Getting error "VFS: Cannot open root device "mmcblk0p2" or unknown-block(179,2)" while booting from SD card, DVSDK 4.X, platform: DM36X

It does seem odd that u-boot, boot.scr and the linux kernel can be read from parition 1 but filesystem cannot be read from partition 2. Eveyrthing looks to be okay except for the "(ro)" part of the line

mmcblk0: mmc0:e624 SD08G 7.40 GiB (ro)

I think that means the driver thinks the card is read-only. The root file system needs to writeable. Check the lock switch on the card. You might have to trace the Write Protect signal from the socket to the processor. I am not familiar with the DM365 EVM. Maybe you need to reseat some boards. Maybe something got enabled in the kernel that is taking over that pin.

Hi Wong,

     Thanks for you reply.

     I do realize that the ro mark during boot is not correct, I confirmed this by looking at older traces i archived. But Regardless of what ever the switch setting be now i always see SD card be recognized as ro.

    It is the same old kernel iam using.

     It sounds like my EVM is dead exactly at write protect pin,

Thanks & Regards

Velan

Hi Velan,

    Please let me know if you had any solution on this.

Regards,

Amit

You might be able to configure the MMC driver to ignore the CD and WP pins. You would need to change some initializers in your board.c file from

   .gpio_cd = GPIO_TO_PIN(0, 6),
   .gpio_wp = GPIO_TO_PIN(3, 18),
to
   .nonremovable = true;
   .gpio_cd = -EINVAL;
   .gpio_wp = -EINVAL;

Ideally the root cause should be found. Always the possibiliy that it a symptom of more serious problems,

having the same problem too.

it's like this issue comes up from nowhere.

Just experienced this same problem.

I had dd'd an existing SD-Card that was working perfectly; it was a Micro SD-Card with an adaptor.

The new SD-Card (again, Micro with adaptor) exhibited the issue.

Tried re-imaging with dd a few times to no avail.

After reading threads on the issue, checked the write-protect slider on the adaptor and it all seemed okay; then swapped the Micro SD into the original adaptor, and it worked.

It turned out that the write-protect slider on the SD Card pushes a tiny pin onto another tiny metal flap on the am335x EVM board and that closes a circuit.  If the write-protect slider is not "thick" enough, it wasn't pushing the pin far enough to make connection.

By gently bending the flap down a little (on the am335x) this solved the problem.

HTH.

Hi all,

I'm experiencing the same problem.But i'm not getting ro message error.Here is my log.

Please help.

ø

Texas Instruments X-Loader 1.46 (May 11 2011 - 19:45:24)


U-Boot 2009.11 (May 30 2011 - 22:50:27)

OMAP34xx/35xx-GP ES1.0, CPU-OPP2 L3-165MHz
VAR-SOM-AM35xx Board + LPDDR/NAND
I2C:   ready
DRAM:  256 MB
NAND:  256 MiB
In:    serial
Out:   serial
Err:   serial
Die ID #0f840001000000000146876c1500400c
Net:   davinci_emac_initialize
Ethernet PHY: GENERIC @ 0x00
DaVinci EMAC
VAR-SOM-AM35 # mmc i it
mmc - MMC sub-system

Usage:
mmc init [dev] - init MMC sub system
mmc device [dev] - show or set current device
VAR-SOM-AM35 # mmc init
mmc1 is available
VAR-SOM-AM35 # fatload mmc 0 0x82000000 boot,scr .scr
reading boot.scr

461 bytes read
VAR-SOM-AM35 # source 0x82000000
## Executing script at 82000000
reading uImage

3047956 bytes read
***** Kernel: /dev/mmcblk0p1/uImage *****
***** RootFS: /dev/mmcblk0p2 *****
## Booting kernel from Legacy Image at 82000000 ...
   Image Name:   Linux-2.6.37-g06ebbba
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    3047892 Bytes =  2.9 MB
   Load Address: 80008000
   Entry Point:  80008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK

Starting kernel ...

