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Subject: Re: [PATCH V1 Create empty OF root 0/1] XRT Alveo driver
 infrastructure overview
To:     Lizhi Hou <lizhi.hou@xilinx.com>, <devicetree@vger.kernel.org>,
        <robh@kernel.org>
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References: <20220126054807.492651-1-lizhi.hou@xilinx.com>
From:   Lizhi Hou <lizhi.hou@xilinx.com>
Message-ID: <17d60142-c72f-1a11-45de-e9a2974abeb8@xilinx.com>
Date:   Mon, 31 Jan 2022 16:49:53 -0800
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Hi Rob,


We are still waiting for your feedback and guidance on this. Could you 
take a look?


Thanks,

Lizhi

On 1/25/22 9:48 PM, Lizhi Hou wrote:
> 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
>