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audio mode load: gracefully handle mode files of wrong AEC version Unfortunately our change of enabling L1_NEW_AEC (which is necessary in order to bring our Calypso ARM fw into match with the underlying DSP reality) brings along a change in the audio mode file binary format and file size - all those new tunable AEC parameters do need to be stored somewhere, after all. But we already have existing mode files in the old format, and setting AEC config to garbage when loading old audio modes (which is what would happen without the present change) is not an appealing proposition. The solution implemented in the present change is as follows: the audio mode loading code checks the file size, and if it differs from the active version of T_AUDIO_MODE, the T_AUDIO_AEC_CFG structure is cleared - set to the default (disabled AEC) for the compiled type of AEC. We got lucky in that this varying T_AUDIO_AEC_CFG structure sits at the end of T_AUDIO_MODE!
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 30 Jul 2021 02:55:48 +0000
parents a62e5bf88434
children
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FC Tourmaline firmware differs from Magnetite in two principal ways when it
comes to Mot C139 target support:

* C139 LCD support is implemented in a more forward-looking manner: instead of
  emulating TI's C-Sample at the lowest R2D driver level and therefore being
  forever limited to 84x48 pixel display size, Tourmaline implements a new
  96x64 pixel framebuffer, matching the native LCD size of C1xx phones.  The UI
  configuration is still black&white only though - the Mother of FreeCalypso
  has no current plans to support color UI on smaller LCD sizes than TI's
  original 176x220 pix.

* Our aftermarket FFS configuration has been changed from 64x3 at 0x3C0000 to
  64x7 at 0x300000.  Our earlier 64x3 config was chosen back in 2015, at that
  time we didn't know how much room we would end up needing for the firmware
  image vs. how much FFS content we would eventually have, and this 64x3 config
  is now deemed to be too small, allowing only one 64 KiB sector for FFS
  content.  Our new FC Tourmaline aftermarket FFS config supports up to 320 KiB
  of FFS content, matches what we use on other platforms with 4 MiB flash chips,
  leaves 3 MiB for the firmware image (our current smallbw UI fw is only 2 MiB),
  and still avoids intersection with Motorola's (or rather Compal's) original
  FFS, which is important for avoiding problems in converting C139 phones back
  and forth between Motorola and FreeCalypso firmwares.