移植内核2.6.24.4到S3C2440

百经周折，终于新内核启动了新的系统。

多谢小卒的指导，还有这两篇文章的作者，给了我很多帮助。

[url]http://blog.chinaunix.net/u2/63560/showart_511924.html[/url]

[url]http://blog.csdn.net/hongjiujing/archive/2007/09/19/1790842.aspx[/url]

很多工作还刚开始，先记录下来，别以后自己都忘了。

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移植环境：

主机：CentOS 5.1

交叉编译器：arm-linux-gcc-3.4.1

开发板平台：S3C2440（YL-2440/YLP-2440开发板）

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准备工作：

下载Linux内核源代码： [url]http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.24.4.tar.bz2[/url] (上去一看，今天2.6.25的内核出来了)

交叉编译工具包：从光盘一般都带，没有到网上找找也有。

解压源码：tar -jxvf linux-2.6.24.4.tar.bz2

安装交叉编译工具：tar -jxvf arm-linux-gcc-3.4.1.tar.bz2 -C /

会将工具安装在/usr/local/arm/3.4.1/中，视各人的环境可能不同，自己修改Makefile中的路径即可。

 

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修改配置文件：

1．修改Makefile，匹配交叉编译器。

在内核代码根目录下：vim Makefile

在193行找到ARCH

修改为

ARCH = arm

CROSS_COMPILE ?= /usr/local/arm/3.4.1/bin/arm-linux-

CORSS_COMPILE视自己的环境定

 

2． 为了内核支持devfs 以及在启动时并在/sbin/init 运行之前能自动挂载/dev为devfs 文件系统。编辑fs/Kconfig：

在906 行menu "Pseudo filesystems"下面添加如下代码：

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

 

3．

 

 

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修改源代码：

1. 修改对nand的分区信息。要让内核知道nand flash的分区信息，设置成跟bootloader一致。

在arch/arm/plat-s3c24xx/common-smdk.c中修改smdk_default_nand_part[]，注意这个一定要跟bootloader的一致。在我的板子中修改如下：

static struct mtd_partition smdk_default_nand_part[] = {

        [0]={

                .name = "boot",

                .size = SZ_128K + SZ_64K,   //192k 0x00300000

                .offset = 0,

                },

        [1]={

                .name = "kernel",

                .size = SZ_16K * 116,            //2M - 192K    0x01e00000

                .offset = SZ_16K *12,           //192K

                },

        [2]={

                .name = "rootfs",

                .offset = SZ_2M,                 

                .size = SZ_2M * 15,                     //30M

                },

        [3]={

                .name = "User",

                .offset = SZ_32M,

                .size = SZ_32M,

                }

};

 

另外这个文件还要修改smdk_nand_info如下：

static struct s3c2410_platform_nand smdk_nand_info = {

.tacls               = 0,        //default is 20

.twrph0           = 30,       //default is 60

.twrph1           = 0,        //defualt is 20 changed by yangdk

.nr_sets    = ARRAY_SIZE(smdk_nand_sets),

.sets         = smdk_nand_sets,

};

 

 

2． 修改时钟

       在arch/arm/mach-s3c2440/mach-smdk2440.c中修改smdk2440_map_io如下

    static void __init smdk2440_map_io(void)

{

s3c24xx_init_io(smdk2440_iodesc, ARRAY_SIZE(smdk2440_iodesc));

s3c24xx_init_clocks( 12000000);      //default is 16934400, changed by yangdk

s3c24xx_init_uarts(smdk2440_uartcfgs, ARRAY_SIZE(smdk2440_uartcfgs));

}

 

3．修改nand Flash的校验方式，去掉ECC校验。

       在drivers/mtd/nand/s3c2410.c 第669行

       将chip->ecc.mode = NAND_ECC_SOFT;

       改为 chip->ecc.mode = NAND_ECC_NONE;

       注意：这个去掉ECC校验的问题，在内核中明确说明是不建议这样做的，因为这样就等于忽略了对NAND FLASH坏块的检测。而我一开始也是编译的时候就去掉了ECC校验的选项，原以为在编译选项中去掉就可以了，结果一直报这样的错：

end_request: I/O error, dev mtdblock2, sector 0

FAT: unable to read boot sector

VFS: Cannot open root device "mtdblock2" or unknown-block(31,2)

Please append a correct "root=" boot option; here are the available partitions:

1f00         192 mtdblock0 (driver?)

1f01        1856 mtdblock1 (driver?)

1f02       30720 mtdblock2 (driver?)

1f03       32768 mtdblock3 (driver?)

