Hi Vinicius, On Wed, 27 May 2020 at 21:25, Vinicius Costa Gomes <vinicius.go...@intel.com> wrote: > > Hi, > > Vladimir Oltean <olte...@gmail.com> writes: > > > From: Vladimir Oltean <vladimir.olt...@nxp.com> > > > > SJA1105, being AVB/TSN switches, provide hardware assist for the > > Credit-Based Shaper as described in the IEEE 8021Q-2018 document. > > > > First generation has 10 shapers, freely assignable to any of the 4 > > external ports and 8 traffic classes, and second generation has 16 > > shapers. > > > > We also need to provide a dummy implementation of mqprio qdisc offload, > > since this seems to be necessary for shaping any traffic class other > > than zero. > > > > The Credit-Based Shaper tables are accessed through the dynamic > > reconfiguration interface, so we have to restore them manually after a > > switch reset. The tables are backed up by the static config only on > > P/Q/R/S, and we don't want to add custom code only for that family, > > since the procedure that is in place now works for both. > > > > Tested with the following commands: > > > > data_rate_kbps=34000 > > port_transmit_rate_kbps=1000000 > > idleslope=$data_rate_kbps > > sendslope=$(($idleslope - $port_transmit_rate_kbps)) > > locredit=$((-0x7fffffff)) > > hicredit=$((0x7fffffff)) > > tc qdisc add dev sw1p3 root handle 1: mqprio num_tc 8 > > This (and implementing the dummy mqprio offload callback) seem a bit > hackish: I am reading this is more a way to bypass mqprio parameter > validation (the priority to queue mapping) than anything else. > > And I don't think that accepting any parameters without doing any > validation is really what you want. > > Question: > > $ tc qdisc replace dev $IFACE parent root handle 100 mqprio \ > num_tc 3 \ > map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \ > queues 1@0 1@1 1@2 \ > hw 0 > > $ tc qdisc replace dev $IFACE handle 200 parent 100:1 cbs \ > idleslope 100000 sendslope -900000 hicredit 150 locredit -1362 \ > offload 1 > > Why doesn't something like this work for your hardware? > > > Cheers, > -- > Vinicius
No, it absolutely does, thanks. I had tried a few combinations of tc mqprio commands with hw 0, and they all returned this cryptic: tc qdisc add dev swp2 root handle 100 mqprio num_tc 8 map 0 1 2 3 4 5 6 7 hw 0 RTNETLINK answers: Invalid argument tc qdisc add dev swp2 root handle 100 mqprio num_tc 8 hw 0 RTNETLINK answers: Invalid argument which I had absolutely no desire to debug, especially since the same commands, with hw 1, were accepted. I just chose to be deliberately wrong, knowing that it's the quickest way to find out the real solution :) Cheers, -Vladimir
