h
# vi arch/arm/plat-s3c/include/plat/devs.h
添加：
extern struct platform_device s3c_device_dm9000;
修改arch/arm/mach-s3c2410/include/mach/map.h
# vi arch/arm/mach-s3c2410/include/mach/map.h
新增
/* DM9000 */
#define S3C24XX_PA_DM9000 0x20000300
#define S3C24XX_VA_DM9000 0xE0000000
如果无法发现网卡，修改arch/arm/mach-s3c2410/mach-smdk2410.c在smdk2410_devices
增加以下行
&s3c_device_dm9000,
另外在static struct map_desc smdk2410_iodesc[] __initdata增加以下内容
[0] = {
.virtual = (unsigned long)S3C24XX_VA_DM9000,
.pfn = __phys_to_pfn(S3C24XX_PA_DM9000),
.length = SZ_1M,
.type = MT_DEVICE,
},
-------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------------------
*************************************************************************************************************
第四步：修改硬件配置
（1）修改机器码
机器码的作用是让bootloader（比如u-boot）识别内核的。此机器码必须与bootloader中的机器码一致，否则不能启动。
飞凌开发板的bootloader 默认的机器码是193，所以我们在使用FL2440 机器的时候，需要修改机器码。
修改arch/arm/tools/mach-types。将
s3c2440 ARCH_S3C2440 S3C2440 362
修改为193。
删除
s3c2410...一项
（2）修改MTD分区
修改MTD分区（linux已有Nand Flash驱动，只需要对MTD分区进行修改，要与bootloader中对nand flash分区一致）
文件： arch/arm/plat-s3c24xx/common-smdk.c
结构体：static struct mtd_partition smdk_default_nand_part[]
static struct mtd_partition smdk_default_nand_part[] = {
[0] = {
.name = "Boot",
.size = 0x00100000,
.offset = 0
},
[1] = {
.name = "MyApp",
.size = 0x003c0000,
.offset = 0x00140000,
},
[2] = {
.name = "Kernel",
.size = 0x00300000,
.offset = 0x00500000,
},
[3] = {
.name = "fs_yaffs",
.size = 0x03c00000, //30M
.offset = 0x00800000,
},
// [4] = {
// .name = "WINCE",
// .size = 0x03c00000,
// .offset = 0x04400000,
// }
};
（3）移植Nand Flash驱动
关闭ECC校验：
文件：drivers/mtd/nand/s3c2410.c
函数：s3c2410_nand_init_chip
/*chip->ecc.mode = NAND_ECC_SOFT; */ chip->ecc.mode = NAND_ECC_NONE;
修改Nand Flash驱动
文件：drivers/mtd/nand/nand_bbt.c
static struct nand_bbt_descr largepage_memorybased = {
.options = 0,
.offs = 0,
.len = 1, // 原数值为2，支持2K 每页的flash 修改为1。K9F1G08，K9F2G08是2k 每页的flash
.pattern = scan_ff_pattern
};
static struct nand_bbt_descr largepage_flashbased = {
.options = NAND_BBT_SCAN2NDPAGE,
.offs = 0,
.len = 1, //原数值为2，支持2K 每页的flash 修改为1。K9F1G08，K9F2G08是2k 每页的flash
.pattern = scan_ff_pattern
};
第五步：编译内核
顶层目录编译，生成zImage
make zImage
在文件夹arch/arm/boot中