Re: [U-Boot-Users] [PATCH v4] ppc: Add CFG_MEM_TOP_HIDE option to hide memory area that doesn't get "touched"

Dear Stefan,

in message 1206523009-18011-1-git-send-email-sr@denx.de you wrote:

It is strongly recommendet to not use the last 256 bytes on those

<nitpick> recommended </nitpick>

--- a/README +++ b/README @@ -1854,6 +1854,27 @@ Configuration Settings: Scratch address used by the alternate memory test You only need to set this if address zero isn't writeable

+- CFG_MEM_TOP_HIDE (PPC only):

• If CFG_MEM_TOP_HIDE is defined in the board config header,
  

• this specified memory area will get subtracted from the top
  

• (end) of ram and won't get "touched" at all by U-Boot. By
  

• fixing up gd->ram_size the Linux kernel should gets passed
  

• the now "corrected" memory size and won't touch it either.
  

• This should work for arch/ppc and arch/powerpc. Only Linux
  

• board ports in arch/powerpc with bootwrapper support, that
  

• recalculate the memory size from the SDRAM controller setup
  

• will have to get fixed.
  

• This option can be used as a workaround for the 440EPx/GRx
  

• CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
  

• be touched.
  

• WARNING: Please make sure that this value is a multiple of
  

• the Linux page size (normally 4k). If this is not the case,
  

• then the end address of the Linux memory will be located at a
  

• non page size aligned address and this could cause mayor
  

<nitpick> major </nitpick>

Will you send a pull request for the ppc4xx repo, or should I apply this directly?

Best regards,

Wolfgang Denk