5G Bands Configuration for Sierra EM919x modem

[Aleksander Morgado]

Hey!

>
> I recall there was some discussion about this here sometime back. Is there a way to see & configure NR5G bands in Sierra EM919x modems? We do not see these bands in below output. (I'm using MM 1.18.8)
>
> Thanks
>
> # mmcli -m 0
>   ----------------------------------
>   General  |                   path: /org/freedesktop/ModemManager1/Modem/0
>            |              device id: 6784036630561855589b4930599ad9d0c56444b5
>   ----------------------------------
>   Hardware |           manufacturer: Sierra Wireless, Incorporated
>            |                  model: Sierra Wireless EM9190
>            |      firmware revision: 03.09.06.00_GENERIC
>            |         carrier config: default
>            |           h/w revision: EM9190
>            |              supported: gsm-umts, lte, 5gnr
>            |                current: gsm-umts, lte, 5gnr
>            |           equipment id: 351735110127483
>   ----------------------------------
>   System   |                 device: /sys/devices/platform/soc/soc:internal-regs/f10f0000.usb3/usb3/3-1
>            |                drivers: cdc_mbim, qcserial
>            |                 plugin: sierra
>            |           primary port: cdc-wdm0
>            |                  ports: cdc-wdm0 (mbim), ttyUSB0 (at), ttyUSB1 (qcdm), wwan0 (net)
>   ----------------------------------
>   Numbers  |                    own: 9108813566
>   ----------------------------------
>   Status   |         unlock retries: sim-pin2 (1)
>            |                  state: connected
>            |            power state: on
>            |            access tech: lte
>            |         signal quality: 41% (recent)
>   ----------------------------------
>   Modes    |              supported: allowed: 3g; preferred: none
>            |                         allowed: 4g; preferred: none
>            |                         allowed: 3g, 4g; preferred: 4g
>            |                         allowed: 3g, 4g; preferred: 3g
>            |                         allowed: 5g; preferred: none
>            |                         allowed: 4g, 5g; preferred: 5g
>            |                         allowed: 4g, 5g; preferred: 4g
>            |                         allowed: 3g, 5g; preferred: 5g
>            |                         allowed: 3g, 5g; preferred: 3g
>            |                         allowed: 3g, 4g, 5g; preferred: 5g
>            |                         allowed: 3g, 4g, 5g; preferred: 4g
>            |                         allowed: 3g, 4g, 5g; preferred: 3g
>            |                current: allowed: 4g, 5g; preferred: 5g
>   ----------------------------------
>   Bands    |              supported: utran-1, utran-3, utran-4, utran-6, utran-5, utran-8,
>            |                         utran-9, utran-2, eutran-1, eutran-2, eutran-3, eutran-4, eutran-5,
>            |                         eutran-7, eutran-8, eutran-12, eutran-13, eutran-14, eutran-17,
>            |                         eutran-18, eutran-19, eutran-20, eutran-25, eutran-26, eutran-28,
>            |                         eutran-29, eutran-30, eutran-32, eutran-34, eutran-38, eutran-39,
>            |                         eutran-40, eutran-41, eutran-42, eutran-46, eutran-48, eutran-66,
>            |                         eutran-71, utran-19
>            |                current: eutran-1, eutran-2, eutran-3, eutran-4, eutran-5, eutran-7,
>            |                         eutran-8, eutran-12, eutran-13, eutran-14, eutran-17, eutran-18,
>            |                         eutran-19, eutran-20, eutran-25, eutran-26, eutran-28, eutran-29,
>            |                         eutran-30, eutran-32, eutran-34, eutran-38, eutran-39, eutran-40,
>            |                         eutran-41, eutran-42, eutran-46, eutran-48, eutran-66, eutran-71
>   ----------------------------------
>   IP       |              supported: ipv4, ipv6, ipv4v6
>   ----------------------------------
>   3GPP     |                   imei: 351735110127483
>            |          enabled locks: fixed-dialing
>            |            operator id: 40445
>            |          operator name: airtel
>            |           registration: home
>   ----------------------------------
>   3GPP EPS |   ue mode of operation: csps-2
>            |    initial bearer path: /org/freedesktop/ModemManager1/Bearer/0
>            |     initial bearer apn: internet
>            | initial bearer ip type: ipv4v6
>   ----------------------------------
>   SIM      |       primary sim path: /org/freedesktop/ModemManager1/SIM/0
>   ----------------------------------
>   Bearer   |                  paths: /org/freedesktop/ModemManager1/Bearer/1
>
>
> # mmcli -m 0 --command=AT!BAND?
>
> 0 - GW:    0000000000000000
> 1 - LTE:   0000A3E2BB0F38DF 0000000000000042
> 3 - NRNSA: 0000010008000017 0000000000007042
> 4 - NRSA:  0000010008000017 0000000000007042'
>

I think git main already has support for that, taking the NR SA mask
as the list of 5GNR bands reported by MM. MM currently ignores the
bands configured for NSA specifically, which is not ideal.

I'm really not sure what to do with "bands for NSA" and "bands for
SA". Giving one single set of bands for both in MM would mean these
settings will always be the same when managed by MM. And giving
separate sets for SA and NSA would mean trying find a more complex
solution by extending our API with new 5G specific operations and
properties for that logic. Something has to be done, though, right now
it's not perfect.

-- 
Aleksander
https://aleksander.es