RE: Driver: PCIe: 'pci_map_sg' returning invalid bus address?

[Yuhong Bao <yuhongbao_386@hotmail.com>]

> > - add swiotlb support to x86_32 (I don't think that it's difficult but
> > I might miss something).
>
> I think the highmem support might be a bit tricky. The PowerPC folks
> did some work in there, so it _ought_ to work.
>
> Evan, you could edit arch/x86/Kconfig and change:
> config SWIOTLB
> def_bool y if X86_64
>
> to say
> def_bool y if X86
>
> and see how it works? FYI, it might wreak havoc on your machine thought,
> so be sure you have a fail-safe kernel and backup your root/home
> directory.
>
> (FYI, I made Xen-SWIOTLB be capable of running under X86_32 and so far
> no trouble.. but that is not baremetal obviously).
In fact, if you are going to port swiotlb, why not port the entire iommu support to x86_32 with PAE too?
In fact, I am really irritated at how the x86-64 port was developed completely separate from mainline, when 
it is just a variant of the same x86 arch. For another example of this, look at the history of ACPI SRAT support
in Linux.

Yuhong Bao