Talk:Board:asus/f2a85-m

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Linux complains about prefetchable memory regions: http://www.coreboot.org/pipermail/coreboot/2012-December/073133.html

[    0.648901] pci 0000:00:02.0: no compatible bridge window for [mem 0xb0000000-0xbfffffff 64bit pref]
[    0.658001] pci 0000:00:15.1: no compatible bridge window for [mem 0xc0000000-0xc00fffff 64bit pref]
[    0.667124] pci 0000:01:00.0: no compatible bridge window for [mem 0xb0000000-0xbfffffff 64bit pref]
[    0.676229] pci 0000:04:00.0: no compatible bridge window for [mem 0xc0004000-0xc0004fff 64bit pref]
[    0.685332] pci 0000:04:00.0: no compatible bridge window for [mem 0xc0000000-0xc0003fff 64bit pref]

In drivers/pci/setup-res.c pci_claim_resource() this message means these PCI devices claim those memory regions but the PCI-PCI bridge between the device and the CPU – maybe just the host bridge – are not set large enough to include that memory.

That it mentions prefetchable memory is kind of minor: it's an address that requires 64-bit decoding, and it's an address that can be prefetched, but that's just the way the PCI device BAR is set.

TODO: put a PCI device list here

I think the fix is to either set up the PCI-PCI bridges so the memory can be accessed, or remap the PCI device so the memory is within what the bridge will forward.