From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [PATCH v3 2/4] net/mrvl: add mrvl net pmd driver
Date: Wed, 4 Oct 2017 01:24:27 +0100
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Cc: mw@semihalf.com, dima@marvell.com, nsamsono@marvell.com,
 Jianbo.liu@linaro.org, Jacek Siuda <jck@semihalf.com>
To: Tomasz Duszynski <tdu@semihalf.com>, dev@dpdk.org
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On 10/3/2017 12:51 PM, Tomasz Duszynski wrote:
> Add support for the Marvell PPv2 (Packet Processor v2) 1/10 Gbps adapter.
> Driver is based on external, publicly available, light-weight Marvell
> MUSDK library that provides access to network packet processor.
> 
> Driver comes with support for the following features:
> 
> * Speed capabilities
> * Link status
> * Queue start/stop
> * MTU update
> * Jumbo frame
> * Promiscuous mode
> * Allmulticast mode
> * Unicast MAC filter
> * Multicast MAC filter
> * RSS hash
> * VLAN filter
> * CRC offload
> * L3 checksum offload
> * L4 checksum offload
> * Packet type parsing
> * Basic stats
> * Stats per queue

I have more detailed comments but in high level,
what do you think splitting this patch into three patches:
- Skeleton
- Add Rx/Tx support
- Add features, like MTU update or Promiscuous etc.. support

> 
> Driver was engineered cooperatively by Semihalf and Marvell teams.
> 
> Semihalf:
> Jacek Siuda <jck@semihalf.com>
> Tomasz Duszynski <tdu@semihalf.com>
> 
> Marvell:
> Dmitri Epshtein <dima@marvell.com>
> Natalie Samsonov <nsamsono@marvell.com>
> 
> Signed-off-by: Jacek Siuda <jck@semihalf.com>
> Signed-off-by: Tomasz Duszynski <tdu@semihalf.com>

<...>

> +static struct rte_vdev_driver pmd_mrvl_drv = {
> +	.probe = rte_pmd_mrvl_probe,
> +	.remove = rte_pmd_mrvl_remove,
> +};
> +
> +RTE_PMD_REGISTER_VDEV(net_mrvl, pmd_mrvl_drv);

Please help me understand.

This driver implemented as virtual driver, because:
With the help of custom kernel modules, musdk library already provides
userspace datapath support. This PMD is an interface to musdk library.
Is this correct?

If so, just thinking loud:
- Why not implement this PMD directly on top of kernel interface,
removing musdk layer completely?
- How big problem that this PMD depends on custom kernel code?
- How library and custom kernel code delivered? For which platforms?

<....>