Uncompressing Linux... done, booting the kernel.
Linux version 2.6.37-g06ebbba (a0131746@swubn01) (gcc version 4.4.3 (GCC) ) #1 Fri Jul 8 02:47:41 IST 2011
CPU: ARMv7 Processor [411fc087] revision 7 (ARMv7), cr=10c53c7f
CPU: VIPT nonaliasing data cache, VIPT nonaliasing instruction cache
Machine: OMAP3517/AM3517 EVM
Reserving 8388608 bytes SDRAM for VRAM
Memory policy: ECC disabled, Data cache writeback
AM3517 ES1.1 (l2cache sgx neon isp )
SRAM: Mapped pa 0x40200000 to va 0xfe400000 size: 0x10000
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 62976
Kernel command line: console=ttyO2,115200n8 androidboot.console=ttyO2
mem=256M root=/dev/mmcblk0p2 rw rootfstype=ext3 rootdelay=1 init=/init
ip=off omap_vout.vid1_static_vrfb_alloc=y vram=8M omapfb.vram=0:8M
PID hash table entries: 1024 (order: 0, 4096 bytes)
Dentry cache hash table entries: 32768 (order: 5, 131072 bytes)
Inode-cache hash table entries: 16384 (order: 4, 65536 bytes)
Memory: 248MB = 248MB total
Memory: 244708k/244708k available, 17436k reserved, 0K highmem
Virtual kernel memory layout:
    vector  : 0xffff0000 - 0xffff1000   (   4 kB)
    fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
    DMA     : 0xffc00000 - 0xffe00000   (   2 MB)
    vmalloc : 0xd0800000 - 0xf8000000   ( 632 MB)
    lowmem  : 0xc0000000 - 0xd0000000   ( 256 MB)
    modules : 0xbf000000 - 0xc0000000   (  16 MB)
      .init : 0xc0008000 - 0xc003d000   ( 212 kB)
      .text : 0xc003d000 - 0xc05bf000   (5640 kB)
      .data : 0xc05c0000 - 0xc0603940   ( 271 kB)
NR_IRQS:375
Clocking rate (Crystal/Core/MPU): 26.0/332/600 MHz
Reprogramming SDRC clock to 332000000 Hz
dpll3_m2_clk rate change failed: -22
IRQ: Found an INTC at 0xfa200000 (revision 4.0) with 96 interrupts
Total of 96 interrupts on 1 active controller
GPMC revision 5.0
Trying to install interrupt handler for IRQ368
Trying to install interrupt handler for IRQ369
Trying to install interrupt handler for IRQ370
Trying to install interrupt handler for IRQ371
Trying to install interrupt handler for IRQ372
Trying to install interrupt handler for IRQ373
Trying to install interrupt handler for IRQ374
Trying to install type control for IRQ375
Trying to set irq flags for IRQ375
OMAP clockevent source: GPTIMER1 at 32768 Hz
Console: colour dummy device 80x30
Calibrating delay loop... 597.64 BogoMIPS (lpj=2334720)
pid_max: default: 32768 minimum: 301
Security Framework initialized
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
regulator: core version 0.5
regulator: dummy:
NET: Registered protocol family 16
OMAP GPIO hardware version 2.5
OMAP GPIO hardware version 2.5
OMAP GPIO hardware version 2.5
OMAP GPIO hardware version 2.5
OMAP GPIO hardware version 2.5
OMAP GPIO hardware version 2.5
omap_mux_init: Add partition: #1: core, flags: 0
Display initialized successfully
_omap_mux_init_gpio: Multiple gpio paths (2) for gpio126
Found NOR on CS1
Registering NOR on CS1
hw-breakpoint: debug architecture 0x4 unsupported.
OMAP DMA hardware revision 4.0
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
omap_device: omap_i2c.1: new worst case activate latency 0: 30517
omap_i2c omap_i2c.1: bus 1 rev3.12 at 400 kHz
omap_device: omap_i2c.1: new worst case deactivate latency 0: 30517
omap_i2c omap_i2c.2: bus 2 rev3.12 at 400 kHz
pca953x 2-0021: failed reading register
pca953x: probe of 2-0021 failed with error -121
omap_i2c omap_i2c.3: bus 3 rev3.12 at 400 kHz
tca6416-keypad 3-0020: tca6416_read_reg failed, reg: 1, error: -121
tca6416-keypad: probe of 3-0020 failed with error -121
pca953x 3-0021: failed reading register
pca953x: probe of 3-0021 failed with error -121
Advanced Linux Sound Architecture Driver Version 1.0.23.
Switching to clocksource 32k_counter
musb-hdrc: version 6.0, otg (peripheral+host), debug=0
musb-hdrc musb-hdrc.0: dma type: pio
<6>Waiting for PHY clock good...
musb-hdrc musb-hdrc.0: USB OTG mode controller at d0810000 using PIO, IRQ 71
NET: Registered protocol family 2
IP route cache hash table entries: 2048 (order: 1, 8192 bytes)
