Re: [PATCH-2.4.20] PCI-X hotplug support for Compaq driver

[Torben Mathiasen <torben.mathiasen@hp.com>]

Sure. I started out doing the patch for 2.5, but hit some hotplug bugs so I
decided to get it working for 2.4 first and then port it to 2.5. I'll get on
that.

A few comments below.
 
> > +static char *get_speed_string (int speed)
> > +{
> > +	switch(speed) {
> > +		case(PCI_SPEED_33MHz):
> > +			return "33MHz PCI";
> > +		case(PCI_SPEED_66MHz):
> > +			return "66MHz PCI";
> > +		case(PCI_SPEED_50MHz_PCIX):
> > +			return "50MHz PCI-X";
> > +		case(PCI_SPEED_66MHz_PCIX):
> > +			return "66MHz PCI-X";
> > +		case(PCI_SPEED_100MHz_PCIX):
> > +			return "100MHz PCI-X";
> > +		case(PCI_SPEED_133MHz_PCIX):
> > +			return "133MHz PCI-X";
> > +		default:
> > +			return "UNKNOWN";
> > +	}
> > +}
> 
> Ick, why?  Just for a debugging message?  That /proc file is on the
> short list of things to delete :)
>

I wanted the user to be able to know exactly which bus speed/mode the driver
switched to in case of a freq/mode change. Besides that it also put the info in
proc as you mention.

> > --- linux-2.4.20/drivers/hotplug/pci_hotplug.h	Thu Nov 28 17:53:13 2002
> > +++ linux-2.4.20-pcix/drivers/hotplug/pci_hotplug.h	Mon Jan  6 22:54:47 2003
> > @@ -33,9 +33,10 @@
> >  enum pci_bus_speed {
> >  	PCI_SPEED_33MHz			= 0x00,
> >  	PCI_SPEED_66MHz			= 0x01,
> > -	PCI_SPEED_66MHz_PCIX		= 0x02,
> > -	PCI_SPEED_100MHz_PCIX		= 0x03,
> > -	PCI_SPEED_133MHz_PCIX		= 0x04,
> > +	PCI_SPEED_50MHz_PCIX		= 0x02,
> > +	PCI_SPEED_66MHz_PCIX		= 0x03,
> > +	PCI_SPEED_100MHz_PCIX		= 0x04,
> > +	PCI_SPEED_133MHz_PCIX		= 0x05,
> >  	PCI_SPEED_66MHz_PCIX_266	= 0x09,
> >  	PCI_SPEED_100MHz_PCIX_266	= 0x0a,
> >  	PCI_SPEED_133MHz_PCIX_266	= 0x0b,
> 
> Where are you getting the PCI_SPEED_50MHz_PCIX value from?  I took these
> values from the Hotplug PCI draft spec.  Has 02 been reserved for 50MHz
> PCIX and the other values changed?
> 
> If it's not in the spec, I'd recommend adding it to the end of the list,
> with a big comment about why it's different from the spec values.
>

Sure, we used to ship a system that only supported 50MHz PCI-X, but I'll have
to get more details on that.

Torben