diff README @ 27:cb3f6fe694e1 default tip

README: document SE K2x0 addition
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 21 Dec 2023 21:44:43 +0000
parents d7740787396c
children
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--- a/README	Wed Dec 20 01:59:09 2023 +0700
+++ b/README	Thu Dec 21 21:44:43 2023 +0000
@@ -56,8 +56,8 @@
 brought it to with ffsagent and fc-fsio, which is the whole point of the
 exercise.
 
-Supported targets
-=================
+Supported targets (original intent)
+===================================
 
 The present FFS editor is intended to run only on those Calypso targets which
 run one of our full FreeCalypso GSM firmwares of the Magnetite/Selenite family.
@@ -86,6 +86,34 @@
 * compal and pirelli versions correspond to FreeCalypso aftermarket FFS configs
   on those targets, *NOT* Compal's or Pirelli's original FFS!
 
+Supported targets (more recent additions)
+=========================================
+
+The discovery of Sony Ericsson K200/220 phones in late 2022 has created a novel,
+not previously envisioned use case for the present FFS editor.  As of this
+writing (2023 Winter Solstice), there are no active plans to run FreeCalypso
+firmware on these SE K2x0 phones - hence by the principles of the previous
+section, this target would not qualify to be supported by the present tool.
+However, the FFS used by original/official fw on these phones is a variant of
+TIFFS, and there are some corner use cases where it may be desirable to make
+some surgical modifications to their FFS outside of the constraints imposed by
+the official fw.  This type of use case is an area where the present FFS editor
+is the best tool for the job, hence we decided to expand our scope a little
+(beyond the original intent) and support a configuration where our ffs-editor
+tool operates on an FFS instance that is not owned by FC.
+
+The SE K2x0 version of our FFS editor (ffsagent-se_k2x0.srec) operates on the
+original-manuf-defined FFS location on this SE K2x0 hardware target.  If anyone
+ever decides to port full FC firmware (beyond the present ffs-editor tool) to
+this se_k2x0 target, the Mother's recommendation would be to reuse the same FFS
+location.  Unlike the situation on Pirelli DP-L10, the flash structure on SE
+K2x0 (the layout of which flash area is used for what in the original/official
+design) does not leave an obvious unused place where an aftermarket FFS can be
+placed (not conflicting with any aspect of the official fw, FFS or otherwise),
+and the different hw design (computer connection does not apply charger-plug
+condition to Iota VRPC) eliminates the very peculiar set of issues we have to
+deal with on the Pirelli target that led to our design decisions there.
+
 compal-new vs. compal-old configs
 =================================