Hi coreboot fellows,
after two years with the new resource allocator it's time again for some changes[1]. Much less invasive than last time, but again there will be changes in the pattern where resources are placed. So once more this may uncover bugs in case fixed resources are not reserved properly.
Reasons for the changes are somewhat the same as always: we haven't finished the support for 64-bit resources. Currently one has to opt in for a placement above 4G with a resource flag, and even this has its limitations. For instance, reserved space for hot-pluggable de- vices can be placed above 4G with a Kconfig setting, but there's no rule what should happen with the resources of cold-plugged devices. In the worst case, allocation for those can fail.
Another reason are approaching changes to support multiple PCI host bridges and multiple resource windows per domain.
I digress... So everybody is invited to test the patch train. There is a new Kconfig option RESOURCE_ALLOCATION_TOP_DOWN. The default y should work fine, though in case of regressions it would be nice to have it tested with both settings.
Cheers, Nico
[1] https://review.coreboot.org/q/topic:allocator+status:open