[cgl_discussion] RE: [Fwd: hotswap and CGL (fwd)]

Rusty Lynch rusty at linux.co.intel.com
Wed Apr 30 14:36:17 PDT 2003


On Wed, 2003-04-30 at 13:15, Bloch, Jack wrote:
> Thanks for your response. Maybe I should clarify a little. We are currently
> evaluating two Linux distro's (namely SuSE's SLES8 and MontaVista). Both are
> based on 2.4 kernels but purport to support the CGL 1.1 spec including
> hotswap. I ran chckconfig and hotplug is on.
> 
> I wriote a simple driver for a cPCI board which has a hotswap PCI controller
> (in a cPCI chassis). The driver declares a MODULE_DEVICE_TABLE and has a
> simple probe and remove routine. When I load the driver via insmod, I see
> the probe routine get called for each device in the system and the remove
> routine is called on rmmod. What I do not see however, is the probe routine
> get called on insertion or on removal of device. There are a couple of
> possibilitioes here. Either their hotswap implementation is not working or
> the board is not generating the correct PCI signals/interrupts. Do you have
> any idea of how the sequence of events is supposed to be when I open the
> ejector handle?
> 
> My understanding is as follows. 
> 
> An NMI occurs on affected board.
> Board should generate the #ENUM signal
> An ISR should be linked to #ENUM and should scan the device and call the
> correct driver.

Actually the kernel signals the OS via /sbin/hotplug to indicate a
device has been installed.  A user space component is responsible for
maintaining policy on what driver to install, and then installing the
driver.

If I recall correctly, Suse added a back-port patch of the work that
Greg and Scott did for cPCI, so the user space intervention is the same
as on the 2.5 kernel.  The only difference is instead of sysfs, pcihpfs
(?? forgot the name) is used.

> 
> 
> The above is a little high level but maybe you can clarify for me.
> 
> Jack Bloch 
> Siemens ICN
> phone                (561) 923-6550
> e-mail                jack.bloch at icn.siemens.com
> 
> 
> -----Original Message-----
> From: Mika Kukkonen [mailto:mika at osdl.org]
> Sent: Wednesday, April 30, 2003 3:59 PM
> To: Bloch, Jack
> Cc: cgl_discussion at osdl.org
> Subject: [Fwd: hotswap and CGL (fwd)]
> 
> 
> Please use cgl_discussion for CGL related questions; info at osdl.org
> is something totally different ...
> 
> What comes to your question, there already is a lot of hotswap
> functionality in 2.5 kernel, here is one place to look for
> information:
> 	http://linux-hotplug.sourceforge.net/?selected=pci
> 
> Of course some of the CGL compliant distros have implemented
> additional stuff on top of that; I'll let them to comment on that.
> 
> --MiKu
> 
> -----Forwarded Message-----
> 
> > From: Bryce Harrington <bryce at osdl.org>
> > To: mika at osdl.org
> > Cc: info at osdl.org
> > Subject: hotswap and CGL (fwd)
> > Date: 30 Apr 2003 12:03:08 -0700
> > 
> > 
> > 
> > ---------- Forwarded message ----------
> > Date: Wed, 30 Apr 2003 11:58:55 -0700
> > From: "Bloch, Jack" <Jack.Bloch at icn.siemens.com>
> > To: "'info at osdl.org'" <info at osdl.org>
> > Subject: hotswap and CGL
> > 
> > I am a developer at Siemens. We are validating CGL for use in a project.
> > Hotswap is for us an extremely important feature. Is there any description
> > of how the proposal will work for a cPCI environment? I have reasd the
> OSDL
> > documents and do not find a description.
> > 
> > Jack Bloch
> > Siemens ICN
> > phone                (561) 923-6550
> > e-mail                jack.bloch at icn.siemens.com
> 
> _______________________________________________
> cgl_discussion mailing list
> cgl_discussion at lists.osdl.org
> http://lists.osdl.org/mailman/listinfo/cgl_discussion





More information about the cgl_discussion mailing list