rpmsg issue on BBB running debian 9.5 IoT

[andrew-elder]

I'm following steps here https://markayoder.github.io/PRUCookbook/05blocks/blocks.html#_compiling_and_inserting_rpmsg_pru

I started with bone-debian-9.5-iot-armhf-2018-08-12-4gb.img.xz

I updated the wget operation to match my kernel version

debian@beaglebone:~/PRUCookbook/docs/05blocks/code/module$ wget https://github.com/beagleboard/linux/raw/4.14/drivers/rpmsg/rpmsg_pru.c
--2019-05-07 13:58:48--  https://github.com/beagleboard/linux/raw/4.14/drivers/rpmsg/rpmsg_pru.c
Resolving github.com (github.com)... 192.30.253.112
Connecting to github.com (github.com)|192.30.253.112|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://raw.githubusercontent.com/beagleboard/linux/4.14/drivers/rpmsg/rpmsg_pru.c [following]
--2019-05-07 13:58:48--  https://raw.githubusercontent.com/beagleboard/linux/4.14/drivers/rpmsg/rpmsg_pru.c
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 151.101.0.133, 151.101.64.133, 151.101.128.133, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|151.101.0.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 9466 (9.2K) [text/plain]
Saving to: ‘rpmsg_pru.c.1’

rpmsg_pru.c.1                            100%[=================================================================================>]   9.24K  --.-KB/s    in 0.005s

2019-05-07 13:58:49 (1.71 MB/s) - ‘rpmsg_pru.c.1’ saved [9466/9466]

I did the make operation

debian@beaglebone:~/PRUCookbook/docs/05blocks/code/module$ make
make -C /lib/modules/4.14.65-ti-r72/build M=$PWD
make[1]: Entering directory '/usr/src/linux-headers-4.14.65-ti-r72'
  AR      /home/debian/PRUCookbook/docs/05blocks/code/module/built-in.o
  CC [M]  /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_client_sample.o
  CC [M]  /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_pru.o
  Building modules, stage 2.
  MODPOST 2 modules
  CC      /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_client_sample.mod.o
  LD [M]  /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_client_sample.ko
  CC      /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_pru.mod.o
  LD [M]  /home/debian/PRUCookbook/docs/05blocks/code/module/rpmsg_pru.ko
make[1]: Leaving directory '/usr/src/linux-headers-4.14.65-ti-r72'

The insmod step failed...

debian@beaglebone:~/PRUCookbook/docs/05blocks/code/module$ sudo insmod rpmsg_pru.ko                                                                                
insmod: ERROR: could not insert module rpmsg_pru.ko: Unknown symbol in module

I looked in the logs

debian@beaglebone:~/PRUCookbook/docs/05blocks/code/module$ dmesg | tail
[   19.437958] configfs-gadget gadget: high-speed config #1: c
[   19.846949] IPv6: ADDRCONF(NETDEV_UP): usb0: link is not ready
[   20.041197] IPv6: ADDRCONF(NETDEV_UP): usb1: link is not ready
[   20.175895] IPv6: ADDRCONF(NETDEV_CHANGE): usb0: link becomes ready
[   26.422324] random: crng init done
[   26.422349] random: 7 urandom warning(s) missed due to ratelimiting
[ 1308.937572] rpmsg_pru: loading out-of-tree module taints kernel.
[ 1308.938008] rpmsg_pru: Unknown symbol __register_rpmsg_driver (err 0)
[ 1308.938062] rpmsg_pru: Unknown symbol unregister_rpmsg_driver (err 0)
[ 1308.938131] rpmsg_pru: Unknown symbol rpmsg_send (err 0)

Do I have the wrong version of rpmsg_pru.c?

[andrew-elder]

Looks like it is already loaded

debian@beaglebone:~/PRUCookbook/docs/05blocks/code$ lsmod | grep pru
rpmsg_pru              16384  0
rpmsg_core             16384  1 rpmsg_pru
pru_rproc              28672  0
pruss                  16384  1 pru_rproc
pruss_intc             16384  1 pru_rproc

[MarkAYoder]

Yes, it's already loaded in the current images.