Re: mn10300 linker script update

[Duane Ellis <duane at duaneellis dot com>]

>> Arguably at least some of these scripts could be integrated into 
ld's scheme for building scripts
>> from the basic ELF templates since they usually just vary in a few 
addresses and the GROUP
>> statements.  But I'm not sure I want to try and tackle that yet.

Yes, I know this is more of an "ld" comment - but... anyway...

I sure would like to know about "ld's scheme for building scripts" - 
where can I find that type of info.

I've never found it in any of the LD docs, info or man pages.

Maybe things have changed more recently.

Why do I ask: I live in an 'embedded world'.

I've had to deal with problems like these:

For example - in some consumer electronic stuff I did we had:

Deep Sleep
   Some I have some code that lives in "on chip sram" and is safe 
during 'power off' (deep battery sleep) we killed power to the SDRAM and 
then rescaned the ELF when I kill power to the SDRAM chip - I reload it 
when power is restored. or you "cache line lock" data into your 16K on 
chip I and D cache during sleep.

Shallow Sleep
   Set the sdram in 'mobile-sdram-backup-mode' and go to sleep only a 
portion of the sdram is maintained. The rest suffers bit rot and fades away.

The Deep & Shallow sleep are some what easy
   You arrange your ELF file correctly - then your ELF loader has 2 modes.
   (1) load everything, or (2) skip the parts that are in the "good" area.

In micro controllers -
  there are some chunks of code that must be "ram-functions" - commonly 
flash reprogramming code
  Or something that must run with 0 wait states.

In specialized DSPs -
  Like blackfin that has (fast) L1 ram, and (slower) L2 ram, and off 
chip (more slower) SDRAM, and other off chip (utterly slow) NOR flash 
and so on.
  Even more weird - the dual core stuff.

I have had no end of fun with LD scripts - and I still find them 
confusing.  They are often "non-trivial"

And yes, I would like to know about "ld's scheme for building scripts".

-Duane.