FreeCalypso > hg > fc-tourmaline
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!GPRS config: fix long-standing AT+COPS chance hanging bug
There has been a long-standing bug in FreeCalypso going back years:
sometimes in the AT command bring-up sequence of an ACI-only MS,
the AT+COPS command would produce only a power scan followed by
cessation of protocol stack activity (only L1 ADC traces), instead
of the expected network search sequence. This behaviour was seen
in different FC firmware versions going back to Citrine, and seemed
to follow some law of chance, not reliably repeatable.
This bug has been tracked down and found to be specific to !GPRS
configuration, stemming from our TCS2/TCS3 hybrid and reconstruction
of !GPRS support that was bitrotten in TCS3.2/LoCosto version.
ACI module psa_mms.c, needed only for !GPRS, was missing in the TCS3
version and had to be pulled from TCS2 - but as it turns out,
there is a new field in the MMR_REG_REQ primitive that needs to be
set correctly, and that psa_mms.c module is the place where this
initialization needed to be added.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Thu, 08 Jun 2023 08:23:37 +0000 |
| parents | a62e5bf88434 |
| children |
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FreeCalypso Tourmaline firmware project ======================================= In chronological terms, FC Tourmaline is our fourth firmware offering after Citrine, Magnetite and Selenite. FC Tourmaline supports the following two fundamental modes of operation: * AT-command-controlled modem operation (no UI) is currently unchanged from Magnetite hybrid; standard modem operation is supported on Tango/Caramel2, FCDEV3B and Openmoko hardware targets. * The new work being done in Tourmaline is phone handset functionality - the goal is to produce firmware that can operate a suitable hardware unit as an untethered end user phone. Only two hardware targets are supported in this FC Tourmaline handset UI development venture: FC Luna development platform and Motorola C139. See the following articles under doc for further details: C139-notes -- running smallbw version of the UI on Mot C139 Luna-notes -- running both UI versions on FC Luna Modem-operation -- using the modem configuration Technical details ================= Just like FC Selenite, Tourmaline is derived from the hybrid config of Magnetite. Also in common with Selenite, Tourmaline uses the new source version of Nucleus. However, unlike Selenite, Tourmaline retains sole use of the original TMS470 compiler (runs under Wine), retains the original blob versions of OSL and OSX glue components of GPF in the default config (see doc/Blob-status), and includes both modem and handset functional configs. Purpose and goal ================ As of late 2020, FreeCalypso has achieved everything that needs to be done on the modem side: our Magnetite hybrid or Tourmaline stdmodem firmware running on our Tango modem module embodies complete fulfillment of our long-standing desire for a standard GSM+GPRS modem module with fully published circuit schematics and firmware source code. No more significant work beyond maintenance is deemed to be needed on the modem side. OTOH, the other need for a FreeCalypso handset that can replace proprietary phones like Mot C1xx or Pirelli DP-L10 running their original proprietary fw still remains as unmet as it was when we started back in 2013. Thus the new FreeCalypso work direction is to finally produce this FC handset, initially in the form of FC firmware running on Mot C139 (and on FC Luna to keep up the bigcolor config) and allowing the possibility of new FreeCalypso handset hw. Seen from the perspective of handset rather than modem functionality, the direction taken in Citrine and Selenite (going for 100% blob-free compilation with gcc) is the wrong way to go. That direction would make sense if one cared only about modem functionality rather than handset, but we are currently in the opposite situation. In the case of handset functionality, going for a compiler change to gcc in our current state when so many other parts are broken and in need of fixing would be pure insanity, and we are not going there. Let us first produce a working FreeCalypso handset (with fw compiled with TMS470 under Wine, keeping the tiny remaining blobs) that can replace Mot/Pirelli's original proprietary firmwares for daily use, and *then* think about moving to 100% blob-free gcc - in this order.