[U-Boot] uboot for MIPS: need help to skip relocate uboot and start uboot from RAM

[Pandurang Kale]

Hi Wolfgang Denk,

 Thanks for the response. Please find my questions inline.

On Thu, Mar 3, 2011 at 11:11 PM, Wolfgang Denk <wd at denx.de> wrote:

> Dear Pandurang Kale,
>
> In message <AANLkTikLJzuCSwOhMLz2sWy1j9a3LiV8zzY6=TjTfnrR at mail.gmail.com>
> you wrote:
> >
> > But when primary bootloader copies the uboot image to the RAM and passes
> the
> > control to the uboot, uboot (MIPS version of start.S and
> > arch/mips/lib/borad.c) tries to relocate the
> > already copied image from RAM (the primary bootloader copied it to start
> of
> > the RAM+1MB address) to top of the RAM (0x87fc0000) region thinking that
> the
> > uboot image is stored in flash.
>
> U-Boot does not "think" it is stored in flash - this is what you
> configured.  If you know you're always loading it to a fixed RAM
> address, you can use this as reference for TEXT_BASE instead

For MIPS I do not find the TEXT_BASE symbol, there is SYS_CFG_MONITOR_BASE
which it uses to relocate the code from the define symbol to high RAM
address. how can I avoid this?  As I see we have a switch defined for ARM,
CONFIG_SKIP_RELOCATE_UBOOT,  to skip the code relocation I cant find a
similar instance in MIPS code. Can you please throw some light on getting
the TEXT_BASE setting correctly for MIPS code? how can I do that?

> .
>
> > All I need to do is skip the uboot relocate code in MIPS version of uboot
>
> No, you do NOT want to do thjat, as it would cripple U-Boot and remove
> basic functionality from it.
>

> > I can see there is a switch for ARM processor,
> CONFIG_SKIP_RELOCATE_UBOOT,
>
> Are you looking at recent code and working boards?
>
I have recent uboot code for MIPS and I cant find any similar switch for
MIPS codebase. arch/mips/lib/board.c and arch/mips/cpu/start.S

>
> > I would really appreciate if you can guide me to overcome this issue to
> run
> > the uboot cleanly skipping the relocation.
>
> Do do not want to skip relocation.  U-Boot may need to auto-adjust
> it's start address dynamically, depending on configuration, system
> requirements and/or environment settings.
>
The uboot is already loaded in the RAM (by the primary boot loader) so I
dont want uboot to again relocate itself from one location of RAM to its
predefined high-memory region in RAM which I have explained in my first
mail.

>
> Best regards,
>
> Wolfgang Denk
>
> Thanks a lot,
Pandu

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