EM7565 / carrier aggregation info

[Reinhard Speyerer]

On Wed, Nov 29, 2017 at 09:42:36AM +0100, Sebastian Sjoholm wrote:
> Hi,
> 
> Started new thread regarding this.
> 
> Regarding CA info from QMI on EM7565.
> 
> I think it can as well be firmware issue, as this seems to be very
> preliminary firmware. The modem is currently attached on an CA cell with
> B7+B7.

Hi Sebastian,

what does "very preliminary firmware" mean w.r.t. AT+GMR output?

> 
> root at SBC-121:~# ./cmd.py -c raw,'at!gstatus?'
> at!gstatus?
> !GSTATUS:
> Current Time:  115797 Temperature: 27
> Reset Counter: 1 Mode:        ONLINE
> System mode:   LTE        PS state:    Attached
> LTE band:      B7      LTE bw:      20 MHz
> LTE Rx chan:   3148 LTE Tx chan: 21148
> LTE SSC1 state:NOT ASSIGNED
> LTE SSC2 state:NOT ASSIGNED
> LTE SSC3 state:NOT ASSIGNED
> LTE SSC4 state:NOT ASSIGNED
> EMM state:     Registered      Normal Service
> RRC state:     RRC Idle
> IMS reg state: No Srv
> PCC RxM RSSI:  -51 PCC RxM RSRP:  -78
> PCC RxD RSSI:  -53 PCC RxD RSRP:  -79
> Tx Power:      -- TAC:         00c9 (201)
> RSRQ (dB):     -6.2 Cell ID:     01194703 (18433795)
> SINR (dB):     30.0
> OK
> root at SBC-121:~#  qmicli -d /dev/cdc-wdm0 --nas-get-lte-cphy-ca-info
> [/dev/cdc-wdm0] Successfully got carrier aggregation info
> DL Bandwidth: 'unknown'
> Secondary Cell Info
> Physical Cell ID: '0'
> RX Channel: '0'
> DL Bandwidth: 'unknown'
> LTE Band: 'eutran-1'
> State: 'deconfigured'
> Primary Cell Info
> Physical Cell ID: '5'
> RX Channel: '3148'
> DL Bandwidth: '20'
> LTE Band: 'eutran-8'
> Secondary Cell index: '0'

Maybe Sierra Wireless has intentionally disabled CA for early firmware
releases and the qmicli output observed is a side effect of this.
You might be able to get more information by checking AT!LTECA?
output or by looking at the ueCapabilityRAT-Container for rat-Type eutra
which the mobile sends to the network in LTE RRC traces.

It might also be helpful to crosscheck the qmicli -d /dev/cdc-wdm0
--nas-get-lte-cphy-ca-info -v output for a Telit LM940 with the EM7565
output if possible. Since the LM940 also supports 3CA according to the
data sheet the qmicli output should also contain the additional TLVs
of the EM7565 but with valid information.

Regards,
Reinhard