[ECOS] Using FIQ for ARM PID7t

[ECOS] Using FIQ for ARM PID7t

[Amlan Chakraborty]

Hi


We are using ECOS for our application.
We have configured ECOS for ARM PID7t board.

We have a query :

1) How do we route some hardware interrupt (say timer) to the  FIQ
vector of ARM using ECOS

We are able to attach a harware interrupt using the kernel APIs
cyg_interrupt_create / cyg_interrupt_attach but the interrupt gets
routed to IRQ. When we try to set the same interrupt for FIQ it doesn't
work.

It gives the following

Spurious Interrupts : vector : 0 data : 0


Regards Amlan

Re: [ECOS] Using FIQ for ARM PID7t

[Andrew Lunn]

> 1) How do we route some hardware interrupt (say timer) to the  FIQ
> vector of ARM using ECOS

It can be done, but you have a write a VSR not an ISR. The VSR will be
installed directly into the interrupt vector, so you have to do all
the register saving etc plus you have to work out the source of the
interrupt to call the appriopriate device driver etc. 
 
> It gives the following
> 
> Spurious Interrupts : vector : 0 data : 0

By default the same code handles both FIQ and IRQ interrupts, but it
only knows how to find the source of IRQ interrupts. If a FIQ
interrupt happens it cannot locate the source and so returns vector
0. Unless you have installed an interrupt handler on this vector the
default handler will be called which causes this assertion.

        Andrew