Vfs:cannot Open Root Device "Mtdblock2" or Unknown-block (0,0)

Porting the Linux kernel to the Development Board today is really a problem, first of all, the machine code is wrong, and then the NIC driver is wrong, followed by a file system regardless of the mount, thanks to many netizens in the online generous contribution of their own transplant process experience, let me finally adhere to go on. Below I also share the following solution:

Start Linux ...

Copy Linux kernel from 0x00240000 to 0x30008000, size = 0x00200000 ... Copy Kernel to SDRAM done,now, booting Linux ...

Uncompressing Linux ....................................................................................................................... Done, booting the kernel.
Linux version 2.6.30.4-gtstudio (root@localhost.localdomain) (GCC version 4.3.3 (sourcery g++ Lite 2009q1-203)) #1 Sun Au G 4 17:27:48 CST 2013
cpu:arm920t [41129200] revision 0 (ARMV4T), cr=c0007177
CPU:VIVT data cache, VIVT instruction cache
machine:gt2440
ATAG_INITRD is deprecated; Please update your bootloader.
Memory POLICY:ECC Disabled, Data cache writeback
CPU s3c2440a (ID 0x32440001)
s3c24xx clocks, (c) 2004 Simtec Electronics
S3c244x:core 400.000 MHz, memory 100.000 MHz, peripheral 50.000 MHz
Clock:slow mode (1.500 MHz), fast, MPLL on, UPLL on
Built 1 zonelists in Zone order, mobility grouping on. Total pages:16256
Kernel command LINE:NOINITRD root=/dev/mtdblock2 INIT=/LINUXRC console=ttysac0
Nr_irqs:85
Irq:clearing Pending EXT Status 00000200
irq:clearing subpending Status 00000003
irq:clearing subpending Status 00000002
PID Hash Table entries:256 (order:8, 1024x768 bytes)
Console:colour Dummy Device 80x30
console [ttySAC0] 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:60956KB available (3432K code, 374K data, 104K init, 0K highmem)
slub:genslabs=11, hwalign=32, order=0-3, Minobjects=0, Cpus=1, Nodes=1
Calibrating delay loop ... 199.47 bogomips (lpj=498688)
Mount-cache Hash Table entries:512
Cpu:testing Write Buffer Coherency:ok
net_namespace:296 bytes
Net:registered Protocol Family 16
S3c2440:initialising Architecture
S3C2440:IRQ Support
S3c24xx DMA Driver, (c) 2003-2004,2006 Simtec Electronics
DMA Channel 0 at c4808000, IRQ 33
DMA Channel 1 at c4808040, IRQ 34
DMA Channel 2 at c4808080, IRQ 35
DMA Channel 3 at C48080C0, IRQ 36
S3c244x:clock support, DVS off
Bio:create Slab <bio-0> at 0
SCSI subsystem Initialized
Usbcore:registered New Interface Driver USBFS
Usbcore:registered New Interface Driver hub
usbcore:registered New device driver USB
S3C2440-I2C S3c2440-i2c:slave Address 0x10
S3C2440-I2C S3c2440-i2c:bus Frequency set to + KHz
S3C2440-I2C s3c2440-i2c:i2c-0: s3c i²c Adapter
cfg80211:calling Crda to update World regulatory domain
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
Net:registered Protocol Family 1
Yaffs 4 17:24:00 Installing.
Msgmni have been set to 119
Alg:no test for STDRNG (KRNG)
IO Scheduler NoOp registered (default)
LEDs initialized
Buttons initialized
ADC initialized
S3c2440-uart.0:s3c2410_serial0 at MMIO 0x50000000 (IRQ = All) is a s3c2440
S3c2440-uart.1:s3c2410_serial1 at MMIO 0x50004000 (IRQ = $) is a s3c2440
S3c2440-uart.2:s3c2410_serial2 at MMIO 0x50008000 (IRQ = ON) is a s3c2440
Loop:module Loaded
Driver ' SD ' needs updating-please use bus_type methods
Cs89x0:cs89x0_probe (0x0)
Cs89x0.c:v2.4.3-pre1 Russell Nelson <nelson@crynwr.com&gt, Andrew Morton
eth0:cs8900 Rev J found at 0xc4a00300
cs89x0:extended EEPROM checksum Bad and no Cirrus EEPROM, relying on command line
Cs89x0 Media IRQ, programmed I/O, MAC 08:89:89:89:89:89
CS89X0_PROBE1 () successful
S3c24xx NAND Driver, (c) 2004 Simtec Electronics
S3c2440-nand s3c2440-nand:tacls=3, 30ns twrph0=7 70ns, twrph1=3 30ns
NAND device:manufacturer id:0xec, Chip id:0xda (Samsung NAND 256MiB 3,3v 8-bit)
Scanning device for bad blocks
Bad Eraseblock 162 at 0x000001440000
Bad Eraseblock 219 at 0x000001b60000
Bad Eraseblock 581 at 0x0000048a0000
Bad Eraseblock 1322 at 0x00000a540000
OHCI_HCD:USB 1.1 ' Open ' Host Controller (OHCI) Driver