TCP established hash table entries: 8192 (order: 4, 65536 bytes)
TCP bind hash table entries: 8192 (order: 3, 32768 bytes)
TCP: Hash tables configured (established 8192 bind 8192)
TCP reno registered
UDP hash table entries: 256 (order: 0, 4096 bytes)
UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
NET: Registered protocol family 1
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
RPC: Registered tcp NFSv4.1 backchannel transport module.
NetWinder Floating Point Emulator V0.97 (double precision)
omap_init_opp_table: no hwmod or odev for iva, [9] cannot add OPPs.
AM3517  Linux PSP version 04.02.00.07 (AM3517EVM)
ashmem: initialized
VFS: Disk quotas dquot_6.5.2
Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
JFFS2 version 2.2. (NAND) (SUMMARY)  © 2001-2006 Red Hat, Inc.
msgmni has been set to 477
io scheduler noop registered
io scheduler deadline registered
io scheduler cfq registered (default)
OMAP DSS rev 2.0
omapdss supply vdds_dsi not found, using dummy regulator
OMAP DISPC rev 3.0
omapdss supply vdda_dac not found, using dummy regulator
OMAP VENC rev 2
OMAP DSI rev 1.0
Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
omap_uart.0: ttyO0 at MMIO 0x4806a000 (irq = 72) is a OMAP UART0
omap_uart.1: ttyO1 at MMIO 0x4806c000 (irq = 73) is a OMAP UART1
omap_uart.2: ttyO2 at MMIO 0x49020000 (irq = 74) is a OMAP UART2
console [ttyO2] enabled
brd: module loaded
loop: module loaded
mtdoops: mtd device (mtddev=name/number) must be supplied
physmap platform flash device: 08000000 at 08000000
physmap-flash physmap-flash.0: map_probe failed
omap2-nand driver initializing
NAND device: Manufacturer ID: 0x2c, Chip ID: 0xca (Micron )
Creating 5 MTD partitions on "omap2-nand.0":
0x000000000000-0x000000080000 : "xloader-nand"
0x000000080000-0x000000240000 : "uboot-nand"
0x000000240000-0x000000280000 : "params-nand"
0x000000280000-0x000000780000 : "linux-nand"
0x000000780000-0x000010000000 : "jffs2-nand"
davinci_mdio davinci_mdio: davinci mdio revision 1.5
davinci_mdio davinci_mdio: detected phy mask fffffffc
davinci_mdio: probed
davinci_mdio davinci_mdio: phy[0]: device ffffffff:00, driver unknown
davinci_mdio davinci_mdio: phy[1]: device ffffffff:01, driver unknown
usbcore: registered new interface driver cdc_ether
usbcore: registered new interface driver dm9601
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
ehci-omap.0 supply hsusb0 not found, using dummy regulator
ehci-omap ehci-omap.0: OMAP-EHCI Host Controller
ehci-omap ehci-omap.0: new USB bus registered, assigned bus number 1
ehci-omap ehci-omap.0: irq 77, io mem 0x48064800
ehci-omap ehci-omap.0: USB 2.0 started, EHCI 1.00
usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: OMAP-EHCI Host Controller
usb usb1: Manufacturer: Linux 2.6.37-g06ebbba ehci_hcd
usb usb1: SerialNumber: ehci-omap.0
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 3 ports detected
Initializing USB Mass Storage driver...
usbcore: registered new interface driver usb-storage
USB Mass Storage support registered.
usbcore: registered new interface driver usbtest
android init
android_probe pdata: c05d01bc
android_bind
android_usb gadget: android_usb ready
musb-hdrc musb-hdrc.0: MUSB HDRC host driver
musb-hdrc musb-hdrc.0: new USB bus registered, assigned bus number 2
usb usb2: New USB device found, idVendor=1d6b, idProduct=0002
usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb2: Product: MUSB HDRC host driver
usb usb2: Manufacturer: Linux 2.6.37-g06ebbba musb-hcd
usb usb2: SerialNumber: musb-hdrc.0
hub 2-0:1.0: USB hub found
hub 2-0:1.0: 1 port detected
f_acm init
android_register_function acm
f_adb init
android_register_function adb
adb_bind_config
f_mass_storage init
android_register_function usb_mass_storage
f_mtp init
android_register_function mtp
mice: PS/2 mouse device common for all mice
tsc2004: probe of 1-004b failed with error -121
rtc-s35390a 1-0030: error resetting chip
rtc-s35390a: probe of 1-0030 failed with error -5
i2c /dev entries driver
