On Mon, Feb 01, 2021 at 08:59:06PM +0800, Wu, Hao wrote: > > Subject: [PATCH v10 2/2] Documentation: fpga: dfl: Add description for DFL UIO > > support > > > > This patch adds description for UIO support for dfl devices on DFL > > bus. > > > > Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx> > > Reviewed-by: Tom Rix <trix@xxxxxxxxxx> > > --- > > v2: no doc in v1, add it for v2. > > v3: some documentation fixes. > > v4: documentation change since the driver matching is changed. > > v5: no change. > > v6: improve the title of the userspace driver support section. > > some word improvement. > > v7: rebased to next-20210119 > > v8: some doc fixes. > > v9: some doc change since we switch to the driver in drivers/uio. > > v10: no change. > > --- > > Documentation/fpga/dfl.rst | 23 +++++++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > > > diff --git a/Documentation/fpga/dfl.rst b/Documentation/fpga/dfl.rst > > index c41ac76..e35cf87 100644 > > --- a/Documentation/fpga/dfl.rst > > +++ b/Documentation/fpga/dfl.rst > > @@ -7,6 +7,7 @@ Authors: > > - Enno Luebbers <enno.luebbers@xxxxxxxxx> > > - Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx> > > - Wu Hao <hao.wu@xxxxxxxxx> > > +- Xu Yilun <yilun.xu@xxxxxxxxx> > > > > The Device Feature List (DFL) FPGA framework (and drivers according to > > this framework) hides the very details of low layer hardwares and provides > > @@ -530,6 +531,28 @@ Being able to specify more than one DFL per BAR has > > been considered, but it > > was determined the use case did not provide value. Specifying a single DFL > > per BAR simplifies the implementation and allows for extra error checking. > > > > + > > +Userspace driver support for DFL devices > > +======================================== > > +The purpose of an FPGA is to be reprogrammed with newly developed > > hardware > > +components. New hardware can instantiate a new private feature in the DFL, > > and > > +then present a DFL device in the system. In some cases users may need a > > +userspace driver for the DFL device: > > + > > +* Users may need to run some diagnostic test for their hardware. > > +* Users may prototype the kernel driver in user space. > > +* Some hardware is designed for specific purposes and does not fit into one of > > + the standard kernel subsystems. > > + > > +This requires direct access to MMIO space and interrupt handling from > > +userspace. The uio_dfl module exposes the UIO device interfaces for this > > +purpose. > > Current uio_dfl doesn't have interrupt handling support, right? I guess we need > to make sure no confusion on the description here. other place looks good to me. Will fix it. Thanks, Yilun
