G400E interrupts - try to unshare

Hi Joe.Yung,
I understand that there might have been an issue with not making it clear for the ++ G400P ++ in the manual. However, I am talking about a ** G400E ** - which is the PICe version of the card - and not the ++ G400P ++. For the ** G400E ** the manual under http://wiki.openvox.cn/index.php ... Installation_Manual is relevant which clearly states the following: "While G400E allows users to modify interrupt pin during firmware upgrade for avoiding conflict." So for the PCIe version I am using - the ** G400E ** - I should be able to change the interrupt pin!

Re your suggestion to use the A810 instead: Clearly that would be an option, however there are two issues: Firstly I do have the A800E which I then no longer would require and secondly as far as I understand the A810 is only available with 4 FXO plus 4 FXS slots. At the moment I do only require one port of each (probably more in the future, but I could most likely do with a total of 4). I don't know the cost of the A810 or the price difference to my current card, but I guess it boils down to a cost issue.

Clearly that is something where OpenVox could help - it it were a straight swap, I'd be more than happy to exchange my A800E against an A810 (e.g. an engineering sample?) or a smaller version with less ports if such a card exists. Could you please advise on how to possibly proceed with that? In return I would also offer to provide a write-up of a "how-to document" for using the A810 in a guest vm under linux KVM.

Thanks and regards Atom2

i] Last edited by Atom2 at 2012-5-30 17:40 [/i

Hi miaolin,
thanks for your reply. My plan is to use the G400E (and the FXS/FXO card) within a guest OS running under KVM from the host. In other words I want to pci-assign the two cards from the host (where no driver for it will be loaded and the cards will be assigned to pci-stub) to a guest vm (i.e. export the card to the guest which will then run Asterisk). The reason I want Asterisk in a guest and not running in the host is that this provides easier upgrades - one can simply swicth to another vm to test things. Also the host is better protected.

The problem currently simply is the shared interrupt which prevents a pci passthrough by pci-assign. I hope my description made my plans clearer.

A new firmware might be a way around that, but only once it is available. Do you have any idea by when that is available?

Re your statement about MSI - so in essence you are saying it is actually not really a PCIe card but rather a PCI card? As far as I understand MSI * actually is * part of the specs for PCIe.

Thanks and best regards Atom2

i] Last edited by Atom2 at 2012-5-30 17:41 [/i

Hi miaolin,
you are right, per se shared IRQs is not *always* an issue, but qemu prevents exporting / pci-assigning a device to a guest virtual machine if it uses a shared interrupt.

On the other hand you are able to avoid sharing interrupts if you use PCIe cards - and that was the whole idea of buying PCIe card as opposed to legacy PCI cards.

You are however right that sharing interrupts can not be avoided if more than 4 (legacy) PCI cards are used where each cards requiers an interrupt.

Thanks and regards Atom2

Hi Atom2,
G400E is the same, I mean, at present, G400E is also unable to modify pin during firmware upgrade for avoiding conflict.

The tool applied to G400E but that was a tentative plan(perhaps we will design it for GSM card as well) and it's was disabled in source code. In a word, it's a reservation feature for G400E.I hope my description is clear for you.

Regarding to A810, usually the module which is being attached on the board has 4 FXO/FXS channels. But we can provide 1,2,4 alternatives.(see enclosure) in terms of your requirements.Unfortunately,we dont have "how-to document" for using the A810 in a guest vm under linux KVM.