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,2)

       郁闷了一个整天。后来发现配置中去掉的这个选项在代码中并没有完全去掉，只是去掉了硬件校验的方式，换成了软件校验。只有在代码中给改成NAND_ECC_NONE，才不会校验，但是这样是不提倡的。可是这有这样最后我的系统才起来，阿弥陀佛！

 

 

配置及编译内核

先把默认配置文件拷贝过来

cp arch/arm/configs/s 3c 2410_defconfig .config

配置

Make menuconfig

 

[*] Enable loadable module support --->

       [*]   Module unloading

       [*]   Automatic kernel module loading

       选择这两个，剩下的可以去掉

 

System Type ---->

       [*] S3C2410 DMA support

       [*] Support ARM920T processor

       S3C2410 Machines --->

              [*] SMDK2410/A9M2410 

       S3C2440 Machines --->

              [*] SMDK2440

              [*] SMDK2440 with S3C2440 CPU module

 

System Type这部分，只选这些，其他可以全部去掉，我的这个还选上了队Thumb的支持。另外，网上一些帖子都说只选上SMDK2440就可以了，其他的都去掉，事实上是不行的，我试了多次，都在编译时

到arch/arm/plat-s3c24xx/s3c24xx.o时，报错：

arch/arm/plat-s3c24xx/s3c244x.c: In function `s3c244x_init_clocks':

arch/arm/plat-s3c24xx/s3c244x.c:121: error: implicit declaration of function `s3c2410_baseclk_add'

make[1]: *** [arch/arm/plat-s3c24xx/s3c244x.o] 错误 1

make: *** [arch/arm/plat-s3c24xx] 错误 2

我再选上SMDK2410/A9M2410，问题解决。

 

Boot option ----->

       修改启动参数为：

       noinitrd root=/dev/mtdblock2 init=/linuxrc console=ttySAC0,115200

       可能根据个人板子的设置会不一样，我的是从Nand Flash中加载文件系统，其中mtdblock2是存放我的Linux文件系统的分区。不过，在bootloader可以传递内核参数的情况下这个设置是无效的。

 

Device Drivers --->

       <*> Memory Technology Device (MTD) support --->

              [*]   MTD partitioning support

              <*> NAND Device Support --->

                      <*>   NAND Flash support for S3C2410/S3C2440 SoC

                      [ ]    S3C2410 NAND Hardware ECC     // 这个要去掉

       [*] Network device support --->

               [*]   Ethernet (10 or 100Mbit) ---> 

                   <*>   DM9000 support

       < > Real Time Clock --->   // 这个去掉

 

       去掉红字的两个部分，黑子部分选上，其他的选择默认就可以了。

 

File systems --->

       <*> ROM file system support

       因为我的文件系统用cramfs，选择这个，其他用默认。

 

 

到此为止，基本完成。下面正式编译

make zImage

……

上个厕所，洗把脸，吃个苹果，20分钟后陆续出现这个

 SYSMAP System.map

 SYSMAP .tmp_System.map

 OBJCOPY arch/arm/boot/Image

 Kernel: arch/arm/boot/Image is ready

 AS       arch/arm/boot/compressed/head.o

 GZIP     arch/arm/boot/compressed/piggy.gz

 AS       arch/arm/boot/compressed/piggy.o

 CC       arch/arm/boot/compressed/misc.o

 LD       arch/arm/boot/compressed/vmlinux

 OBJCOPY arch/arm/boot/zImage

 Kernel: arch/arm/boot/zImage is ready

小高兴一下，编译成功！

 

 

烧写新内核

……

启动新内核：

Read chip id = ec76

Nand flash status = c0

Set boot params = root=/dev/mtdblock2 init=/linuxrc load_ramdisk=0 console=ttySAC1,115200 mem=65536K devfs=mount

Load Kernel...

Linux version 2.6.24.4 (root@centos) (gcc version 3.4.1) #13 Thu Apr 17 10:45:28 CST 2008

CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c0007177

Machine: SMDK2410

ATAG_INITRD is deprecated; please update your bootloader.

Memory policy: ECC disabled, Data cache writeback

CPU S3C2440A (id 0x32440001)

S3C244X: core 400.000 MHz, memory 100.000 MHz, peripheral 50.000 MHz

S3C24XX Clocks, (c) 2004 Simtec Electronics

CLOCK: Slow mode (1.500 MHz), fast, MPLL on, UPLL on

CPU0: D VIVT write-back cache

CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets

CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets

Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256

Kernel command line: root=/dev/mtdblock2 init=/linuxrc load_ramdisk=0 console=ttySAC1,115200 mem=65536K devfs=mount

irq: clearing pending ext status 0000d400

irq: clearing subpending status 00000092

PID hash table entries: 256 (order: 8, 1024 bytes)

timer tcon=00590000, tcnt a2c1, tcfg 00000200,00000000, usec 00001eb8

Console: colour dummy device 80x30

console [ttySAC1] enabled

Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)

Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)

Memory: 64MB = 64MB total

Memory: 61568KB available (2896K code, 299K data, 124K init)

