On Monday, 30 September 2019 23:53:36 UTC+2, ce...@tuta.io wrote: > > There is a kernel module driver - src/rtapi/shmdrv folder and shmdrv.h and > shmdrv.c specifically - which I understand was initially meant for RTAI > support (maybe) but then as everything moved into userspace it was phased > out. But given this use-case, it wouldn't be too hard to dust it off and > use it for kernel-space connection with AXI DMA driver. Looking at the > https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18842337/DMA+Drivers+-+Soft+IPs > > < > https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18842337/DMA+Drivers+-+Soft+IPs> > > page from Xilinx and the Linux port at > https://github.com/Xilinx/linux-xlnx/tree/master/drivers/dma/xilinx < > https://github.com/Xilinx/linux-xlnx/tree/master/drivers/dma/xilinx> it > should be possible to connect the HAL memory with DMA driver. > > seems highly probable
> My initial idea to synchronize (or have one) memory is probably not that > great. Linux side Hal memory and FPGA side HAL memory would be better off > synchronized only on pins (data) which transcend the barrier. (HAL > component which runs in Linux RT thread with pin connected to HAL component > in FPGA fabric.) That way the number of signal changes from fast FPGA side > to "slow" ARM side would be minimal. In the fpga some sort of state machine(s) logic would be implemented to act like a (small os)(protocol governing the rules for behaviour and triggering dma communication. > > > However, would it be possible to use some of these premade AXI DMA IP > cores for this idea? Yes > Given it is Open-Source and probably should encompass both Intel and > Xilinx? > Oh I wouldn't worry right now about being Intel compatible it seems like Altera is destined to survive Intel(who has brought no visible innovation to the sub $500 socfpga market in their time), right now Xilinx is holding the lead (the soft spot), so let's focus on what we currently have available to play with.... > > Cern. > > > Michael B. > > Sep 27, 2019, 23:03 by ce...@tuta.io <javascript:>: > > > Been doing some (extremely light) reading into AXI/CHI and besides > discovering that it will need many 180° world-view changes before even > basic understanding sets in it looks like the possibility of memory > access/sharing is real. Differently than I thought but still good enough. > > > > Comes to mind how much of needed work is already done by vendor and > community and how much it would need to be done (programmed) by Machinekit? > > > > Also took high altitude look into C/C++ HLS and discovered that it looks > like something even I could do. That's cool. > > > > Cern. > > > > > > Sep 26, 2019, 23:04 by mib.ho...@gmail.com <javascript:>: > > > >> > >> > >> On Thursday, 26 September 2019 21:19:04 UTC+2, ce...@tuta.io wrote: > >> > >>> Sep 26, 2019, 17:53 by >> mib.ho...@gmail.com <>>> : > >>> > >>> > I'm probably the wrong guy to answer this question as I'm a noob > into how sw os's work, but regarding linux memory access from the fpga: > >>> > > >>> Thanks. Sorry for probably idiotic questions, I am noob about FPGA > development. > >>> > >>> > >> > >> Ok :-) > >> > >> > >>> > > >>> > A (hw) function in fpga (also with dma channels), can address any > linux memory location (even sw restricted ones). > >>> > > >>> > If needed it is also possible to setup say like a 64KB dual port > shared memory block inside the fpga fabric and have both fpga and linux > access to that. > >>> > > >>> Are both solutions useful for this scenario? I imagine that the > frequency of change will be lot higher on FPGA side than on Linux side. For > example the encoder counter will be updated almost constantly. > >>> > >>> Cern. > >>> > >>> > >> > >> Well on the fpga side you don't have any cpu-like structure that > governs every thing, > >> only clock signals, and flags > >> and every function you implement runs on it's own simultaneously (in > parallel) (think 1 sw core for every function) > >> on every clock cycle. > >> > >> > >> > >>> > > >>> > > >>> > On Thursday, 26 September 2019 15:48:35 UTC+2, >> ce...@tuta.io > <>>> wrote: > >>> > > >>> >> Sep 26, 2019, 01:29 by >> >> mib.ho...