It works for me thanks

/media/BEAGLEBONE/env.txt and /boot/uBoot/uEnv.txt has moved to /etc/default/capemgr (file which may not exist). It also has a new syntax. Add “CAPE=BB-SPI-01,BB-UART1,BB-UART2,BB-UART4” to get main ports working. Then reboot.

This did it for me. Per http://elinux.org/Beagleboard:BeagleBoneBlack_Debian and http://stackoverflow.com/questions/25977496/adding-multiple-capes-to-etc-default-capemgr-for-beaglebone-black-debian

I’m just trying to use uart1 and uart2 and test them loopback
I installed the overlays

root@beaglebone:~# echo ‘BB-UART1’ > /sys/devices/platform/bone_capemgr/slots
root@beaglebone:~# dmesg | tail
[ 29.341789] using random host ethernet address
[ 29.341881] g_ether gadget: Ethernet Gadget, version: Memorial Day 2008
[ 29.341895] g_ether gadget: g_ether ready
[ 32.470276] IPv6: ADDRCONF(NETDEV_UP): usb0: link is not ready
[ 32.716356] random: nonblocking pool is initialized
[ 51.070305] bone_capemgr bone_capemgr: part_number ‘BB-UART1’, version ‘N/A’
[ 51.070345] bone_capemgr bone_capemgr: slot #4: override
[ 51.070363] bone_capemgr bone_capemgr: Using override eeprom data at slot 4
[ 51.070381] bone_capemgr bone_capemgr: slot #4: ‘Override Board Name,00A0,Override Manuf,BB-UART1’
[ 51.073083] bone_capemgr bone_capemgr: slot #4: dtbo ‘BB-UART1-00A0.dtbo’ loaded; overlay id #0

root@beaglebone:~# cat /sys/devices/platform/bone_capemgr/slots
0: PF—- -1
1: PF—- -1
2: PF—- -1
3: PF—- -1
4: P-O-L- 0 Override Board Name,00A0,Override Manuf,BB-UART1

root@beaglebone:~# grep uart /sys/kernel/debug/pinctrl/44e10800.pinmux/pingroups
group: pinmux_uart0_pins
root@beaglebone:~# grep 980 /sys/kernel/debug/pinctrl/44e10800.pinmux/pins
pin 96 (44e10980.0) 00000037 pinctrl-single
root@beaglebone:~#

uart pins seem not muxed correctly. minicom do work, but nothing transmited through the uarts.

Please

As I tried out, I came back to statically activate the PRU’s and their pru – pins in fast mode via devicetree, so then
the uio_pruss are automatically loaded.