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From: Evgeny Yakovlev <insoreiges@gmail.com>
Date: Tue, 16 May 2017 15:55:55 +0300
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To: edk2-devel@lists.01.org
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Subject: How to look up ACPI device node from DXE driver
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I am writing a DXE driver for a paravirtualized HyperV storage device for
OvmfPkg. Host hypervisor exposes the presence of this device through ACPI
device node in DSDT. Specific AML path itself may be different from host to
host but device UID is always a string: "VMBus".

I was hoping to be able to walk DSDT table in my DXE driver to locate this
device node and start publishing necessary protocols, but I am having
trouble figuring out how to do this, i.e. are there any support libraries
or protocols to traverse ACPI tables or how do I have to do that manually.
Will be glad for any advice, thanks.