[coreboot-gerrit] Change in coreboot[master]: lib/cbfs: Add HAVE_CBFS_CACHE Kconfig

[Raul Rangel (Code Review)]

Attention is currently required from: Furquan Shaikh, Julius Werner, Karthik Ramasubramanian.
Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56577 )

Change subject: lib/cbfs: Add HAVE_CBFS_CACHE Kconfig
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Patch Set 3:

(1 comment)

Patchset:

PS3:
> I think this makes sense. […]

When I add the CBFS_CACHE() entry to the memlayout, ramstage reports the correct value:

```
coreboot-4.14-2248-ga3f9b16e0549-dirty Thu Oct 14 16:53:49 UTC 2021 ramstage starting (log level: 8)...
RX: main: cbfs_cache->size: 8192
```

What is the behavior when linking with an external that doesn't exist?

__weak extern u8 _##name##_size[];

If I never add the CBFS_CACHE() region to the memlaytout, that symbol is undefined right? Shouldn't it cause a linker error? Or is it expecting the module loader to take care of updating the pointer?