linux_内核移植方法及错误.doc

出现问题:
## Starting application at 0x30008000 ...
Uncompressing Linux.............................................................
解决方案:
setenv bootargs console=ttySAC0,115200 mem=64M ;console明令在哪暂时还没解决???
setenv

TCP cubic registered
NET: Registered protocol family 1
NET: Registered protocol family 17
Root-NFS: No NFS server available, giving up.
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "" or unknown-block(2,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)

解决方法：把

08.05.11、<*> RAM disk support

09.27.07、<*> Compressed ROM file system support (cramfs)

1. 问题一

　　下载内核到flash中，运行到如下即停止没有下文：

Uncompressing Linux……………………done,booting the kernel

卡在这里不动了

原因分析：可能是内核的启动参数传递时没有填写正确,
也可能是在linux内核中没对flash分区,
还有另一可能原因是在内核编译配置时没将串口驱动勾选。

解决办法：
如果是命令参数问题，则作如下修改：注释掉arch/arm/kernel/setup.c文件中的parse_tag_cmdline()函数中的strlcpy()函数，这样就可以使用默认的CONFIG_CMDLINE了，在.config文件中它被定义为"root=/dev/mtdblock2 ro init=/linuxrc console=ttySAC0,115200"(视具体情况而定)，在内核配置文件的Boot options中填入也可。

如果是内核NAND flash分区的问题，则作如下修改：

1. 1 修改文件arch/arm/mach-s3c2410/devs.c,添加如下信息：

#include

#include

#include

static struct mtd_partition partition_info[]=

{

{

name:"bootloader",

size:0x00040000,

offset:0,

},

{

name:"kernel",

size:0x001c0000,

offset:0x00040000,

},

{

name:"rootfs",

size: 0x01e00000,

offset:0x00200000,

},

{

name:"ext-fs1",

size: 0x01000000,

offset:0x02000000,

},

{

name:"ext-fs2",

size: 0x01000000,

offset:0x03000000,

},

};

//以上分区和NAND flash物理分区一样，分区不一样没试过，根据自己板子情况而定

struct s3c2410_nand_set nandset=

{

nr_partitions:5,

partitions:partition_info,

};

struct s3c2410_platform_nand s3c_nand_info=

{

tacls:0,

twrph0:30,

twrph1:0,

sets:&nandset,

nr_sets:1,

};

以上分区和NAND flash物理分区一样，分区不一样没试过，根据自己板子情况而定

struct s3c2410_nand_set nandset=

{

nr_partitions5,

partitions:partition_info,

};

struct s3c2410_platform_nand s3c_nand_info=

{

tacls:0,

twrph0:30,

twrph1:0,

sets:&nandset,

nr_sets:1,

};

struct platform_device s3c_device_nand={

.name="s3c2410-nand",

.id = -1,

.num_resources = ARRAY_SIZE(s3c_nand_resources),

.resource = s3c_nand_resource, /*黑体为新加内容*/

.dev = {

.platform_data=&s3c_nand_info

}

};

1.2 在arch/arm/mach-s3c2410/mach-smdk2410.c文件中添加&s3c_device_nand,如下所示：

static struct platform_device * smdk2410_device[] _initdata=

{

&s3c_device_usb,

&s3c_device_lcd,

&s3c_device_wdt,

&s3c_device_i2c,

&s3c_device_iis,

&s3c_device_nand,

};

配置好以上内容后重新编译内核即可。

如果是串口驱动没有勾选,则一定记住将勾上如下选项:

Character devices

-> Serial Drivers下的项勾上.

2. 出现如下错误：VFS:Cannot open root device "mtdblock/2" or unknown-block(0,0)

Please append a correct "root=" boot option.

