Some PCI peripherals, such as discrete VGA adapters, require a great
amount of memory mapped IO. This patch allows the user to select at
build time the bottom IO to leave enough space for such devices.
We cannot calculate this value at runtime because it has to be set
before the PCI devices are enumerated. 0x80000000 has been successfully
boot-tested on A88XM-E (fam15tn), G505S (fam15tn) and AM1I-A (fam16kb).
Signed-off-by: Mike Banon <mikebdp2@gmail.com>
Change-Id: Ie235631231bcb4aeebaff2e0026da2ea9d82f9d0
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38472
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michał Żygowski <michal.zygowski@3mdeb.com>
e7f176cd61