From:   Michael Walle <michael@walle.cc>
To:     apeksha.gupta@nxp.com
Cc:     LnxRevLi@nxp.com, davem@davemloft.net, hemant.agrawal@nxp.com,
        kuba@kernel.org, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, nipun.gupta@nxp.com,
        qiangqing.zhang@nxp.com, sachin.saxena@nxp.com,
        Michael Walle <michael@walle.cc>
Subject: Re: [PATCH 0/5] drivers/net: add NXP FEC-UIO driver
Date:   Thu, 11 Nov 2021 12:06:42 +0100
Message-Id: <20211111110642.3340300-1-michael@walle.cc>
In-Reply-To: <20211110054838.27907-1-apeksha.gupta@nxp.com>
References: <20211110054838.27907-1-apeksha.gupta@nxp.com>
MIME-Version: 1.0
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[linux-devel@linux.nxdi.nxp.com doesn't exist in the public, which is quite
annoying when you reply to an email and the MTA doesn't accept it due to
invalid domains]

> This patch series introduce the fec-uio driver, supported for the inbuilt
> NIC found in the NXP i.MX 8M Mini SoC. Basic hardware initialization is
> performed in kernel via userspace input/output(UIO) to support FEC
> ethernet device detection in user space.

Could you elaborate for what this driver is needed? Doesn't the imx8mm
already have a network driver? What is the difference between them?

As a user, I couldn't find what this is all about, neither in this
commit message nor in the Kconfig help text.

> Userspace PMD uses standard UIO interface to access kernel for PHY
> initialisation and for mapping the allocated memory of register &
> buffer descriptor with DPDK which gives access to non-cacheable memory
> for buffer descriptor.
> 
> Module fec-uio.ko will get generated.
> imx8mm-evk-dpdk.dtb is required to support fec-uio driver.

-michael