Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/libgfxinit/+/27154 )
Change subject: gma pipe setup: Fix secondary pipe cursors <= Sandy Bridge ......................................................................
Patch Set 3:
(1 comment)
https://review.coreboot.org/#/c/27154/3/common/hw-gfx-gma.ads File common/hw-gfx-gma.ads:
https://review.coreboot.org/#/c/27154/3/common/hw-gfx-gma.ads@141 PS3, Line 141: "Reading of Config_State depends on the platform configuration.");
Just to be sure: And this configuration is only known at runtime right?
Yes. In cases where GMA.Config_State is actually read, it is runtime information. If it is read, depends on the compile-time configuration.
This is actually a side effect of the dynamic CPU detection. A build for the Sandy Bridge "Generation" that supports both Sandy and Ivy processors with different registers would have to read this runtime information to decide which set of registers to use. For builds for other generations or builds that only support either Sandy or Ivy, this would be static information, hence the annotation.