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Re: Slot number in Desk-top - huh?



Henry,

the software you mentioned as far as I know
reports device numbers, not those of slots.
Enumeration of devices on PCI bus can be
done by means of PCI scanning but obtaining
information on physical device locations does
require additional knowledge such as that
provided by BIOS in ACPI tables or in IRT
returned by PCI BIOS v2.1+ call. I do not know
whether BIOSes normally follow marking scheme
used by mainboard manufacturer or simply assume
devices reported by the chipset be on-board, all
others to have slot number = device number - device
number of last on-board device.

Regards,
Alexander

> Mike,
> 
> 
> I do not quite understand this issue. If what you said is true, why so many
> software can find all PCI boards and corresponding bus number, slot number and
> function number, for instance PCIVIEW and Unix command lspci? I do not know
> how they do it. But they really can.
> However, physically, PCI slots can be numbered in either direction. The slot 1
> could be any of two side slots.
> 
> Henry Gong
> 
> 
> Mike Dini wrote:
> 
> > I'm confused as to how the original question deviated into the IRQ's,
> > unless I misunderstood the original question.  I thought Dinesh asked the
> > following question (paraphrasing):
> >
> >     I have a board plug into PCI/PCIX/ et al.
> >     How does the driver determine the physical
> >     location of that board?
> >
> > My private answer to him went as follows:
> >
> > You can't.  This is a fundamental problem with PCI and it is a problem we
> > have all the time.  On a PCI bus, you can figure what board is plugged in,
> > but it is impossible to determine which physical slot the board is plugged
> > into.  This is all PCI, not just Sun.  This can be quite troublesome if you
> > put two of the same boards into a system and, for example, they get cabled
> > differently to something external.
> >
> > The only way to solve this is to put a DIP switch on the PWB or add some
> > sort of an ID to the circuit.  Upon installation, the user (or other) must
> > tell the driver which of these ID's in connected to which function.
> >
> > Now I state again in clearer prose:  Across platforms, it is impossible in
> > PCI to correctly determine the physical location of a PCI resource without
> > some external intervention.
> >
> > Agree/Disagree?
> >
> > >|
> > >| Hi Experts,
> > >|
> > >| I have a basic qry.
> > >| In a desk-top environment, is there a mechanism to find out which
> > >| PCI card/resource is plugged in to which slot ? In other words, is
> > >| it possible in OS level  to read slot number of a particular PCI
> > >| card plugged in to a desk-top ?  Assume the machine is running in
> > >| Solaris/Linux.
> > >| Any one experienced similar problems ?
> > >|
> > >| Thanks in advance
> > >|
> > >| Dinesh
> 
----- Original Message ----- 
From: "Henry Gong" <hgong@cisco.com>
To: "Mike Dini" <mdini@dinigroup.com>
Cc: <pci-sig@znyx.com>
Sent: Thursday, January 09, 2003 12:03 AM
Subject: Re: Slot number in Desk-top - huh?


> Mike,
> 
> 
> I do not quite understand this issue. If what you said is true, why so many
> software can find all PCI boards and corresponding bus number, slot number and
> function number, for instance PCIVIEW and Unix command lspci? I do not know
> how they do it. But they really can.
> However, physically, PCI slots can be numbered in either direction. The slot 1
> could be any of two side slots.
> 
> Henry Gong
> 
> 
> Mike Dini wrote:
> 
> > I'm confused as to how the original question deviated into the IRQ's,
> > unless I misunderstood the original question.  I thought Dinesh asked the
> > following question (paraphrasing):
> >
> >     I have a board plug into PCI/PCIX/ et al.
> >     How does the driver determine the physical
> >     location of that board?
> >
> > My private answer to him went as follows:
> >
> > You can't.  This is a fundamental problem with PCI and it is a problem we
> > have all the time.  On a PCI bus, you can figure what board is plugged in,
> > but it is impossible to determine which physical slot the board is plugged
> > into.  This is all PCI, not just Sun.  This can be quite troublesome if you
> > put two of the same boards into a system and, for example, they get cabled
> > differently to something external.
> >
> > The only way to solve this is to put a DIP switch on the PWB or add some
> > sort of an ID to the circuit.  Upon installation, the user (or other) must
> > tell the driver which of these ID's in connected to which function.
> >
> > Now I state again in clearer prose:  Across platforms, it is impossible in
> > PCI to correctly determine the physical location of a PCI resource without
> > some external intervention.
> >
> > Agree/Disagree?
> >
> > >|
> > >| Hi Experts,
> > >|
> > >| I have a basic qry.
> > >| In a desk-top environment, is there a mechanism to find out which
> > >| PCI card/resource is plugged in to which slot ? In other words, is
> > >| it possible in OS level  to read slot number of a particular PCI
> > >| card plugged in to a desk-top ?  Assume the machine is running in
> > >| Solaris/Linux.
> > >| Any one experienced similar problems ?
> > >|
> > >| Thanks in advance
> > >|
> > >| Dinesh
>