2008-06-17 03:31:52     Gunzip Error while Booting from Flash

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2008-06-17 03:31:52     Gunzip Error while Booting from Flash

Appalayagari Sreedhar (INDIA)

Message: 57363   




I am facing some problem while booting from Flash.


I have few questions regarding the CFG_BOOTM_LEN


uboot Readme documentation says:






"Normally compressed uImages are limited to an uncompressed size of 8 MBytes. If this is not enough,you can define CFG_BOOTM_LEN in your board config file to adjust this setting to your needs."




My uImage is of size 4.5MB (compressed gzip image). Flash Chip Size in my custom board is 8 MB. Sdram size is 64MB and Blackfin BMODE pins are connected to ground ( BMODE : 00).RootFS size is 16MB


when i define CFG_BOOTM_LEN to 0x4000000(64MB) in board config file. I got the CRC error while booting.


When i define CFG_BOOTM_LEN to 0x8000000(128MB) in board config file, CRC check is ok but i got the following gunzip error.


## Booting image at 20040000 ...

   Image Name:   uClinux Kernel and ext2

   Created:      2008-06-17   6:51:56 UTC

   Image Type:   Blackfin Linux Kernel Image (gzip compressed)

   Data Size:    4682014 Bytes =  4.5 MB

   Load Address: 00200000

   Entry Point:  00200000

addr = 1000000

len = 47711e

data = 1000040

   Verifying Checksum ... crc32 = 15df6767


   Uncompressing Kernel Image ... Error: inflate() returned -3

GUNZIP ERROR - must RESET board to recover


Is there any mathematical equation for finding the exact value for CFG_BOOTM_LEN with respect to the uImage.


" I believe i am doing something wrong/silly, I am new to linux, Please guide me in solving this problem, i have stuck with this for sometime".


Thanks and Best Regards,Sreedhar.




2008-06-17 19:19:53     Re: Gunzip Error while Booting from Flash

Mike Frysinger (UNITED STATES)

Message: 57433   


the bootm len really doesnt matter here.  the image already tells you the uncompressed size in the boot output:

Data Size:    4682014 Bytes =  4.5 MB


that means the U-Boot default of 8 meg is more than enough (and the Blackfin default of 64 is way more than enough)


something else is going wrong here


have you run any hardware validation tests to make sure your memory and your flash are stable ?  you should load the uimage into your external memory, run 'crc32' on it, write it to flash, and then run 'crc32' on it there.  then compare those crc values to running crc32 on your development host.




2008-06-18 03:33:34     Re: Gunzip Error while Booting from Flash

Appalayagari Sreedhar (INDIA)

Message: 57459   


Hi Mike,


Thankyou very much.


You could see that CRC32 is ok from my previous mail.


anyway i will check what you have suggested.


Thankyou very much.


Best Regards,Sreedhar.