From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ramon Fried <rfried.dev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Memory aliasing and nodes
Date: Thu, 21 Apr 2022 13:33:10 +0300
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To: devicetree-spec-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

Hi all,
This is the second time in my career that I've stumbled upon a SOC
which has 32bit memory aliasing for high memory for the usage of
drivers that can only address 32bit address space.

Basically, a subset of a memory higher than 4GB can be accessed also
through a range in the low 4GB addresses.

I didn't see any support for this neither Linux kernel nor in device
tree. I'm wondering if you considered adding a way to describe such
addressing in the device tree, and maybe later Linux can add support
for it.

Thanks,
Ramon