Mount-cache hash table entries: 512

CPU: Testing write buffer coherency: ok

net_namespace: 64 bytes

NET: Registered protocol family 16

S3C2410 Power Management, (c) 2004 Simtec Electronics

S3C2440: Initialising architecture

S3C2440: IRQ Support

S3C2440: Clock Support, DVS off

S3C24XX DMA Driver, (c) 2003-2004,2006 Simtec Electronics

DMA channel 0 at c4800000, irq 33

DMA channel 1 at c4800040, irq 34

DMA channel 2 at c4800080, irq 35

DMA channel 3 at c48000c0, irq 36

usbcore: registered new interface driver usbfs

usbcore: registered new interface driver hub

usbcore: registered new device driver usb

NET: Registered protocol family 2

IP route cache hash table entries: 1024 (order: 0, 4096 bytes)

TCP established hash table entries: 2048 (order: 2, 16384 bytes)

TCP bind hash table entries: 2048 (order: 1, 8192 bytes)

TCP: Hash tables configured (established 2048 bind 2048)

TCP reno registered

NetWinder Floating Point Emulator V0.97 (double precision)

JFFS2 version 2.2. (NAND) 漏 2001-2006 Red Hat, Inc.

fuse init (API version 7.9)

io scheduler noop registered

io scheduler anticipatory registered (default)

io scheduler deadline registered

io scheduler cfq registered

s3c2410-lcd s3c2410-lcd: no platform data for lcd, cannot attach

s3c2410-lcd: probe of s3c2410-lcd failed with error -22

lp: driver loaded but no devices found

ppdev: user-space parallel port driver

Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled

s3c2440-uart.0: s3c2410_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2440

s3c2440-uart.1: s3c2410_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2440

s3c2440-uart.2: s3c2410_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2440

RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize

loop: module loaded

dm9000 Ethernet Driver

Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2

ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx

S3C24XX NAND Driver, (c) 2004 Simtec Electronics

s3c2440-nand s3c2440-nand: Tacls=1, 10ns Twrph0=7 70ns, Twrph1=1 10ns

NAND device: Manufacturer ID: 0xec, Chip ID: 0x76 (Samsung NAND 64MiB 3,3V 8-bit)

NAND_ECC_NONE selected by board driver. This is not recommended !!

Scanning device for bad blocks

Creating 4 MTD partitions on "NAND 64MiB 3,3V 8-bit":

0x00000000-0x00030000 : "bootloader"

0x00030000-0x00200000 : "kernel_zImage"

0x00200000-0x02000000 : "rootfs"

0x02000000-0x04000000 : "User"

usbmon: debugfs is not available

s3c2410-ohci s3c2410-ohci: S3C24XX OHCI

s3c2410-ohci s3c2410-ohci: new USB bus registered, assigned bus number 1

s3c2410-ohci s3c2410-ohci: irq 42, io mem 0x49000000

usb usb1: configuration #1 chosen from 1 choice

hub 1-0:1.0: USB hub found

hub 1-0:1.0: 2 ports detected

mice: PS/2 mouse device common for all mice

s3c2440-i2c s3c2440-i2c: slave address 0x10

s3c2440-i2c s3c2440-i2c: bus frequency set to 390 KHz

s3c2440-i2c s3c2440-i2c: i2c-0: S3C I2C adapter

S3C2410 Watchdog Timer, (c) 2004 Simtec Electronics

s3c2410-wdt s3c2410-wdt: watchdog inactive, reset disabled, irq enabled

TCP cubic registered

NET: Registered protocol family 1

RPC: Registered udp transport module.

RPC: Registered tcp transport module.

VFS: Mounted root (cramfs filesystem) readonly.

Freeing init memory: 124K

init started: BusyBox v1.9.2 (2008-04-16 00:31:28 CST)

starting pid 772, tty '': '/etc/init.d/rcS'

#mount all.......

# starting mdev....

******************************************

        yangdk linux-2.6.24.4 boot

 

******************************************

starting pid 778, tty '': '/bin/sh'

 

Processing /etc/profile......Done!

/ #

说明内核已经正常工作了。。。

 

从红色部分知道，已经加载文件系统成功了!文件系统是在busybox1.9.2的基础上建立的。主要是参考了 [url]http://blog.chinaunix.net/u2/63560/showart_518011.html[/url] ，谢谢作者！

另外一个注意的是使用mkcramfs工具的时候要使用-e选项指定版本号为2.6.24.4，来和新的内核匹配，否则的话就会像我之前和郁闷的出现这样的错误。

Warning: unable to open an initial console.

clk: version magic '2.6.12-h1940 ARMv4 gcc-3.4' should be '2.6.24.4 mod_unload ARMv4 '

s3c2410mci: version magic '2.6.12-h1940 ARMv4 gcc-3.4' should be '2.6.24.4 mod_unload ARMv4 '

为这个还要费尽周折找到mkcramfs的源代码才知道有-e这么一个选项，其实可以通过mkcramfs �Chelp来查看的，却没想到，真晕~~~