[Linux-ia64] Re: PCI Hotplug Drivers for 2.5

Greg KH
2002-10-24T06:12:36Z

On Wed, Oct 23, 2002 at 10:59:34PM -0700, KOCHI, Takayoshi wrote:
> Hi,
>
> On Wed, 23 Oct 2002 22:10:08 -0700
> Greg KH <greg@kroah.com> wrote:
>
> > Also, why doesn't the ACPI PCI hotplug driver work for your machines?
> > I've seen it work on a very wide range of processors (i386 and ia64),
> > and manufacturers, and any specific issues with your hardware would
> > probably be better addressed with patches to the existing ACPI driver.
>
> The ACPI spec provides very limited control of actual hardware
> (With ACPI, we don't have common method for controlling such as Bus
> speed, LED etc.).
> So if a hardware comes with well-documented hotplug controller, we
> can achieve finer control over the hardware.

Ah, I didn't realize this. So for some machines (like IBM's x440), we
should stick with using the hotplug controller driver, instead of using
the ACPI driver. Sounds reasonable to me.

> The SHPC specification defines it still depends on ACPI for managing
> resources, etc. So resource management portion can be and *should be*
> shared with all PCI hotplug drivers that use ACPI for resource
> management.
>
> I think the most important thing is everyone agree on the direction
> in which we should go before we code anything, in order not to waste
> our time.

I think we now all agree that resource management should move into a
place where it can be shared by all pci hotplug drivers, right?

If so, anyone want to propose some common code? I think the stuff in
the ACPI driver that was pulled from the Compaq driver is a great start.
I can try to pull this into the core myself, but if the Intel developers
have the time, and energy, I would greatly appreciate their help (or
anyone else who wants to join in.)

thanks,

greg k-h