[SeaBIOS] [PATCH] x86: fix read{b, w, l} and write{b, w, l} functions

[Kevin O'Connor]

On Tue, Feb 17, 2015 at 02:00:49PM -0800, Ameya Palande wrote:
> Use barrier() for memory mapped IO functions.
> 
> This fixes pvscsi driver to boot on QEMU's pvscsi controller.
> Test command:
> qemu -m 512 --enable-kvm -device pvscsi,id=pvscsi0
> -device scsi-disk,bus=pvscsi0.0,drive=drive0
> -drive id=drive0,if=none,file=ubuntu1410.img,if=none
> -bios seabios/out/bios.bin

Thanks.  I didn't think it was standard for a barrier to be present in
these functions, but I now see that Linux also uses barrier here.  So,
I've committed your patch (with a couple of minor changes).

Thanks, also, for tracking down the PVSCSI problem.

-Kevin