Many thanks for your reply and a friendly hat tip for all your efforts with Beaglebone.org - it is appreciated!
I was thinking that maybe GPREG30 := 0xd233c9c3 represents some debugging info but couldn't figure out what was setting it. for the default PRU firmware => yes it makes sense to have some basic REPL using rpmsg for hacking / validation PRU_RPMsg_Echo_Interrupt0 / PRU_RPMsg_Echo_Interrupt1 might be a candidate. ??? I'm not up to Git just yet so I'm not much help. Once again thank you kindly for your reply and work. On Sun, May 10, 2020 at 1:13 PM Jason Kridner <[email protected]> wrote: > > > On May 10, 2020, at 4:09 AM, V37E00E <[email protected]> wrote: > > > > Hello, > > > I’m a beginner learning about PRU with a couple of questions. I’ve been > using as reference: > > - PRU Cookbook (thank you Mark) > - Exploring BeagleBone by Derek Molloy > - TI Examples & Labs > https://processors.wiki.ti.com/index.php/PRU_Training:_Hands-on_Labs > > *Questions:* > > 1. 1. Default firmware for PRU0/1: > > root@beaglebone:~# cat /sys/class/remoteproc/remoteproc*/firmware > > am335x-pm-firmware.elf > > am335x-pru0-fw > > am335x-pru1-fw > > > > root@beaglebone:~# find / -name am335x-pru?-fw > > /lib/firmware/am335x-pru0-fw > > /lib/firmware/am335x-pru1-fw > > > > What do these programs do? I haven’t found any source code to explain > what is inside. I think the files come from TI (compiled form), but what > happens if I > > echo start > state for the default firmware? Seems strange to have this > as the default with no clues about what is inside. > > > There’s no defacto pru firmware. Robert and I discussed loading a firmware > image that puts the processor in a hold loop just to have something in > there by default. I imagine that is what this is. > > > > 2. What is the source for the __R30 pin configurations (default?. > Fresh boot => > > > Check https://github.com/beagleboard/customizations. This is where Robert > and I discussed putting it. > > root@beaglebone:~# cat /sys/kernel/debug/remoteproc/remoteproc1/regs | > grep "GPREG30 " > > GPREG30 := 0xd233c9c3 CT_REG30 := 0x40000000 > > > > I’ve looked in: > > U-Boot, am335x-boneblack-uboot, cape_universal, > AM335X-PRU-RPROC-4-14-TI-00A0 and googled around but can’t find anything > that looks like it sets __R30 at boot. > > > With a LED connected to P9-27, P9-28, P9-29: > > config-pin P9-27 pruout => LED is low > > config-pin P9-28 pruout => LED is high > > config-pin P9-28 pruout => LED is high > > For me, it seems strange that some pins would be high by "default". What > is setting these values as high??? > > > > Many thanks in advance for any clues. > > > There was nothing done to my knowledge to make these known or specific. I > suggest you provide a firmware load if you want them to be specific. > > Patches welcome. > > There are some thoughts to load the PRUs with a small REPL through rpmsg > for quick hacking. > > -- > 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 [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/3f51b584-e0bc-4474-9710-5a96f53d5177%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/3f51b584-e0bc-4474-9710-5a96f53d5177%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > -- > 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 [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/150EE7B5-2D68-4623-82E2-3180F12F0201%40gmail.com > <https://groups.google.com/d/msgid/beagleboard/150EE7B5-2D68-4623-82E2-3180F12F0201%40gmail.com?utm_medium=email&utm_source=footer> > . > -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAETrxsWmy2cGUyRXr2c%3DwjCH6_EUu2-wZy58TetkWZxzyV31gA%40mail.gmail.com.
