Re: PCI/IRQ hardware question

Rick Miles wrote:
> Robert Moonen is a darn nice person I don't care what anybody says!
> 
>>Kernel irq sharing in no way implies hardware irq sharing capabilities.
>>
> 
> Perhaps it is a matter of my wording, say,  share as in process, or share as 
> in bed.. My initial search led me to correspondence between kernel hackers 
> but the excerpts below from an email on another list at another time seems to 
> imply the same sort of thing in a more understandable way.
> <snip>
> What happens when cards are sharing interrupts is that when the
> interrupt is received, the kernel queries each driver that is using the
> interrupt, basically asking "Was that your interrupt?". The driver in
> turn reads the appropriate register on it's PCI card to determine
> whether it was the one, and responds accordingly. When the device is
> found, the interrupt service routine for it is executed. Pretty simple,
> and when used correctly it works quite well. And the vast majority of
> cards and drivers out there do use it correctly.
> <snip>

What I am referring to when I speak of hardware interrupt sharing is
ACPI, now it is true that any machine these days will have functioning
ACPI hardware, but since you didn't mention anything about your hardware
I can't be sure.

A snippet cut from my dmesg file:
ACPI: Using PIC for interrupt routing
ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 6 7 9 10 *11 12 14 15)
ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 6 7 9 *10 11 12 14 15)
ACPI: PCI Interrupt Link [LNKC] (IRQs *3 4 5 6 7 9 10 11 12 14 15)
ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 *5 6 7 9 10 11 12 14 15)
ACPI: PCI Root Bridge [PCI0] (00:00)
PCI: Probing PCI hardware (bus 00)
ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT]
ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.PCI1._PRT]

Perhaps you could see what is happening with your IRQ's in your dmesg file.

Sorry for the confusion Rick.

-- 
regards
Robert G. Moonen
registered Linux user number 298132

On two occasions I have been asked [by members of Parliament],
'Pray, Mr. Babbage, if you put into the machine wrong figures,
will the right answers come out?'
I am not able rightly to comprehend the kind of confusion of ideas
that could provoke such a question.

Charles Babbage.