[coreboot-gerrit] Change in coreboot[master]: src/Kconfig: increase heap size if using flattened image tree

[Arthur Heymans (Code Review)]

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32392 )

Change subject: src/Kconfig: increase heap size if using flattened image tree
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Patch Set 3:
> Patch Set 3:
> > Patch Set 3:
> >
> > 1M is really a lot and wouldn't fit in most ramstages. Is that much heap really needed or should the linker scripts be adapted?
>
> I'm confused by the "wouldn't fit" comment. Can you please explain under what conditions something won't fit?

If the heap is too large the ramstage can exceed the allotted size, resulting in an assertion error during the linking ("Ramstage exceeded its allotted size! (sz)" in memlayout.h). A lot of arm SOC have < 1M allotted for ramstage which prevents FDT support without increasing it or specifying a smaller heap size.