RE: [PATCH 1/2] doc: announce region based device mapping support

["Xia, Chenbo" <chenbo.xia@intel.com>]

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Wednesday, July 13, 2022 3:18 PM
> To: Sunil Kumar Kori <skori@marvell.com>
> Cc: Ray Kinsella <mdr@ashroe.eu>; dev <dev@dpdk.org>; Xia, Chenbo
> <chenbo.xia@intel.com>; Thomas Monjalon <thomas@monjalon.net>
> Subject: Re: [PATCH 1/2] doc: announce region based device mapping support
> 
> On Tue, Jun 28, 2022 at 3:56 PM <skori@marvell.com> wrote:
> >
> > From: Sunil Kumar Kori <skori@marvell.com>
> >
> > Adding region based device mapping support, which enables pci device
> > to map only required memory region instead of mapping full BAR.
> >
> > Signed-off-by: Sunil Kumar Kori <skori@marvell.com>
> > ---
> >  doc/guides/rel_notes/deprecation.rst | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> >
> > diff --git a/doc/guides/rel_notes/deprecation.rst
> b/doc/guides/rel_notes/deprecation.rst
> > index 4e5b23c53d..8800a3eb41 100644
> > --- a/doc/guides/rel_notes/deprecation.rst
> > +++ b/doc/guides/rel_notes/deprecation.rst
> > @@ -125,3 +125,16 @@ Deprecation Notices
> >    applications should be updated to use the ``dmadev`` library instead,
> >    with the underlying HW-functionality being provided by the ``ioat``
> or
> >    ``idxd`` dma drivers
> > +
> > +* pci: Update ``rte_pci_device`` and ``rte_pci_driver`` to add region
> based
> > +  memory mapping support. There could be a requirement to mmap specific
> memory
> > +  region only. Using this mechanism, pci device can be mapped for
> > +  a given BAR at a given offset of given size.
> > +
> > +  ``rte_pci_device`` will be added with following field
> > +  ``regions[PCI_MAX_RESOURCE][PCI_MAX_REGION_PER_RESOURCE];``. This
> field will
> > +  specify the regions which are mapped for a given BAR.
> > +
> > +  ``rte_pci_driver`` will be added with ``rte_pci_region_map *regions``
> and
> > +  ``valid_bars[PCI_MAX_RESOURCE]``. Using these fields, driver can
> propagate
> > +  its region information which are required to be mmap.
> 
> I don't think we need a new deprecation notice for this.
> We still have Chenbo current notice:
> https://git.dpdk.org/dpdk/tree/doc/guides/rel_notes/deprecation.rst#n46
> 
> Besides, my proposal hides every bus specific device representations,
> and I think it covers your needs too.
> See https://patches.dpdk.org/project/dpdk/patch/20220710061736.973563-1-
> david.marchand@redhat.com/
> 
> Did I miss something?

Agree, I am about to say this :)

Sunil, with David's patchset, you can just send your patchset. David will help
clean-up the ABI for you.

Thanks,
Chenbo

> 
> 
> --
> David Marchand