RFC: new RTEMS IRQ requirements (was: The eCos, QNX, ChorusOs irq handling API)

[Sergei Organov]

Here is my list of requirements. The numbers in brackets are priorities (0 is
the highest).

1.  (0)   ISR attach.
2.  (1)   Interrupt line enable/disable.
3.  (2)   Small IRQ management overhead.
4.  (2)   Short ISR latency.
5.  (3)   Specification of the state the user ISR is invoked at.
6.  (4)   IRQ ID and/or user argument being passed to user ISR.
7.  (5)   Universal IRQ ID (or call it "vector" or "symbolic name").
8.  (250) ISR detach.
9.  (251) Interrupt priorities management.
10. (252) Ability to implement drivers in a BSP-independent manner.
11. (253) Ability to implement re-usable [P]IC managers.
12. (254) IRQ ID being passed to user ISR separately from user argument.

-- 
Sergei.