@gmail.com <>>> <>>> : > >>> >> > >>> >> > Well current state is that PR (Partial Reconfiguration) is brand > new to the OS (Open Source) world, > >>> >> > as > IntelfPGA (former Altera) "just" have promised it for their > 19.1 release (no lite version out yet), <>> >> https://github.com/ < > https://github.com/>>> >> machinekit/mksocfpga/issues/>> 100 <>> > https://github.com/>> machinekit/mksocfpga/issues/>> 100 < > https://github.com/machinekit/mksocfpga/issues/100>>> >>> > > >>> >> > on the contrary Xilinx have sneaked it out very quietly with > their Vivado 2019.1 release this summer <>> >> https://github.com/ < > https://github.com/>>> >> machinekit/mksocfpga/issues/>> 100 <>> > https://github.com/>> machinekit/mksocfpga/issues/>> 100 < > https://github.com/machinekit/mksocfpga/issues/100>>> >>> > > >>> >> > > >>> >> > So while the idea has had time to settle in this old thread, the > possibility of implementation here in Machinekit is brand new.... :-) > >>> >> > Michael B > >>> >> > > >>> >> Well, > >>> >> and how it is with the memory? And with the bus connection between > hard ARM processor and FPGA fabric? Because now we have the HAL memory > block locked into RAM with HAL library enabled allocating and memory > (alignment) management from Linux side. But I presume that for FPGA-side > components, that would not be good enough and this memory block will have > to be directly in FPGA fabric so the components can use this space as a > "register", right? Will then be possible to atimically access this memory > (or variables there stored) both from Linux running on an ARM core and > component in FPGA fabric? (I mean as a direct memory access, zero-copy, not > some memory synchronization.) > >>> >> > >>> >> Cern. > >>> >> > >>> >> > > >>> >> > On Wednesday, 25 September 2019 20:49:04 UTC+2, >> >> > ce...@tuta.io <>>> <>>> wrote: > >>> >> > > >>> >> >> I am late to the party, I know, sorry, but this idea is very > interesting to me. As I know that perspectives and opinions change, I would > like to inquire about the current state. If all in this thread is still > valid or if it was redacted in some way? > >>> >> >> > >>> >> >> I need to wrap my head around this concept, but fundamentally > speaking, I see no reason why it should not be possible and even how it is > that much different from the current state. Because, currently the > operation on HAL is discrete and sequential. But only up to the point. As I > see it, the basic structure of HAL is the input and output of each block > (component). What is happening inside the component is a black box and of > no particular interest to the user or a system. That "happening" is enabled > by so called threads or tasks (on the Linux OS side), but actually from > theoretical point of view are also of no importance. > >>> >> >> > >>> >> >> Given the dawn of multicore, we can have multiple threads > running independent on each other on different isolated CPU/cores all > reaching the same memory. There is still the limit that threads on one > instance has to be run in increments of the first one, but I am not sure if > that is real limit or just something nobody changed from LinuxCNC days. > (Because really, it is nonsense.) > >>> >> >> > >>> >> >> If you can somehow pass-through the memory (I/O) from FPGA-side > HAL to Linux-side HAL, I think you are pretty much done and you have HAL in > FPGA. (HostMot2 FPGA firmware is also a HAL type, but you have the ugly > read/write functions. I call it the LinuxCNC way of thinking about it.) > >>> >> >> > >>> >> >> Because then it will be the same old, same old. > >>> >> >> > >>> >> >> And that opens up some very interesting possibilities. > >>> >> >> > >>> >> >> BTW, I have only very rough understanding about FPGA > development. But that SystemC looks extremely promising. > >>> >> >> > >>> >> >> Cern. > >>> >> >> > >>> >> > > >>> >> > > >>> >> > > >>> >> > -- > >>> >> > website: > >> >> http://www.machinekit.io < > http://www.machinekit.io>>> <>> http://www.machinekit.io < > http://www.machinekit.io>>> >>> <>> >> http://www.machinekit.io < > http://www.machinekit.io>>> <>> http://www.machinekit.io < > http://www.machinekit.io>>> >>> >> blog: > >> >> > http://blog.machinekit.io <http://blog.machinekit.io>>> <>> > http://blog.machinekit.io <http://blog.machinekit.io>>> >>> <>> >> > http://blog.machinekit.io <http://blog.machinekit.io>>> <>> > http://blog.machinekit.io <http://blog.machinekit.io>>> >>> >> github: > > >> >> https://github.com/machinekit <https://github.com/machinekit>>> > <>> https://github.com/machinekit <https://github.com/machinekit>>> >>> > <>> >> https://github.com/machinekit <https://github.com/machinekit>>> > <>> https://github.com/machinekit <https://github.com/machinekit>>> >>> > > > >>> >> > --- > >>> >> > You received this message because you are subscribed to the > Google Groups "Machinekit" group. > >>> >> > To unsubscribe from this group and stop receiving emails from > it, send an email to > >> machi...