On Fri, 3 Mar 2006, Greg KH wrote:
> 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 :)
How would my BIOS know about a device that didn't exist when it booted.
Or do you mean my BIOS would load the FPGA as well so it existed.
> > 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.
I'll take a look. How about something like the following patch:
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index ea9277b..8d5caec 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -155,6 +155,42 @@ int pci_assign_resource(struct pci_dev *
return ret;
}
+int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
+{
+ struct pci_bus *bus = dev->bus;
+ struct resource *res = dev->resource + resno;
+ unsigned int type_mask;
+ int i, ret = -EBUSY;
+
+ type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
+
+ for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
+ struct resource *r = bus->resource[i];
+ if (!r)
+ continue;
+
+ /* type_mask must match */
+ if ((res->flags ^ r->flags) & type_mask)
+ continue;
+
+ ret = request_resource(r, res);
+
+ if (ret == 0)
+ break;
+ }
+
+ if (ret) {
+ printk(KERN_ERR "PCI: Failed to allocate %s resource #%d:%lx@%lx for %s\n",
+ res->flags & IORESOURCE_IO ? "I/O" : "mem",
+ resno, res->end - res->start + 1, res->start, pci_name(dev));
+ } else if (resno < PCI_BRIDGE_RESOURCES) {
+ pci_update_resource(dev, res, resno);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
+
/* Sort resources by alignment */
void __devinit
pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
