2008-02-14 16:48:43     Moving uCLinux

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2008-02-14 16:48:43     Moving uCLinux

mijagi mijagi (CROATIA)

Message: 51071    Hello.

 

I'm running 2.4 kernel on BF535.

I know that it's obsolete piece of hardware, but I hope you can help.

 

Initially, my system had this memory map:

-------

 

    The u-boot-1.1.1 memory map is as below,

   

    +----------------------------+ 0x00000000

    |                            |   

    |                            |    Reserved 

    +----------------------------+ 0x000001000

    |                            |   

    |                            |    u-boot application

    |                            |   

    |                            |   

    +----------------------------+ 0x00040000

    |                            |    Environment variables and dynamic memory allocation

    +----------------------------+ 0x00064000

    |                            |   

    |                            |

    |                            |

    |                            |    uClinux loading and running

    |                            |

    |                            |    

    +----------------------------+  0x00800000

    |                            |    uClinux image

    |                            |   

    +----------------------------+ 0x01000000

 

 

This was set up using SDRAM bank0 which has 16MB.

Everything (uboot & uclinux) was working OK.

 

 

Now I've added more SDRAM banks (they work fine - checked out), and memory space has increased.

I need to move my entire system to location 0x2000000 (uboot & uclinux).

Basically I want this:

 

   

    +----------------------------+ 0x00000000

    |                            |   

    |                            |    Reserved 

    +----------------------------+ 0x002001000

    |                            |   

    |                            |    u-boot application

    |                            |   

    |                            |   

    +----------------------------+ 0x02040000

    |                            |    Environment variables and dynamic memory allocation

    +----------------------------+ 0x02064000

    |                            |   

    |                            |

    |                            |

    |                            |    uClinux loading and running

    |                            |

    |                            |    

    +----------------------------+  0x02800000

    |                            |    uClinux image

    |                            |   

    +----------------------------+ 0x03000000

 

 

I've managed to move my u-boot to this higher memory area.

U-boot is working fine at 0x2001000. Of course, u-boot configures  SDRAM control registers and sets up all new SDRAM banks.

 

BUT... uCLinux doesn't work.

I've set up the ram.ld file (moved uCLinux space to these higher locations).

 

So what happens when I boot?

u-boot extracts image (to 0x2064000) and does everything what it should.

Then message "Booting uCLinux..." appears.

And then - NOTHING.

Not a thing.

 

My biggest question is, could it be that uCLinux reverts state of SDRAM control registers to an old state, with only bank0 activated, deactivating higher banks (which now contain uCLinux itself)???

Is it that the reason why booting stalls?

 

Is there any file (which executes immediately on kernel boot) where uCLInux itself writes to SDRAM control registers (and overwrites values set up by the uboot?)?

 

OR I forgot to change some other setting?

 

I repeat, uclinux was working fine when all addresses were 0x2000000 lower.

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2008-02-14 16:56:10     Re: Moving uCLinux

Mike Frysinger (UNITED STATES)

Message: 51073    unfortunately, no, we cannot help

 

we never supported a 2.4 kernel and we do not have any BF535 systems to test on, so the 2.6 kernel will not work

 

you'll have to get support from whoever you got the source code from

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