FreeCalypso > hg > fc-magnetite
changeset 219:b05dba024f95
doc/Handset-configs and doc/Modem-configs written
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 15 Oct 2016 22:41:38 +0000 |
parents | 75ea63a3fce5 |
children | 60cc20bfe18f |
files | README doc/Handset-configs doc/Modem-configs |
diffstat | 3 files changed, 167 insertions(+), 2 deletions(-) [+] |
line wrap: on
line diff
--- a/README Sat Oct 15 19:30:58 2016 +0000 +++ b/README Sat Oct 15 22:41:38 2016 +0000 @@ -150,8 +150,8 @@ still works (doesn't break), we make this deblobbing transition permanent and move on to the next component. -See doc/Deblobbing for the current status of the deblobbing effort and for the -description of the currently available configurations. +See doc/Modem-configs for the current status of the deblobbing effort and for +the description of the currently available configurations. Further reading ===============
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/doc/Handset-configs Sat Oct 15 22:41:38 2016 +0000 @@ -0,0 +1,105 @@ +Work toward end user libre phone firmware +========================================= + +Phone handset firmware, i.e., fw that makes a phone device work as an untethered +phone and not just a serial-cable-controlled pseudo-modem, requires a few +additional layers of functionality beyond AT-command-controlled modem fw: + +* The hardware-specific LCD driver, called R2D in TI's TCS211 program; +* The actual phone UI implementation, which the cellular industry calls by the + sexist term "MMI" - TI's implementation consists of two components called BMI + and MFW; +* Battery management (monitoring and charging); +* Fairly complex on/off logic to handle all possible combinations of turn-on, + turn-off, charging while "on", charging while "off", charging completed or + failed but charging power source not unplugged yet. + +The code we got from TI with the TCS211 delivery by Sotovik includes only a +very rudimentary implementation of the above functions that basically amounts +to nothing more than a proof of concept, and is absolutely not ready for driving +a real end user phone: the UI code contains crashing and other killer bugs, the +battery management code doesn't work (fails to even monitor the battery voltage +in the discharging state, and I haven't even got to trying to charge), and the +on/off logic is broken in several ways. + +If we desire a libre phone for our pockets and purses (I do desire one for my +purse), we will have to bite the bullet and do the necessary work to transform +the UI and associated handset code from its current sorry state into something +usable, and I have started laying a little bit of the necessary foundation for +doing this work in FC Magnetite. + +There are currently two Magnetite configurations (in the ./configure.sh sense) +that include the UI layers: 2092 and 2092-pwr. 2092 is TI's bizarre "product" +number for the configuration that is just like the one we got from Sotovik +(called pdt_2091), but with BMI enabled. The difference between the plain 2092 +config and 2092-pwr is that the latter includes TI's battery management code in +the form of the old RiViera Software Entity (SWE) called PWR. (I tested the +latter on the C139 and found it to be broken.) + +If you request the 2092 configuration for a target other than c139, i.e., for +fcdev3b, gtamodem or pirelli, you will get a successful build (to be pedantic, +if you pick gtamodem, you'll get a link failure unless you tweak the linker +script, but it's a minor nit), but if you then run that fw image on the +hardware, it won't do anything good: it will try to display TI's D-Sample UI +(176x220 pixels, color) on the D-Sample LCD attached to Calypso chip select +nCS3, but of course neither Openmoko's modem nor the Pirelli has a D-Sample LCD +on that chip select, thus the LCD output would fall into the aether. (It would +be even worse in the case of the Pirelli which has the 2nd flash bank on nCS3, +thus the D-Sample LCD writes could clash with the FFS code operating on that +flash - so don't do it.) However, because BMI is enabled, the fw will still +automatically bring up the GSM radio and register to the default network +immediately upon boot like a typical UI-enabled phone does, even though the +associated LCD output will be invisible. Needless to say, this configuration +is not something I would ever advise actually running. + +However, if you build the 2092 config for the c139 target, the Magnetite build +system will enable the same hack which was originally implemented in the +tcs211-c139 side project in late 2015. Prior to the D-Sample with its fancy +176x220 pix color LCD, TI's previous development platforms (C-Sample and +earlier) had 84x48 pix black&white (1 bit per pixel) LCDs, and this old C-Sample +LCD support is still there in TCS211, albeit in a bitrotten form that wouldn't +even compile without a lot of fixing. In our late-2015 tcs211-c139 side project +we had resurrected this C-Sample UI configuration, and this work has now been +integrated into Magnetite. When you build Magnetite in the 2092 configuration +for the c139, you will get our C139 LCD driver that pretends to be C-Sample to +the upper layers, and you will get TI's old 84x48 pix B&W UI displayed on the +phone's 96x64 pixel color LCD. IOW, only 84x48 out of the available 96x64 +pixels are used, and only 2 out of the available 65536 colors. Yes, pretty +pathetic, I know. + +My (Mychaela's) plan going forward is to build our own more proper hardware +before digging any deeper into TI's broken UI code. I am not happy at all +about having had to disable TI's D-Sample UI (the 176x220 pix color one) and +resurrect the ancient pathetic C-Sample one instead, and given the long