This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-ia64-devel][PATCH]Change to new interrupt deliver mechanism

To: "Xu, Anthony" <anthony.xu@xxxxxxxxx>
Subject: Re: [Xen-ia64-devel][PATCH]Change to new interrupt deliver mechanism
From: Doi.Tsunehisa@xxxxxxxxxxxxxx
Date: Tue, 05 Dec 2006 13:04:47 +0900
Cc: xen-ia64-devel <xen-ia64-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Mon, 04 Dec 2006 20:05:01 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: Your message of Fri, 01 Dec 2006 19:49:03 +0900. <200612011049.kB1An3X17764@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-ia64-devel-request@lists.xensource.com?subject=help>
List-id: Discussion of the ia64 port of Xen <xen-ia64-devel.lists.xensource.com>
List-post: <mailto:xen-ia64-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=unsubscribe>
References: <51CFAB8CB6883745AE7B93B3E084EBE207DD85@xxxxxxxxxxxxxxxxxxxxxxxxxxxx><200612011049.kB1An3X17764@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-ia64-devel-bounces@xxxxxxxxxxxxxxxxxxx

I (Doi.Tsunehisa) said:
>   Hmm.. Current implement needs the GSI for platform-pci to follow
> status of virtual IOSAPIC in hypervisor side. But, it's not certain
> value from virtual IOSAPIC at calling set_callback_irq hypercall.
>   I'll be thinking more...

  I've investigated it, but I couldn't find the method to get GSI of
platform-pci for PV-on-HVM driver. There is convert functions like
isa_irq_to_vector() in linux kernel source.

    int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)

    inline int gsi_to_vector (unsigned int gsi)

  But, these functions are not EXPORT_SYMBOLE, thus we can't use them for
kernel module.

  So, I think that..

  * Hypervisor becomes to be able to use both GSI and Vector for callback
    - For example, if it is normal value, HV accepts it as GSI.
      If it is value which is set MSB, HV accepts it as Vector.
  * If hypervisor gets Vector as callback irq, hypervisor finds the GSI
    for the pseudo device from virtual interrupt controller setting.

  What do you think about this method ?

- Tsunehisa Doi

Xen-ia64-devel mailing list