Interrupts handling?

[Garcia Jérémie]

Hi everybody,

Although I am a newbie in linux powerPC development, I am in charge of a related project.
The project is the following: I have to move a vXWorks application to a Linux (montavista) environnment with a 405EP processor. Unfotunately, my knowledges are very limited in BSP and with all the board specific functions (device drivers too...).
In my application, we assign IRQ only at its early beginning and we never change them after. Furthermore, this application uses an OS API layer in order to make it independant of the OS used. For exemple we encapsulate all the OS calls in this layer ; as that we theoretically only have to change this file to use another OS. To finish, we use POSIX pthreads to get an equivalent of vxWorks tasks.
Giving that, here are my questions:

 - is it possible to write a driver in this "file" (OS API Layer) or wherever I want?
 - do I need to use kernel modules even if I need to register my driver only one time?
 - is it possible for my application to register itself a driver or is it only a "kernel job"?
 - I have to map other vxWorks routines as "intEnable", "intDisable" which respectively enable/disable specified interrupt bit : may I use the linux equivalent "enable_irq" and "disqble_irq" and that wherever and whenever I want? (same question for the "request_irq" routine) 

Tks a lot for your precious help cause over here I am really alone on that project and none use Linux!

Jérémie