Kernel panic not syncing,VFS Unable to mount root fs on unknown-block(0,0)

原因分析：出现这种情况一般有两种情况：没有文件系统或boot options参数不正确，如我的系统文件系统为cramfs格式，存放文件系统的分区为第三个分区，启动参数为：

"noinitrd root=/dev/mtdblock2 ro init=/linuxrc console=ttySAC0,115200 rootfstype=cramfs mem=64M"

其中文件系统使用busybox-1.10.1制作

重新编译即可。

3. 系统启动后出现如下错误：

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

或者类似的错误。

原因分析：我在这里耗了大量的时间，这种情况一般是NAND flash分区未能分正确，或者所在的分区上没有文件系统，当启动中出现类似如下信息时表明分区正确了

Scanning device for bad blocks

Creating 5 MTD partitions on "NAND 64MiB 3,3V 8-bit":

0x00000000-0x00040000 : "boot"

mtd: Giving out device 0 to boot

0x00040000-0x00200000 : "kernel"

mtd: Giving out device 1 to kernel

0x00200000-0x02000000 : "rootfs"

mtd: Giving out device 2 to rootfs

0x02000000-0x03000000 : "ext-fs1"

mtd: Giving out device 3 to ext-fs1

0x03000000-0x04000000 : "ext-fs2"

mtd: Giving out device 4 to ext-fs2

从上面看出我的文件系统放在第三个分区rootfs上，其设备号为2,启动后文件系统能挂上,如下所示

Reading data from NAND FLASH without ECC is not recommended

the error code is:0,name=/dev/root,fs=cramfs,flags=32769

VFS: Mounted root (cramfs filesystem) readonly.

Freeing init memory: 104K

Reading data from NAND FLASH without ECC is not recommended

init started: BusyBox v1.10.1 (2008-04-23 23:20:41 CST)

starting pid 229, tty '': '/etc/init.d/rcS'

Reading data from NAND FLASH without ECC is not recommended

the error code is:0,name=/dev/root,fs=cramfs,flags=32769

VFS: Mounted root (cramfs filesystem) readonly.

Freeing init memory: 104K

Reading data from NAND FLASH without ECC is not recommended

init started: BusyBox v1.10.1 (2008-04-23 23:20:41 CST)

starting pid 229, tty '': '/etc/init.d/rcS'

Please press Enter to activate this console.

4. 系统启动到到如下语句即停止不前，停在那里：

VFS:Mounted root (cramfs filesystem) readonly.

Freeing init memory:104

卡在这里没有下文

原因分析：系统在启用init函数时有这么一句，粗体所示

static int init(void * unused)

{

if(execute_command)

{

run_init_process(execute_command);

}

………………

｝

在这句里面出错就会没有下文

解决办法：在配置内核时少选了几句，将如下选择全选上

Floating Point emulation

->At least one emulation must be selected:

NWFPE math emulation

Support extended precision

FastFPE math emulation(EXPERIMENTAL)

5. 关于文件系统问题：在有些资料上提到在配置内核时选上devfs，如果不存在时则手动在文件里加上。但我在内核里面和busybox-1.10.1中都未加devfs支持文件系统运行正常。在linux-2.6.14.1及以后版本中已去掉devfs。

6. linux-2.6.15.4这个版本也能成功在s3c2410上运行.

内核编译成功后，启动后出现如下提示后就停住了。。。。。。
Freeing init memory: 72K
Warning: unable to open an initial console.

!C+Q7f W ][0这个也是控制台console的问题，linux-2.6.13以后的内核都支持devfs，而之后版本的内核就把devfs这块去掉了，虽然还能在内核源码中找到对应的源码，你也可以把它加进内核，但是也不是太好用。2.6.13 后的版本改为支持udev了，udev这块我也没太弄懂，正在研究。-

