[U-Boot-Users] Running U-boot in cache area.

[Jerry Van Baren]

sathesh babu wrote:
> Hi,
>   I am tring to run U-boot on MIPS 24KE processor.
>     I have done MIPS 24KE cache initilization and configured it for 
> write through  mode in the start.S file.
>  
> If I specify SDRAM start address  as uncached area ( start 
> with 0xa0000000), u-boot boots up and able to get the u-boot prompt.
>  
> It I try SDRAM start address as cached area ( Start with 0x80000000), 
> the u-boot comes up to relocation function and hangs.
>  
> Could you please tell me what could be the problem.
> Did i mss any thing?.
>  
> I see the same behaviour with write back mode also.
>  
> Should i call any cache invalidation ( doing this as part of cache 
> initilization in the start.S) or flush functions before calling 
> relocation().
>  
> I am  enabling primary cache only and no secondary cache.
>  
> Thanks in advance.
>  
> Regards.
> Sathesh

This may be the FAQ.  Enabling caches typically enables bursting and 
disabling caches typically disables bursting (I'm not familiar with your 
MIPS - YMMV).  This class of RAM problems tend to show up only when 
bursting.
<http://www.denx.de/wiki/view/DULG/UBootCrashAfterRelocation>

gvb