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From:   Lizhi Hou <lizhi.hou@xilinx.com>
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Subject: [PATCH V1 Create empty OF root 0/1] XRT Alveo driver infrastructure overview
Date:   Tue, 25 Jan 2022 21:48:06 -0800
Message-ID: <20220126054807.492651-1-lizhi.hou@xilinx.com>
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Hello,

Xilinx Alveo PCIe accelerator cards use flattened device tree to describe
HW subsystems or endpoints. Each device tree node represents a hardware
endpoint and each endpoint is an hardware unit which requires a driver.
The product detail: 
    https://www.xilinx.com/products/boards-and-kits/alveo.html

The feedback from the previous patches was to create a base tree if there
is not one and apply the unflattened device nodes by existing Linux
platform device and OF infrastructure. Please refer to previous discussion
with device tree and fpga maintainers.
    https://lore.kernel.org/lkml/CAL_JsqJfyRymB=VxLuQqLpep+Q1Eie48dobv9sC5OizDz0d2DQ@mail.gmail.com/
    https://lore.kernel.org/lkml/20220105225013.1567871-1-lizhi.hou@xilinx.com/

This patch adds OF_EMPTY_ROOT config. When it is selected and there is not
a device tree, create an empty device tree root node.

Lizhi Hou (1):
  of: create empty of root

 drivers/of/Kconfig         |  3 +++
 drivers/of/Makefile        |  1 +
 drivers/of/of_empty_root.c | 51 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+)
 create mode 100644 drivers/of/of_empty_root.c

-- 
2.27.0