Linux video capture interface: v2.00
usbcore: registered new interface driver uvcvideo
USB Video Class driver (v1.0.0)
vpfe_init
vpfe-capture vpfe-capture: v4l2 device registered
vpfe-capture vpfe-capture: video device registered
tvp514x 3-005c: tvp514x 3-005c decoder driver registered !!
tvp514x 3-005c: Write: retry ... 0
tvp514x 3-005c: Write: retry ... 1
tvp514x 3-005c: Write: retry ... 2
tvp514x 3-005c: Write: retry ... 3
tvp514x 3-005c: Write: retry ... 4
tvp514x 3-005c: Write: retry ... 5
tvp514x 3-005c: Write failed. Err[-121]
tvp514x 3-005c: Unable to turn on decoder
tvp514x 3-005c: Read: retry ... 0
tvp514x 3-005c: Read: retry ... 1
tvp514x 3-005c: Read: retry ... 2
tvp514x 3-005c: Read: retry ... 3
tvp514x 3-005c: Read: retry ... 4
tvp514x 3-005c: Read: retry ... 5
tvp514x 3-005c: Unable to query std
vpfe-capture vpfe-capture: v4l2 sub device tvp5146 registered
vpfe_register_ccdc_device: DM6446 CCDC
DM6446 CCDC is registered with vpfe.
omap_device: omap_wdt.-1: new worst case activate latency 0: 30517
OMAP Watchdog Timer Rev 0x31: initial timeout 60 sec
device-mapper: uevent: version 1.0.3
device-mapper: ioctl: 4.18.0-ioctl (2010-06-29) initialised: dm-devel@redhat.com
usbcore: registered new interface driver usbhid
usbhid: USB HID core driver
logger: created 64K log 'log_main'
logger: created 256K log 'log_events'
logger: created 64K log 'log_radio'
logger: created 64K log 'log_system'
usbcore: registered new interface driver snd-usb-audio
OMAP3517 / AM3517 EVM SoC init
AIC23 Audio Codec 0.1
tlv320aic23_write cannot write 000 to register R15
tlv320aic23_write cannot write 047 to register R6
tlv320aic23_write cannot write 004 to register R5
tlv320aic23_write cannot write 117 to register R0
tlv320aic23_write cannot write 117 to register R1
tlv320aic23_write cannot write 010 to register R4
tlv320aic23_write cannot write 070 to register R2
tlv320aic23_write cannot write 070 to register R3
tlv320aic23_write cannot write 001 to register R9
asoc: tlv320aic23-hifi <-> omap-mcbsp-dai.0 mapping ok
ALSA device list:
  #0: am3517evm
oprofile: hardware counters not available
oprofile: using timer interrupt.
TCP cubic registered
Initializing XFRM netlink socket
NET: Registered protocol family 17
NET: Registered protocol family 15
Registering the dns_resolver key type
VFP support v0.3: implementor 41 architecture 3 part 30 variant c rev 1
ThumbEE CPU extension supported.
Power Management for TI OMAP3.
clock: disabling unused clocks to save power
drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
omap_vout omap_vout: Buffer Size = 3686400
omap_vout omap_vout: : registered and initialized video device 1
omap_vout omap_vout: Buffer Size = 3686400
omap_vout omap_vout: : registered and initialized video device 2
Waiting 1sec before mounting root device...
Root-NFS: no NFS server address
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "mmcblk0p2" or unknown-block(2,0)
Please append a correct "root=" boot option; here are the available partitions:
1f00             512 mtdblock0  (driver?)
1f01            1792 mtdblock1  (driver?)
1f02             256 mtdblock2  (driver?)
1f03            5120 mtdblock3  (driver?)
1f04          254464 mtdblock4  (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
Backtrace:
[<c004c65c>] (dump_backtrace+0x0/0x110) from [<c04611c4>] (dump_stack+0x18/0x1c)
 r7:c05337b5 r6:00008000 r5:c06049a8 r4:c06049a8
[<c04611ac>] (dump_stack+0x0/0x1c) from [<c046122c>] (panic+0x64/0x180)
[<c04611c8>] (panic+0x0/0x180) from [<c0008f90>] (mount_block_root+0x1dc/0x21c)
 r3:00000000 r2:00000000 r1:cf01bf50 r0:c053385c
[<c0008db4>] (mount_block_root+0x0/0x21c) from [<c000907c>] (mount_root+0xac/0xcc)
[<c0008fd0>] (mount_root+0x0/0xcc) from [<c0009208>] (prepare_namespace+0x16c/0x1c4)
 r4:c06039a4
[<c000909c>] (prepare_namespace+0x0/0x1c4) from [<c00084bc>] (kernel_init+0x114/0x154)
 r5:c0030d54 r4:c0603940
[<c00083a8>] (kernel_init+0x0/0x154) from [<c0075a9c>] (do_exit+0x0/0x638)
 r5:c00083a8 r4:00000000