S3C2410-OHCI s3c2410-ohci:s3c24xx OHCI
S3C2410-OHCI s3c2410-ohci:new USB Bus registered, assigned bus number 1
S3C2410-OHCI S3c2410-ohci:irq, io mem 0x49000000
USB usb1:new USB device found, idvendor=1d6b, idproduct=0001
USB usb1:new USB Device strings:mfr=3, product=2, serialnumber=1
USB Usb1:Product:S3C24XX OHCI
USB Usb1:Manufacturer:Linux 2.6.30.4-gtstudio OHCI_HCD
USB usb1:SerialNumber:s3c24xx
USB Usb1:configuration #1 chosen from 1 choice
Hub 1-0:1.0:USB Hub found
Hub 1-0:1.0:2 Ports detected
Initializing USB Mass Storage driver ...
Usbcore:registered New Interface Driver Usb-storage
USB Mass Storage support registered.
Usbcore:registered New Interface Driver usbserial
USBSERIAL:USB Serial Driver Core
USB Serial support registered for pl2303
Usbcore:registered New Interface Driver pl2303
Pl2303:prolific PL2303 USB to serial adaptor driver
S3c2410_udc:debugfs dir creation failed-19
S3c2440-usbgadget s3c2440-usbgadget:s3c2440:increasing FIFO to bytes
MICE:PS/2 mouse device common for all mice
GT2440 touchscreen successfully loaded
input:gt2440 touchscreen as/devices/virtual/input/input0
S3c24xx RTC, (c) 2004,2006 Simtec Electronics
S3C2410-RTC S3C2410-RTC:RTC Disabled, re-enabling
S3C2410-RTC S3C2410-RTC:RTC core:registered s3c as Rtc0
I2c/dev Entries Driver
Linux Video Capture interface:v2.00
ZC0301:V4L2 driver for Zc0301[p] Image Processor and Control Chip v1:1.10
Usbcore:registered New Interface Driver zc0301
Gspca:main v2.5.0 Registered
Usbcore:registered New Interface Driver zc3xx
Zc3xx:registered
Usbcore:registered New Interface Driver Uvcvideo
USB Video Class Driver (v0.1.0)
s3c2410 Watchdog Timer, (c) 2004 Simtec Electronics
S3C2410-WDT s3c2410-wdt:watchdog Inactive, reset disabled, IRQ enabled
S3C2440-SDI S3c2440-sdi:host detect has no IRQ available
Mapped channel 0 to 0
S3C2440-SDI s3c2440-sdi:powered down.
S3C2440-SDI s3c2440-sdi:initialisation done.
S3C2440-SDI s3c2440-sdi:running at 0kHz (requested:0khz).
S3C2440-SDI s3c2440-sdi:running at 196kHz (requested:195khz).
S3C2440-SDI s3c2440-sdi:running at 196kHz (requested:195khz).
S3C2440-SDI s3c2440-sdi:running at 196kHz (requested:195khz).
S3C2440-SDI s3c2440-sdi:powered down.
Usbcore:registered New Interface Driver Usbhid
USBHID:V2.6:USB HID Core Driver
Advanced Linux Sound Architecture Driver Version 1.0.20.
No Device for DAI uda134x
No Device for DAI s3c24xx-i2s
s3c24xx_uda134x SoC Audio Driver
uda134x SoC Audio Codec
asoc:uda134x <-> s3c24xx-i2s Mapping OK
ALSA Device List:
#0: s3c24xx_uda134x (uda134x)
TCP Cubic Registered
Rpc:registered UDP Transport module.
Rpc:registered TCP Transport module.
Lib80211:common Routines for IEEE802.11 drivers
S3C2410-RTC s3c2410-rtc:setting system clock to 2009-03-05 18:52:59 UTC (1236279179)
Root-nfs:no NFS server available, giving up.
Vfs:unable to mount Root FS via NFS, trying floppy.
Vfs:cannot Open Root Device "Mtdblock2" or Unknown-block (2,0)
Please append a correct "root=" boot option; Here is the available partitions:
1F00 262144 mtdblock0 (driver?)
Kernel Panic-not syncing:VFS:Unable to mount Root fs on Unknown-block (2,0)
BackTrace:
[<c0026fd4>] (dump_backtrace+0x0/0x10c) from [<c029bbfc>] (dump_stack+0x18/0x1c)
R7:C380A0CB r6:c03a8060 r5:c380a000 R4:c381df40
[<c029bbe4>] (dump_stack+0x0/0x1c) from [<c029bc4c>] (panic+0x4c/0x124)
[<c029bc00>] (panic+0x0/0x124) from [<c0008e30>] (mount_block_root+0x178/0x234)
r3:00000000 R2:c38553ec R1:c381df40 r0:c03298a8
[<c0008cb8>] (mount_block_root+0x0/0x234) from [<c0008f9c>] (MOUNT_ROOT+0XB0/0XF4)
[<c0008eec>] (Mount_root+0x0/0xf4) from [<c00090d8>] (prepare_namespace+0xf8/0x18c)
R7:c03a7a44 r6:c001e83c r5:c001e83c r4:c001e84c
[<c0008fe0>] (prepare_namespace+0x0/0x18c) from [<c0008478>] (KERNEL_INIT+0XC8/0XF4)
r7:00000000 R6:C001DDF4 r5:c001da9c R4:c001ddf4
[<c00083b0>] (Kernel_init+0x0/0xf4) from [<c0037f30>] (do_exit+0x0/0x620)
r7:00000000 r6:00000000 r5:00000000 r4:00000000

First, I compare this code with the normal Linux boot code and find two missing places that are already marked in the startup code:

1.yaffs may31,2006 Installing

2.

