Robert, my hope is to learn through doing, and eventually have enough understanding of dt and enabling LKM/drivers so that I can maintain what I develop through kernel updates and the inevitable progress that will continue. So it's not just about getting things to work.
Would you kindly provide guidance, or point me to documentation I can study to understand the differences between the ti and bone kernels? Specifically, if there is information on how I can enable the uio_pruss driver that would be a good start. I'm trying to take small steps. The first was simple /dev/mem and mmap() interface to PRUSS. I realize that I won't be able to get interrupts this way, but it's a first step validating my understanding (not relying on "driver magic"). What I'm seeing is that I cannot even read/write to the PRUSS data ram or shared ram. Searching on the error log messages seems to indicate the problem is that the PRUSS clock needs to be enabled. (I think). I suspect this is part of what the uio_pruss driver does? Thanks. On Thursday, March 2, 2017 at 9:04:52 AM UTC-8, RobertCNelson wrote: > > On Wed, Mar 1, 2017 at 11:42 PM, ags <alfred.g...@gmail.com <javascript:>> > wrote: > > uname -a > > > > Linux BBBr0C0-1 4.4.30-ti-r64 #1 SMP Fri Nov 4 21:23:33 UTC 2016 armv7l > > GNU/Linux > > > > > > I am trying to use uio_pruss driver with PRUs. I have been able to make > them > > work "the old way" with 3.8 kernel, which (IIRC) used brute-force > /dev/mem > > and interrupts exposed through /dev/uio*. > > > > > > I have loaded the PRU cape to enable the PRUs. I have confirmed that I > have > > loaded the uio_pruss.ko > > > > > > I still don't see any uio* devices. > > > > > > Is there a "how-to" for the 4.4-ti kernel? I've read extensively here, > but > > not found definitive answers. It seems much of the content is in > debating > > the pros/cons of the remoteproc/uio differences. > > > > > > My application will require reading data from eMMC/SDcard (ARM > > core/userspace) and sending to PRUs for bitbanging output. I plan to > have > > the PRU use interrupts to indicate readiness for more data (in PRU > shared > > memory). Based on what I've read, this is a good application for the uio > > drivers. > > > > > > Any help/pointers to information that is current/usable for the 4.4-ti > build > > would be greatly appreciated. > > Just use the v4.4.x-bone kernel: > > cd /opt/scripts/tools/ > git pull > sudo ./update_kernel.sh --bone-kernel --lts-4_4 > > uio_pruss is enabled by default, it's up to you to load the overlay > with the pinmux'ing... > > Regards, > > -- > Robert Nelson > https://rcn-ee.com/ > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/b755c40c-2dd3-4909-8fe7-fa86b13d2e52%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
