[U-Boot] [PATCH 0/2] [RFC] DEBUG: relocate to fixed address

[Wolfgang Denk]

Dear Tetsuyuki Kobayashi,

In message <1353476660-18018-1-git-send-email-koba at kmckk.co.jp> you wrote:
> 
> U-Boot from NOR flash relocates itself to RAM erea. The relocation address is
> calaculated at runtime to get maxium contiguous space to load kernel. So it may
> vary after code changed. In the early debug phase it would be easier to handle
> if the relocation address does not change per build.

No, it is not.  You still need to determine where it gets relocated to,
and iot makes no difference for debugging wehter you enter one number
or another one.

Any debugger out there today allows you to automatemost such
operations by scripts or functions or macros you can define to help
you doing that.

> My idea is define fixed address as CONFIG_DEBUG_RELOC_FIX_ADDR in config file
> and relocate to the address. Then you don't need to execute 'bdinfo' command to
> get actual relocated address. It is done by the first patch.

I'm not willing to accept such change.  It appears to ad a (minimal)
easement at first glance, but at the same time it bears potential to
break a large number of other things, and not unlikely in areas which
are why you need to run a debugger in the first place.

This makes no sense.

> The second patch is for u-boot_r, which is linked for fixed relocation address.
> When you want to symbolic debug after relocation, flash 'u-boot.bin' and
> load symbol from 'u-boot_r' to debugger.
> (CF. When you want to symblic debug before relocation, load symbol from 'u-boot'
>  to debugger.)

Why would that be needed?  The standard ELF file has all debug
information you ever may need.

Just to save the "load symbol table" command?   Again, this is not
worth the effort on one side, and likely to break things in other
places.

Best regards,

Wolfgang Denk

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