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Date: Mon, 30 Aug 2021 12:23:50 +0200
From: "Gerd Hoffmann" <kraxel@redhat.com>
To: devel@edk2.groups.io
Subject: mmio mappings for runtime service
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  Hi,

What is the correct way to make sure runtime services can access
mmio registers, i.e. that there is a mapping in the page tables
for the mmio page needed?

Is that the job of the firmware?
Or should the OS calling the runtime service handle that?
In case of the latter: How does the OS figure which pages are needed?

thanks,
  Gerd