Re: standardize device identification

[Finn Christensen <fc@napatech.com>]

    -----Original Message-----
    From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas
    Monjalon
    Sent: 20. december 2017 23:03
    To: dev@dpdk.org
    Cc: Yuanhan Liu <yliu@fridaylinux.org>; Adrien Mazarguil
    <adrien.mazarguil@6wind.com>; Ciara Loftus <ciara.loftus@intel.com>;
    Kevin Traynor <ktraynor@redhat.com>; stephen@networkplumber.org;
    ferruh.yigit@intel.com
    Subject: Re: [dpdk-dev] standardize device identification
    
    Changing the title and adding more comments inline:
    
    19/12/2017 00:05, Thomas Monjalon:
    > Let's summarize and resume this thread.
    >
    > We need a generic syntax to describe a device.
    > This syntax can be used
    > 	- before initializing the device (i.e. whitelist/blacklist)
    > 	- or after the initialization (e.g. user config)
    >
    > We need to answer 4 questions:
    > 1/ what are the separators (comma, colon, etc)?
    > 2/ how to distinguish a device identification from a configuration?
    > 3/ what are the mandatory parts?
    > 4/ what can be the optional properties?
    >
    > 30/11/2017 08:35, Yuanhan Liu:
    > > What this patch proposes is to use "name[,mac]" syntax. "name" is
    > > the PCI id for pci device. For vdev, it's the vdev name given by
    > > user. The reason "mac" is needed is for some devices (say
    > > ConnectX-3), 2 ports (in a single NIC) have the same PCI id.
    >
    > Based on the feedbacks we had, I suggest a syntax where everything is
    > optional key/value pairs, and split in 3 categories:
    > 	- bus (pci, vdev, vmbus, fslmc, etc)
    > 	- class (eth, crypto)
    > 	- driver (i40e, mlx5, virtio, etc)
    
    The key/value pair describing the category scope is mandatory and must
    be the first pair in the category properties.
    Example: bus=pci, must be placed before id=0000:01:00.0
    
    > Between categories, the separator is a slash.
    > Inside a category, the separator is a comma.
    > Inside a key/value pair, the separator is an equal sign.
    >
    > It may look like this:
    >
    bus=BUS_NAME,id=BUS_ID/class=CLASS_NAME,dev_port=PORT_NUM,m
    ac=MAC_ADDR
    > ESS/driver=DRIVER_NAME,driverspecificproperty=VALUE
    >
    > A device is identified when every properties are matched.
    > Before device is probed, only the bus category is relevant.
    > For the simple PCI whitelist, it means moving from
    > 	-w 0000:01:00.0
    > to
    > 	-w bus=pci,id=0000:01:00.0
    >
    > It is possible to mix some settings in these devargs syntax if the
    > keys are differents. Example: mac= is for identification by MAC,
    > whereas newmac= would be for specifying a MAC address to set.
    >
    > Agreement?
    
 
We also need to distinguish between multiple ports sitting on same PCI bus ID.
and from our point of view, this will fully cover our needs.
Thanks - great proposal.

Regards,
Finn Christensen, Napatech


    Yuanhan is proposing to use this syntax in OVS option dpdk-devargs:
    https://mail.openvswitch.org/pipermail/ovs-dev/2017-
    December/342273.html
    
    Please, any feedback or approval that this syntax is good?