Commit b30742aa authored Jun 23, 2016 by Lorenzo Pieralisi Committed by Bjorn Helgaas Jun 23, 2016

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>

parent dcce0f15

arch/arm/kernel/bios32.c

+9 −11

Original line number	Diff line number	Diff line
		@@ -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)) {
		struct pci_bus *child;

		/*
		* Size the bridge windows.
		* We insert PCI resources into the iomem_resource and
		* ioport_resource trees in either pci_bus_claim_resources()
		* or pci_bus_assign_resources().
		*/
		pci_bus_size_bridges(bus);
		if (pci_has_flag(PCI_PROBE_ONLY)) {
		pci_bus_claim_resources(bus);
		} else {
		struct pci_bus *child;

		/*
		* Assign resources.
		*/
		pci_bus_size_bridges(bus);
		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);
		}
		}