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From: valerij zaporogeci <vlrzprgts@gmail.com>
Date: Thu, 22 Sep 2016 17:30:49 +0300
Message-ID: <CANPuzFxJhYPRv16o0Z1w0F0c22mvzo6sW6hGm43qEOZ4U8LRoQ@mail.gmail.com>
To: edk2-devel <edk2-devel@lists.01.org>
Subject: flat mapping vs identity mapping on ARM
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In the ARM architecture, there is such a thing - "flat mapping", where
MMU stage 1 is disabled and the mapping done is 1:1 and attributes set
to the predefined values.
Did I understand right, that this is NOT what UEFI means by "identity
mapping" with MMU enabled? And in the latter case there is need to
create all those page tables and stuff, setting 1:1 mapping between VA
and PA? If so, why to do that? Why "flat mapping" isn't what UEFI
would love to see as its mapping regime?