Hi Thomas, > -----Original Message----- > From: Thomas Monjalon <tho...@monjalon.net> > 08/11/2022 00:52, Chautru, Nicolas: > > Hi Thomas, > > Reminder : do you mind kindly clarifying/confirming below. Then we can > update the docs accordingly. Thanks. > > > > From: Chautru, Nicolas > > > From: Thomas Monjalon <tho...@monjalon.net> > > > > 31/10/2022 16:43, Chautru, Nicolas: > > > > > From: Thomas Monjalon <tho...@monjalon.net> > > > > > > 12/10/2022 19:59, Nicolas Chautru: > > > > > > > +Bind PF UIO driver(s) > > > > > > > +~~~~~~~~~~~~~~~~~~~~~ > > > > > > > + > > > > > > > +Install the DPDK igb_uio driver, bind it with the PF PCI > > > > > > > +device ID and use ``lspci`` to confirm the PF device is > > > > > > > +under use by ``igb_uio`` DPDK > > > > > > UIO driver. > > > > > > > > > > > > igb_uio is not recommended. > > > > > > Please focus on VFIO first. > > > > > > > > > > > > > +The igb_uio driver may be bound to the PF PCI device using > > > > > > > +one of two methods for ACC200: > > > > > > > + > > > > > > > + > > > > > > > +1. PCI functions (physical or virtual, depending on the use > > > > > > > +case) can be bound to the UIO driver by repeating this > > > > > > > +command for every > > > > function. > > > > > > > + > > > > > > > +.. code-block:: console > > > > > > > + > > > > > > > + cd <dpdk-top-level-directory> insmod > > > > > > > + ./build/kmod/igb_uio.ko echo "8086 57c0" > > > > > > > > + /sys/bus/pci/drivers/igb_uio/new_id > > > > > > > + lspci -vd8086:57c0 > > > > > > > + > > > > > > > + > > > > > > > +2. Another way to bind PF with DPDK UIO driver is by using > > > > > > > +the ``dpdk-devbind.py`` tool > > > > > > > + > > > > > > > +.. code-block:: console > > > > > > > + > > > > > > > + cd <dpdk-top-level-directory> > > > > > > > + ./usertools/dpdk-devbind.py -b igb_uio 0000:f7:00.0 > > > > > > > + > > > > > > > +where the PCI device ID (example: 0000:f7:00.0) is obtained > > > > > > > +using lspci -vd8086:57c0 > > > > > > > > > > > > This binding is not specific to the driver. > > > > > > It would be better to refer to the Linux guide instead of > > > > > > duplicating it again and again. > > > > > > > > > > > > > +In a similar way the PF may be bound with vfio-pci as any PCIe > device. > > > > > > > > > > > > You could mention igb_uio here. > > > > > > Is there any advantage in using igb_uio? > > > > > > > > > > > > > > > > Igb_uio is arguably easier to use to new user tend to start with > > > > > it or specific > > > > ecosystem. This is typically the entry point (no iommu, no flr > > > > below the bonnet, no vfio token...) hence good to have a bit of > > > > handholding with a couple of lines capturing how to easily run a > > > > few tests. I don't believe this is too redundant to have these few > > > > lines compared to the help in bring to the user not having to double > > > > guess > their steps. > > > > > More generally there are a number of module drivers combinations > > > > > that are > > > > supported based on different deployments. We don't document in too > > > > much details for the details since that is not too ACC specific > > > > and there is more documentation no pf_bb_config repo for using the > > > > PMD from > > > the VF.. > > > > > > > > > > Basically Thomas let us know more explicitly what you are > > > > > suggesting as > > > > documentation update. You just want more emphasis on vfio-pci flow > > > > (which is fair, some of it documented on pf_bb_config including > > > > the vfio token passing but we can reproduce here as well) or something > else? > > > > > > > > There are 2 things to change: > > > > 1/ igb_uio is going to be deprecated, so we must emphasize on VFIO > > > > > > Is there a date for deprecation? Do you mean to EOL the dpdk-kmods > > > repository itself; or something more specific for DPDK code like > > > removing RTE_PCI_KDRV_IGB_UIO; or last to just take out from > documentation? > > There is no final decision yet, but the techboard wishes we focus more on VFIO > which is in Linux upstream. > Out-of-tree module (like igb_uio) is not recommended. > > > > It tends to be historical but uio has value notably for ease of use. > > I don't think it is easy to use an out-of-tree module. > It needs to be compiled and installed.
That is more up to the user. For some users/ecosystems it can be genuinely significantly easier and also historical deployments still to be supported. Even if vfio-pci is the focus for most deployments. But mentioning that since you are thinking about removing support, I see value keeping support for a bit still > > > > 2/ for doc > > > > maintenance, it is better to have common steps described in one place. > > > > If needed, you can change the common doc and refer to it. > > > > > > Do you mean to remove these sections and just add a pointer to > > > https://doc.dpdk.org/guides/linux_gsg/linux_drivers.html instead in > > > all these bbdev PMDS? > > Yes > If the Linux guide is not convenient, I suggest to improve it. > > > > Please kindly confirm. I see specific steps for binding in many > > > other PMDs docs in DPDK, a bit redundant but provides simple steps > > > specific to a PMD in one place. I don't mind either way. > > The other PMD docs should point to a common doc. > > Redundant docs make very hard to update. > OK, did an update on this v1 for your review https://patches.dpdk.org/project/dpdk/patch/20221108234325.45589-2-nicolas.chau...@intel.com/ the warning from checkpatch is a false alarm Thanks Nic
