[coreboot-gerrit] Change in coreboot[master]: soc/intel/graphics: Create Kconfig for shifting graphic memory base

[Ethan Tsao (Code Review)]

Attention is currently required from: Subrata Banik, Nico Huber, Ravishankar Sarawadi, Tim Wawrzynczak, Paul Menzel, Raj Astekar, Patrick Rudolph.
Ethan Tsao has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/61389 )

Change subject: soc/intel/graphics: Create Kconfig for shifting graphic memory base
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Patch Set 11:

(1 comment)

Patchset:

PS11:
> How does one know what the GFX_MEMBASE_OFFSET is for a given intel GFX generation?

For given Intel Gfx generation, graphic memory base shall be extracted from 0x18 directly, so GFX_MEMBASE_OFFSET is zero.

This patch is for future platform(LMEMBAR).