+
−What this project is about
+
−==========================
+
−
+
−Welcome to FreeCalypso.  The goal is this project is to produce a Free Dumb
+
−Phone - not yet another smartphone (free or otherwise), but a "dumbphone",
+
−i.e., a traditional cellular telephone handset just like we all had and enjoyed
+
−back in the 1990s - a device with just enough hardware resources to make and
+
−receive traditional phone calls on a standard GSM network, and not one iota
+
−more.  No power-hungry application processors, just have one baseband processor
+
−that does everything from running the GSM protocol stack to responding to the
+
−user pressing buttons on the traditional numeric dialpad.  No big screens with
+
−power-hungry backlights, just a little LCD to display who is calling and the
+
−current date and time - I use my cellphone as a pocketwatch too, so my wrists
+
−stay free.
+
−
+
−But we seek to build a "dumbphone" with one VERY SPECIAL twist: namely,
+
−operational firmware for the phone (which includes everything from the UI down
+
−to GSM Layer 1, as there is no separate baseband processor) available to every
+
−end user in the form of full source code.  Hence it will be a Free Dumb Phone.
+
−We seek to achieve this "special twist" by doing the following:
+
−
+
−* We'll use the ancient TI Calypso chipset for our Free Dumb Phone instead of
+
−  whatever is the current offering from MTK or other cellular chipset company
+
−  du jour.  TI stopped making these chips ages ago, and got out of the cellular
+
−  baseband chipset business altogether, but we can still source these chips in
+
−  5-digit quantities on the Chinese surplus market.
+
−
+
−* Because we'll be using a baseband chipset from the surplus market made by a
+
−  company that long bit the dust, we will not be getting any official firmware
+
−  releases from any vendor.  Therefore, there is no one to sign any NDAs with,
+
−  and there is no one to tell us what we can or cannot do with the firmware as
+
−  we won't be getting any official firmware in the first place.
+
−
+
−* Our Free Dumb Phone will run free firmware which we put together ourselves.
+
−  When TI completely exited the cellular baseband chipset business, closed all
+
−  their offices involved with that work and laid off all of the responsible
+
−  employees, they broke their firmware into pieces and threw the pieces in the
+
−  trash.  We have picked these shattered pieces out of the trash dumpster, and
+
−  like anything else found in a dumpster, these abandonware pieces are
+
−  effectively in the public domain, and any person in the world is free to do
+
−  with them as she pleases.
+
−
+
−The "shattered pieces" aspect of the firmware needs to be re-emphasized.  TI's
+
−complete firmware suite for their Calypso chipset, also known as TCS2.1.1 or
+
−TCS211, has *not* survived the disbanding of its maker company in an intact
+
−form.  Shattered bits and pieces are all we've been able to gather through our
+
−dumpster diving efforts.
+
−
+
−Reconstructing fully-functional firmware for the Calypso from the available
+
−broken pieces is where the bulk of the hard work in our project is.  There is
+
−another project (bb.osmocom.org) seeking to produce similarly-functional fw by
+
−rewriting it completely from scratch with a totally different architecture, but
+
−the lead developer of the present FreeCalypso project has chosen the
+
−reconstruction approach as more reliable and more likely to produce the desired
+
−result.
+
−
+
−Hardware vs. software
+
−=====================
+
−
+
−Our goal is to produce a complete and usable cellphone product.  Such a product
+
−requires both hardware and software (firmware).  We need to produce both.  We
+
−could do the hw and fw subprojects in either order, but we have chosen to work
+
−on the firmware first.  By doing the fw first, we will get to exercise it on
+
−some existing phones that use the same Calypso chipset; doing the hw ahead of
+
−the fw would give us a fancy paperweight.
+
−
+
−Current status
+
−==============
+
−
+
−We are currently using the Calypso GSM modem in the Openmoko GTA02 smartphone
+
−as our bring-up vehicle.  We have our own firmware suite, compiled 100% from
+
−source with gcc (no blobs or proprietary compiler toolchains!), but we have not
+
−yet reintegrated the full GSM protocol stack in this project.  (The leo2moko
+
−side project doesn't count.)  But we are getting close: we've got the
+
−FreeNucleus RTOS by XVilka as a working replacement for the binary-only version
+
−of Nucleus used by TI, and we've got the following parts of TI's original
+
−firmware suite integrated and working:
+
−
+
−* RiViera framework and everything that runs under it, including TI's original
+
−  FFS (flash file system), RVTMUX serial channel and ETM (Enhanced Test Mode).
+
−  This part has been found in a TCS211 semi-src package.
+
−
+
−* GPF (Condat's protocol stack framework) - TI used it mostly as binary libs,
+
−  even internally, and we had to reconstruct it from pieces.  Some parts of GPF
+
−  had to be reconstructed from disassembly.  But it works beautifully now.
+
−
+
−* GSM Layer 1 code - we took the version from the LoCosto source (no official
+
−  Calypso L1 source could be found) and backported it from LoCosto to Calypso.
+
−
+
−We are now working on reintegrating the rest of the GSM protocol stack code,
+
−also taking it from the LoCosto source (the only available full source) and
+
−reintegrating it to build in our FreeCalypso environment, targeting Calypso
+
−instead of LoCosto.
+
−
+
−We have also produced some host tools for loading firmware into Calypso GSM
+
−devices, for communicating with running firmwares over the RVTMUX interface,
+
−and for manipulating TI's flash file system.  See README.hosttools for the
+
−details.
+
−
+
−Source tree
+
−===========
+
−
+
−The subtrees of this source tree are as follows:
+
−
+
−gsm-fw		The main FreeCalypso GSM firmware work, see above.
+
−
+
−target-utils	This tree contains code that runs on Calypso targets, but is
+
−		not regular firmware (gsm-fw) or a part thereof.  The two key
+
−		components built in this tree are loadagent (needed for all
+
−		targets) and compalstage (for Compal phones only), which need
+
−		to be installed on the user's host system in order for
+
−		loadtools (see README.hosttools) to do their job.
+
−
+
−ffstools	Tools that run on a Unix or GNU/Linux host; see README.hosttools
+
−loadtools	for the details.
+
−miscutil
+
−rvinterf
+
−
+
−toolchain	Scripts and patches for building the gcc+binutils toolchain
+
−		targeting ARM7, the CPU core of the Calypso GSM/GPRS baseband
+
−		processor.  You'll need to build and install this toolchain
+
−		first before you can build gsm-fw or target-utils.
+
−
+
−If you like this project and would like to see it continue to fruition, please
+
−consider making a Bitcoin donation to the human family behind it:
+
−
+
−https://blockchain.info/address/159Yx6JRJ4oMLPTYrh1jW7fQ5D5tPHdnoM