generic CAN/CAN FD susbsytem for RTEMS - status, review and mainlining

[Pavel Pisa]

Hello Emanuel,

On Sunday 23 of June 2024 17:15:13 emanuel stiebler wrote:
> On 2024-06-21 06:27, Pavel Pisa wrote:
> > I want to inform you about the progress of the project.
> >
> > The CTU local project project links can be found in the
> > section CAN/CAN FD Subsystem and Drivers for RTEMS on our page
> >
> >   
> > https://canbus.pages.fel.cvut.cz/#cancan-fd-subsystem-and-drivers-for-rte
> >ms
> >
> > The merge request draft for review is available at RTEMS GitLab
> >
> >    https://gitlab.rtems.org/rtems/rtos/rtems/-/merge_requests/49
> >
> > and we collect feedback and are preparing enhancements based
> > on fedback, i.e. to resolve Gedare noticed problem around
> > RTEMS_CAN_CHIP_STOP IOCTL.
>
> I would actually like to try it. I have some Xilinx MPSoC boards here,
> and need some CAN FD (FD is important here).
>
> But, somehow I can't manage to find the schematics & layouts in KiCAD on
> the web? Am I just clicking the wrong buttons?
>
> I think I found the VHDL sources ...

The VHDL sources of the CTU CAN FD are available from
repository

  https://gitlab.fel.cvut.cz/canbus/ctucanfd_ip_core

the integration into Xilinx Zynq project can be found at

  https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top

There are are more branches, the last CTU CAN FD by Ondrej Ille
for our MZ_APO board at branch "mz_apo-2x-xcan-4x-ctu-v25",
older/MIT licensed version at branch "mz_apo-2x-xcan-4x-ctu"
and build for CAN benchmark board at "can-bench-2x-xcan-4x-ctu".

The MZ_APO board schematics and mechanic are available
in the source form at

   https://gitlab.com/pikron/projects/mz_apo/microzed_apo

Schematics are in Peter Porazil's PEDA schematic/PCB
deign system. But PDF output can be fount for example there

  https://cmp.felk.cvut.cz/~pisa/apo/mz_apo/

The CAN bench board for CAN latency tester is result of Martin
Jerabek's bachelor theses and CTU CAN FD integration has been
done as part of his master's theses. Locate them in the list
at https://gitlab.fel.cvut.cz/otrees/org/-/wikis/theses-defend
Actual files

  
https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top/wikis/uploads/56b4d27d8f81ae390fc98bdce803398f/F3-BP-2016-Jerabek-Martin-Jerabek-thesis-2016.pdf
  https://dspace.cvut.cz/bitstream/handle/10467/80366/F3-DP-2019-Jerabek-Martin-Jerabek-thesis-2019-canfd.pdf

KiCAD design there

  https://gitlab.fel.cvut.cz/canbus/zynq/canbech-hw

PDF export
  
https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top/-/wikis/uploads/93b79611ed12cfb806fcefc6f86973fc/F3-BP-2016-Jerabek-Martin-priloha-CAN-BENCH_Schematics_RevA.pdf

But generally, the connection can be really simple, you have CTU CAN FD
Vivado component which as APB and CAN Rx and Tx pins and you need
to connect CAN/CAN FD transceiver to these, i.e. MCP2562FD
or some other. We usually add CAN cross-bar between
FPGA CAN Tx/Rx pins and controllers Tx and Rx signals

  https://gitlab.fel.cvut.cz/canbus/zynq/zynq-can-sja1000-top/-/tree/master/system/ip/can_crossbar_2.0

which allows mutual testing and interconnection of multiple
controllers to single physical links without need of external
jumpers.

We have used the design with Zynq 7000 series boards
abut even that I have been asked and organized purchase
of Xilinx UlraScale systems for the former group, my
communication with group after their move to other CTU
institute has been disrupted by their actions so we have
not checked design with UlraScale. But I expect that there
should be no problems. We have tested Altera/Intel SoC
and FPGA PCIe cards integration as well as some other
FPGAs and technologies and even some other universities
report use on some experimental silicon tapeouts.

Best wishes,

                Pavel

                Pavel Pisa
    phone:      +420 603531357
    e-mail:     pisa at cmp.felk.cvut.cz
    Department of Control Engineering FEE CVUT
    Karlovo namesti 13, 121 35, Prague 2
    university: http://control.fel.cvut.cz/
    personal:   http://cmp.felk.cvut.cz/~pisa
    social:     https://social.kernel.org/ppisa
    projects:   https://www.openhub.net/accounts/ppisa
    CAN related:http://canbus.pages.fel.cvut.cz/
    RISC-V education: https://comparch.edu.cvut.cz/
    Open Technologies Research Education and Exchange Services
    https://gitlab.fel.cvut.cz/otrees/org/-/wikis/home