Try "rootwait" instead of "rootdelay=1" in your bootargs.

Hi wong,

I tried using rootwait instead of rootdelay.Now booting stops at "Waiting for root device /dev/mmcblk0p2".

I tried increasing the rootdelay to 10 so that it may find /dev/mmcblk0p2.But it is not.

Any other ideas?

Regards,

Hemanth Kumar RV

I would suggest to keep using rootwait. Your boot log does not show any mmc driver messages. Double check that you enabled the MMC driver in the kernel config.

Hi Wong,

I will check in config file.I was using pre-built images.

Since bootloader and uImage is getting executed from SD-Card  i believe MMC driver should be  enabled.

Regards,

Hemanth Kumar

Looks like that kernel has a MMC driver that does not print anything on boot. Other threads with that processor would suggest that 2.6.37 kernel for that processor might not support  MMC.

It can happen that u-boot supports MMC and Linux doesn't. U-boot doesn't check the card detect pin. If you card detect pin is disconnected or flaky, u-boot will succeed to read the MMC but linux will fail.

Hai Wong

If the MMC driver doesn't loads,then how it boots the uboot,uImage from mmcblk0p0????

The ROM Bootloader, u-boot and Linux do not use any common code. They have separate MMC drivers. The hardware signals Card Detect and Write Protect are usually just GPIOs. It is up to each driver to handle or not handle them. As far as I know, the RBL and u-boot drivers do not check the CD and WP pins. Their code just assumes that the card is there and it is writeable. The Linux does check the CD unless the kernel is configured otherwise.

Hi sekra,

If you build your own file system for omap board you need to edit file etc/fstab in your FS  as followed by below .For me i solved like this only now my board is working fine .

# stock fstab - you probably want to override this with a machine specific one

rootfs               /                    auto       defaults              1  1
proc                 /proc                proc       defaults              0  0
devpts               /dev/pts             devpts     mode=0620,gid=5       0  0
usbfs                /proc/bus/usb        usbfs      defaults              0  0
tmpfs                /var/volatile        tmpfs      defaults,size=16M     0  0
tmpfs                /dev/shm             tmpfs      mode=0777             0  0
tmpfs                /media/ram           tmpfs      defaults,size=16M     0  0

# uncomment this if your device has a SD/MMC/Transflash slot
#/dev/mmcblk0p1       /media/card          auto       defaults,sync,noauto  0  0