--> Kernel Features
   --> Preemption Mode

.config 里面的 CONFIG_PREEMPT_NONE 选项决定了kernel在挂在文件系统后可不能进入shell。

-------------------------------------------------------------------------------

--> Floating point emulation
FPE_NWFPE 选项如果未选上
现象：
…………
IPv4 over IPv4 tunneling driver
TCP bic registered
NET: Registered protocol family 1
IP-Config: No network devices available.
RAMDISK: ext2 filesystem found at block 0
RAMDISK: Loading 4196KiB [1 disk] into ram disk... done.
EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
VFS: Mounted root (ext2 filesystem).
Freeing init memory: 96K
kernel 启动到这里就停止了。
-------------------------------------------------------------------------
--> Device Drivers
   --> Block devices
CONFIG_BLK_DEV_RAM选项  未选上
CONFIG_BLK_DEV_INITRD选项  未选上
现象：
………………
loop: loaded (max 8 devices)
nbd: registered device at major 43
mice: PS/2 mouse device common for all mice
IPv4 over IPv4 tunneling driver
TCP bic registered
NET: Registered protocol family 1
IP-Config: No network devices available.
Root-NFS: No NFS server available, giving up.
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "ram0" or unknown-block(2,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)

1. 加载kernel后出现如下错误：
NET: Registered protocol family 1
Root-NFS: No NFS server available, giving up.
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "mtdblock3" or unknown-block(2,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
其中，linux command line is: "noinitrd root=/dev/mtdblock3 init=/linuxrc console=ttySAC0,115200"
解决方法，在make menuconfig 后，选中mtd支持，cramfs支持，/dev fs支持。
其中，添加/dev fs支持具体操作如下:
修改fs/Kconfig，支持启动时挂载devfs
$vim fs/ Kconfig
找到menu “Pseudo filesystem”
在其中添加：
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

   之后，boot信息如下：

boot
Copy linux kernel from 0x00030000 to 0x30008000, size = 0x00100000 ... done
zImage magic = 0x016f2818
Setup linux parameters at 0x30000100
linux command line is: "noinitrd root=/dev/mtdblock/3 init=/linuxrc console=ttySAC0,115200"
MACH_TYPE = 193
NOW, Booting Linux......
Uncompressing Linux................................................................... done, booting the kernel.
Linux version 2.6.15.4 ([e-mail]) (gcc version 4.1.1) #5 Thu Aug 2 20:47:27 CST 2007
CPU: ARM920Tid(wb) [41129200] revision 0 (ARMv4T)
Machine: SMDK2410
ATAG_INITRD is deprecated; please update your bootloader.
Memory policy: ECC disabled, Data cache writeback
CPU S3C2410A (id 0x32410002)
S3C2410: core 200.000 MHz, memory 100.000 MHz, peripheral 50.000 MHz
S3C2410 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
Kernel command line: noinitrd root=/dev/mtdblock/3 init=/linuxrc console=ttySAC0,115200
irq: clearing subpending status 00000007
irq: clearing subpending status 00000002
PID hash table entries: 256 (order: 8, 4096 bytes)
timer tcon=00000000, tcnt a2c1, tcfg 00000200,00000000, usec 00001eb8
Console: colour dummy device 80x30
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 32MB = 32MB total
Memory: 30248KB available (1676K code, 376K data, 88K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
NET: Registered protocol family 16
S3C2410: Initialising architecture
S3C2410 DMA Driver, (c) 2003-2004 Simtec Electronics
DMA channel 0 at c2800000, irq 33
DMA channel 1 at c2800040, irq 34
DMA channel 2 at c2800080, irq 35
DMA channel 3 at c28000c0, irq 36
NetWinder Floating Point Emulator V0.97 (extended precision)
devfs: 2004-01-31 Richard Gooch ([e-mail])
devfs: devfs_debug: 0x0                                                                        //可以看出，已经支持devfs
devfs: boot_options: 0x1                                                                                          
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered
Console: switching to colour frame buffer device 80x25
fb0: Virtual frame buffer device, using 1024K of video memory
s3c2410-uart.0: s3c2410_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2410
s3c2410-uart.1: s3c2410_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2410
s3c2410-uart.2: s3c2410_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2410
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
S3C24XX NAND Driver, (c) 2004 Simtec Electronics
s3c2410-nand: Tacls=1, 10ns Twrph0=4 40ns, Twrph1=1 10ns
NAND device: Manufacturer ID: 0xec, Chip ID: 0x75 (Samsung NAND 32MiB 3,3V 8-bit)
NAND_ECC_NONE selected by board driver. This is not recommended !!
Scanning device for bad blocks
Creating 5 MTD partitions on "NAND 32MiB 3,3V 8-bit":
0x00000000-0x00020000 : "loader"
0x00020000-0x00030000 : "param"
0x00030000-0x001f0000 : "kernel"
0x00200000-0x00600000 : "root"
0x00600000-0x04000000 : "user"
mtd: partition "user" extends beyond the end of device "NAND 32MiB 3,3V 8-bit" -- size truncated to 0x1a00000
mice: PS/2 mouse device common for all mice
NET: Registered protocol family 2
IP route cache hash table entries: 512 (order: -1, 2048 bytes)
TCP established hash table entries: 2048 (order: 1, 8192 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
TCP bic registered
NET: Registered protocol family 1
Root-NFS: No NFS server available, giving up.
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "mtdblock/3" or unknown-block(2,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)

