arch/powerpc/kernel/pci-hotplug.c

Source file repositories/reference/linux-study-clean/arch/powerpc/kernel/pci-hotplug.c

File Facts

System
Linux kernel
Corpus path
arch/powerpc/kernel/pci-hotplug.c
Extension
.c
Size
4981 bytes
Lines
182
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (!((class >> 8) == PCI_CLASS_BRIDGE_PCI)) {
			slotno = PCI_SLOT(PCI_DN(start->child)->devfn);
			pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
			return;
		}
	}

	/* Iterate all siblings */
	for_each_child_of_node(start, dn) {
		class = 0;

		if (!of_property_read_u32(start->child, "class-code", &class)) {
			/* Call of pci_scan_slot on each sibling-nodes/bridge-ports */
			if ((class >> 8) == PCI_CLASS_BRIDGE_PCI) {
				slotno = PCI_SLOT(PCI_DN(dn)->devfn);
				pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
			}
		}
	}
}

/**
 * pci_hp_add_devices - adds new pci devices to bus
 * @bus: the indicated PCI bus
 *
 * This routine will find and fixup new pci devices under
 * the indicated bus. This routine presumes that there
 * might already be some devices under this bridge, so
 * it carefully tries to add only new devices.  (And that
 * is how this routine differs from other, similar pcibios
 * routines.)
 */
void pci_hp_add_devices(struct pci_bus *bus)
{
	int mode, max;
	struct pci_dev *dev;
	struct pci_controller *phb;
	struct device_node *dn = pci_bus_to_OF_node(bus);

	if (!dn)
		return;

	phb = pci_bus_to_host(bus);

	mode = PCI_PROBE_NORMAL;
	if (phb->controller_ops.probe_mode)
		mode = phb->controller_ops.probe_mode(bus);

	if (mode == PCI_PROBE_DEVTREE) {
		/* use ofdt-based probe */
		of_rescan_bus(dn, bus);
	} else if (mode == PCI_PROBE_NORMAL &&
		   dn->child && PCI_DN(dn->child)) {
		/*
		 * Use legacy probe. In the partial hotplug case, we
		 * probably have grandchildren devices unplugged. So
		 * we don't check the return value from pci_scan_slot() in
		 * order for fully rescan all the way down to pick them up.
		 * They can have been removed during partial hotplug.
		 */
		traverse_siblings_and_scan_slot(dn, bus);
		max = bus->busn_res.start;
		/*
		 * Scan bridges that are already configured. We don't touch
		 * them unless they are misconfigured (which will be done in
		 * the second scan below).
		 */
		for_each_pci_bridge(dev, bus)
			max = pci_scan_bridge(bus, dev, max, 0);

		/* Scan bridges that need to be reconfigured */
		for_each_pci_bridge(dev, bus)
			max = pci_scan_bridge(bus, dev, max, 1);
	}
	pcibios_finish_adding_to_bus(bus);
}
EXPORT_SYMBOL_GPL(pci_hp_add_devices);

Annotation

Implementation Notes