1 files changed, 149 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c
new file mode 100644
index 000000000..0fe251c6a
--- /dev/null
+++ b/arch/powerpc/kernel/pci-hotplug.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c"
+ *
+ * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
+ * Copyright (C) 2005 International Business Machines
+ *
+ * Updates, 2005, John Rose <johnrose@austin.ibm.com>
+ * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
+ * Updates, 2013, Gavin Shan <shangw@linux.vnet.ibm.com>
+ */
+
+#include <linux/pci.h>
+#include <linux/export.h>
+#include <linux/of.h>
+#include <asm/pci-bridge.h>
+#include <asm/ppc-pci.h>
+#include <asm/firmware.h>
+#include <asm/eeh.h>
+
+static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
+					       struct device_node *dn)
+{
+	struct pci_bus *child = NULL;
+	struct pci_bus *tmp;
+
+	if (pci_bus_to_OF_node(bus) == dn)
+		return bus;
+
+	list_for_each_entry(tmp, &bus->children, node) {
+		child = find_bus_among_children(tmp, dn);
+		if (child)
+			break;
+	}
+
+	return child;
+}
+
+struct pci_bus *pci_find_bus_by_node(struct device_node *dn)
+{
+	struct pci_dn *pdn = PCI_DN(dn);
+
+	if (!pdn  || !pdn->phb || !pdn->phb->bus)
+		return NULL;
+
+	return find_bus_among_children(pdn->phb->bus, dn);
+}
+EXPORT_SYMBOL_GPL(pci_find_bus_by_node);
+
+/**
+ * pcibios_release_device - release PCI device
+ * @dev: PCI device
+ *
+ * The function is called before releasing the indicated PCI device.
+ */
+void pcibios_release_device(struct pci_dev *dev)
+{
+	struct pci_controller *phb = pci_bus_to_host(dev->bus);
+	struct pci_dn *pdn = pci_get_pdn(dev);
+
+	if (phb->controller_ops.release_device)
+		phb->controller_ops.release_device(dev);
+
+	/* free()ing the pci_dn has been deferred to us, do it now */
+	if (pdn && (pdn->flags & PCI_DN_FLAG_DEAD)) {
+		pci_dbg(dev, "freeing dead pdn\n");
+		kfree(pdn);
+	}
+}
+
+/**
+ * pci_hp_remove_devices - remove all devices under this bus
+ * @bus: the indicated PCI bus
+ *
+ * Remove all of the PCI devices under this bus both from the
+ * linux pci device tree, and from the powerpc EEH address cache.
+ */
+void pci_hp_remove_devices(struct pci_bus *bus)
+{
+	struct pci_dev *dev, *tmp;
+	struct pci_bus *child_bus;
+
+	/* First go down child busses */
+	list_for_each_entry(child_bus, &bus->children, node)
+		pci_hp_remove_devices(child_bus);
+
+	pr_debug("PCI: Removing devices on bus %04x:%02x\n",
+		 pci_domain_nr(bus),  bus->number);
+	list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
+		pr_debug("   Removing %s...\n", pci_name(dev));
+		pci_stop_and_remove_bus_device(dev);
+	}
+}
+EXPORT_SYMBOL_GPL(pci_hp_remove_devices);
+
+/**
+ * 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 slotno, mode, max;
+	struct pci_dev *dev;
+	struct pci_controller *phb;
+	struct device_node *dn = pci_bus_to_OF_node(bus);
+
+	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.
+		 */
+		slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
+		pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
+		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);