list of +show-stopping bugs this UI code currently exhibits, I can never be sure which +of these bugs were already there in the D-Sample config this code was made for, +vs. which of these bugs could be a result of re-enabling the very bitrotten +C-Sample UI config - remember, it wouldn't even compile at first. + +As much as I would love to have a libre phone in my purse, my desire to see +TI's UI code running in its native 176x220 pix color form is even greater, hence +I have decided that I shall abstain from doing any further UI work targeting +the C139 or the Pirelli until *after* we have built my desired HSMBP: Handset +Motherboard Prototype, a Calypso board with a 176x220 pix color LCD just like +on TI's D-Sample. + +However, if anyone else in the community has a different view and sees the +making of a libre phone based on Mot C1xx or Pirelli hardware as more important +than building our own hw, please feel free to take a stab at the code yourself: +the whole point of FLOSS projects is that anyone can do what s/he wants with +the code and the project without being beholden to the leader's views. At least +some of the necessary foundation has already been laid for you. + +Deblobbing status +================= + +The current 2092 and 2092-pwr configs are based on the l1reconst modem config +(see the Modem-configs write-up), i.e., L1 is mostly rebuilt from source, but +the versions of G23M PS and ACI are the original TCS211 ones, thus the G23M PS +component is all blobs. In order to build a G23M-deblobbed UI-enabled config, +we would need to build the UI layers (MFW and BMI) on top of the new TCS3.2 +version of ACI used in the deblobbed hybrid config, and no such feat has been +attempted yet. I personally plan on tackling this direction only after we have +built my desired D-Sample-like HSMBP and brought up the original TCS211 UI in +its original form, but once again, anyone else whose priorities are different +from mine should feel free to delve into the code themselves.
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/doc/Modem-configs Sat Oct 15 22:41:38 2016 +0000 @@ -0,0 +1,60 @@ +Modem configurations +==================== + +If you would like to build our Magnetite firmware in the AT-command-controlled +modem configuration (not the C-Sample UI demo on the Mot C139), you have 3 +specific configurations to choose from, differing in the level of deblobbing: + +classic This configuration replicates classic TCS211, just like + leo2moko from 2013. Almost all of the original binary blob + libraries are used; the only components that are recompiled + from source are those which we got in source form with our copy + of TCS211 from Sotovik. This config can only be built for the + fcdev3b and gtamodem targets, not for c139 or pirelli. + +l1reconst In this configuration most of L1 (GSM Layer 1) is recompiled + from reconstructed source, although this deblobbing of L1 is + not 100% complete yet: for some pieces of L1 the original binary + object blobs are still used. Some housekeeping pieces are also + recompiled from source that had to be reconstructed. This + config can be built for all targets. + +hybrid This configuration is a TCS2/TCS3 hybrid. Instead of using the + TCS211 version of the G23M protocol stack which we got only as + binary blobs, this config uses the G23M PS version from the + TCS3.2/LoCosto source, backported to work with L1 and the fw + foundation layers from TCS211. ACI also had to be replaced with + the TCS3 version, and a special hybrid version of the cdginc + headers had to be constructed. L1 is also deblobbed to the + same extent as in l1reconst. Like l1reconst, this config can + be built for all targets, and it is currently the most deblobbed + (closest to full source) Magnetite config. + +All 3 of the above configurations have CSD, fax and GPRS enabled, i.e., include +functionality that will only become exercisable when we build our FCDEV3B and +is dead weight until then, while we limp along with the currently available +hardware. We will need to deblob more of L1 (the l1audio and l1tm modules for +which we currently still use the original object blobs) before we can try +building a functionally reduced configuration that would be more appropriate +for the feeble hardware targets. + +The deblobbing of L1 has been done in a very meticulous manner, ensuring that +each individual reconstructed C module compiles into a strict functional +equivalent of the original binary blob, sometimes even matching bit for bit - +thus no regressions are expected with the classic->l1reconst transition, and no +extensive testing is deemed necessary beyond the basic tests that have already +been done. However, the transition from l1reconst to hybrid involves wholesale +replacement of two major firmware components (G23M PS and ACI) and some +important associated support pieces with entirely different versions from a +different TI program, hence extensive testing and debugging will be needed. + +So far the most-deblobbed hybrid config looks very promising: after fixing the +hideous bug resulting from the addition of A5/3 support in TCS3.2 (hardware +feature available on LoCosto but not on Calypso), voice calls work perfectly, +both with the legacy codecs and with AMR! (The same A5/3 bugfix has also been +applied to our Citrine fw, hence the latter now has working voice calls too.) +However, it is almost certain that there are a ton of minor bugs which need to +be shaken out, hence this firmware build config should be treated as +experimental for the time being, not production. My plan is to work on shaking +out the minor bugs and bringing this hybrid fw to production quality after we +build the proper hardware platform for it, i.e., the FCDEV3B.