The calgary IOMMU was only used on high-end IBM systems in the early
x86_64 age. This is an unlikely OpenWrt target and in fact upstream
are looking to drop the driver entirely with the bonus that we no
longer see:
[ 0.000000] Calgary: detecting Calgary via BIOS EBDA area
[ 0.000000] Calgary: Unable to locate Rio Grande table in EBDA - bailing!
Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
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