> Date: Thu, 17 Mar 2011 09:30:37 +0100
> From: jan.kis...@siemens.com
> To: gilles.chanteperd...@xenomai.org; krishnamurth...@hotmail.com
> CC: xenomai-core@gna.org
> Subject: Re: MSI support in Xenomai
> On 2011-03-16 14:26, Gilles Chanteperdrix wrote:
> > krishna m wrote:
> >> Hi All, I wanted to know if the latest Xenomai [Version
> >> xenomai-2.5.6] supports MSI interrupts. I am using the adeos Patch
> >> [version adeos-ipipe-2.6.37-x86-2.9-00] and corresponding Linux
> >> kernel [version: linux-2.6.37]. I have read in the Xenomai FAQ that
> >> MSI is not supported by the ipipe patch just wanted to know if the
> >> latest Xenomai and Ipipe supports MSI.
> > 
> > No.
> Strictly spoken, but it works in practice. See
> http://thread.gmane.org/gmane.linux.real-time.xenomai.users/12135
> Jan
> -- 
> Siemens AG, Corporate Technology, CT T DE IT 1
> Corporate Competence Center Embedded Linux
Hi Jan,

Thanks for the reply. I got the following info from you post and i had few 
questions related to this post:

>> - MSI[-X] usage for RTDM (ie. RT) drivers is basically fine as long as you 
>> avoid enabling/disabling from RT context (also used for quite a while here, 
>> no known issues under this restriction)
my question is are you mentioninig here that i must not be doing 
pci_enable_msi() and pci_disable_msi() inside the RTDM driver ? if not then 
where should these calls be done ? 
Right now i have ported my standerd linux driver for the PCIe card to RTDM 
drvier. This driver uses MSI. I am not enabeling or disabling MSI or IRQ any 
where in the driver while processing [i.e. in ISR or read/write]. I am 
enabeling MSI in the PCI Probe and disabeling it in the PCI remove functions. 
The problem i am facing is as soon as i get the First MSI interrupt the kernel 
oops and i get the following dump:Mar 21 21:08:34 barch kernel: BUG: unable to 
handle kernel paging request at 7f45402d
Mar 21 21:08:34 barch kernel: Oops: 0000 [#1] PREEMPT SMP 

 [note: The normal linux driver works with out any problem]. 
Please let me know your thoughts. Also is there an example PCIe RTDM driver 
using MSI that i can refer to understand more about this topic ?

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