On 10/5/2021 6:24 AM, Apeksha Gupta wrote:
-----Original Message-----
From: Ferruh Yigit <ferruh.yi...@intel.com>
Sent: Friday, October 1, 2021 8:15 PM
To: Apeksha Gupta <apeksha.gu...@nxp.com>;
david.march...@redhat.com; andrew.rybche...@oktetlabs.ru
Cc: dev@dpdk.org; Sachin Saxena <sachin.sax...@nxp.com>; Hemant
Agrawal <hemant.agra...@nxp.com>
Subject: Re: [EXT] Re: [dpdk-dev] [PATCH v3 1/5] net/enetfec: introduce NXP
ENETFEC driver
Caution: EXT Email
On 10/1/2021 11:22 AM, Apeksha Gupta wrote:
-----Original Message-----
From: Ferruh Yigit <ferruh.yi...@intel.com>
Sent: Thursday, September 23, 2021 3:40 PM
To: Apeksha Gupta <apeksha.gu...@nxp.com>;
david.march...@redhat.com; andrew.rybche...@oktetlabs.ru;
ferruh.yi...@intel.com
Cc: dev@dpdk.org; Sachin Saxena <sachin.sax...@nxp.com>; Hemant
Agrawal <hemant.agra...@nxp.com>
Subject: [EXT] Re: [dpdk-dev] [PATCH v3 1/5] net/enetfec: introduce NXP
ENETFEC driver
Caution: EXT Email
On 9/9/2021 9:43 PM, Apeksha Gupta wrote:
ENETFEC (Fast Ethernet Controller) is a network poll mode driver
for NXP SoC i.MX 8M Mini.
Hi Apeksha,
Before going into details, I have some high level comments to start with,
please
find comments below.
This patch adds skeleton for enetfec driver with probe function.
Signed-off-by: Sachin Saxena <sachin.sax...@nxp.com>
Signed-off-by: Apeksha Gupta <apeksha.gu...@nxp.com>
<...>
+++ b/doc/guides/nics/enetfec.rst
@@ -0,0 +1,122 @@
+.. SPDX-License-Identifier: BSD-3-Clause
+ Copyright 2021 NXP
+
+ENETFEC Poll Mode Driver
+========================
+
+The ENETFEC NIC PMD (**librte_net_enetfec**) provides poll mode
driver
+support for the inbuilt NIC found in the ** NXP i.MX 8M Mini** SoC.
+
+More information can be found at NXP Official Website
+<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fw
ww.nxp.com%2Fproducts%2Fprocessors-and-microcontrollers%2Farm-
processors%2Fi-mx-applications-processors%2Fi-mx-8-processors%2Fi-
mx-
8m-mini-arm-cortex-a53-cortex-m4-audio-voice-
video%3Ai.MX8MMINI&data=04%7C01%7Capeksha.gupta%40nxp.com
%7C74fdc59c47574d828f7608d97e7a4df3%7C686ea1d3bc2b4c6fa92cd99c5
c30
1635%7C0%7C1%7C637679886024819097%7CUnknown%7CTWFpbGZsb3d8ey
JWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%
7C3000&sdata=TjuqIfC8yXwBa3DLCgA7djItfV0UmZ6lA3uLDQ7TFwY%3D
&reserved=0>
+
+ENETFEC
+-------
+
+This section provides an overview of the NXP ENETFEC and how it is
+integrated into the DPDK.
+
+Contents summary
+
+- ENETFEC overview
+- ENETFEC features
+- Supported ENETFEC SoCs
+- Prerequisites
+- Driver compilation and testing
+- Limitations
+
+ENETFEC Overview
+~~~~~~~~~~~~~~~~
+The i.MX 8M Mini Media Applications Processor is built to achieve both
high
+performance and low power consumption. ENETFEC is a hardware
programmable
+packet forwarding engine to provide high performance Ethernet
interface.
It has 1Gbps interface, right? It can be good to give more details on the
Ethernet interface.
[Apeksha] Okay.
+The diagram below shows a system level overview of ENETFEC:
+
+
====================================================+=====
==========
+ US +-----------------------------------------+ | Kernel Space
+ | | |
+ | ENETFEC Driver | |
+ +-----------------------------------------+ |
+ ^ | |
+ ENETFEC RXQ | | TXQ |
+ PMD | | |
+ | v | +----------+
+ +-------------+ | | fec-uio |
+ | net_enetfec | | +----------+
+ +-------------+ |
+ ^ | |
+ TXQ | | RXQ |
+ | | |
+ | v |
+
===================================================+======
=========
+ +----------------------------------------+
+ | | HW
+ | i.MX 8M MINI EVK |
+ | +-----+ |
+ | | MAC | |
+ +---------------+-----+------------------+
+ | PHY |
+ +-----+
+
+ENETFEC Ethernet driver is traditional DPDK PMD driver running in the
userspace.
+The MAC and PHY are the hardware blocks. 'fec-uio' is the UIO driver,
ENETFEC PMD
+uses UIO interface to interact with kernel for PHY initialisation and for
mapping
+the allocated memory of register & BD in kernel with DPDK which gives
access to
+non-cacheable memory for BD.
Why a specific uio driver, 'fec-uio', is required? I think this is the major
issue to clarify to proceed.
In DPDK we have full framework to support uio, to do the all memory
mapping,
interrupt configuration etc..., common to all drivers.
But in this case driver is implemented as virtual driver and it handles its
own
uoi handling itself. Why the driver can't use existing support and
implemented
as physical driver?
[Apeksha] Yes you are correct. As per our knowledge, UIO framework is
there for VM & PCI bus devices and not for vdev bus devices.
That is part of the comment, why driver implemented as vdev instead of
physical
device?
What is the actual device bus?
[Apeksha] Actual bus is 'platform' bus which is not supported in DPDK.
In that case, should each bus other than the PCI bus have UIO framework in
their driver?
Can't we find a way to extend the uio support in the common code?
