Linux-2.6.14內核在S3C2410上的移植
2.4內核由于本身并不支持2410,移植起來較為煩瑣,所以直接上2.6的版本.
1.準備工作
下載解壓交叉編譯工具,2.6的內核編譯要用3.4.1版本的(arm-linux-gcc-3.4.1)ftp://ftp.handhelds.org/projects/toolchain/arm-linux-gcc-3.4.1.tar.bz2
下載解壓2.6.14.1內核ftp://ftp.kernel.org/pub/linux/kernel/v2.6/.
之前文章已經說明不再贅述.
2.Flash分區(qū)管理
啟動開發(fā)板,進入vivi,查看vivi的分區(qū)信息.
分區(qū)信息如下所示:
分區(qū)
起始地址
分區(qū)大小
分區(qū)作用
Part0
0x0
0x00020000 (128k)
bootloader
Part1
0x00020000
0x00010000 (64k)
bootloader params
Part2
0x00030000
0x001c0000 (1m+768k)
linux kernel
Part3
0x00200000
0x00400000 (4m)
root filesystem
Part4
0x00600000
0x03a00000 (58m)
usr filesystem
根據實際需要也可相應的更改分區(qū)表.
3.修改Makefile
#vi Makefile
找到ARCH與CROSS_COMPILE,修改為
ARCH ?= arm
CROSS_COMPILE ?= /usr/local/arm/3.4.1/bin/arm-linux-
4.將Flash分區(qū)信息加入內核
#vi arch/arm/mach-s3c2410/devs.c
添加頭文件:
#include
#include
#include
添加分區(qū)結構:
static struct mtd_partition partition_info[]={
{name:"bootloader",
offset:0,
size: 0x00020000,},
{name:"param",
offset:0x00020000,
size:0x00010000,},
{name:"kernel",
offset:0x00030000,
size:0x001c0000,},
{name:"root",
offset:0x00200000,
size:0x00400000,},
{name:"usr",
offset:0x00600000,
size:0x03a00000,}
};
struct s3c2410_nand_set nandset={
nr_partitions: 5, //分區(qū)數量
partitions: partition_info, //分區(qū)表
};
struct s3c2410_platform_nand superlpplatform={
//NAND Flash芯片支持
//參數意義可參考S3C2410手冊
tacls: 0,
twrph0: 30,
twrph1: 0,
sets: &nandset,
nr_sets: 1,
};
修改s3c_device_nand,以加入NAND Flash驅動:
struct platform_device s3c_device_nand = {
.name = "s3c2410-nand", //設備名稱
.id = -1,//有效設備編號,-1表示唯一設備
.num_resources = ARRAY_SIZE(s3c_nand_resource), //寄存器區(qū)的個數
.resource = s3c_nand_resource, //寄存器區(qū)的首地址
//添加如下信息,表示NAND Flash設備
.dev={
.platform_data=&superlpplatform
}
};
5.指定啟動時的設備初始化
#vi arch/arm/mach-s3c2410/mach-smdk2410.c
修改:
static struct platform_device *smdk2410_devices[] __initdata = {
&s3c_device_usb,
&s3c_device_lcd,
&s3c_device_wdt,
&s3c_device_i2c,
&s3c_device_iis,
//添加如下信息
&s3c_device_nand,
};
6.禁止FlashECC效驗
內核通過vivi把數據寫入NAND Flash,而vivi的ECC效驗算法和內核的不同,內核的效驗碼是由NAND Flash控制器產生的,所以在此必須禁用NAND Flash ECC。
#vi drivers/mtd/nand/s3c2410.c
找到s3c2410_nand_init_chip函數,加入chip->eccmode的值為:
NAND_ECC_NONE
7.內核配置與編譯
為了我們的內核支持devfs以及在啟動時并在/sbin/init運行之前能自動掛載/dev為devfs文件系統,修改fs/Kconfig文件
#vi fs/Kconfig
找到menu "Pseudo filesystems"
添加如下語句:
config DEVFS_FS
bool "/dev file system support (OBSOLETE)"
default y
config DEVFS_MOUNT
bool "Automatically mount at boot"
default y
depends on DEVFS_FS
配置內核:
#cp arch/arm/configs/smdk2410_defconfig .config
#make menuconfig
在smdk2410_defconfig基礎上,增刪的內核配置項如下:
Loadable module support >
[*] Enable loadable module support
[*] Automatic kernel module loading
System Type >
[*] S3C2410 DMA support
Boot options >
Default kernel command string:
noinitrd root=/dev/mtdblock3 init=/linuxrc console=ttySAC0,115200
#說明:mtdblock2代表我的第3個flash分區(qū),它是我的rootfs
# console=ttySAC0,115200使kernel啟動期間的信息全部輸出到串口0上.
# 2.6內核對于串口的命名改為ttySAC0,但這不影響用戶空間的串口編程。
# 用戶空間的串口編程針對的仍是/dev/ttyS0等
Floating point emulation >
[*] NWFPE math emulation
This is necessary to run most binaries!!!
Device Drivers >
Memory Technology Devices (MTD) >
[*] MTD partitioning support
#支持MTD分區(qū),這樣我們在前面設置的分區(qū)才有意義
[*] Command line partition table parsing
#支持從命令行設置flash分區(qū)信息,靈活
RAM/ROM/Flash chip drivers >
<*> Detect flash chips by Common Flash Interface (CFI) probe
<*> Detect nonCFI AMD/JEDECcompatible flash chips
<*> Support for Intel/Sharp flash chips
<*> Support for AMD/Fujitsu flash chips
<*> Support for ROM chips in bus mapping
NAND Flash Device Drivers >
<*> NAND Device Support
<*> NAND Flash support for S3C2410/S3C2440 SoC
Character devices >
[*] Nonstandard serial port support
[*] S3C2410 RTC Driver
File systems >
<> Second extended fs support #去除對ext2的支持
Pseudo filesystems >
[*] /proc file system support
[*] Virtual memory file system support (former shm fs)
[*] /dev file system support (OBSOLETE)
[*] Automatically mount at boot (NEW)
#這里會看到我們前先修改fs/Kconfig的成果,devfs已經被支持上了
Miscellaneous filesystems >
<*> Compressed ROM file system support (cramfs)
#支持cramfs
Network File Systems >
<*> NFS file system support
編譯內核:
#make zImage
8.加載內核
vivi>load flash kernel t
修改vivi啟動參數:
vivi>param set linux_cmd_line “noinitrd root=/dev/mtdblock/3 init=/linuxrc console=ttySAC0,115200”
vivi>param save