[ELDK] where PCI IRQ and DMA setup

bwr bwr64x at calcentral.com
Wed Jul 9 03:02:40 CEST 2008

Simple newbie questions:

I have a PCI device that is mostly operating. I think it is generating 
interrupts (electrically), but I'm not catching anything in the kernel.

I can rebuilt my kernel, but how can I tell what options were set during the 
build?  That is, looking thru the source code, how do I tell which #ifdef's were 
set? Is there a summary file or way to "grep" the kernel to determine if 
something was compiled in?

Can you give me pointers into the kernel to where PCI interrupts are set up?

My follow up would be the same questions with DMA, how to tell what's compiled 
in, and where is the kernel code that initializes it.

ELDK v4.0
Linux v2.6.18
Freescale 8548 uP based PMC board
PMC board -> PCI_INTERRUPT_LINE = 0, is a "0" IRQ vector allowed?

during driver initialization
request_irq() returned -38 which I think is
#define ENOSYS          38      /* Function not implemented */

probe_irq_on(); <cause interrupt>; probe_irq_off(); also return 0 interrupts

from kernel .config file
# DMA Engine support
# CONFIG_DMA_ENGINE is not set

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