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Groups > linux.kernel > #1689433
| From | Alan Tull <atull@kernel.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview |
| Date | 2017-07-17 22:20 +0200 |
| Message-ID | <u4kEN-1f3-5@gated-at.bofh.it> (permalink) |
| References | <tWrtL-4is-3@gated-at.bofh.it> <tWrtM-4is-9@gated-at.bofh.it> <u2rho-17U-9@gated-at.bofh.it> <u2E4V-Uj-5@gated-at.bofh.it> <u3iF4-28N-1@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Fri, Jul 14, 2017 at 6:59 PM, Luebbers, Enno <enno.luebbers@intel.com> wrote: > On Thu, Jul 13, 2017 at 12:25:20PM +0800, Wu Hao wrote: >> On Wed, Jul 12, 2017 at 09:51:32AM -0500, Alan Tull wrote: >> > On Sun, Jun 25, 2017 at 8:51 PM, Wu Hao <hao.wu@intel.com> wrote: >> > >> > Hi Hao, >> > >> > > Add a document for Intel FPGA driver overview. >> > > >> > > Signed-off-by: Enno Luebbers <enno.luebbers@intel.com> >> > > Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> >> > > Signed-off-by: Wu Hao <hao.wu@intel.com> >> > > ---- >> > > v2: added FME fpga-mgr/bridge/region platform driver to driver organization. >> > > updated open discussion per current implementation. >> > > fixed some typos. >> > > --- >> > > Documentation/fpga/intel-fpga.txt | 256 ++++++++++++++++++++++++++++++++++++++ >> > > 1 file changed, 256 insertions(+) >> > > create mode 100644 Documentation/fpga/intel-fpga.txt >> > > >> > > diff --git a/Documentation/fpga/intel-fpga.txt b/Documentation/fpga/intel-fpga.txt >> > > new file mode 100644 >> > > index 0000000..4a29470 >> > > --- /dev/null >> > > +++ b/Documentation/fpga/intel-fpga.txt >> > > @@ -0,0 +1,256 @@ >> > > +=============================================================================== >> > > + Intel FPGA driver Overview >> > > +------------------------------------------------------------------------------- >> > > + Enno Luebbers <enno.luebbers@intel.com> >> > > + Xiao Guangrong <guangrong.xiao@linux.intel.com> >> > > + Wu Hao <hao.wu@intel.com> >> > > + >> > > +The Intel FPGA driver provides interfaces for userspace applications to >> > > +configure, enumerate, open, and access FPGA accelerators on platforms equipped >> > > +with Intel(R) FPGA PCIe based solutions and enables system level management >> > > +functions such as FPGA reconfiguration, power management, and virtualization. >> > > + >> > > +HW Architecture >> > > +=============== >> > > +From the OS's point of view, the FPGA hardware appears as a regular PCIe device. >> > > +The FPGA device memory is organized using a predefined data structure (Device >> > > +Feature List). Features supported by the particular FPGA device are exposed >> > > +through these data structures, as illustrated below: >> > > + >> > > + +-------------------------------+ +-------------+ >> > > + | PF | | VF | >> > > + +-------------------------------+ +-------------+ >> > > + ^ ^ ^ ^ >> > > + | | | | >> > > ++-----|------------|---------|--------------|-------+ >> > > +| | | | | | >> > > +| +-----+ +-------+ +-------+ +-------+ | >> > > +| | FME | | Port0 | | Port1 | | Port2 | | >> > > +| +-----+ +-------+ +-------+ +-------+ | >> > > +| ^ ^ ^ | >> > > +| | | | | >> > > +| +-------+ +------+ +-------+ | >> > > +| | AFU | | AFU | | AFU | | >> > > +| +-------+ +------+ +-------+ | >> > > +| | >> > > +| FPGA PCIe Device | >> > > ++---------------------------------------------------+ >> > > + >> > > +The driver supports PCIe SR-IOV to create virtual functions (VFs) which can be >> > > +used to assign individual accelerators to virtual machines. >> > > + >> > > +FME (FPGA Management Engine) >> > > +============================ >> > > +The FPGA Management Engine performs power and thermal management, error >> > > +reporting, reconfiguration, performance reporting, and other infrastructure >> > > +functions. Each FPGA has one FME, which is always accessed through the physical >> > > +function (PF). >> > > + >> > > +User-space applications can acquire exclusive access to the FME using open(), >> > > +and release it using close(). >> > > + >> > > +The following functions are exposed through ioctls: >> > > + >> > > + Get driver API version (FPGA_GET_API_VERSION) >> > > + Check for extensions (FPGA_CHECK_EXTENSION) >> > > + Assign port to PF (FPGA_FME_PORT_ASSIGN) >> > > + Release port from PF (FPGA_FME_PORT_RELEASE) >> > > + Program bitstream (FPGA_FME_PORT_PR) >> > > + >> > >> > I was hoping the API mailing list might have an opinion about this, >> > but I think adding ioctls to the kernel is discouraged. Could these >> > be sysfs? >> >> Hi Alan, >> >> As you see below, we have defined a lot of sysfs interface for device >> info, attributes and simple control operations. But for some actions >> which requires complex inputs/outputs parameters (e.g a struct with >> multiple items) with userspace, ioctls are used. I feel in such cases, >> ioctls seem more suitable than sysfs. >> > > Also, we're thinking that some operations require that you first "acquire > ownership" of the respective device, which I believe maps more easily to > open() and ioctls than sysfs. > > Thanks > - Enno Yes, sysfs doesn't implement open/close so there's no clean way to have one thing in userspace that owns the interface. It's a shame. Alan
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Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview Alan Tull <atull@kernel.org> - 2017-07-12 17:00 +0200
Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview Wu Hao <hao.wu@intel.com> - 2017-07-13 06:40 +0200
Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview "Luebbers, Enno" <enno.luebbers@intel.com> - 2017-07-15 02:00 +0200
Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview Alan Tull <atull@kernel.org> - 2017-07-17 22:20 +0200
Re: [PATCH v2 01/22] docs: fpga: add a document for Intel FPGA driver overview Greg KH <greg@kroah.com> - 2017-07-18 07:30 +0200
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