Re: [Xenomai-help] IRQs and PCIs

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Leopold Palomo Avellaneda wrote:
> A Dimarts 01 Juliol 2008, Gilles Chanteperdrix va escriure:
>> Leopold Palomo Avellaneda wrote:
>>> A Dimarts 01 Juliol 2008, Gilles Chanteperdrix va escriure:
>>>> Leopold Palomo Avellaneda wrote:
>>>>> Hi,
>>>>>
>>>>> maybe is an off toppic, but probably some like me has this issue. I
>>>>> have a mainboard with several PCI and two PCIe. I can configure the
>>>>> PCIe to use with rtnet and xenomai without any important problem.
>>>>>
>>>>> The mobo has an eth and firewire and vga incorporated, so the pci are
>>>>> free. But now, I would like to add a pci network card. I have three:
>>>>> - on for our environtment
>>>>> - two for the rtnet (two robot controlers)
>>>>>
>>>>> and then I would like to have 4
>>>>> - one for another network
>>>>>
>>>>> The problem that I have and I don't know how to solve is that the new
>>>>> pci network card share an irq with another device. So, in my case, I
>>>>> have problems with this. With rtnet, I solve this using pcie devices,
>>>>> but now I cannot.
>>>>>
>>>>> I have configure the xenomai kernel following the FAQ, and I have
>>>>> tested to assign an IRQ in the BIOS. But I have not be able to make the
>>>>> interface works. I have delays in the interface, and google says ;-)
>>>>> that is a problems of sharing IRQs with the eth. And I believe in that
>>>>> ...
>>>>>
>>>>> So, thinking that I would like to use this eth in a normal environment
>>>>> (not rtnet,) but in a box using xenomai, some of you have some
>>>>> "magical" idea, kernel parameter, etc to solve this issue?
>>>>>
>>>>> Thanks in advance,
>>>> Well, maybe you can configure the cards controlled by rtnet to actually
>>>> share their irq ? Maybe this would free irqs for other cards ?
>>> it's no problem the rtnet card. I bought two pci-e and they have the MSI
>>> and irq 1275. It's the normal pci.
>>>
>>> Today I have done it work with the irqpoll option. But I don't know if
>>> this could make problems to the realtime.
>> If you are not talking about a card use by rtnet, then there is no irq
>> sharing problem.
> 
> 
> nops, because the card that use rtnet has its own module, not a "normal" 
> kernel module a rtnet. But, what happens if I have a card, that uses comedi 
> and rtdm and I need the irqpoll parameter?

What I meant is that you can share IRQs between real-time drivers, you
can share IRQs between non real-time drivers, but you can not share IRQs
between real-time and non real-time drivers.

-- 


					    Gilles.