     根据网上的一些指导，将linux_cmd_line设置为"noinitrd root=/dev/mtdblock/3 init=/linuxrc console=ttySAC0,115200"，问题
依旧。尝试了几乎所有网上的办法，问题没有得到解决。于是尝试换一个内核，下载了2.6.22的内核，按照2.6.15.4一样
配置编译了内核，当然，该版本的移植步骤有点变化，最主要的区别是，2.6.22的内核已经没有了/arch/arm/mach-s3c2410/dev.c文件，
所以，分区信息要在arch/arm/mach-s3c2410/common-smdk.c中修改static struct mtd_partition smdk_default_nand_part[] 。
boot后：

boot
Copy linux kernel from 0x00030000 to 0x30008000, size = 0x001d0000 ... done
zImage magic = 0x016f2818
Setup linux parameters at 0x30000100
linux command line is: "noinitrd root=/dev/mtdblock3 init=/linuxrc console=ttySAC0,115200"
MACH_TYPE = 193
NOW, Booting Linux......
Uncompressing Linux.................................................................................................. done, booting the kernel.
Linux version 2.6.22 ([e-mail]) (gcc version 4.1.1) #3 Sun Aug 5 16:00:32 CST 2007
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 S3C2410A (id 0x32410002)
S3C2410: core 200.000 MHz, memory 100000 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.  Total pages: 8128
Kernel command line: noinitrd root=/dev/mtdblock3 init=/linuxrc console=ttySAC0,115200
irq: clearing subpending status 00000007
irq: clearing subpending status 00000002
PID hash table entries: 128 (order: 7, 512 bytes)
timer tcon=00000000, tcnt a2c1, tcfg 00000200,00000000, usec 00001eb8
Console: colour dummy device 80x30
Dentry cache hash table entries: 4096 (order: 2, 16384 bytes)
Inode-cache hash table entries: 2048 (order: 1, 8192 bytes)
Memory: 32MB = 32MB total
Memory: 29224KB available (2780K code, 309K data, 132K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
NET: Registered protocol family 16
S3C2410 Power Management, (c) 2004 Simtec Electronics
S3C2410: Initialising architecture
S3C24XX DMA Driver, (c) 2003-2004,2006 Simtec Electronics
DMA channel 0 at c2800000, irq 33
DMA channel 1 at c2800040, irq 34
DMA channel 2 at c2800080, irq 35
DMA channel 3 at c28000c0, 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: 1024 (order: 1, 8192 bytes)
TCP bind hash table entries: 1024 (order: 0, 4096 bytes)
TCP: Hash tables configured (established 1024 bind 1024)
TCP reno registered
NetWinder Floating Point Emulator V0.97 (double precision)
JFFS2 version 2