Commit 25a712a4 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

Merge branch 'pci/scan-bridge' into next 

* pci/scan-bridge:
  PCI: Don't scan random busses in pci_scan_bridge()
  PCI: Check for child busses which use more bus numbers than allocated
  PCI: Remove pci_fixup_parent_subordinate_busnr()
  PCI: Make sure bus number resources stay within their parents bounds
  PCI: Use request_resource_conflict() instead of insert_ for bus numbers
  PCI: Assign CardBus bus number only during the second pass
  PCI: Clarify the "scan anyway" comment in pci_scan_bridge()
  PCI: Increment max correctly in pci_scan_bridge()
parents 17f2d86f fc1b2531

drivers/pci/probe.c

+29 −47
Original line number Diff line number Diff line
@@ -731,22 +731,6 @@ struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *de 
	return child;

}



static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)

{

	struct pci_bus *parent = child->parent;



	/* Attempts to fix that up are really dangerous unless

	   we're going to re-assign all bus numbers. */

	if (!pcibios_assign_all_busses())

		return;



	while (parent->parent && parent->busn_res.end < max) {

		parent->busn_res.end = max;

		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);

		parent = parent->parent;

	}

}



/*

 * If it's a bridge, configure it and scan the bus behind it.

 * For CardBus bridges, we don't scan behind as the devices will
@@ -782,7 +766,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 
	/* Check if setup is sensible at all */

	if (!pass &&

	    (primary != bus->number || secondary <= bus->number ||

	     secondary > subordinate)) {

	     secondary > subordinate || subordinate > bus->busn_res.end)) {

		dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",

			 secondary, subordinate);

		broken = 1;
@@ -805,11 +789,10 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 
			goto out;



		/*

		 * If we already got to this bus through a different bridge,

		 * don't re-add it. This can happen with the i450NX chipset.

		 *

		 * However, we continue to descend down the hierarchy and

		 * scan remaining child buses.

		 * The bus might already exist for two reasons: Either we are

		 * rescanning the bus or the bus is reachable through more than

		 * one bridge. The second case can happen with the i450NX

		 * chipset.

		 */

		child = pci_find_bus(pci_domain_nr(bus), secondary);

		if (!child) {
@@ -822,17 +805,19 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 
		}



		cmax = pci_scan_child_bus(child);

		if (cmax > max)

			max = cmax;

		if (child->busn_res.end > max)

			max = child->busn_res.end;

		if (cmax > subordinate)

			dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",

				 subordinate, cmax);

		/* subordinate should equal child->busn_res.end */

		if (subordinate > max)

			max = subordinate;

	} else {

		/*

		 * We need to assign a number to this bus which we always

		 * do in the second pass.

		 */

		if (!pass) {

			if (pcibios_assign_all_busses() || broken)

			if (pcibios_assign_all_busses() || broken || is_cardbus)

				/* Temporarily disable forwarding of the

				   configuration cycles on all bridges in

				   this bus segment to avoid possible
@@ -844,19 +829,25 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 
			goto out;

		}



		if (max >= bus->busn_res.end) {

			dev_warn(&dev->dev, "can't allocate child bus %02x from %pR\n",

				 max, &bus->busn_res);

			goto out;

		}



		/* Clear errors */

		pci_write_config_word(dev, PCI_STATUS, 0xffff);



		/* Prevent assigning a bus number that already exists.

		 * This can happen when a bridge is hot-plugged, so in

		 * this case we only re-scan this bus. */

		/* The bus will already exist if we are rescanning */

		child = pci_find_bus(pci_domain_nr(bus), max+1);

		if (!child) {

			child = pci_add_new_bus(bus, dev, ++max);

			child = pci_add_new_bus(bus, dev, max+1);

			if (!child)

				goto out;

			pci_bus_insert_busn_res(child, max, 0xff);

			pci_bus_insert_busn_res(child, max+1,

						bus->busn_res.end);

		}

		max++;

		buses = (buses & 0xff000000)

		      | ((unsigned int)(child->primary)     <<  0)

		      | ((unsigned int)(child->busn_res.start)   <<  8)
@@ -878,20 +869,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 


		if (!is_cardbus) {

			child->bridge_ctl = bctl;

			/*

			 * Adjust subordinate busnr in parent buses.

			 * We do this before scanning for children because

			 * some devices may not be detected if the bios

			 * was lazy.

			 */

			pci_fixup_parent_subordinate_busnr(child, max);

			/* Now we can scan all subordinate buses... */

			max = pci_scan_child_bus(child);

			/*

			 * now fix it up again since we have found

			 * the real value of max.

			 */

			pci_fixup_parent_subordinate_busnr(child, max);

		} else {

			/*

			 * For CardBus bridges, we leave 4 bus numbers
@@ -922,11 +900,15 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) 
				}

			}

			max += i;

			pci_fixup_parent_subordinate_busnr(child, max);

		}

		/*

		 * Set the subordinate bus number to its real value.

		 */

		if (max > bus->busn_res.end) {

			dev_warn(&dev->dev, "max busn %02x is outside %pR\n",

				 max, &bus->busn_res);

			max = bus->busn_res.end;

		}

		pci_bus_update_busn_res_end(child, max);

		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);

	}
@@ -1835,7 +1817,7 @@ int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max) 
		res->flags |= IORESOURCE_PCI_FIXED;

	}



	conflict = insert_resource_conflict(parent_res, res);

	conflict = request_resource_conflict(parent_res, res);



	if (conflict)

		dev_printk(KERN_DEBUG, &b->dev,

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