[coreboot-gerrit] [XS] Change in coreboot[master]: drivers/intel/gma/Kconfig: Add VBT compression configuration entry

[Jérémy Compostella (Code Review)]

Attention is currently required from: Anil Kumar K, Arthur Heymans, Subrata Banik.

Jérémy Compostella has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/76816?usp=email )

Change subject: drivers/intel/gma/Kconfig: Add VBT compression configuration entry
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Patch Set 8:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/76816/comment/f11d373f_bf456652 :
PS7, Line 14: For instance, it can be set to `none' to allow the VBT binary to be
            : used in pre-memory stages such as romstage.
> Why is that necessary? Compression does work pre-memory. […]

I could not get it to work on x86 (cf. code below).

Listing. src/lib/cbfs.c
    448  } else if (!cbfs_cache.size) {
    449  	/* In order to use the cbfs_cache you need to add a CBFS_CACHE to your
    450  	 * memlayout. For stages that don't have .data sections (x86 pre-RAM),
    451  	 * it is not possible to add a CBFS_CACHE. */
    452  	ERROR("Cannot map compressed file %s without cbfs_cache\n", mdata->h.filename);
    453  	return NULL;
    454  } else {

File src/drivers/intel/gma/Kconfig:

https://review.coreboot.org/c/coreboot/+/76816/comment/e86c1299_5a3537fe :
PS7, Line 69:
> No input validation on the string? coreboot only has 2 supported compression mechanisms. […]

To my knowledge coreboot supports `none`, `lzma` and `lz4` so it cannot be a boolean.