Areas of Work

This page lists the various areas of the project that require some work, and who (if at all) is working on fixing it.

Infrastructure

Build System

  • we need a clean/known base as a compiler
    • At the moment, we're mostly using the 4.0.2 release from gnuarm.com, which is fairly old
  • independence of system-provided header files
    • We should be mostly there now. But testing this and verifying our independence of system headers would be great

Operating System

  • Decide which RTOS to use on the Calypso
    • we don't want to use FreeRTOS
    • OS should have clear abstraction of core (ARM7TDM), SoC and board level features
    • OS should cleanly compile to a library that we can link with all our other code
    • While we only work on the GSM stack, no OS is needed. But as soon as UI comes around, that changes.

Development Tools

  • try to make JTAG (C155) work with OpenOCD
    • steve-m made some experiments, but halting the ARM core only seems to be possible via the undocumented ICEPick unit

Host Software

  • osmocon support for the native ROM loader in the Calypso, the CalypsoRomloader, like it is found on most non-Compal phones
    • "non-secure" variant (done, steve-m)
    • "secure variant" on Calypso/Calypso? plus (basic reverse engineering done)

Target Software

Drivers

  • charger detection, battery charging (roh)
  • SIM card reader (dexter)
  • Color display driver for C155 (done, steve-m)
  • backlight driver
  • vibrator driver
  • buzzer driver for C123
  • C155 ringtone chip driver for SPMA100 chip
  • Fix the I2C driver to use the b/w LCD without any sleep/delay loops
    • done (sigwinch)

GSM Stuff

  • TRF6151, TPU, TSP, AGC, AFC (laforge)
  • Layer1, particularly the synchronous part (laforge, spaar)
  • Layer2 (zecke, laforge)
  • Layer3 (eversberg)
  • Playing with the Voice part using the dsp misc task (spaar?)

General Infrastructure

  • Flash-based log-structured filesystem (prom)

Bootloader

  • Put together a bootloader (prom)
  • Define linkage situations (prom)

UI related

  • proportional fonts in at least two sizes, as small as possible
    • monospaced fonts waste too much scarce screen real estate
  • cache the frame buffer in RAM and sync when needed
    • once we have a scheduler and tasks, run screen refresh as low-priority task
  • hardware independent API to support C123, C155 (and later other) displays
    • software should not care if it is using color or b/w display
  • some kind of fixed screen layout masks, where
    • a data structure defines a screen mask
    • the application can easily update the content without having to deal with formatting/positioning
  • UI widgets like
    • lists that can be scrolled through
    • menus build of a tree of such lists