Gedare, Thank you for your input on this. I'm still digesting LinCAN, but it looks like a good way to go. On our end, we will likely have some resources to throw at this in a few weeks.
-Phil On Thu, Aug 17, 2023 at 4:26 PM Gedare Bloom <ged...@rtems.org> wrote: > Hi Phil, > > On Wed, Aug 9, 2023 at 6:38 AM Philip Kirkpatrick > <p.kirkpatr...@reflexaerospace.com> wrote: > > > > Hello, > > > > Some people on our team here at Reflex are preparing to implement some > CAN drivers. Specifically for TMS570 and for ZynqMP-RPU (side note my > latest patch for that on Jun 29th is still sitting there unreviewed). I > was wondering what the current status of the CAN API is. > Feel free to ping the patch. At the moment, this email based system is > all we have, and sometimes patches may not get a lot of attention > especially if no one "owns" it -- such as new BSPs. > > > I saw in August of last year and API was added and then last month was > reverted with this patch: > > https://lists.rtems.org/pipermail/devel/2023-July/076013.html > > The comment on the patch says the API isn't mature enough for release. > What deficiencies need to be resolved in the API, is this being actively > worked on, and should we design against this API or is there a different > API we should target? > > > The implementation of that API was deficient. It did not support > multiple read/write transactions, it had a custom-built ring buffer > that was not fully vetted, and some other problems related to > threads+priorities. I expect to have some time to look at how to > provide better CAN support inside of RTEMS. This has been an ongoing > discussion I've been having with Pavel Pisa and others for many years > now (a decade?). The direction that I will prefer to go is to port > LinCAN > https://cmp.felk.cvut.cz/~pisa/can/doc/lincandoc-0.3.5.pdf > > Both Pavel and I are interested in seeing this come through. So far, > we mostly do it on volunteer time or as side pieces of other work. > Pavel's group has good experience with CAN and CAN FD, and with both > TMS570 and the Zynq (non-MP) boards, with Linux, RTEMS, and NuttX. We > would be open to collaborating, subject to whatever time or resource > constraints everyone has :) Michal Lenc has been working on this topic > as a thesis, "CAN FD Support for Space Grade Real-Time RTEMS > Executive" > > Regarding LinCAN itself, there is one design challenge to port it, > which has to do with the use of internal FIFOs already in LinCAN code > base, or to use RTEMS/POSIX message queue style to interface the CAN > drivers and userspace. I actually see there are good reasons to > support both ways, and may explore exactly that. We have had quite > some discussions here on the topic: > * https://lists.rtems.org/pipermail/devel/2023-March/074537.html > * https://lists.rtems.org/pipermail/devel/2022-April/071235.html > * https://lists.rtems.org/pipermail/devel/2013-April/030761.html (for > historical good measure) > > Gedare > > > Thank you, > > Phil > > _______________________________________________ > > devel mailing list > > devel@rtems.org > > http://lists.rtems.org/mailman/listinfo/devel >
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