Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/33738 )
Change subject: device/Kconfig: Add HAVE_EXT_GFX kconfig ......................................................................
Patch Set 3:
(1 comment)
Patch Set 3:
(1 comment)
I do not see the usefulness of having that as a build time option.
Its always been build time option through Kconfig either HAVE_FSP_GOP or VGA_RUN_ROM. do you have some example where both been selected and platform can dynamically pick GFX over off board card and bring display.
Also, why can’t the payload like SeaBIOS run the Option ROM?
I'm not sure if i can give answer. My effort here to make offboard card work with one intel RVP platform
https://review.coreboot.org/#/c/33738/3/src/device/Kconfig File src/device/Kconfig:
https://review.coreboot.org/#/c/33738/3/src/device/Kconfig@129 PS3, Line 129: select FRAMEBUFFER_SET_VESA_MODE
Why?
i don't understand what you mean by "Why" ? Coreboot policies are been designed to either enable GOP/VBT or option rom statically. I'm only looking at IA platform, where i could see FSP GOP is default enable through Kconfig from mainboard and FSP GOP is only responsible of initialize IGD and it doesn't bother to initialize and look for off board GFX card unless user unselect FSP GOP and selects VGA_ROM_RUN which is parallel to FSP GOP. Hence you could only support one way display over other