Re: proper way to assign fixed PCI resources to a "hotplug" device

[Greg KH <greg@kroah.com>]

On Fri, Mar 03, 2006 at 11:42:03AM -0600, Kumar Gala wrote:
> I was wondering what the proper way to assign and setup a single PCI  
> device that comes into existence after the system has booted.  I have  
> an FPGA that we load from user space at which time it shows up on the  
> PCI bus.

Idealy your BIOS would set up this information :)

> It has a single BAR and I need to assign it at a fixed address in PCI  
> MMIO space.
> 
> All of the exported interfaces I see have to do with having the  
> kernel assign the BAR automatically for me.
> 
> the following looks like what I want to do:
> 
> bus = pci_find_bus(0, 3);
> dev = pci_scan_single_device(bus, devfn);
> pci_bus_alloc_resource(...);
> pci_update_resource(dev, dev->resource[0], 0);
> pci_bus_add_devices(bus);
> 
> However, pci_update_resource() is not an exported symbol, so I could  
> replace that code with the need updates to the actual BAR.
> 
> Is this the "right" way to go about this or is there a better  
> mechanism to do this.

Take a look at how the compat pci hotplug driver does this, you probably
just need to do the same as it.

thanks,

greg k-h