Just following up on this because I’m working on adding support to use this on OpenWrt. I am not sure what the issue is but perhaps it could be an issue with the MM netifd script on OpenWrt? I passed in the multiplex=$value to the connectargs then brought up the interface. Everything looks normal except it that it seems traffic is transmitted over the interface but nothing is ever received. I have tried removing the extra QMIMUX interfaces (del_mux 4,3,2) to make it close to the same configuration as when setting up with qmicli, however no joy. Is anyone able to replicate this?
Best, Nick > On 13 Aug 2022, at 17:48, Nick <mips...@icloud.com> wrote: > > I have tried using ModemManager now with `multiplex=required` in the bearer > options and it connects with 4 QMUX interfaces, netifd assigns the IP address > to the qmimux0 interface, I have a default route via that interface, > everything looks good but... I can’t ping the internet. It looks like wwan0 > is now the qmux main interface, with a large MTU (31744). Is there some > extra step required to use this? What could I be missing? > > Best, > Nick > >> On 13 Aug 2022, at 15:19, Nick <mips...@icloud.com >> <mailto:mips...@icloud.com>> wrote: >> >> I did some testing with this advice and have some results and a couple more >> questions. >> >> Bjørn, I realise now you were talking about cdc-mbim. I checked the values >> for tx_max and rx_max which are both 16384 by default on my device. I am >> able to change rx_max to 31744, which seems to improve upload slightly, but >> I cannot change tx_max (Permission denied, and after changing file >> permissions I just get an I/O error). Is that value supposed to be user >> accessible? Is this value tied to dwNtbOutMaxSize? Using cdc-mbim with these >> settings I get consistently 200Mbps, so my feeling is the bottleneck could >> be tied to these values, since I’m able to change their counterparts in the >> QMI driver. Using QMI QMAP it gets much faster than before, about 450Mbps. >> >> Another question more ModemManager related; is there a way to set up a >> connection using user-specified QMAP values like the ones Sebastian >> provided? >> >qmicli -p -d /dev/cdc-wdm0 --client-cid=1 >> >--wda-set-data-format="link-layer-protocol=raw-ip,ul-protocol=qmap,dl-protocol=qmap,dl-max-datagrams=32,dl-datagram-max-size=32768,ep-type=hsusb,ep-iface-number=4" >> > --client-no-release-cid >> >> Best, >> Nick >> >>> On 11 Aug 2022, at 17:47, Bjørn Mork <bj...@mork.no <mailto:bj...@mork.no>> >>> wrote: >>> >>> Nick <mips...@icloud.com <mailto:mips...@icloud.com>> writes: >>> >>>> Hey, >>>> >>>> I am testing a Quectel RM500Q on OpenWrt master, and have noticed to >>>> my surprise that the speed is much slower when using the qmi_wwan with >>>> MM than it is when using qmi_wwan_q and quectel-CM (Quectel’s >>>> proprietary driver and connection manager). >>> >>> This is sort of expected since the qmi_wwan driver will use one USB >>> transaction per IP packet whereas the qmi_wwan_q will buffer a number of >>> packets per transaction. >>> >>> There is some built-in support for MAP (RMNET muxing, which implies >>> buffering) in qmi_wwan. But I recommend using the more recent rmnet >>> driver for that, with qmi_wwan in pass-throuh mode. This is supported >>> by recent ModemManager/libqmi. Ref >>> https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/447 >>> >>> <https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/447> >>> >>>> Under good signal conditions the speed tops out at around 100Mbps on >>>> qmi_wwan + MM (and is a little bit faster when in MBIM mode with MM), >>>> but switching to qmi_wwan_q and quectel_CM it gets the expected >>>> 700Mbps+ where I am. Is there an easy explanation for this? Any >>>> suggestions as to what I can change to get speeds equivalent to the >>>> proprietary stack? >>> >>> I'm a little surprised that you don't get better numbers in MBIM mode. >>> It should have the same advantages as qmi_wwan_q or qmi_wwan+rmnet. I >>> must admit that I haven't done any seriuos testing of this theory myself >>> though. But "A little bit faster than 100Mbps" is unexpectedly slow. >>> I'm pretty sure we can do much better than that in MBIM mode. >>> >>> What kind of hardware is the host running? Maybe we have some alignment >>> issue punishing this hardware? Or maybe the buffers we use are >>> sub-optimal for thise host+device combo? You could try to adjust some >>> of the writable settings in /sys/class/net/wwan0/cdc_ncm/ (replace wwan0 >>> with your interface name) >>> >>> >>> >>> Bjørn >> >
