Cascoda driver stops working

[mtusnio]

In some circumstances, especially under high load, the cascoda driver stops working. Running ifconfig lowpan0 down throws:

[ 58.514110] ca8210 spi0.0: ca8210 was busy during attempted write
[ 58.540137] ca8210 spi0.0: spi write retry 1...
[ 58.545942] ca8210 spi0.0: ca8210 was busy during attempted write
[ 58.570183] ca8210 spi0.0: spi write retry 1...

Steps to reproduce:

1. leave iperf3 tests running between 2 boards using 6lowpan.

[nikhil-zinjurde-imgtec]

@mtusnio the above logs do not indicate that the ca8210 driver has stopped working, this is in fact a workaround put in by Cascoda to reload the driver when it stops. Can you please check 6lowpan ping test to confirm whether the driver has actually stopped working?

[mtusnio]

I haven't tried pinging, but in all cases running tcpdump on the interface reports no traffic at all despite clickers sending packets.

[Shpinkso]

@mtusnio is there an automated test case that is likely to be able to check this doesn't reoccur (once it's fixed)

[mtusnio]

Not at the moment, but it might be related to some of the iperf3 issues we've noticed, so it might be worth investigating that.

[mtusnio]

root@myCi40:/# ping6 -I lowpan0 fe80:0000:0000:0000:0204:a30b:0000:e4f4
PING fe80:0000:0000:0000:0204:a3[ 396.301474] ca8210 spi0.0: Link transmission unsuccessful, status = 241
0b:0000:e4f4 (fe[ 396.309368] ca8210 spi0.0: Waiting for transaction overflow to stabilise...
80::204:a30b:0:e4f4): 56 data bytes
[ 398.320172] ca8210 spi0.0: Resetting MAC...
[ 398.325240] ca8210 spi0.0: ca8210 was busy during attempted write
[ 398.350124] ca8210 spi0.0: spi write retry 1...
^C
--- fe80:0000:0000:0000:0204:a30b:0000:e4f4 ping statistics ---
15 packets transmitted, 0 packets received, 100% packet loss
root@myCi40:/# ping6 -I lowpan0 fe80:0000:0000:0000:0204:a30b:0000:e4f4
PING fe80:0000:0000:0000:0204:a30b:0000:e4f4 (fe80::204:a30b:0:e4f4): 56 data bytes
[ 423.677981] ca8210 spi0.0: Link transmission unsuccessful, status = 241
[ 423.685531] ca8210 spi0.0: Waiting for transaction overflow to stabilise...
[ 425.700212] ca8210 spi0.0: Resetting MAC...
[ 425.705190] ca8210 spi0.0: ca8210 was busy during attempted write
[ 425.730103] ca8210 spi0.0: spi write retry 1...
[ 430.671572] ca8210 spi0.0: Link transmission unsuccessful, status = 241
[ 430.679067] ca8210 spi0.0: Waiting for transaction overflow to stabilise...
[ 432.690272] ca8210 spi0.0: Resetting MAC...
[ 432.695295] ca8210 spi0.0: ca8210 was busy during attempted write
[ 432.720100] ca8210 spi0.0: spi write retry 1...

[abhijit-mahajani-imgtec]

Blocked on #295