LinuxHangsAfterUncompressingKernel < DULG

%SECTION0{name=LinuxHangsAfterUncompressingKernel}% Linux hangs after uncompressing the kernel

   Question:: I am using U-Boot with a Linux kernel version
    =Y= (=Y= &lt; 2.4.5-pre5), but the last message I see is
    <verbatim>                                                                    
Uncompressing Kernel Image ... OK
    </verbatim>
    Then the system hangs.

   Answer:: Most probably you pass bad parameters to the Linux kernel.
    <br>                                                                                
    There are several possible reasons:
      * Bad device tree; for example, check that the memory map set up by the
        boot loader (like mapping of IMMR, PCI addresses etc.) is consistent
   with what is encoded in your device tree specification.

Here some possible reasons for older Linux kernel versions:

   Linux:: arch/ppc:
      * arch/ppc: Bad definition of the =bd_info= structure
       %BR%
       You must make sure that your machine specific header file
       (for instance _include/asm-ppc/tqm8xx.h_)
       includes the same definition of the Board Information
       structure as we define in
       _include/ppcboot.h_, and make sure that
       your definition of =IMAP_ADDR= uses the same
       value as your U-Boot configuration in
       =CFG_IMMR=.
      * Bad clock information
       %BR%                                                                     
       Before kernel version 2.4.5-pre5 (!BitKeeper Patch 1.1.1.6,
       22MAY2001) the kernel expected the clock information in MHz,
       but recent kernels expect it in Hz instead. U-Boot passes
       the clock information in Hz by default.
       To switch to the old behaviour, you can set the
       environment variable ="clocks_in_mhz"= in U-Boot:
       <pre>                                                                         
%UBOOT_PROMPT% setenv clocks_in_mhz 1
%UBOOT_PROMPT% saveenv
       </pre>
       For recent kernel the ="clocks_in_mhz"= variable *must not be set*.
       If it is present in your environment, you can delete it as follows:
       <pre>                                                                         
%UBOOT_PROMPT% setenv clocks_in_mhz
%UBOOT_PROMPT% saveenv
       </pre>
       %X% A common error is to try ="setenv clocks_in_mhz 0"= or to some other value - this
       will not work,
       as *the value of the variable is not important at all*.
       It is the *existence* of the variable that will be checked.
      * Inconsistent memory map
       %BR%
       Some boards may need corrct mappings for some special hardware devices like
       BCSR (Board Control and Status Registers) etc.
       Verify that the mappings expected by Linux match those created by U-Boot.
14.2.20. My standalone program does not work		1. Abstract		14.2.22. How can I implement automatic software updates?
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