wi-fi HW and SW info for 770 and N8[01]0

[Frantisek Dufka]

Ok, so let me provide a summary of what I currently know about hardware 
and software used for wi-fi in our internet tablets. I would appreciate 
if Kalle or others could comment, fix errors, add more info or answer 
questions if possible.

Hardware:

Both 770 and 800/810 uses chips made by STMicroelectronics. 770 uses 
older STLC4370 and N8x0 uses STLC4550. Some product briefs can be found 
via google, one example is here

http://www.alldatasheet.com/datasheet-pdf/pdf/132803/STMICROELECTRONICS/STLC4370.html
http://www.alldatasheet.com/datasheet-pdf/pdf/138117/STMICROELECTRONICS/STLC4550.html

STLC4370 uses firmware called 3825.arm, 4550 uses 3836.arm
Both chips has ARM CPU and communicate with tablet over SPI bus.
Both chips seem to offer same features (except unused SDIO interface on 
4550).

Question 1 - is there some difference relevant to our tablets except 
chip size? Like internal RAM size, CPU clock and ARM architecture, 
supported encryption methods etc?

Question 2, why the driver is called cx3110x and how Conexant is related?

Software:

Wi-fi stack in implemented by:
- firmware loaded to the chip at runtime (when interface is brought up)
- closed source wi-fi stack in module umac.ko licenced from Prism (?)
- open source glue layer cx3110x which forwards packets between 
firmware and umac.ko over SPI and implements support for linux wireless 
extensions API

Questions: What parts/layers are in firmware and what in umac.ko? How 
tightly they are coupled? Is it possible to replace umac with some open 
source linux wlan stack? Where are various encryption algorithms 
implemented (WEP,TKIP,AES) i.e. does it make sense to disable some 
encryption modes for speed reasons?

Next topic is cx3110x driver itself. I'll write another mail for that.

Frantisek