RE: [PATCH v4] uio: dfl: add HSSI subsystem feature id

[Zhang, Tianfei]

> -----Original Message-----
> From: Wu, Hao <hao.wu@xxxxxxxxx>
> Sent: Thursday, May 5, 2022 2:35 PM
> To: Zhang, Tianfei <tianfei.zhang@xxxxxxxxx>; trix@xxxxxxxxxx;
> mdf@xxxxxxxxxx; Xu, Yilun <yilun.xu@xxxxxxxxx>; linux-fpga@xxxxxxxxxxxxxxx;
> gregkh@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; Matthew Gerlach
> <matthew.gerlach@xxxxxxxxxxxxxxx>
> Subject: RE: [PATCH v4] uio: dfl: add HSSI subsystem feature id
> 
> > -----Original Message-----
> > From: Zhang, Tianfei <tianfei.zhang@xxxxxxxxx>
> > Sent: Thursday, May 5, 2022 8:16 AM
> > To: Wu, Hao <hao.wu@xxxxxxxxx>; trix@xxxxxxxxxx; mdf@xxxxxxxxxx; Xu,
> > Yilun <yilun.xu@xxxxxxxxx>; linux-fpga@xxxxxxxxxxxxxxx;
> > gregkh@xxxxxxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx; Matthew Gerlach
> > <matthew.gerlach@xxxxxxxxxxxxxxx>; Zhang, Tianfei
> > <tianfei.zhang@xxxxxxxxx>
> > Subject: [PATCH v4] uio: dfl: add HSSI subsystem feature id
> >
> > From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> >
> > Add the Device Feature List (DFL) feature id for the High Speed Serial
> > Interface (HSSI) Subsystem to the table of ids supported by the
> > uio_dfl driver.
> >
> > The HSSI Subsystem is a configurable set of IP blocks to be used as
> > part of a Ethernet or PCS/FEC/PMA pipeline.
> > Like the Ethernet group used by the N3000 card, the HSSI Subsystem
> > does not fully implement a network device from a Linux netdev
> > perspective and is controlled and monitored from user space software
> > via the uio interface.
> >
> > The Feature ID table of DFL can be found:
> > https://github.com/OPAE/dfl-feature-id
> 
> Is it possible to have multiple different HSSI implementations?
> Will they share the same feature id or not? If yes, why uses a generic name
> here?

The HSSI subsystem is a new design, there will use for a long time.

> 
> Is it possible someday this feature id is marked as legacy not used and introduce
> a new one as the same name?

No, this HSSI subsystem is a standard device which  was designed for OFS. 
It will extensively use for Intel FPGA PAC card in the feature.

> 
> >
> > Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
> > Acked-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> > Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> > Signed-off-by: Tianfei Zhang <tianfei.zhang@xxxxxxxxx>
> > ---
> > v4: add Reviewed-by and Acked-by tag and add Feature ID table url in
> > git message.
> > v3: change the name of this feature id to HSSI_SUBSYS and rewrite
> >     the git message.
> > v2: add HSSI introduction and the git repo of Feature ID table.
> > ---
> >  drivers/uio/uio_dfl.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/uio/uio_dfl.c b/drivers/uio/uio_dfl.c index
> > 89c0fc7b0cbc..8f39cc8bb034 100644
> > --- a/drivers/uio/uio_dfl.c
> > +++ b/drivers/uio/uio_dfl.c
> > @@ -45,9 +45,11 @@ static int uio_dfl_probe(struct dfl_device *ddev)
> > }
> >
> >  #define FME_FEATURE_ID_ETH_GROUP	0x10
> > +#define FME_FEATURE_ID_HSSI_SUBSYS	0x15
> >
> >  static const struct dfl_device_id uio_dfl_ids[] = {
> >  	{ FME_ID, FME_FEATURE_ID_ETH_GROUP },
> > +	{ FME_ID, FME_FEATURE_ID_HSSI_SUBSYS },
> >  	{ }
> >  };
> >  MODULE_DEVICE_TABLE(dfl, uio_dfl_ids);
> > --
> > 2.26.2