[tester] IEEE 802.15.4 SubMAC on top of IEEE 802.15.4 Radio HAL

[jia200x]

Contribution description

This draft provides a very rough implementation of #13376. In a nutshell, this module provides a uniform layer to send and receive IEEE 802.15.4 MAC frames with retransmissions and CSMA-CA. The SubMAC emulates in software hardware features (CSMA-CA, Retransmissions, etc) missing on a given radio.

Besides that, I added a a netdev_ieee802154_submac as a transition layer. With this, default and gnrc_networking are indirectly working on top on the Radio HAL (#13943 ).

I hope this server as a proof for the Radio HAL API :)

I had to include the work by @miri64 from #11263. Since the radios are asynchronous now, there are some lost fragments when the radio returns -EBUSY during the TX process.

Testing procedure

Check tests/ieee802154_submac for the "raw SubMAC API" calls. This example supports sending and receiving data with retransmissions and CSMA-CA.
A more interesting test is running default or gnrc_networking with netdev_ieee802154_submac. With that, all radios from #14655 (CC2538, nrf802154, at86rf2xx) are working with full CSMA-CA/retransmissions support!! :)
Try adding some noise and pinging between nodes.

Issues/PRs references

#13943
#13376
#14655 (base)
#11263

[jia200x]

Here is an example of ping (300 ms interval, 1024 kb payload) between the nrf802154 and cc2538, without retransmissions:

2020-08-19 11:46:29,504 # --- fe80::2068:3123:fe42:2e25 PING statistics ---
2020-08-19 11:46:29,509 # 100 packets transmitted, 60 packets received, 40% packet loss
2020-08-19 11:46:29,514 # round-trip min/avg/max = 117.895/123.418/129.290 ms

Same example with retransmissions:

2020-08-19 11:47:12,495 # --- fe80::2068:3123:fe42:2e25 PING statistics ---
2020-08-19 11:47:12,501 # 100 packets transmitted, 100 packets received, 0% packet loss
2020-08-19 11:47:12,506 # round-trip min/avg/max = 123.342/131.136/141.767 ms

Both motes are next to me in my office. But I consistently get ~40% packet losses when I disable retransmissions (this is what we have in current master using these radios).
When I activate the SubMAC retransmissions, I consistently get ~1% packet losses.

Note the nrf52840 doesn't support Auto ACK (it's provided by the driver implementation) nor CSMA-CA/Retransmissions. The cc2538 supports Auto ACK and CSMA-CA, but no retransmissions. The SubMAC is handling the retransmission procedure for both radios and CSMA-CA for the nrf52840

[jia200x]

note: ACK request is disabled by default here. To enable it, use the ifconfig <pid> ack_req command

[jia200x]

the SubMAC got merged. We can close this PoC now!