[U-Boot] [PATCH v4] Marvell Kirkwood family SOC support

[Wolfgang Denk]

Dear Prafulla Wadaskar,

In message <73173D32E9439E4ABB5151606C3E19E201CD5CF545 at SC-VEXCH1.marvell.com> you wrote:
>  
> In case of kirkwood specially in some board version if we use Kirkwood without internal BootROM we need to configure DRAM before setting stack in DRAM, this should be done in lowlevel_init.S i.e. lowlevel_init or arch_lowlevel_init jump

This may be what many ARM systems are currently doing, but actually it
is not what I'd like to see.

Normally DRAM should only be initialized right before relocation to
RAM, i. e. relatively late in the boot sequence, and definitely by C
code (at a time, when you have printf() and friends for debugging).

Also, normally the actual RAM size should be auto-detected using  the
utilities  provided  by  common/memsize.c,  etc.  [Also,  flash sizes
should be auto-detected.]

If you don't have any on-chip memory on your  system,  or  any  other
SRAM  etc.  that  could  be  used for initial data or stack, then the
standard method is to lock (parts of) D-Cache and use this as RAM.


It would be great if such standard procedures would find their way
into U-Boot on ARM, too.


[Note that I wrote "I'd like to see", and "normally", and "should". I
did not say "must" - I'm a realist, and I know that ARM still  has  a
long way to go to fully recover from the ARMBoot heritage.]

Thanks in advance.

Best regards,

Wolfgang Denk

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