ARM/PCI: Claim bus resources on PCI_PROBE_ONLY set-ups

We claim PCI BAR and bridge window resources in pci_bus_assign_resources(),
but when PCI_PROBE_ONLY is set, we treat those resources as immutable and
don't call pci_bus_assign_resources(), so the resources aren't put in the
resource tree.

When the resources aren't in the tree, they don't show up in /proc/iomem,
we can't detect conflicts, and we need special cases elsewhere for
PCI_PROBE_ONLY or resources without a parent pointer.

Claim all PCI BAR and window resources in the PCI_PROBE_ONLY case.

If a PCI_PROBE_ONLY platform assigns conflicting resources, Linux can't fix
the conflicts.  Previously we didn't notice the conflicts, but now we will,
which may expose new failures.

[bhelgaas: changelog, add resource comment, remove size/assign comments]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Russell King <linux@armlinux.org.uk>

diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 05e61a2..ad4710e 100644 (file)
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -515,25 +515,23 @@ void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
        list_for_each_entry(sys, &head, node) {
                struct pci_bus *bus = sys->bus;
 
-               if (!pci_has_flag(PCI_PROBE_ONLY)) {
+               /*
+                * We insert PCI resources into the iomem_resource and
+                * ioport_resource trees in either pci_bus_claim_resources()
+                * or pci_bus_assign_resources().
+                */
+               if (pci_has_flag(PCI_PROBE_ONLY)) {
+                       pci_bus_claim_resources(bus);
+               } else {
                        struct pci_bus *child;
 
-                       /*
-                        * Size the bridge windows.
-                        */
                        pci_bus_size_bridges(bus);
-
-                       /*
-                        * Assign resources.
-                        */
                        pci_bus_assign_resources(bus);
 
                        list_for_each_entry(child, &bus->children, node)
                                pcie_bus_configure_settings(child);
                }
-               /*
-                * Tell drivers about devices found.
-                */
+
                pci_bus_add_devices(bus);
        }
 }