"Calgary: Unable to locate Rio Grande table in EBDA" <- what does this mean?

It seems that Calgary is a family of IOMMUs, used in most IBM X-Series (i.e. X86_64) blades and motherboards - as of 2008 (see here). The Rio Grande table was/is an information table within the Extended BIOS Data Area that tells the operating system where to find the Calgary IOMMU(s) (thanks @telcoM).

As you, OP, are not using such a machine, you might consider trying to disable the search for it in the kernel compilation parameters. As @jmullee reminds us, here are the relevant Linux kernel configuration parameters:

CONFIG_CALGARY_IOMMU=y
CONFIG_CALGARY_IOMMU_ENABLED_BY_DEFAULT=y

you would change these from y to n.