Hi Maciej, I have read all the books you suggested and I work having all of them on my desk. I come back to them frequently to check diverse stuff. My problems are: - Why Malta implementation doesn't activate cpu_has_veic although they have 8259 external interrupt controller? Malta implementation doesn't activate cpu_has_vint too although Vectored interrupt mode should be the minimum recommended mode if external controller is not present. - Looking at Malta_xxxx specific files, it seems to me that they do not follow Linux Porting Guide document I have read on MIPS Linux. In addition, my company pays Timesys for support and regarding cpu-feature.h define switches, they said that they know nothing. What I was hoping was to find a MIPS Linux implementation which uses Vectored Interrupt Mode (VI) with few h/w interrupts including the timer routed to the MIPS processor or at least some document with some details of implementation. That will shorten significantly my porting. Sure, if I find nothing, I'll write from scratch as I understand, but it takes for sure much longer and is worth to try first finding a close example. Thanks, Andrei -----Original Message----- From: Maciej W. Rozycki [mailto:macro@xxxxxxxxxxxxxx] Sent: Wednesday, September 29, 2010 10:32 PM To: Ardelean, Andrei Cc: David Daney; linux-mips@xxxxxxxxxxxxxx Subject: RE: How to setup interrupts for a new board? Hi Andrei, > I checked in the MIPS documentation and I couldn't find relevant > information about this particular way of implementation. Unfortunately > in the MIPS kernel source there are no enough comments. With reasonable understanding what the MIPS architecture features covered by these macros, functions, etc. are you should be able to infer from Linux code what it actually does. May I suggest some reading on the architecture first then? I realise MIPS Technologies' architecture specifications may not be the best way to learn how the architecture works, so why not try a MIPS textbook instead, such as Dominic Sweetman's excellent "See MIPS Run Linux" (ISBN 978-0-12-088421-6)? While not covering such details of Linux as you are looking for, it includes related introductory subjects to get you started. And of course it covers the MIPS architecture itself. You may be able to find the book at your nearby (or less near) library. I think it's about as much as we can help -- you need to get down to understanding the details yourself or you'll be bound to asking around helplessly all the time. Maciej