The Sharp Zaurus Uses the Intel StrongArm CPU.
the SL-5500 was 266 MHZ the SL-6000 is 400 Mhz
(I sold my 5500 to buy the 6000 SWEET !!)
All the info I could find, looked to me like the imageon is a companion mulitimedia chip for embedded systems and I'm thinking theres also a CPU in there.. but I'm no embedded systems expert by any stretch of the imagination.
Nor was I able to locate anything specifically on the imageon and Linux.
so generic embedded Linux book links was the best I could suggest.
Not like you were very forthcoming in the application of the chip..
generic info breeds generic responses.. sorry but that's how things go