@>> >> googlegroups.com < > http://googlegroups.com>>> <>>> <mailto:>> machinekit+>> >> > unsub...@googlegroups.com <>>> <>>> >> . > >>> >> > To view this discussion on the web visit > >> >> > https://groups.google.com/d/ <https://groups.google.com/d/>>> >> > msgid/machinekit/a9420e6d->> 4f39-46e2-97c1-d4f7af69c89e%>> >> > 40googlegroups.com <http://40googlegroups.com>>> <>> > https://groups.google.com/d/>> msgid/machinekit/a9420e6d->> > 4f39-46e2-97c1-d4f7af69c89e%>> 40googlegroups.com < > https://groups.google.com/d/msgid/machinekit/a9420e6d-4f39-46e2-97c1-d4f7af69c89e%40googlegroups.com>>> > > >>> <>> >> https://groups.google.com/d/ <https://groups.google.com/d/>>> > >> msgid/machinekit/a9420e6d->> 4f39-46e2-97c1-d4f7af69c89e%>> >> > 40googlegroups.com?utm_medium= <http://40googlegroups.com?utm_medium=>>> > >> email&utm_source=footer <>> https://groups.google.com/d/>> > msgid/machinekit/a9420e6d->> 4f39-46e2-97c1-d4f7af69c89e%>> > 40googlegroups.com?utm_medium=>> email&utm_source=footer < > https://groups.google.com/d/msgid/machinekit/a9420e6d-4f39-46e2-97c1-d4f7af69c89e%40googlegroups.com?utm_medium=email&utm_source=footer>>> > > >>> >> . > >>> >> > > >>> >> > >>> >> > >>> > > >>> > > >>> > > >>> > -- > >>> > website: > >> http://www.machinekit.io <http://www.machinekit.io>>> > <>> http://www.machinekit.io <http://www.machinekit.io>>> >> blog: > >> > http://blog.machinekit.io <http://blog.machinekit.io>>> <>> > http://blog.machinekit.io <http://blog.machinekit.io>>> >> github: > >> > https://github.com/machinekit <https://github.com/machinekit>>> <>> > https://github.com/machinekit <https://github.com/machinekit>>> > > >>> > --- > >>> > You received this message because you are subscribed to the Google > Groups "Machinekit" group. > >>> > To unsubscribe from this group and stop receiving emails from it, > send an email to > >> machi...@>> googlegroups.com <>>> <mailto:>> > machinekit+>> unsub...@googlegroups.com <javascript:> <>>> >> . > >>> > To view this discussion on the web visit > >> > https://groups.google.com/d/>> msgid/machinekit/b430e32c->> > 13cc-47d2-ab88-3da6aa31a293%>> 40googlegroups.com < > https://groups.google.com/d/msgid/machinekit/b430e32c-13cc-47d2-ab88-3da6aa31a293%40googlegroups.com>>> > > <>> https://groups.google.com/d/>> msgid/machinekit/b430e32c->> > 13cc-47d2-ab88-3da6aa31a293%>> 40googlegroups.com?utm_medium=>> > email&utm_source=footer < > https://groups.google.com/d/msgid/machinekit/b430e32c-13cc-47d2-ab88-3da6aa31a293%40googlegroups.com?utm_medium=email&utm_source=footer>>> > > >> . > >>> > > >>> > >>> > >> > >> > >> > >> -- > >> website: > http://www.machinekit.io <http://www.machinekit.io>> blog: > > http://blog.machinekit.io <http://blog.machinekit.io>> github: > > https://github.com/machinekit <https://github.com/machinekit> > >> --- > >> You received this message because you are subscribed to the Google > Groups "Machinekit" group. > >> To unsubscribe from this group and stop receiving emails from it, send > an email to > machi...@googlegroups.com <javascript:> <mailto: > machinekit+unsubscr...@googlegroups.com <javascript:>>> . > >> To view this discussion on the web visit > > https://groups.google.com/d/msgid/machinekit/074a5843-6a29-4653-92a9-5fd90b428b03%40googlegroups.com > > < > https://groups.google.com/d/msgid/machinekit/074a5843-6a29-4653-92a9-5fd90b428b03%40googlegroups.com?utm_medium=email&utm_source=footer>> > > . > >> > > > > -- > > website: http://www.machinekit.io blog: http://blog.machinekit.io > github: https://github.com/machinekit > > --- > > You received this message because you are subscribed to the Google > Groups "Machinekit" group. > > To unsubscribe from this group and stop receiving emails from it, send > an email to machi...@googlegroups.com <javascript:>. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/machinekit/LpoXDXx--3-1%40tuta.io. > > > > -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to machinekit+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/machinekit/523ddc5e-5a0d-482e-8b31-f3ebe7d980b6%40googlegroups.com.
