> -----Original Message----- > From: matthew.gerlach@xxxxxxxxxxxxxxx <matthew.gerlach@xxxxxxxxxxxxxxx> > Sent: Thursday, July 7, 2022 11:06 PM > To: Wu, Hao <hao.wu@xxxxxxxxx>; Xu, Yilun <yilun.xu@xxxxxxxxx>; Weight, > Russell H <russell.h.weight@xxxxxxxxx>; Muddebihal, Basheer Ahmed > <basheer.ahmed.muddebihal@xxxxxxxxx>; trix@xxxxxxxxxx; > mdf@xxxxxxxxxx; corbet@xxxxxxx; linux-fpga@xxxxxxxxxxxxxxx; linux- > doc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Zhang, Tianfei > <tianfei.zhang@xxxxxxxxx> > Cc: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx> > Subject: [PATCH v3 1/2] Documentation: fpga: dfl: add PCI Identification > documentation > > From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx> > > Add documentation on identifying FPGA based PCI cards prompted > by discussion on the linux-fpga@xxxxxxxxxxxxxxx mailing list. > > Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx> > --- > v3: Add url to page tracking PCI ID information for DFL based cards. > > v2: Introduced in v2. > --- > Documentation/fpga/dfl.rst | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/Documentation/fpga/dfl.rst b/Documentation/fpga/dfl.rst > index 15b670926084..5144775b860a 100644 > --- a/Documentation/fpga/dfl.rst > +++ b/Documentation/fpga/dfl.rst > @@ -507,6 +507,27 @@ ids application. > https://github.com/OPAE/dfl-feature-id > > > +PCI Device Identification > +================================ > +Since FPGA based PCI cards can be reconfigured to a perform a completely > +new function at runtime, properly identifying such cards and binding the > +correct driver can be challenging. In many use cases, deployed FPGA based > +PCI cards are essentially static and the PCI Product ID and Vendor ID pair > +is sufficient to identify the card. The DFL framework helps with the > +dynamic case of deployed FPGA cards changing at run time by providing > +more detailed information about card discoverable at runtime. > + > +At one level, the DFL on a PCI card describes the function of the card. > +However, the same DFL could be instantiated on different physical cards. > +Conversely, different DFLs could be instantiated on the same physical card. > +Practical management of a cloud containing a heterogeneous set of such > cards > +requires a PCI level of card identification. While the PCI Product ID and > +Vendor ID may be sufficient to bind the dfl-pci driver, it is expected > +that FPGA PCI cards would advertise suitable Subsystem ID and Subsystem > +Vendor ID values. Further PCI Product, Vendor, and Subsystem id tracking > +can be found at https://github.com/OPAE/dfl-feature-id/blob/main/dfl-pci- > ids.rst. I feel that we may not really need this in fpga-dfl doc, as this is not describing any new method provided by DFL, but just something from PCI standard, right? Thanks Hao
