[S] Change in flashrom[main]: Provide an option to use PCI_ACCESS_ECAM to access pci register

[Peter Marheine (Code Review)]

Attention is currently required from: Hsuan Ting Chen, Hsuan-ting Chen, Kane Chen.

Peter Marheine has posted comments on this change by Kane Chen. ( https://review.coreboot.org/c/flashrom/+/83896?usp=email )

Change subject: Provide an option to use PCI_ACCESS_ECAM to access pci register
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Patch Set 3:

(1 comment)

File meson_options.txt:

https://review.coreboot.org/c/flashrom/+/83896/comment/e7d5df65_be4f737e?usp... :
PS3, Line 9: option('use_libpci_ecam', type : 'boolean', value : false)
It looks like this is only used for 100-series PCHs which presumably always support ECAM, so is this option needed?

It seems like if we can assume ECAM is always available on the relevant systems and it's less prone to bugs caused by libpci interacting poorly with OS-level drivers accessing the same hardware, then we should use ECAM as long as it's supported by the version of libpci in use and don't need this option.