I am trying to motivate me to do this project for months now, and I looked like nobody cared about it.
Thanks to Google webmaster tools (not Google Analytics, I care about your privacy, dear reader), I was able to see which other site linked my blog. Reddit does it! Woo-hoo!
pointfree refered to my blog in a comment. Thank you mysterious reader!
In the same comment thread is also discussed about the IceStorm project , which aimed at reverse-engineering the bitstream format of the Lattice iCE40.
I even bought a stick to give a try! 
Is it interesting for dynamique partial reconfiguration?
According to [DS1040] (v3.1, p.3-17), in slave SPI mode, the maximum input clock is 25MHz (readback is 15MHz). The FPGA can be configured using SPI interface in ~25ms (with medium frequency SPI mode, 24MHz). The bitstream is 34112KB ([TN1248], p.11). Lattice does not seem to have developped any user-friendly way to use partial reconfiguration.
According to [TN1248], p.4, the SPI configuration flow requires a CRESET_B to restart the configuration sequence.
After driving CRESET_B High or allowing it to float High, the AP must wait a minimum of 300 μs, allowing the iCE40 FPGA to clear its internal configuration memory.
Partial reconfiguration seems impossible with the iCE40 FPGA.
|||Clifford Wolf and Mathias Lasser, Project IceStorm, http://www.clifford.at/icestorm/|
|||Lattice Semi., iCEstick Evaluation Kit, http://www.latticesemi.com/icestick|
|[DS1040]||(1, 2, 3) Lattice Semi., iCE40™ LP/HX Family Data Sheet, http://www.latticesemi.com/~/media/LatticeSemi/Documents/DataSheets/iCE/iCE40LPHXFamilyDataSheet.pdf|
|||Digikey, Lattice Semiconductor Corporation ICE40HX1K-TQ144, http://www.digikey.de/product-detail/en/ICE40HX1K-TQ144/220-1565-ND/3083575|
|[TN1248]||(1, 2, 3) Lattice Semi, iCE40™ Programming and Configuration, http://www.latticesemi.com/~/media/LatticeSemi/Documents/ApplicationNotes/IK/iCE40ProgrammingandConfiguration.pdf?document_id=46502|
|[HB1011]||Lattice Semi, iCE40™ LP/HX/LM Family Handbook, http://www.mouser.com/ds/2/225/iCE40FamilyHandbook-311139.pdf|