Creating 3 MTD partitions on "NAND256MB 3,3v 8-bit":

0x000000000000-0x000000080000: "Uboot"

0x000000240000-0x000000640000: "Kernel"

0x000000440000-0x000010000000: "YAFFS2" to the online search, there are probably two kinds of statements:

1, yaffs file system is not configured successfully, file system->miscellaneous files systems->yaffs2 file Systemsupport is configured in front of "M", not "*", The error is due to the wrong configuration here. The previous configuration of the kernel when the configuration as "M" and "*" is not affected, the original is wrong, some configuration must be "*", the system can start normally.

2. Configure device drivers, Memory technology device (MTD) support to "*" while at device drivers, memory technology device (MTD ) Support--->

There's an option in there: Caching block device access to MTD devices, which also needs to be configured as "*" however, neither of these scenarios solves my problem because I'm worried that my kconfig file is not written right, So in the compiled Linux kernel directory under the FS/YAFFS2 directory under the view, found that there is a YAFFS_FS.O file, which proves that my linxu kernel has added support for YAFFS2 files, but why does not show Creating 3 MTD Partitions on "nand256mb3,3v 8-bit": this sentence. is very tangled, so carefully looked at my comm-gt2440.c file, and then compared with other people's files, found less NAND flash configuration:

static struct Mtd_partition smdk_default_nand_part[] = {

#if defined (Config_64m_nand)

[0] = {

. Name = "Boot",

. Offset = 0,

. Size = sz_1m,

},

[1] = {

. Name = "Kernel",

. offset = sz_1m + sz_128k,

. Size = sz_4m,

},

[2] = {

. Name = "YAFFS2",

. offset = sz_1m + sz_128k + sz_4m,

. Size = sz_64m-sz_4m-sz_1m-sz_128k,

}

#elif defined (Config_256m_nand)

[0] = {

. Name = "Boot",

. Offset = 0,

. Size = sz_1m,

},

[1] = {

. Name = "Kernel",

. offset = sz_1m + sz_128k,

. Size = sz_4m,

},

[2] = {

. Name = "YAFFS2",

. offset = sz_1m + sz_128k + sz_4m,

. Size = sz_256m-sz_4m-sz_1m-sz_128k,

}

#endif};

However, remember that my configuration is placed in the plat-s3c24xx file directory, so to the directory under the view of the following COMMON-GTSTUDIO.C file has the following NAND flash initialization configuration:

static struct Mtd_partition gtstudio_default_nand_part[] = {
#if defined (Config_gtstudio_64mb_nand)
[0] = {
. Name = "Uboot",
. offset = 0x00000000,
. Size = 0x00040000,
},
[1] = {
. Name = "Kernel",
. offset = 0x00200000,
. Size = 0x00200000,
},
[2] = {
. Name = "YAFFS2",
. offset = 0x00200000,
. Size = 0x03bf8000,
}
#elif defined (Config_gtstudio_more_than_256mb_nand)
[0] = {
. Name = "Uboot",
. offset = 0x00000000,
. Size = 0x00080000,
},
[1] = {
. Name = "Kernel",
. offset = 0x00240000,
. Size = 0x00200000,
},
[2] = {
. Name = "YAFFS2",
. offset = 0x00440000,
. Size = 0x0fb40000,
}
#endif
};

But here the uboot,kernel,yaffs2 words let me have a familiar hurry, this is not the boot code missing 3 MTD blocks. The problem is then targeted to the Config_gtstudio_more_than_256mb_nand

Definition, obviously, my Linux kernel does not have this macro definition, so add the following definition, as follows:

->CD Linux-2.6.30.4/drivers/mtd/nand

->vi Kconfig

; Jump to line 165, edit to add the following configuration:

Choice
Prompt "Nand Flash capacity Select"
Depends on MTD
Help
Gtstudio Board Nand Flash Capacity Select

Config Gtstudio_64mb_nand
Boolean "64MB Nand for Gtstudio Board"
Depends on MTD
Help
Set 64MB Nand Parts

Config Gtstudio_more_than_256mb_nand
Boolean "256MB~1GB Nand for Gtstudio Board"
Depends on MTD
Help
Set 256MB~1GB Nand Parts

Endchoice

->CD. /.. /.. /.. /; Configure Linux kernel add 256MB NAND flash support

->make Menuconfig Arch=arm

Select NAND under Device drivers->momory technology Device (MTD) Support->nand device support->s3c2410 NAND hardware ECC Flash capacity Select, also select 256MB~1GB Nand for Gtstudio Board,ok, recompile, everything Ok.